3% ^C^P libraries £fortlj (jlarnlma J&tate tBips book feas presented bjj Barbara Simpson NORTH CAROLINA STATE UNIVERSITY LIBRARIES S02047860 R This book is due on the date indicated below and is subject to an overdue fine as posted at the circulation desk. EXCEPTION: Date due will be earlier if this item is RECALLED. 200M/06-99-991212 - /J/ REGIONAL VETERINARY SURGERY AND OPERATIVE TECHNIQUE. BY THE SAME AUTHOR. Royal Bvo., 438 pages, 406 illustrations. A Handbook of Horse-shoeing. With Introductory Chapters on the Anatomy and Physiology of the Horse's Foot. The section on the " Practice of Shoe- ing " contains 54 full-page plates and descriptive notes supplied by Albekt Wheatley, F.R.C.V.S. 60 large pages (14£ x 10 inches), 315 illustrations An Atlas of Veterinary Surgical Operations. Demy Bvo, 42 pages, 16 full-page plates. A Surgical Operating Table for the Horse. Royal 8vo, 618 pages, 95 illustrations. Studies in Clinical Veterinary Medicine and Surgery. By P. J. Cadiot and Jno. A. W. Dollar. Royal Bvo, 785 pages, 32 ( J illustrations. Diseases of Cattle, Sheep, Goats and Swine. By G. Moussu and Jno. A. W. Dollar. REGIONAL VETERINARY SURGERY AND OPERATIVE TECHNIQUE (INCORPORATING PROF. DR. H. MOLLER'S "VETERINARY SURGERY.") JNO. A. W. DOLLAR, M.R.C.V.S., F.R.S.E., M.R I. PRESIDENT OF THE ROYAL COLLEGE OF VETERINARY SURGEONS, 1904—1905; FORMERLY VICE-PRESIDENT OF THE ROYAL INSTITUTE OF PUBLIC HEALTH ; CORRESPONDING MEMBER OF THE CENTRAL SOCIETY OF VETERINARY MEDICINE OF PARIS ; ASSOCIATE OF THE SOCIETY OF VETERINARY MEDICINE OF BRABANT (BELGIUM); LIFE MEMBER OF THE ROYAL ITALIAN SOCD3TY OF HYGIENE, ETC. 1912. TORONTO : THE J. F. HARTZ CO., LIMITED 406-408 YONGE STREET. ALL RIGHTS RESERVED. THE PRESS PRINTERS, LIMITED, TO 76, LONG ACRE, LONDON, ENGLAND BIBLIOGRAPHY. Allgemeine Chirurgie," Frohner. Handbuch der thierarztlichen Arzneimittellehre," Frohner. Journal of Comparative Pathology and Therapeutics." Lehrbuch der allgemeinen Chirurgie," H. Moller. Manual of Surgery," Rose and Carless. Operationslehre," J. Bayer. Precis de Chirurgie," Peuch and Toussaint. The Veterinarian." The Veterinary Journal." The Veterinary Record." Traite de Therapeutique chirurgicale," Cadiot and Almy. Trattato di Tecnica e Terapeutica chirurgica," Lanzillotti-Buonsanti. Veterinary Medicines," Finlay Dun. Precis de Medecine Operatoire Veterinaire," A. Degive. Medecine Canine," Cadiot and Breton. Diseases of Cattle, Sheep, Goats and Swine," Moussu and Dollar. PREFACE. Seventeen years ago I published my first serious contribution to veterinary literature, an edited translation of Professor Moller's " Veterinary Surgery." So far did the approval of the veterinary profession exceed my modest anticipations that the issue was exhausted before I could prepare a second and, for a few months, the book was out of print. Volume followed volume, but after the appearance of " Operative Technique " (1902), " Regional Surgery " (1903), and "Diseases of Cattle" (1905), it became increasingly evident that the labour of preparing fresh editions must eventually outgrow the powers of a busy veterinary practitioner, especially as each new edition calls not merely for revision but for a careful study of all the most noteworthy advances announced in veterinary literature, British, American and Continental, since the appearance of its predecessor. In producing the present volume, therefore, I have been only too glad to avail myself of the kind assistance of my friend and ever-willing helper, Professor McQueen, without whom the task could certainly not have been brought to com- pletion : to him I have the pleasure of expressing my deep obligation and my no less earnest thanks. The work now before the reader includes the main principles of a scheme originally more ambitious. For three volumes dealing respectively with Operative Technique, Regional and General Surgery, we have substituted one. In this have been retained all the chief features of the two first mentioned. By judicious editing and the use of suitable type, it has also proved possible to include within the viii PREFACE. limits of the book a great part of what had been destined for a third volume on General Surgery. Modern requirements demand not only great compression in material but moderate bulk and cost of pro- duction. In endeavouring to combine all these, no essential feature has been sacrificed, and it is earnestly hoped that this latest venture may receive at the hands of the veterinary profession no less favour- able a reception than its predecessors. JNO. A. W. DOLLAR. 56, New Bond Street, London, England, August, 1912. CONTENTS. I. General Remarks on Operations.— Their Limitations, Division, Planning the Operation, Preparation of the Animal, Place of Opera- tion, Assistance, and After-treatment . . II. Means op Control. — The Blinds, Hood, Nose and Leg Twitches, " Bull-Dogs," Loop-Twitch, Bull-Holder and Leader, Nose-Rings, and Mouth-Gags for Horses and Dogs . Restraint by Fastening a Fore to a Hind Leg, by Lifting a Fore or Hind Leg, by Securing both Hind Legs, the Hippo-Lasso . Methods of Restraining Oxen . The Side-Stick ; Cradle or Beads ; the Stocks or Trevis Operating Tables for Horses .... Casting with Ropes and Hobbles ; Cross Hobbles ; Apparatus to Prevent Spinal Fracture ..... Continental Methods of Casting ; Securing and Releasing limbs Russian Method of Single-handed Casting Securing Cattle, Sheep, Swine, Dogs and Cats for Operation . Operating Tables for Small Animals ; Complications, etc. . III. Anesthesia. — Introduction, Historical and General . General Anaesthesia ..... Anaesthesia in the Horse. — Apparatus Surgical Anaesthesia by Chloroform ; Fatal Issues, etc. Administration in the Standing Position ; Partial Anaesthesia Morphine and Chloroform, Atropine, Ether, Chloral, etc. Anaesthesia in Ruminants and Swine Anaesthesia in the Dog and Cat .... Conclusions regarding General Anaesthesia . Local Anaesthesia ...... Local Anaesthesia by Cold, Ice and Salt, Ether Spray, etc. . Local Anaesthesia by Cocaine ; by Infiltration — Schleich's method Spinal Anaesthesia in Animals . IV. Antisepsis and Asepsis. ments -Historical ; Lister's and Guerin's Experi Antiseptic and Aseptic Methods ; Wound Infection . Antiseptics— Carbolic Acid, Sublimate, Zinc Chloride, Potassium Permanganate, Hydrogen Peroxide, Mercury Biniodide, Iodine, Iodoform, Formalin, Chinosol, etc. . Disinfection of the Hands . . . . . . • Disinfection of Instruments, Suture Materials, and Dressings Disinfection of the Skin, Mouth, Nasal Cavities, Eye, Ear, Intestine, Uterus, Vagina and Foot ....•• First Dressing of Operation and of Accidental Wounds 13 16 17 19 24 28 37 38 39 41 42 44 46 50 51 55 56 59 59 Ii4 07 CONTENTS. V. Division of Tissues. — Cutting and Puncturing Instruments and Methods of using them ...... 87 Division by the Ecraseur, Elastic Ligature, Galvanic and Thermo- cauteries . . . . . . .1)0 Puncture — the Bistoury, Scalpel, Lancet, and Trocar ; Suture . Needles . . . . . . . !>."> Division of Hard Tissues — Chisels, Saws, Bone-Forceps, etc. . . 97 VI. .Methods of Uniting Wounds. — Recognised Modes of Healing Adhesives, Hooks. Bandages, Sutures, Suture-Needles, Silk. Silk worm Gut, Cat-Gut, Horsehair, Wire, and Pins . General Directions for Inserting Sutures . Skin Sutures ...... Bowel, Artery, Nerve, and Tendon Sutures 101 L02 105 107 111 VII. Methods of Preventing or Controlling Hemorrhage — H^emo- STASIS . . . . . . . .115 Haemostatic Agents — Cold, Heat, Styptics. . . . 11(5 Surgical Methods — Tourniquet, Esmarch's Bandage, Compression, Ligation, Torsion, Forci-pressure, Acupressure . . . 117 VIII. Bandaging and Dressing. — Bandage and Dressing Materials . 123 Mode of Application, Precautions, various Bandages (28 figures) 125 Bandages for Fractures ; Splints ; Poroplastic Felt . . 128 IX. Massage. — Varieties; Action and Results; Indications, and Methods of Application ..... 135 X. Phlebotomy, Scarification and Transfusion . . . 140 XL Cauterisation. — Solid and Liquid Caustics, the Actual Cautery, Thermo-Cauteries, Line and Needle Firing . . . '153 XII. Setoning. — Its value ; Positions in which Setons may be Inserted, Methods, Seton-Needles, etc. . . . . .168 XIII. Inoculation. — Its Applications, Instruments and Methods . . 172 XIV. The Injection of Medicines into the Blood Stream, Sub- cutaneous Tissue, Trachea, Larynx, or Parenchyma of Organs or Tissues. . . . . .174 XV. Castration . . . . . . .178 Castration Without Removal of the Testes— Crushing, " Bistourn- age," Subcutaneous Ligation of the Cord . . . 181 Castration by Removal of the Testes — Tearing, Scraping the Cord. Broad Crushing, Linear Crushing, Torsion, Ligation, Division by the Actual Cautery, and Castration with Clams. . . 183 Aseptic Castration . . . . . .192 (1.) Castration of Stallions. — Covered and Uncovered Methods 194 (2.) Castration of Male Ruminants. — Various Methods, Caustic Ligftture ; etc. ...... 204 (3.) Castration of Swine ..... 207* (4.) Castration of Dogs and Cats .... 207 (5.) Castration of Male Birds, Caponing, etc. . . . 208 Complications and Unfavourable Consequences . . 208 CONTENTS. (6.) Castration of Cryptorchids . . * Diagnosis of Cryptorchidism, Inguinal and Abdominal Inguinal Operation, Incision, Exploration, Perforation of the Abdominal Wall. .... Complications during and after Operation Ventral Operation, Method and Results (7.) Castration of Female Animals (Oophorectomy or Spaying) (a) Castration of the Cow— Charlier's Operation and its Modifications ..... Castration of the Cow— the Vaginal Operation, Insti ments, Methods and Results Castration of the Cow— Hoffman's Antiseptic Meth d Castration of the Cow — Operation through the Flank (b) Castration of the Sheep (c) Castration of the Mare— Indications, Operation (d) Castration of the Sow— Ventral Operation (e) Castration of the Bitch (f) Castration of Female Birds DISEASES OP THE HEAD. Diseases of the Lips and Cheeks (1.) Wounds and Bruises .... (2.) Acute Inflammation of the Lips and Cheeks (3.) Tumours of the Lips and Cheeks (4.) Paralysis of the Lips. Facial Paralysis . II. Diseases op the Mouth .... (1.) Foreign Bodies in the Mouth . (2.) Diseases of the Tongue .... Mechanical Injuries .... Acute Inflammation of the Tongue (Glossitis Acuta) Chronic Inflammation and New Growths in the (Makroglossia) .... Glossitis Chronica Insterstitialis Fibrosa Actinomycosis of the Tongue. Glossitis Actinomycot Paralysis of the Tongue (Glossoplegia) Ranula ..... Fracture of the Hyoid Bone . New Growths in the Tongue . (3.) Fracture of the Premaxillary Bone (4.) Injuries of the Interdental Space. (5.) Diseases of the Teeth .... (A) Irregularities in the Development of the Teeth Extra or Adventitious Teeth (Polyodontia, dentition) .... Irregularities in Replacement of the Teeth Displacement of the Teeth Tongue Hyper CONTENTS. (B) Irregularities of Wear in the Teeth The Angular or Sharp Mouth, the so-called Prog nathous Jaw. The Shear-like Mouth . The Wave-formed Mouth The Step-formed Mouth Premature Wear of the Teeth . The Smooth Mouth . (C) Diseases of the Tooth Proper Dental Caries (Caries Dentium) Fissures and Cavities in the Teeth Dental Tartar (Cremor Dentium) (D) Diseases of the Alveoli Alveolar Periostitis (Periostitis Alveolaris) Alveolar Periostitis in Herbivora Alveolar Periostitis in Carnivora Dental Fistula Neoplasms of the Gums and Alveoli (Epulis) Dental Tumours l J A(!E 275 276 278 280 281 282 284 284 284 286 287 289 289 289 299 301 303 305 III. Diseases of the Nose. Nostrils, and the Spaces communicating WITH THEM ...... (a) Wounds of the Ala* of the Nostrils (b) Fracture of the Nasal Bones .... (c) Foreign Bodies and Tumours in the Nostrils (d) Diseases of the Frontal and Superior Maxillary Sinuses (e) Trephining the Superior Maxillary and Frontal Sinuses (f) Necrosis of the Turbinated Bones (g) Epistaxis (Bleeding from the Nose) 305 305 306 307 311 315 321 323 IV. Diseases of the Salivary Glands .... (1.) Wounds and Injuries of the Salivary Glands . (2.) Inflammation of the Salivary Glands (Parotitis) (3.) Abscess Formation in the Sub-Parotid Lymph Glands (4.) Salivary Calculi ..... (5.) Salivary Fistula) ..... (6.) Tumours of the Salivary Glands (7.) Actinomycosis in the Parotid Region . 324 324 325 328 330 331 335 336 V. Diseases of the Face and Lower Jaw (1.) (2.) (3.) (4.) (5.) (6.) (7.) (8.) (9.) 340 Fractures of Bones of the Face .... 340 Fracture of the Lower Jaw ..... 343 Dislocation (Luxation) of the Lower Jaw . . . 340 Inflammation of the Articulation of the Jaw . . . 347 Paralysis of the Muscles of Mastication. Paralysis of the Lower Jaw (so-called) ..... 349 Periostitis and Exostosis on the Posterior Border of the Lower Jaw ...... 351 Tumours on the Lower Jaw ..... 351 Actinomycosis of the Maxilla .... 353 Inflammation and New Growths in the Submaxillary Lymph Glands ....... 355 CONTENTS. VI. Diseases of the Ear and Guttural Pouches (1.) Wounds of the External Ear . (2.) (Edema of the External Ear (Othematoma) (3.) Inflammation of the External Auditory Meatus (Otitis Externa). Otorrhcea (4.) Fistula of the Ear. Dentigerous Cysts (5.) Chronic Catarrh of the Guttural Pouches (6.) Tympanites of the Guttural Pouches . VII. Diseases of the Skull (1.) Fractures and Injuries to the Cranial Bones (2.) Concussion of the Brain (Commotio cerebri) (3.) Fractures of the Frontal Bone (4.) Loosening of the Horns (5.) Wounds and Injuries to the Skull (6.) Yoke-injuries in Working Oxen (7.) Trephining the Cranial Cavity in Sheep or Cattle, or Opening by the Trocar . . . . . PAGE 357 357 359 360 363 365 372 373 373 377 377 380 380 381 382 DISEASES OF THE NECK. I. Wounds and Bruises of the Tissues of the Neck . . 388 II. Fractures of the Cervical Vertebrae .... 391 III. Distortion of the Neck (Torticollis) .... 393 IV. Goitre, Struma ....... 401 V. Inflammation of the Bursa of the Ligamentum Nuch^e . . 406 VI. Phlebitis. Inflammation of the Jugular Vein . . . 409 VII. Diseases of the Pharynx and Oesophagus . . . 413 (1.) Foreign Bodies in the Pharynx and Oesophagus . . 413 (a) Foreign Bodies in the Pharynx and Oesophagus of the Horse 414 (b) Foreign Bodies in the Oesophagus of Cattle. 03sophagotomy 416 (c) Foreign Bodies in the Oesophagus of Swine . . 423 (d) Foreign Bodies in the Pharynx and Oesophagus of Carnivbra 424 (e) Impaction of the Crop in Birds .... 425 (2.) Injuries to the Pharynx and Oesophagus (Oesophageal Fistula) 426 (3.) Ectasise, Diverticula, and Ruptures of the Oesophagus . 427 (4.) Stenosis and Compression of the Oesophagus . . . 431 (5.) Paralysis of the Pharynx and Oesophagus . . .431 (6.) Tumours in the Pharynx and Oesophagus . . . 433 VIII. Diseases of the Larynx and Trachea .... 437 (1.) Injuries, Inflammation, and Tumours in the Larynx (Laryn- gitis. Perilaryngitis) ..... 437 (2.) Neuroses of the Larynx — Spasm of the Rima Glottidis — Laryngismus Stridulus — Hemiplegia and Diplegia Laryngis 442 (3.) Fracture, Deformity, and Stenosis of the Trachea . . 444 (4.) Foreign Bodies, Tumours, and Parasites in the Trachea . 447 (5.) Tracheotomy ...... 449 (6.) Laryngotomy ...... 460 CONTESTS. DISEASES OF TH E THORAX. I. Fractures of the Ribs — Fractur.e Costarum II. Costal Sinus ...... III. Sternal Sinus and Fracture of the Sternum IV. Wounds and Bruises of the Soft Parts of the Chest-Wall (1.) Wounds of the Chest- Wall without Perforation (2.) Wounds of the Pleura and Thoracic Cavity V. Shoulder Abscess ..... VI. Saddle and Collar Galls — Injuries from Pressure . (1.) Injuries Produced by the Saddle — Saddle-Galls, Fistulous Withers ...... (2.) Bruises Produced by the Collar or other Portions of the Harness VII. Tumours of the Breast ..... VIII. Tapping the Chest (Paracentesis Thoracis, Thoracocentesis) (1.) Puncture of the Thorax for Removal of Pleuritic Exudate (2.) Tapping the Pericardium in the Dog . PAGE 473 47.". 47(5 478 ITS 480 4S4 489 4S'.I 498 500 501 501 505 SURGICAL DISEASES OF THE ABDOMEN. I. Bruises of the Abdominal Walls II. Wounds of the Abdomen ..... III. Bowel Fistula (Anus Preternaturalis) . IV. Paracentesis Abdominis (Puncture of the Abdomen) V. Hernia ....... VI. Umbilical Hernia (Omphalocele, Exomphalos) . VII. Inguinal Hernia, Scrotal Hernia (Hernia Inguinalis, Herni Scrotalis) ...... (1.) Inguinal Hernia in the Horse (A) Treatment of Non-Strangulated Inguinal Hernia (B) Treatment of Incarcerated Inguinal Hernia (2.) False Inguinal Hernia (Interstitial Inguinal Hernia). (3.) Inguinal Hernia in Ruminants (4.) Perineal Hernia in Swine .... (5.) Inguinal Hernia in Dogs .... VIII. Crural Hernia (Hernia Cruralis) IX. Perineal Hernia ...... X. Ventral Hernia (Hernia Ventralis) XI. Pelvic Hernia, " Gut-Tie " . ... XII. Diaphragmatic Hernia (Hernia Diafjiragmatk ia) 508 510 517 518 520 530 538 539 543 547 550 552 553 555 556 558 559 564 566 CONTENTS. SURGICAL DISEASES OF THE STOMACH AND BOWELS. I. Foreign Bodies in the Digestive Tract . . . II. Puncture of the Bowel in Horses (Enterocentesis) III. Puncture of the Rumen and Rumenotomy IV. Intussusception or Invagination of the Bowel . V. Twist or Rotation of the Colon in Horses page 568 574 580 587 589 SURGICAL DISEASES OF THE POSTERIOR PORTIONS OF THE RECTUM AND OF THE ANUS. I. Congenital Malformations. Absence of the Anus and Forma- tion of Cloaca (Atresia Ani et Recti, Fistula Recto- Vaginalis) ....... 593 II. Injuries to the Rectum and Anal Region . . . 596 III. Inflammation of the Mucous Membrane of the Rectum and Anus (Proctitis) ...... 598 IV. Inflammation of the Connective Tissue surrounding the Rectum ....... 599 V. Prolapse of the Rectum and Anus (Prolapsus Recti et Ani) 601 VI. Contraction, Dilatation, Stenosis, and Paralysis of the Rectum and Anus ....... 608 VII. Anal Fistula and Recto- Vaginal Fistula . . .611 VIII. Tumours in the Rectum and Anus. Hemorrhoids . . 612 DISEASES OF THE URINARY ORGANS. I. Congenital Malformations (1.) Fissuring of the Male Urethra (Hypospadia and Epispadia) (2.) Pervious Urachus II. Urinary Calculi .... (1.) Urinary Calculi in the Horse — Lithotomy (2.) Urethral Calculi in Ruminants — Urethrotomy (3.) Urinary Calculi in Swine (4.) Urinary Calculi in the Dog III. Puncture of the Bladder (Punctio Vesica) IV. Injuries, Inflammation, and Strictures of the Urethra V. Paralysis of the Urinary Bladder (Cystoplegia). Catheterism VI. Inflammation of the Urinary Bladder (Cystitis) VII. Prolapse, Retroflexion and Inversion of the Urinary Bladder VIII. Tumours in the Urethra and Bladder , 615 615 615 616 617 625 630 631 633 635 638 641 643 647 CONTENTS. DISEASES OF THE MALE ORGANS OF GENERATION. I. Inflammation of the Prepuce (1.) Inflammation of the Prepuce in the Horse (2.) Inflammation of the Prepuce in Oxen (3.) Inflammation of the Prepuce in Swine (4.) Inflammation of the Prepuce in Carnivora II. Phymosis, Paraph ymosis, Paralysis of the Muscles of the Penis Injuries to the Penis III. Amputation of the Penis . IV. Tumours of the Sheath and Penis V. Diseases of the Prostate VI. Diseases of the Scrotum . AND VII. Inflammation of the Testicle Periorchitis, Epididymitis Epididymis. Orchitis VIII. Tumours of the Testicle (Sarcocele) and of the Epididymis IX. Hydrocele, Hematocele, and Varicocele X. Inflammation of the Spermatic Cord. Scirrhous Cord Funiculitis Chronica ..... PAOE 651 651 653 655 655 656 665 666 670 671 673 675 DISEASES OF THE FEMALE ORGANS OF GENERATION. I. Injuries and Inflammation of the Vulva, Vagina, and Uterus II. Prolapse (Inversion) of the Vagina III. Prolapse (Inversion) of the Uterus IV. Tumours of the Vagina and Uterus V. Diseases of the Mammary Gland .... (4.) (5.) (6.) (7.) (8.) (9.) (10.) (11.) Wounds and Bruises of the Udder and Teats. Lacteal Calcu Acute Inflammation of the Udder. Its Pathology and Varieties ..... Acute Mammitis .... (A) Interstitial Mammitis. Lymphogenous Mastitis (B) Parenchymatous Mammitis. Catarrhal Mastitis Chronic Mammitis Contagious Mammitis. Gangrenous Mammitis of Milch Ewes. Tuberculosis of the Udder Actinomycosis of the Udder . Botryomycosis of the Udder . Stenosis and Closure of the Teat Dud Tumours of the Udder 682 686 (iSil 694 698 699 701 704 704 705 709 709 712 713 714 714 716 719 CONTENTS. DISEASES OF THE SPINAL COLUMN AND PELVIS. PAGE I. Fractures, Luxations, and Sub-Luxations of the Dorsal and Lumbar Vertebrae. Commotio Spinalis . . .721 II. Fractures of the Sacral and Caudal Vertebra . . 726 III. Curvature of the Spine ...... 728 IV. Fractures of the Pelvis . . . . . .731 V. Diastasis or Luxation of the Sacro-Iliac Articulation . . 739 VI. Luxation of the Symphysis Ossium Pubis . . . 741 VII. Hygroma of the Subcutaneous Bursa of the Tuber Ischii in Cattle ........ 742 VIII. Paralysis of the Hind Extremities. Paraplegia . . 742 IX. Diseases of the Tail . . . . . .751 X. Necrosis of the Lumbo-Dorsal Fascia .... 757 DISEASES OF THE FORE LIMB. A. DISEASES OF THE SHOULDER REGION. I. Fractures of the Scapula. ..... 759 II. Fractures of the Humerus . . . . .762 III. Diseases of the Shoulder- Joint ..... 765 IV. Inflammation of the Bursa of the Biceps, Flexor Brachii or Coraco Radialis Muscle (Bursitis Intertubercularis) . 769 V. Inflammation of the Tendon of the Postea-Spinatus Muscle and of its Bursa ...... 771 VI. Paralysis of the Suprascapular Nerve .... 772 VII. Paralysis of the Radial Nerve (Paralysis Nervi Radialis) . 775 VIII. Paralysis of the Brachial Plexus .... 782 IX. Shoulder Lameness ...... 783 B. DISEASES OF THE ELBOW AND FORE ARM. I. Fracture of the Ulna II. Fracture of the Radius . III. Luxation of the Elbow-Joint IV. Inflammation of the Elbow-Joint V. Capped Elbow in the Horse VI. Wounds and Bruises of the Fore Arm 789 790 792 793 794 800 C. DISEASES OF THE KNEE. I. Fractures of the Bones of the Knee .... 802 II. Injuries to the Anterior Surface of the Knee . . . 804 (1.) Injuries to the Knee in the Horse .... 804 (2.) Hygroma of the Knee in Cattle . . . .809 III. Chronic Inflammation of the Knee-Joints . . . 812 IV. Distension of Articular and Tendinous Synovial Cavities in the Fore Limb ....... 814 V. Inflammation of the Synovial Sheath of the Carpal Arch . 823 CONTENTS. D. DISEASES OF THE METACARPUS. I. Fractures of the Metacarpus .... II. Wounds and Bruises of the Metacarpus III. Rupture of the Flexor Tendons and Suspensory Ligament IV. Inflammation of the Flexor Tendons (Tendinitis) and of the Suspensory and Check Ligaments V. Knuckling in Foals ..... VI. Bent Knees in Horses ..... VII. Splints ....... E. DISEASES OF THE FETLOCK AND DIGIT. I. Luxation of the Phalanges II. Fractures of the Phalanges III. Fractures of the Sesamoid Bones IV. Se amoid Lameness V. Ring-Bone Plantar Neurectomy Median Neurectomy Ulnar Neurectomy VI. Sprain of the Coronary Joint VII. Ossification of the Lateral Cartilage. Side-bone VIII. Fracture of the Navicular Bone IX. Navicular Disease X. Dermatitis in the Fetlock Region. Mud-Fever — Cracked Heels — Grease (a) Dermatitis Erythematosa (b) Dermatitis Eczematosa (c) Dermatitis Gangrenosa (d) Dermatitis Chronica Verrucosa DISEASES OF THE HIND LIMB. A. DISEASES OF THE QUARTER. I. Injuries to the Muscles and Fascle of the Quarter II. Fracture of the Femur ..... III. Luxation of the Femur ..... IV. Inflammation of the Hip-Joint (Coxitis) V. Inflammation of the Bujrsa of the Gluteus Medius Tendon. Bursitis Glutei Medii ..... VI. Paralysis of the Hind Limb .... A. Paralysis of the Gluteal Nerves B. Paralysis of the Great Sciatic Nerve C. Paralysis of the External Popliteal Nerve D. Paralysis of the Crural Nerve .... E. Paralysis of the Obturator Nerve VII. Thrombosis of the Posterior Aorta and of its Br\nches VIII. Displacement of the Biceps Femoris Muscle IX. Hip Lameness ...... CONTENTS. B. DISEASES OF THE STIFLE-JOINT. I. Luxation and Sprain of the Femoro-Tibial Joint II. Displacement of the Patella (a) Upward Luxation .... (b) Lateral Luxation .... III. Rupture of the Straight Ligaments of the Patella IV. Fracture of the Patella V. Injuries and Acute Inflammation of the Stifle-Joint. Gonitis VI. Chronic Inflammation of the Stifle-Joint. (Gonitis Chronica Sicca) ........ VII. Bursitis Pr^epatellaris .... page 957 958 958 962 964 964 966 968 970 C. DISEASES OF THE LOWER THIGH OR LEG. I. Wounds and Injuries . . . . . .971 II. Fracture of the Tibia ...... 972 III. Rupture of the Tibio-Fibular Interosseous Ligament . . 976 IV. Rupture of the Tendinous Flexor Metatarsi . . . 976 V. Rupture of the Tendo Achillis and Gastrocnemii Muscles . 980 D. DISEASES OF THE HOCK. I. Fracture of the Bones of the Hock II. Luxation and Sprain of the Hock-Joint III. Wounds and Acute Inflammation of the Hock-Joint . IV. Bog-Spavin. Chronic Synovitis of the Tibio-Tarsal Joint V. Chronic Inflammation of the Hock. Spavin. Arthritis Chronica Deformans Tarsi VI. Enlargements on the Outer Surface of the Hock VII. Curb ...... VIII. Capped Hock ..... IX. Luxation of the Flexor Pedis Perforatus Tendon X. Stringhalt ..... XI. Shivering ...... 984 986 987 989 992 1013 1014 1017 1020 1021 1027 E. DISEASES OF THE METATARSUS. I. Diseases of the Tendons and Tendon Sheaths in the Tarsal and Metatarsal Regions ..... 1029 II. Suppurative Inflammation of the Sesamoid Synovial Sheath of the Flexor Tendons ...... 1036 III. Injuries produced by Striking (Interfering) and their Compli- cations ........ 1039 b 2 CONTENTS. F. DISEASES OF THE FOOT. (A) Acute Inflammation of the Keratogenous Membrane. Pododer matitis Acuta ...... I. Pricks or Stabs in Shoeing .... II. Picked-up Nails. Purulent Cellulitis of the Plantar Cushion Resection of the Flexor Pedis Perforans III. Treads and Injuries to the Coronet. Purulent Inflammation OF THE SUBCORONARY CONNECTIVE TISSUE IV. Corns ....... V. QUITTOR ....... VI. Laminitis. Inflammation of the Sensitive Laminae VII Keratoma ...... VIII. Canker of the Sole and Frog (Pododermatitis Chronica Ver rucosa vel Migrans) ..... ( PAGE 1043 1051 1052 1058 1064 10G7 1079 1086 1090 G. DISEASES OF THE CLAWS IN CATTLE AND SHEEP. I. Bruises of the Sensitive Sole and Bulbs of the Foot in Oxen 1098 II. Wounds of the Soft Tissues of the Claw . . . 1100 III. Laminitis in Oxen ...... 1100 IV. Panaritium, Whitlow of the Claw .... 1101 V. Amputation of the Claws in Oxen .... 1105 VI. Abnormalities of the Horny Claw .... 1109 VII. Foot-Rot in Sheep . . . . . .1109 H. DISEASES OF THE CLAWS IN CARNIVORA. I. Growing-in of the Claws (Incarnatio Unguis). Dislocation of the Claws. Chronic Inflammation of the Claw Matrix. Loss of the Claws . . . . . .1111 II. Bruises and Wounds of the Pads of the Sole and Toe . . 1113 Index 111; LIST OP ILLUSTRATIONS. FIG. 1. The blinds 2. The hood or cap 3. Twitch . 4. " Bulldogs " 5. Leg-twitch 6. Loop-twitch 7. Loop-twitch tightened 8. Bull-holder 9. Bull-holder 10. Nose-ring 11 & 12. Bull-leaders 13. Application of nose-ring 14. Varnell's mouth-gag 15. Bayer's mouth-gag 16. Bayer's mouth-gag for dogs 17. Joger's mouth-gag 18. Woolf's mouth-gag 19. Woolf's mouth-gag 20. Haussmann's mouth-gag 21. Rubber-covered plates for mouth-gag 22. Haussmann's gag (closed) 23. Gray's mouth-gag for dogs 24. Pulling-up fore leg 25. Tying-up fore leg 26. Fastening fore and hind pasterns together 27. Pulling-up a hind foot . 28. Hippo-lasso 29. Hippo-lasso applied 30. Hippo-lasso in operation 31. Securing hind legs to prevent kicking 32. Securing bullock's hind legs 33. Securing one hind foot for shoeing 34. Fastening a cow for operation . 35. The side-stick 36. The cradle or " beads " 37. Daviau's operating table 38. Daviau's table in operation 39. Model operating table . 40. Horse in position for operation . 41. Casting horse with a cart-rope LIST OF ILLUSTRATIONS. FIG. 42. The hobbles 43. Cross-hobbles 44. Hobbles applied 45. Hobbles applied with apparatus to prevent broken buck 46. Casting horse (Stuttgart method) 47. Hobble-key 48. Apparatus to prevent broken back 49. Horse cast and secured . 50. Showing method of fastening hind legs 51. Horse cast and tied 52. Horse secured for castration 53. Another method 54. Fastening a hind to a fore leg . 55. Fastening a hind to a fore leg, with application of leg 56. Mode of fastening fore and hind limbs together 57. Castration in dorsal position 58. Fixing horse for operation (Berlin method) 59. Casting horse (Russian method) 60. Russian method of single-handed casting 61. Russian method of single-handed casting (hoist' down) 62. Casting an ox (first position) 63. Casting an ox (second position) 64. Bernard's operating- table for dogs 64a. All-metal operating table for small animals 65. Cox's chloroform muzzle 66. Carlisle's chloroform muzzle 67-72. Scalpels 73. Dissecting-forceps 74. Curved scissors (aseptic joint) . 75. Curved scissors (aseptic joint) . 76. Straight scissors (aseptic joint) . 77-79. Retractors 80-81. Lion forceps . 82. Steam steriliser . 83. Steam steriliser . 84. Silk-holder 85. Portable silk-holder 86. Sealed-tube for silk 87. Sealed-tube for silk 88. Drainage-tubes in holder 89. Irrigator for hospital use 90. Irrigator, portable 91-97. Methods of holding Knives . 98. Making an incision 99, 100. Making incisions . 101. Director .... 102-103. Chassaignac's ccraseur 104. Dewar's ecraseur 105,106. Methods of holding knives . twitch. LIST OP ILLUSTRATIONS. XX111 FIG. 107. Method of holding scissors 108. Holding scalpel and director 109. 110. Holding scalpel and director 111. Elastic ligature applied 112. Extent of contraction of ligature 113. 114. Paquelin's thermo-cautery . 115-119. Platinum heads for Paquelin's cautery 120, 121. Holding scalpel when puncturing 122. Holding a suture needle . 123. Trocar for chest 124. Trocar for bowel 125. Trocar for rumen 126. Bone chisel 127. Bone gouge 128. 129. Curettes 130. Flushing curette 131. Bone forceps 132. Frame bone-saw 133. Chain saw 134. Largu's suture-needle 135. De Mooij's suture-needle 136. 137. Reiner's needle-holder 138. Hagedorn's needle-holder 139. Suture needles . 140. Interrupted suture 141. Inserting the suture 142. Methods of suturing 143. Glover's suture . 144. Pin suture 145. Interrupted suture 146. Quilled suture . 147. Sutures of relaxation 148. Tension suture in position 149. 150. Jobert's suture 151. Lembert's bowel-suture . 152. Lembert-Czerny bowel-suture 153. Tourniquet 154. Catch for rubber tourniquet 155. Ligating an artery (first stage) 156. Ligating an artery (second stage) 157. Greig-Smith's artery forceps 158. Spencer Well's artery forceps 159. 160. Aneurysm needles . 161. Restoration of blood supply by collateral vessels 162a, 162b. Acupressure methods 163. Rolling a bandage 164. Two-ended bandage 165. Machine for rolling bandages 166. 167. Bandaging . XXIV LIST OF ILLUSTRATIONS. FIG. 168-173. Bandages . 174-179. Bandages . 180-185. Bandages . 186-191. Bandages 192-195. Bandages , 196. Lancets for venesection . 197-200. Fleams 201. Bleeding-stick . 202, 203. Spring-fleams 204,205. Bleeding with spring-fleam 206. Bleeding with lancet 207. Bleeding with fleam 208. Dieckerhoff's bleeding-cannula 209. Scarificator 210. Line firing-iron 211. Bud, point, line, and disc firing- 212. Needle firing-iron 213. Degive's needle-firing apparatus 214. Degive's needle-firing apparatus 215. Zoo-cautery 216. Dechery's automatic cautery 217. Automatic furnace 218. Pattern for line-firing . 219. Positions in which setons may 220. Seton needle 220a. Bent seton needle 220b. Jointed seton needle . 221. Rowelling scissors 222. Sick's inoculating needle 223. Pessina's inoculating needle 224. Sticker's inoculating needle 225. 226. Sterilisable syringe 227. Roux's sterilisable syringe 228. Double acting syringe . 229. Transverse section of neck 230. Togl's forceps . 231. Kaiser's forceps 232. Holler's forceps 233. Bayer's forceps 234. Robertson's forceps 235. Bayer's forceps in use 236. Forceps for clams 237. Wooden clams . 238. Iron clams 239. Screw for closing clam 240. Raising the testicles 241. Holding the testicles 242. Holding tile testicles 243. Applying the clam eady for use be inserted List op illustrations. xxV 244. Section of inguinal canal 245. Transverse section of prepubic region 246. Abdominal cryptorchidism 247. Internal inguinal region 248. Prepubic region seen from below 249. Transverse section of posterior abdominal region 250. Inguinal incision .... 251. Transverse section of posterior abdominal region of mare 252. Transverse section of posterior abdominal region of cow 253. Longitudinal section (mare) 254. Longitudinal section (cow) 255. Charlier's vaginal speculum 256. Charlier's vaginal (later form) 257. Guarded bistoury 258. Ovariotomy in the cow (first stage) 259. Ovariotomy in the cow (second stage) 260. Scissors for ovariotomy 261. Forceps for ovariotomy . 262. Forceps for ovariotomy . 263. Metal finger-stall 264. Finger clamps . 265. Colin' s guarded bistoury 266. Colin's ovariotomy forceps 267. Ovariotomy (Cadiot's method) 268. Grasping the ovary (cow) 269. Atheroma of the false nostril 270. Right-sided facial paralysis (central) 271. Double-sided facial paralysis (peripheral 272. Position of nostrils and nose in double-sided (peripheral) facial paralysis 272a. Electric torch 273. Supernumerary tooth (horse) 274. Normal position of the molars in the horse 275. Tooth rasp 276. 277. Tooth chisels 278. Tooth cutter 279. Left-sided shear-mouth . 280. Grinding surfaces in shear-mouth and in normal mouth 281. 282. Tooth shears 283. Tooth screw 284. Metznik's tooth shears - . 285. Central dry caries of a horse's upper molar 286. Scalers for dogs' teeth Necrosis of a dental alveolus, with displacement of the last molar and extensive ostitis of the lower jaw (horse) Giinther's forceps for upper molars Gunther's forceps for lower molars 290. Gunther's exporteur 291. Giinther's beaked forceps 292. Gunther's forceps for first lower molars 287. 288. 289. LIST OF ILLUSTRATIONS. PIG. 293. Gunther's forceps for first upper molars . 294. Frick and Hauptner's " Universal " forceps 295. Showing the incisor and molar teeth of a six year old horse in position 296. Gunther'a tooth pickers ..... 297. Fulcra ....... 298. Gunther's forceps for the incisors 299. Ordinary forceps for the incisors 300-302. Dental forceps for dogs .... 303. Periostitis alveolaris ossificans of the third molar (horse) . 304. Epulis in a mastiff ; showing deformity of face and upper jaw 305. The same ; interior of the mouth 306. Facial oedema after injury .... 307. Osteomata from skull of a three year old bullock 308. Stock trephine . ..... 309. Hand trephine ...... 310. Bone screw ...... 310a. Elevator ...... 311. Chisel ....... 312. Lenticular knife ..... 313. Periosteum knife ..... 314. Exfoliative trephine ..... 315. Perforating trephine ..... 316. Head of a horse (B) . 317. Lateral view of horse's skull ; the facial sinuses exposed . 318. Necrosis of the turbinated bones 319. Infero-lateral view of the laryngeal region (B) . 320. Parotid gland and Stenson's duct. (Semi-schematic.) (C) 321. Actinomycosis of the parotid gland in an ox . 322-325. Plastic operations (B) . 326. Incomplete union of fracture of the body of the lower jaw . 327. Fracture of the lower jaw united by wiring (C) . 328. Cancer of the inferior maxilla .... 329. Botryomycosis of the lower jaw .... 330. Osteoporosis of the upper jaw . 331. Pre-auricular fistula due to presence of a dentigerous cyst 332. Gunther's catheter ..... 333. Deep tissues in the parotid region ; opening the guttural pouche (Semi-schematic.) (C) .... 334. Splint for fracture of horn core .... 335. Form of splint for fracture of horn core . 336. Zehden's syringe ..... 337. Zehden's trocar ..... 338. Sub-luxation of the 3rd cervical vertebra, as seen from the left side 339. Sub-luxation of the 3rd cervical vertebra, as seen from the right side 340. Distortion of the neck (torticollis) in consequence of the calkin of a hind shoe becoming caught in the head-collar 341. Knudsen's iron splint for distortion of the neck . 342. Probang and mouth gag for cattle 343. (Esophageal ..... 396 400 418 419 LIST OF ILLUSTRATIONS. XXV11 no. 344. (Esophageal screw ...... 345. Delvos and Hertwig's oesophageal forceps 346. To illustrate the operation of cesophagotomy. (Semi-schematic.) (C) 347. Section at right angles to the long axis of the neck through the upper third of the sixth cervical vertebra (E) 348. A papilloma from the oesophagus of an ox 349. Tampon-cannula, or Trendelenberg-cannula 350. Hayne's tracheal trocar 351-353. Thompson's tracheotome 354. Making the incision in tracheotomy (B) 355. Introducing the cannula (B) 356. Method of performing tracheotomy 357. Barthelemy's cannula .... 358. Position of tracheal cannula 359. Leblanc's jointed cannula 360. Leblanc's jointed cannula 361. Peuch's cannula .... 362. Field's tracheotomy tube 363. Coleman's tracheotomy tube 364. Double-tube cannula . - . 365. Superior orihce of the larynx and glottis of a horse affected with chronic roaring ..... 366. Moller's operation. Vertical and antero-posterior section of the larynx 367. Scalpel for resection of arytenoid 368. Course of incision (horse's larynx) 369. Curved scissors .... 370. Forceps for grasping the arytenoid 371. Curved needle for suturing laryngeal mucous membrane 372. Spring hooks ..... 373. Trendelenberg cannula 374. Arytenoidectomy. Second phase of the operation 375. Third phase (a). Incision of mucous membrane 376. Third phase (b). Section of vocal cord . 377. Third phase (b). Dissection of arytenoid 378. Third phase (c). Division of arytenoid 379. Third phase (d). Excision of arytenoid. 386. Fourth phase. Suture .... 381. Termination of the suture 382. Superior opening of the larynx and glottis of a " roarer " that died of pneumonia eighteen days after the operation . 383. Pulveriser for disinfecting the laryngeal wound . 384. Antero-posterior section of the preceding larynx 385. Multiple abscess formation in the shoulder- region due to Botryomyces (C) 386. Transverse section through horse's thorax. (Semi-diagrammatic, after Franck.) ..... 387. Dieulafoy's aspirator .... 388. Special trocar and cannula 389. 390. Showing mechanism of incarceration of intestine 391. Kiihn's needle for ligation of the sac in umbilical hernia XXV111 LIST OF ILLUSTRATIONS. FIG. 392. Bordonnat's clam ...... 393. Combe's clam ....... 394. Incomplete inguinal hernia ..... 395. Inguinal hernia of the hor.se ..... 396. Herniotome ....... 397. Herniotome ....... 398. Peritoncal-scrotal hernia ..'... 399. Ventral hernia in a mare ..... 400. Schema illustrating Degive's operation for umbilical and ventral hernise 401. Anker's guarded knife for pelvic hernia. .... 402. Diaphragmatic hernia ...... 403. Gely's bowel suture ...... 404. Lembert's bowel suture ..... 405. Wolfler's bowel suture . ..... 406. Lembert's bowel suture ...... 407. Czerny's bowel suture ...... 408. Vertical section of the horse's body between the last rib and external angle of the ilium ...... 409. Friedberger's intestinal trocar for horses .... 410. Showing the relative positions of the thoracic and abdominal organs. Left side ....... 411. Showing the relative positions of the thoracic and abdominal organs. Right side ....... 412. Abdominal organs seen from below (L) . 413. Mouth gag for oxen ...... 414. Trocar and cannula for puncture of the rumen . 415. Vertical section of the ox's body, showing relative position of rumen and other organs ...... 416. Brauer's trocar ...... 417. Forceps for use with Brauer's trocar .... 418. Sheath of Brauer's trocar ..... 419. Congenital malformation — atresia ani in the bitch. (Semi-diagrammatic.) 420. Congenital malformation — atresia ani et recti in the bitch. (Semi- diagrammatic.) ...... 421. Prolapsus recti with invagination in the bitch. (Semi -diagrammatic.) 422. Prolapsus recti with invagination in the horse 423. Stockfleth's wooden ring ..... 424. 425. Method of ligation in prolapsus recti .... 426. Calculus passed spontaneously. Natural size 427. Urethral obstruction removed by Mr. Mellis 428. Vaginal speculum ...... 429. Calculus spoon ....... 430. Calculus forceps ...... 431. Bouley's calculus forceps ..... 432. Vesical calculus composed of phosphate and oxalate of lime . 433. Cystic calculus removed by V. -Major Walker 434. Section of calculus removed by V. -Major Walker 435. Course of the urethra in the ox . 436. Flourant's trocar ...... LIST OF ILLUSTRATIONS. FIG. 437. 438. 439. 440. 441. 442. 443. 444. 445. 446. 447. 448. 449. 450. 451. 452. 453. 454. 455. 456. 457. 458. 459. 460. 461. 462. 463. 464. 465. 466. 467. 468. 470. 471. 472. 473. 474. 475. 476. 477. 478. 479. 480. Median section of the bladder, urethra, vagina, and vulva of a cow (B) Inversion of the bladder in a mare Amputation of the penis by the elastic ligature . Amputation of the penis showing stump and urethral orifice Carcinoma of the testicle in a horse Scirrhous cord formation in the horse . Prolapse (inversion) of the vagina Simple vaginal speculum Expanding vaginal speculum (closed) Expanding vaginal speculum (open) Milk fistulae, method of suturing Fracture (by crushing) of the body of a vertebra (C) Bernadot and Butel's apparatus for prevention of broken back when casting ..... Schema illustrating fractures of the pelvis in the horse Docking knife ..... Docking knife ..... Amputation of tail by flap operation (B) Amputation of tail by flap operation, second stage (B) Amputation of tail by flap operation, third stage (B) Amputation of tail by flap operation, fourth stage (B) Total necrosis of the scapula Fracture of the humerus Lameness from bursitis intertubercularis Fractured first rib . Complete paralysis of the radial nerve First portion of the stride in a case of paralysis of the radial nerve (C) Fracture of the ulna in a horse . Capped elbow ..... Hygroma of the knee resulting from bruising . Plastic operation for removal of scars from the knee (B) Plastic operation for removal of scars from the knee (operation completed) (B) • Plastic operation for the removal of scars from the knee (the knee two months after operation) (B) . Knee tumour (cutaneous form) . Distension of the extensor pedis and flexor sheaths Schema of the more important tendon sheaths or bursae of the fore limb seen from in front and without The same, as seen from the front Outer surface of the fore limb ; to show synovial sheaths (L) Inner surface of the fore limb ; to show synovial sheaths (L) Showing relative positions of tendons, &c, in the metacarpal region (C) Rupture of the flexor pedis perforans and perforatus tendons (C) Rupture of the flexor pedis perforans behind the fetlock in consequence of suppuration in the tendon sheath . Rupture of the superior sesamoid or suspensory ligament Excessive knuckling in a horse .... Section through the centre of the metacarpus . XXX LIST OF ILLUSTRATIONS. FIG. PA OS 481. Tenotomy— first stage (B) . . . . .847 482. Tenotomy — second stage (B) . . . . . . 847 483. To illustrate the peculiar gait alter tenotomy .... S4S 484. Excessive dorsal flexion after section of the perforans and perforates tendons ........ 849 485. Special shoe for knuckling . . . . . .850 4N(>. Double-sided knuckling in a two year old colt .... 852 487. Friebel's extension apparatus ...... 853 488. Perpendicular mesial section of right fore foot .... 863 489. 490. Superficial and deep ligaments of the fetlock, pastern, and navicular joints ........ 865 491. Fracture of os suffraginis ...... 868 492. Fracture of os suffraginis with formation of exostosis . . . 868 493. Transverse fracture of os suffraginis ..... 868 494. Double fracture of upper end of os suffraginis .... 868 495. Longitudinal fracture of os suffraginis ..... 868 496. Articular ring-bone ....... 877 497. Periarticular ring-bone ...... 877 498. The outside of the right coronet shows ring-bone formation ; the left is normal ........ 878 499. Showing course of internal plantar nerve .... 883 500. Section through the metacarpus about 3 to 4 inches above the fetlock- joint (E) ........ 884 501. Section through the fetlock-joint ... . . . . 884 502. Neurectomy below the fetlock ..... 885 503. Neurectomy above the fetlock . . . . . .886 504. Section through the fore arm, near the bottom of the upper fourth of the radius (E) ...... . 888 505. Showing course of median and ulna nerves . . . . SS<| 506. Median neurectomy. (Semi-diagrammatic.) .... 890 507. Operation of median neurectomy. The nerve exposed . . . 891 508. Section of " neuroma " from the divided end of the median nerve, three months after operation ...... 891 509. Longitudinal section of the median nerve, 6 inches below the point at which neurectomy was performed . . . . .891 510,511. Neurectomy of the ulnar nerve ..... 893 512. The flexors perforans and perforatus in a case of sesamoid lameness . 874 513. Showing lateral cartilages and their attachments . . . 899 514. Right fore foot ....... 899 515. Pedal bone, with almost complete ossification of the lateral cartilages . 900 516. Preparation illustrating navicular disease . . . .904 517. Navicular bone in chronic navicular disease .... 905 518. Flexor pedis perforans tendon in chronic navicular disease . . 906 519. Straight seton needle . . . . . . .912 520. Curved seton needle . . . . . . .912 521. Paralysis of the anterior crural nerve (C) . . . . 937 522. Paralysis of internal popliteal nerve ..... 938 523. Paralysis of tin- external popliteal nerve .... 941 524. Incomplete crura paralysis ...... 944 969 977 978 979 LIST OF ILLUSTRATIONS. XXXI fig. P AtiE 525. Biceps femoris muscle . . . . . • .951 526. Left-sided chronic inflammation of the stifle-joint (Gonitis chronica) . 969 527. Bilateral chronic inflammation of the stifle-joint (Gonitis chronica bilateralis) ......•• 528. Rupture of the flexor metatarsi (C) 529. Showing the mechanism of the hock and stifle-joints (L) . 530. Rupture of the flexor metatarsi tendon . 531. Rupture of the tendo Achillis (C) . . . • • 981 532. Rupture of the tendo Achillis in cow . .. ... • 982 533. Exuberant granulation in front of the hock . 988 534. Spavin formation on left hock (seen from in front) . . .991 535. Spavin formation on right hock (seen from behind) . . • 991 536. Operation for division of the cunean tendon of the flexor metatarsi muscle (C) ....... • 1005 537. Periosteotomy knives ....... 1007 538. Horizontal section through the hind limb about the lower quarter of the tibia (E) 1008 539. Rubber cord applied to thigh to check bleeding . 1009 540. 541. Neurectomy of the anterior tibial nerve . 1010 542. Showing relations of the posterior tibial nerve (B) . • • 1011 543. Neurectomy of the posterior tibial nerve (B) . 1012 544. Curb ......... 1015 545. Capped hock (dropsy of the subcutaneous bursa of the hock) . ■ 1018 546. Stringhalt (C) ....... 1024 547. Tendon sheaths and bursa? of the hind limb of the horse, seen from without. (Semi-diagrammatic) . 1030 548. Tendon sheaths and bursae of the hock- joint, seen from within. (Semi- diagrammatic.) ....... 1030 549. External surface of the horse's hock, to show synovial sheaths (L) . 1031 550. Internal surface of the horse's hock, to show synovial sheaths (L) 1032 551. Distension of bursa of flexor tendon in right hock . . • 1033 552. Distension of sheath of flexor pedis perforans . 1033 553. Distension of the metatarso-phalangeal (sesamoid) sheath (C) . . 1034 554. Enlargement of the bursa of the extensor pedis tendon (C) . • 1036 555. Position of the limb, in suppurative inflammation of the sesamoid sheath in the pastern ....... 1037 556. Rupture of the flexor pedis perforans tendon .... 1038 557. To illustrate the superficial structures involved in surgical injuries of the foot 1046 558. To illustrate the deeper-seated structures involved in surgical injuries of the foot . . . . . . . 1046 559. To illustrate the joints and deep-seated arteries, veins, and nerves involved in surgical injuries of the foot .... 1047 560. Vertical cross section of foot ...... 1048 561. Vertical cross section of foot ...... 1048 562. Cross section of a sound and well-shod hoof, showing the proper position of the nails ........ 1051 563. Operation for partial resection of the aponeurosis of the flexor pedis perforans tendon (C) ...... 1053 LIST OF ILLUSTRATIONS. FIG. 564. 565. 566. 567. 568. 569. 570. 571. 572. 573. 574. 575. 576. 577. 578. 579. 580. 581. 582. 583. 584. PAGE Operation for complete resection of the aponeurosis of the flexor pedis perforans tendon (C) ...... 1053 Lateral view of fore foot, with nerves and injected vessels, showing some of the structures involved in inflammation of the sub-coronary connective tissue, and its complications .... 1063 Three-quarter bar shoe ...... 1065 Ordinary three-quarter shoe ...... 1065 Showing the lateral cartilage and its relations (L) . . . 1066 Hoof knives and knives for excision of lateral cartilage . . .1072 Operation for quittor (C) ..... 1073 Celluloid injection preparation of the veins and arteries of the foot prepared by maceration (B) . . . . . 1074 Bayer's operation (first stage) ..... 1077 Bayer's operation (second stage) ..... 1077 Bayer's operation (third stage) ..... 1078 Bayer's operation (fourth stage) ..... 1078 Longitudinal section of hoof three months after attack of laminitis . 1082 Longitudinal section of hoof one year after severe attack of laminitis . 1082 Hoof after laminitis ....... 1085 Hoof after laminitis (shod) ...... 1085 Portion of the inner surface of the wall showing changes after old- standing corn ....... 1088 Vertical section of an ox's claw ...... 1097 An ox's claw ........ 1106 Disarticulation of the ox's claw. Primary incision (C) . . . 1107 Disarticulation of the ox's claw (C) . . . . . 1108 In the above list the added letters have the following signification : (B), from Bayer's " Operationslehre " ; (C), from Cadiot and Almy's " Traite. de Therapeutique Chirurgicale " ; (E), from Ellenberger and Baum's " Anatomic " ; and (L), from Leisering's " Atlas." Most of these figures have been redrawn. REGIONAL- VETERINARY SURGERY AND OPERATIVE TECHNIQUE. I.— GENERAL REMARKS ON OPERATIONS. The word operation covers all mechanical interference under- taken for surgical purposes. Perfect restoration of function being usually demanded in veterinary surgery, many operations common in human practice must either be renounced or very seldom performed, partial recovery being worse than useless from the owner's standpoint. It is therefore often necessary to consider whether operation is justified or whether slaughter be not preferable. Owners as a class have quite erroneous impressions of the results to be expected. Many are not satisfied even when the animal's usefulness is completely restored because perhaps a trifling blemish remains. Some seem incapable of understanding that a certain time is necessary for recovery. They imagine that healing can be forced, become impatient, and in a few moments destroy by clumsy interference, or too early use of the animal, the results of weeks of skill, after- wards seeking to hold the operator answerable. In veterinary surgery the conditions for rapid healing are much less favourable than in human practice. The unsatisfactory sanitary surroundings, the active opposition of the animal, and frequently the impossibility of shielding the wound from injurious external influences, as in human surgery, often render success imperfect even with the greatest care and attention to detail. Division. Operations are divided according to varying circum- stances. Those requiring the use of the hands alone are sometimes known as manual operations ; the terms dressing and instrumental operations explain themselves. We speak also of elementary or compound, bloodless or sanguinary, regular or irregular ; of urgent 2 PLANNING THE OPERATION. operations and operations which may be deferred ; of operations on the skin, the muscles, bones, tendons, and so forth ; operations on the head, neck, trunk, etc., names which require no explanation. Urgent operations are such as cannot be postponed without gravely endangering life. The indications and contra-indications for operation must be carefully studied. Beginners are not infrequently over hasty in this respect. For instance, they declare an operation indispensable ; the owner refuses his consent, and nevertheless recovery results under simple treatment, or even without any treatment at all. The cliniques are perhaps somewhat to blame for this, as only severe cases which must be operated on are usually brought there, and even though in each case the special grounds which render operation indispensable are set forth, the student is apt to retain only a general impression, such as of a tumour and of the subsequent operation, forgetting the explanatory remarks. Such mistakes are made at first by everyone. Except in the case of urgent operations, like tracheotomy for threatening suffocation, operation for strangulated hernia, removal of a foreign body, etc., it is first necessary carefully to consider whether the animal's value, its chance of perfect recovery, and the probable duration of its convalescence, justify operation at all. The need for operation and the clangers it implies must be clearly placed before the owner. A wise practitioner, however, will not, except in very urgent circumstances, insist on immediately operating for fear of prejudicing his client, but after a moderate expression of opinion will wait, knowing that the failure of other means will finally force the owner himself to demand operation. Definite promises should never be made in order to gain the owner's consent, for, considering the extreme variability of wound-healing, results can never be foretold with absolute certainty. When surgical treatment can only have a temporary good effect and the disease is likely to return, when improvement is only to be obtained by sacrificing the animal's usefulness, or when the patient is old, or its strength is too greatly reduced, the practitioner's duty to his client is clearly to deprecate operation even if called upon to perform it. In the last connection dogs suffering from malignant disease are often submitted for operation in an extremely emaciated state. Should they die under the operator's hands the fact is related to the surgeon's discredit without any reference to the other circumstances. Planning the Operation. Before performing any operation the operator should mentally enact the details of each of the proposed stages. This mental process is unconsciously performed before the PREPARATION OF THE PATIENT. 3 simplest operation, but only when rare and difficult operations are projected does its necessity force itself on our recognition. In very difficult cases operation may previously be performed on the dead body and the anatomical relations noted. During the process one also determines the method of operation, for one method does not suit every case and it must be left to the ability of the operator to select the method he regards as being the best suited to the case in hand, the simplest to practise and as promising the desired result in the shortest time. Circumstances arising during the operation itself often necessitate unforeseen modi- fications, and test to the utmost the operator's resource and ingenuity. The instruments selected must include not only those required for the operation itself, but for all complications which may possibly arise. At the same time the simpler they are, cceteris paribus, the better. Preparation of the Animal. Great importance used formerly to be attached to the preparation of the animal, which was bled, and purged secundum artem. Such methods are now nearly obsolete, and the chief precaution required is to avoid casting an animal with a full stomach, overloaded bowel, or distended bladder, although the fear of rupturing the stomach, bowel, or bladder has been greatly exaggerated, as is proved by the small mortality in animals cast for urgent operations without reference to the state of the bowels, etc. It is, however, certainly advantageous to restrict the patient's diet before practising reduction of hernia, cryptorchid castration, spaying, and operations on the womb. The seat of operation should be thoroughly cleansed, the hair shaved off, and in the case of operations on the foot a local anti- septic bath should be given. Operations become necessary at all times of the day, but when a choice is available the best time is probably the morning, as any unfavourable sequelae, like secondary bleeding, are more easily discovered and dealt with then than in the late afternoon or evening. Recovery is often favoured by turning the animal to grass, for which reason spring is a very good time to choose when an option exists. The extremes of temperature occurring in winter and summer are disadvantageous. Great heat favours putrefactive processes in wounds, and flies, besides irritating the animals, often infect the parts. Place of Operation. When no special operating room is available, some open well-lighted spot, sheltered from wind and dust, should be chosen. The ground should be covered with clean straw to the 4 ASSIstanc IE AT OPERATIONS. depth of eighteen inches or two feet. Litter should certainly not lie used. For dogs an operating table will be found most convenient. It is seldom wise to operate in a loose-box. If the horse is lying and unable to rise it should be drawn into an open space. Assistants. In preparing for an operation sufficient reliable assistance must be provided. Each assistant should be carefully instructed beforehand in his duty, whether it be holding, casting, or fixing the animal. To command efficiently and preserve order the surgeon must thoroughly understand every detail himself, a knowledge which can only be acquired by actual manual performance. Students, therefore, should themselves have opportunities of casting horses, each taking command in turn, until all know their duties. In addition to the men required for holding, casting, and tying the horse, the operator requires an intelligent personal assistant. An expert is not always necessary ; a layman with some dexterity serves the purpose very well. This assistant should wash, shave, disinfect, and prepare the field of operation ; collect the needful instruments, hold retractors, sponge the wound, etc. ; but as he then comes in contact with the wound in nearly the same degree as the operator, the same precautions are incumbent on him as on the surgeon in relation to disinfecting hands, nails, etc. For extensive, complicated, and dangerous operations, however, such an assistant is inadequate. A qualified person is then almost indispensable, inasmuch as he should know immediately what to do in the event of dangerous complications arising ; what to compress, what to grasp, which instruments to hand, etc. There is often no time for the lengthened explanations a layman would probably require. Operations like the removal of tumours, etc., are seldom very urgent ; the surgeon has full time, therefore, to make all necessary preparations and to arrange for the help of a fellow -practitioner. Unfortunately, however, there appears to be an impression amongst many that the practitioner injures himself in the view of the owner of the patient when he suggests a consultation with, or the assistance of, a colleague. Others consider, on the contrary, that such a request is the best means of impressing on the owner the importance of the case, the difficulty of the operation, and the care which the practitioner is exercising ; and many of the younger generation of veterinary surgeons are beginning to adopt this view and to imitate their colleagues in human surgery. After-treatment. In many cases the after-treatment is even more important than the operation itself. The animal must be carefully watched to prevent it tearing off the dressing, rubbing RESTRAINT. or biting itself, lying clown, etc., while the temperature, condition of the wound, and its surroundings, etc., must be observed, so that any deviation from normal may be early remarked and precautions taken in time. II.— MEANS OF CONTROL. Operation, or even local examination, is often impossible without recourse to methods of restraint, of which an exceedingly numerous choice is available, depending on the species of animal and the operation to be performed. To begin with, the horse should be securely bridled or haltered and held by a reliable man, who will give his whole attention to the animal, and at once check any indication of vice by calling to the animal, or similar means. Vicious horses may often be quieted by the application of blinds. Before casting, a special well-fitting winker bridle, the lower part of which can easily be removed, should be applied. The winkers should be padded and pro- vided with straps, by which they can be brought together. By preventing it seeing, blinds often render the animal re- markably tractable, while they also protect the eyes when the animal falls, and whilst it remains on the ground. Some persons use a sort of leather cap or hood which is drawn over the animal's head. Some arrangement of the kind is indispensable when horses have to re cast. A substitute may be extemporised from a thick piece of cloth doubled several times, passed over the eyes, and fastened to the back of the bridle. Horses which bite may be muzzled. To divert the animal's attention from the local pain, twitches are often applied to the upper or lower lip, or to the ear. They produce most effect on well-bred horses. The simplest and most frequently used twitch is formed of a strong cord, threaded through the upper end of a stout rod. The end of the rod furthest from the loop is provided with a cord, by which the twitch, when applied, Fig. 1.— " The blinds; BLINDS AND TWITCHES. may be attached to the cheek-strap of the bridle. This obviates the necessity for a man holding it. The rod must never be fixed on that side of the face on which the animal will fall when cast, and Fig. 2. Operating cap or hood. Fig. 3. The twitch. Fig. 4—" The bulldogs. on which it may then continue to lie for some time. When dealing with very troublesome horses, the twitch stick may preferably be much longer, say six feet, and of proportionate thickness. It is then held by a man, who thus gains a considerable leverage over the horse, and is better able to control it. Neither the iron " bulldogs " (Fig. 4) nor the loop twitch (Fig. 6) is to be recommended. The loop twitch not infrequently lacerates the angles of the mouth, and it may induce partial sloughing of the cheeks. A very much better twitch is formed by passing the loop under the horse's upper lip, so that it lies above the upper incisors. This controls the animal almost as effectually, and is not likely to produce a blemish. The leg twitch is shown in Fig. 5. A stout piece of rope, about twenty inches long, is formed into a loop, through the open ends of which a wooden rod is thrust. This is applied to the hind limb, about four to six inches above the hock, and is tightened by twisting the rod. It being impossible to apply the ordinary cord twitch to the ox, Fig. 5.— The leg-twitch RESTRAINT. 7 a kind of forceps is used, which grasps the lower section of the nasal septum. The bull-holder (Fig. 8) is provided with loops at the free ends of the handles, by means of which it can be secured to the animal's horns. In the bull-holder shown in Fig. 9 pressure is applied by means of a screw. Nose-rings may here be mentioned; the most convenient are those which can be inserted without the assistance of an instrument. Hauptner's pattern (Fig. 10) is very practical. It consists of two semicircular pieces connected by a hinge ; one end is pointed and cutting, for the purpose of transfixing the nasal septum ; this fits into a corresponding depression in the other end, and is provided Fig. 15. — The loop twitch. Fig. 7. — The loop-twitch tightened by inserting a wooden rod. with a notch to receive the spring catch shown in the figure. Figs. 11 and 12 represent leaders for animals in which these rings have been inserted. To means of restraint also belong gags — instruments for holding the jaws apart to allow of examining or operating within the cavity of the mouth or pharynx without danger of being bitten. Some are fixed, others movable, the latter allowing the mouth to be more or less opened as desired. One of the simplest forms of fixed gag consists of a heart-shaped piece of iron with two transverse branches fixed about four inches apart. It is thrust into the mouth horizontally until the upper cross-piece comes in contact with the upper molars, and then rotated so that the upper cross-piece remains in contact with the interdental space and the animal's chin lies in the lower rounded space. Movable gags are preferable. The principle is similar to that above described, but the distance apart of the two s BULL-HOLDERS AND LEADERS. transverse pieces may be altered by means of a screw. Brogniez's gag has a semicircular bar, which connects the horizontal branches Fig. 8.— Bull-holder. Fig. y.— Bull-huldoi resting in the interdental space of the upper and lower jaws respectively, and which may be moved to either side. This gag has the disadvantage of requiring to be very strongly, and, therefore, Fig/ 10.— Nose-ring for bull. Fig. 11. Fig. 12. Bull-leaders. heavily made, though it certainly leaves the mouth very clear for operation. Mackel's gag is lighter, and does not require to be fixed RESTRAINT. with the hand. The upper and lower horizontal branches are separated by the rotation of movable nuts screwing on the two Fig. 13. — Showing the application of nose-ring and bull-leader. vertical connecting rods. Fig. 14 is VarnelPs form. The transverse bars are covered with rubber. Until recently it was by far the most Fig. 15.— Bayei mouth-gag for horses and oxen. Fig. 14.— Vamell's mouth-gag. Fig. 1(3. — Bayer's mouth-gag for dogs. popular form in this country. Fig. 17 is a design of Hertwig and Fuchs, so modified by Joger as to render it very portable. During prolonged operations the gums become severely bruised, even when the transverse bars of the gag are well covered with Ill HORSE AND DOG MOUTH-GAGS. rubber. To avoid this, Bayer, of Vienna, made the grinding surface of the molar teeth the point of support for a gag. This gag, shown in Fig. 15, will be seen closely to resemble that used for many years in operations on the mouth in man. It consists of an upper and lower portion, each provided with Fig. 17.— Joger's mouth-gag for horses. This apparatus can be dismounted and packed in a very small space. Fig. 18. — Woolf's mouth-gag — new form. guides for retaining the instrument in position on the respective rows of molars. The two portions are inclined towards each other at an angle of about 15 degrees. The back carries a handle for inserting the gag in place. The surfaces of the two plates being Fig. 19.— Woolf's mouth-gag— old form. roughened, after the manner of a rasp, assist in holding the instru- ment firmly when pushed between the upper and lower molars. In ase the animal's tongue is grasped with one hand and withdrawn, the instrument held firmly in the other hand is then introduced into RESTRAINT. II the mouth and pushed between the upper and lower rows of molars as far as it will go. The instrument should be steadied in position with one hand, whilst with the other the examination is made. As the operator himself controls the gag, he has ample warning to with- draw his hand in case of danger. Haussmann's mouth-gag for horses (Figs. 20—22) is probably the best and most convenient. Whether Fig. 20. — Haussmann's mouth-gag (open). If Fig., 21.— Rubber-covered plates for operations on incisor teeth. Fig. 22. — Haussmann's mouth-gag (closed). it was first invented by Haussmann or by an unknown American is open to question. In Germany it is known as Haussmann's ; in England as the American mouth-gag. It possesses the important advantage of pressing only on the incisor teeth, and therefore is not liable to injure the mouth, however long its application ; it leaves the cavity of the mouth entirely clear, a great point when operating on teeth ; it is relaxed in a moment, and as readily extended. It can be dismounted and packed small and flat for L2 HORSE AND DOC! MOUTH-GAGS. travelling, and being nickel-plated and of rounded form, the parts are easily disinfected. To permit of operations on incisor teeth two rubber-covered plates are supplied. which fit across the interdental space and replace the ordinary teeth plates (Fig. 21). The gag shown in Fig. 16 is for small dogs. That designed l>\ Woolf is useful both for large and small dogs. Fig. 19 shows the older, Fig. 18 the newer improved apparatus. Fig. 23 represents the very simple and effective mouth-gag for dogs and cats introduced by Mr. Gray, M.R.C.V.S- It is very simple and cheap, is readily adjustable for large or small animals, and leaves the mouth unobstructed for operation, etc. operating on dogs precautions arc required to prevent the FlG. 23. — Mr. ({ray's inoutl gag for dogs. In ^utefz Fig. 24. — Pulling up and fixing a fore-fool for operation. JSP 1 « <^„<* Fig. 25. — Tying up the fore-leg. patient biting. The best and easiest method consists simply in securing the mouth with tape. A loop of broad unbleached linen RESTRAINT— LIFTING A FOOT. 1.-5 tape having been slipped over the animal's nose and lower jaw, and drawn tight, the end proceeding from the right side is carried towards the left ear, that from the left side towards the right ear, and the two fastened firmly behind the head. In some operations on horses it is sufficient if the ears are grasped by a couple of powerful assistants and the head drawn forcibly downwards. This does not completely insure the operator's safety, but it checks attempts at rearing and striking with the front feet. This method of drawing down the head is certainly better than Fig. 26. — Fastening the fore and hind pasterns together as a means of restraint. fastening the animal to a fixed object, though in cattle the best available means often is to fix a rope around the horns and attach it to a strong ring or post. Another means of restraint is to lift a fore or hind foot, preferably on the side on which the operator stands ; care must be taken, however, not to raise the limb so high as to give pain and cause the animal to rear. A fore-foot may also be raised and kept in position by passing a cord around the pastern and over the withers, in which position it is held by an assistant. This plan is preferable to that next - shown, viz., of fixing the pastern to the forearm by means of a rope or strap. In this case a small bundle of straw is often thrust into the 14 LIFTING FORE AND HIND-LIMBS. flexure of the knee to prevent the cord slipping off. As, however, the horse is apt to lose its balance, a serious fall sometimes results. To prevent striking out with the fore-feet a foot may be lifted or both legs fastened together above the knees. Another plan is to pass a cord or strap several times around the forearms and fasten it to the surcingle. Some operators fasten the fore-limb to the hind-limb of the same side by a cord passed round the pasterns (Fig. 26). This prevents the horse striking out . but may cause a severe fall should it struggle. There are several methods of holding up a hind-foot. A loop of cord may be passed round the neck and one of the free ends carried along the back as far as the root of the tail, around which a turn is taken ; the rope is then passed once around the pastern of the hind-foot to be held up. The horse is thus forced to bear a great part of any strain he may put on the limb. This is a simpler but not a better method Fi<;.27. -Pulling up and fixing a hind- foot for operation. Fig. 28.— The Hippo-lasso. than that of Hann, who carries a cord from a ring fixed to the top of the surcingle, first over the back and croup, then through a THE HIPPO-LASSO. 15 crupper and through the ring of a hobble attached to the pastern, returning once more through the crupper. By drawing on the free FlG. 29.— The Hippo-lasso applied. Fig. 30. — The Hippo-lasso in operation. The horse is about to lie down. end of the cord the foot is raised and can easily be held in position. In other cases the tail itself may be utilised, the cord being first fixed THE HIPl'O-I.ASSO, ETC. Pig. 31.— Method of securing the hind legs to prevent kicking during operation Fig. 32.— Fastening a bullock's bind legs preparatory to operation. FlG. 33. — Fastening one hind leg for operation or shoeing. RESTRAINT. IT to it by a l ' double sheet bend " (i.e., a special kind of knot which will not slip), and then passed through the ring of a hobble, when by drawing on the rope the foot will be raised. For dangerous horses Fig. 34.— Fastening i\\ for operation. a very useful apparatus is the hippo-lasso. It may either prepare the way for using hobbles, or may even supersede them. It consists The side-stick. of a front and hind portion hung by broad straps which pass across the back just behind the forearm and in front of the stifle-joint respectively, and held together by two other straps fastened to the 18 SECURING OXEN. THE CRADLE, ETC. front and running through rings in the back portion. By pulling on these straps the animal's fore and hind limbs are drawn together, and it is effectually prevented from kicking either with the fore or hind limbs. Many horses when thus secured lie down without struggling. To secure the hind limbs hobbles are applied to the pasterns, from each of which a broad band of webbing is carried towards the centre of the chest from within outwards around the forearm under the preceding portion and vertically upwards over the withers. The two pieces of webbing may then be tied together. Hess describes many very useful ways of fixing oxen, of which the best are shown in the accompanying illustrations (Figs. 32, 33, and 34). Fig. 36.— The " cradle " or " beads." Among other means of restraint must be numbered the side- stick (Fig. 35), a cylindrical well-rounded stick of elm or other tough wood fixed at one end to the head-collar and at the other to the surcingle, thus limiting the movement of the head and neck. A somewhat similar result is obtained by the use of the " cradle " (Fig. 36). " The stocks," or " trevis," is so well known as scarcely to require description here. It was used in classic Greece. It renders good service in certain operations, but is too clumsy, too little adaptable, and too large for many purposes. Farriers still use it for shoeing, and country practitioners for operations on oxen and on heavy horses. AH vaccine institutes, and most foreign veterinary schools and OPERATING TABLES. 19 veterinary hospitals now contain some form of table for controlling horses during operation. The first apparatus of this kind of any practical value was Daviau's. It consisted of a large oak table about 8x6 feet, the upper part of the front padded with horse-hair and covered with Fig. 37. — Daviau's operating table. Horse secured. stout leather, the lower portion and the ends perforated with holes for the passage of ropes, the whole pivoted on a horizontal axis, to which was attached a rackwork quadrant. At the back was a stout framework about 2 feet 6 inches in height, with four legs so arranged that the upright table could fold back upon it, when the whole had Fig. 38. — Daviau's table. Horse in position for operation. somewhat the appearance of an extremely massive and rather low kitchen table. In practice the horse, already provided with a powerful head-collar, was led up to the apparatus, and strong ropes attached to the head-collar were passed through holes in the table and secured at the back to belaying-pins. At the same time the C 2 20 OPERAT1NC tables. Pig. 39. —Operating table used by Mr. Dollar. The horse secured for operation. OPERATING TABLES. 21 broad horizontal strap (attached at each end to the table) was brought round the chest and flank, and fastened by drawing the buckles tight. The vertical straps were secured, the hobbles adjusted on the feet, and the ropes controlling them tightened and fastened to belaying-pins behind the table. Thus secured, the horse and table were turned through the arc of a circle by working the crank handle seen on the left side. For minor operations this table served a very useful purpose, but a patent defect was the inaccessibility of one side of the horse, and the need, when both sides had to be operated on, of releasing, turning round, end refastening the animal. The most practical apparatus hitherto introduced is probably that shown in Pigs. 39 and 40. It was originally invented about 1890 by M. Vinsot, a former student of Alfort, but at that time was not centrally pivoted and possessed few r advantages over Daviau's table. Since then, however, Monsieur Vinsot has greatly improved it and the apparatus is now in use in all the chief foreign veterinary schools and hospitals. The main portion of the apparatus is seen roughly to consist of two approximately rectangular end pieces, connected at the top by a strong steel girder, and at the bottom by a strong iron rod of circular section. These rectangular frames are further connected at 2 feet 6 inches from the ground by two movable rods, adapted to swing open, and the whole framework is supported and pivoted on two powerful axes, placed as nearly as possible on a level with the general centre of gravity of the whole machine. A double cushion, intended to support the horse when lying, is capable of attachment to either of these side rods. The purpose of the various ratchet wheels and chains will be better understood by reference to the figure showing the horse secured in position for operation. His head, secured by a strong head-collar and side-ropes, rests within the padded upper portions of the front frame. Under his body passes a strong " bed-piece " reinforced with leather straps, the extremities of which carry iron eyes for the reception of a chain, by tightening which he is lifted almost off his feet just before turning over. In front this " bed-piece " is secured in position by a strap passing round the chest, and behind by a crupper attached to the back chain. The chain is wound on a spindle, turned, through the medium of gearing, by the crank handle shown. The horse's feet are fixed by hobbles to a strong chain running along the whole length of the bottom of the apparatus, and tightened by turning the lower of the two crank handles seen to the left. 22 OPERATING TABLES. m i OPERATING TABLES. 23 To support the revolving part, which weighs 7 cwt. and is capable of accommodating horses of any size, two strong iron standards 4 feet 6 inches high, and provided with stays of 2-inch iron, are sunk in the ground, where they are surrounded by masses of concrete weighing five tons. This provides a practically immovable base, on which any accidental shocks can have no effect. Each standard carries at its upper part a carefully turned bearing to 1 receive the axes of the revolving part. The forward end-piece is padded inside to prevent the horse accidentally injuring his head, and is perforated throughout its upper part with one-inch holes to permit the head-collar ropes being passed through and fastened to spring belaying -pins seen projecting in front. The rods suspended from either end of the upper girder are telescopic, and automatically stop the machine when tilted at what- ever point desired by the operator. Lastly, the revolving portion of the apparatus in which the animal is fixed is secured against premature movement by four " safety chocks " or catches secured to the standard, and locking with the end frames. The lever arm shown at the back and on the left side of Fig. 39 can be affixed to either end of the machine, and gives the operator the necessary purchase for moving the animal when in position. The disposition of weight has been so carefully planned that when ready for rotation horse and machine form a mass whose common centre of gravity is within an inch or two of the horizontal axis around which the whole moves. Very little exertion is therefore required in handling even a heavy horse, and no undue strain is thrown on the machine, whatever the point at which it may be brought to rest. In use, the horse is first provided with a strong head collar carrying two stout lines, and the " bed-piece " is strapped tightly round his body like a horse-rug. One of the side rods is swung open, giving admission to the machine, and the horse is walked forward until his head comes within the front frame. At the same moment the assistant follows up with the side bar, and as the horse enters, drops the bar in place, where it locks of itself. The groom passes the head collar lines through holes in the front frame, and drawing them tight winds them in a figure of 8 round the spring belay ing-pins, while the " bed-piece " is hooked on to the hanging " compensation bar." If a comparatively simple operation is to be performed nothing further is needed. A hind-foot may be drawn up and fixed for examination or dressing, and the horse be set at liberty again in less than a couple of minutes. 24 METHODS <»K CASTING ANIMALS. If, however, any serious operation is required four hobbles are affixed to the feet, the winch handles are turned (both together) until the horse's feet begin to leave the ground, when the safety chocks are cast off, permitting the apparatus to revolve, and depositing the horse without shock or pain in a horizontal position. The animal may be placed at any degree of inclination to the horizontal, and its position on the table is extremely safe. Broken back has never occurred within the writer's experience. Methods of Casting. A permanent bed is usually prepared with six to eight inches of dry spent tan bark covered with a thick layer of short cut straw. Many practitioners still prefer the straw bed to mattresses, because it is softer and because it can be removed, and fresh straw supplied after each operation, whilst the mattress must be thoroughly cleansed and disinfected. It has also the advantage of being cheap, as clean straw is readily obtainable and may afterwards be used for bedding, whilst it is a difficult matter for veterinary surgeons in country practice to convey a mattress from place to place. Nevertheless, straw makes a very bad bed for aseptic operations, and wherever possible it should be replaced by a mattress covered with tarpaulin, or by a proper operating table, though some of the disadvantages of the straw bed may be over- come by covering it with a large tarpaulin before casting the horse. Even so high an authority, however, as Bayer adhered to the straw bed, preferring it partly, because he had to teach students who, in practice, would be unable to afford an operating table, and partly because of the success attained in his own clinique. In support of his recommendation he adduced a long series of cases in which the wounds left by the removal of shoulder abscesses, necrotic lateral cartilages, etc., healed by primary intention after suturing. To prevent internal injuries, like rupture of abdominal viscera. the animal should fast or only receive light food for several hours before operation, though, as already mentioned, this precaution is not absolutely indispensable. Should it be impracticable to perform the operation in the standing posture the operator should throw the horse on a sloping bed or bank of straw, so that the animal may fall as easily as possible. One of the simplest methods of casting is that shown in Fig. 41. It is especially useful for young animals or those difficult to approach, in which ordinary hobbles cannot be used. It is also useful where the hind legs have to be drawn downwards on either side of the body for operations in the dorsal position, inasmuch as the application and removal of hobbles are thereby rendered unnecessary. In case of need a cart rope may be RESTRAINT BY CASTING 25 used. A strong bridle or halter and a surcingle carrying a ring and rope having been applied, a man is placed at the horse's head, and another, who holds the surcingle rope, is given a position on the side towards which the animal is required to fall. If possible the fore-foot furthest from the bed is then lifted. On the end of the long rope is tied a fixed noose, which is placed round the animal's neck like a collar ; the free end is then passed around both hind legs, brought forward, again passed through the loop on the animal's shoulders, and given to the men charged with casting the animal. On the word being given, these men should rapidly draw the rope backwards towards the side to which the horse is intended to fall. w^gga*** - ; - wzz Fig. 41. — Casting with the cart rope. Attention is directed to the fact that both hind pasterns are embraced in the one loop of rope. The rope thus catches in the heels just below the fetlock and the animal is thrown on its haunches. At the same moment the man holding the cord attached to the surcingle pulls in a similar direction. The attendant in charge of the head assists the movement, and the horse falls to the ground. This method causes the least concussion, and can even be safely used for pregnant mares. The only objection is that if the ropes be new, or the first attempt fail, the animal's heels may be injured, but this can be avoided by previously applying bandages or using cotton ropes. Where many horses are cast by this method the loop of rope passed round the neck may advan- tageously be replaced by a strong leather strap provided with iron 26 CASTING WITH ROPES. eyelets, through which the rope is returned, these eyelets diminishing friction and permitting the rope to run more freely. A commoner method of procedure is to form in the centre of a long rope a fixed loop sufficiently large to pass round the animals neck and rest on its shoulders. The knot lies in front of the chest. and the tree ends of the rope are passed from within outwards round bbles. the hind legs above the hocks, and back again through the neck loop. They are then held on each side by one or two men. according to the animal's size and weight. When all is ready one of the fore- feet is lifted, the loops of rope are slipped from above the hocks downwards into the hollows of the heels, and the men pull steadily on the free ends of the rope, causing the animal to subside on its Fie. 43. — Cross-hobbles, or thigh and forearm straps hocks, whence it usually falls gently on to its quarters. It is best if one group of men pulls outwards at right angles to the shoulder and the other somewhat backwards. Immediately the animal is on the ground it is pushed on to its back, the ropes are pulled tight, drawing down the hind legs level with the abdomen, and secured to the pastern with one or two half-hitches. The fore legs are firmly METHODS OF CASTING HORSES. 27 grasped, brought alongside the hind, and secured to them by a couple of half -hitches passed round the pasterns. This method has the advantage of requiring no re-arrangement of the ropes to draw down the hind legs and so expose the field of operation for castration, though, as the hind limbs are at first comparatively free, the animal can plant them wide apart, and the force required for casting it is somewhat greater than in the method previously mentioned. It is usually employed when castrating colts. Some operators use a stout leather strap collar with iron eyes for the passage of the ropes, instead of merely passing them through the improvised rope loop. When the Fig. 44. — The hobbles applied. animal is very active, it is well to affix a roller or surcingle to which the collar or neck loop can be tied ; otherwise the latter may slip off. To work the above methods successfully requires thorough discipline of and co-operation between the various assistants. In- attention on the part of anyone may entail serious accident or failure of the whole operation. The method of casting, however, most fre- quently employed is that illustrated in Figs. 44 and 45, which show the application of leather hobbles. The hobble usually applied to the upper fore-limb is called the master-hobble, and carries a special key, by means of which the chain or rope is attached. Traction on the rope draws the feet together, the horse begins to lose its balance, and at the critical moment the rope attached to the surcingle is pulled, one or more assistants helping if necessary by pulling on 28 CASTING WITH HOBBLES. the tail. The hobble rope should be pulled in a backward direction, as this to some extent neutralises the strain on the assistants, and prevents the animal's legs being pulled directly from under it and so bringing it violently to the ground. The assistants should be well drilled beforehand, and the operation carried out as quietly as possible. In Fig. 45 the horse is provided with Bernadot and Butel's apparatus for preventing broken back. The difference between this and the Stuttgart method may be seen on reference to Fig. 46. The advantage of the Stuttgart arrangement is that the ropes Fig. 45. — The hobbles applied together with Bernadot and Butel's apparatus for the prevention of broken back. The strip of webbing passed round the off forearm is intended to afford a purchase when pulling the horse over in the act of casting. run more easily, as each only passes through one link ; and as the direction of pull is opposite for the two groups of men, there is no tendency to bring the horse down violently on its side. The horse having been brought to the ground is kept down by the man at the bridle firmly pressing on the head, and other persons sitting on the shoulder and haunch respectively. The four feet having been tightly drawn together are fixed by passing a key (Fig. 47) through a link of the chain. The spring key shown is perhaps less convenient than the D-shaped spring key, though there is no essential difference between the two. As a makeshift the chain CASTING HORSES. . 29 may be fixed by forming a slip-knot as close as possible to the hobbles and passing a bundle of straw through the loop. The person at the horse's head must take care that the animal does not succeed in bending its head towards its chest and arching its neck, because this attitude, which facilitates contraction of the great muscles of the back and quarters, is often responsible for fractures of the vertebrae. To retain the head extended Bernadot and Butel invented an apparatus consisting of a strong head-collar, from which powerful straps run backwards above the neck, and are attached on either side to a ring in the surcingle. The surcingle is prevented from slipping forward by the use of a crupper. The apparatus is applied Fig. 46.— Method of casting as adopted at the Stuttgart Veterinary School. loosely before casting, and the straps tightened after the animal is on the ground. The releasing of an animal depends on the method employed for casting. Most hobbles are arranged so that all four feet are immediately loosened by withdrawing the screw-key of the master hobble, but where no such arrangement exists the fore and hind feet of the lower side should first be set free, and then those of the upper side. The assistants sitting on the shoulder and haunch should not move until the man in charge of the bridle is quite prepared for the animal's rising, and the word of command has been given. Should the fore-quarters be on a lower level than the hind, or the back lower than the feet, the horse may have difficulty in rising. In such case the fore-feet must be drawn out in front of 30 SECURING AND RELEASING LIMBS. the horse, and the animal assisted by men placed at its quarter, shoulder, and tail. The animal having been cast, it may become necessary to release and again secure a limb, according to the operation to be performed. For this purpose the best material is webbing ; cords are apt to cut. The webbing having been doubled, a running loop is formed in it and slipped over the horse's fetlock ; the two ends of webbing are then passed in opposite directions and held fast by assistants. The men sitting on the shoulder and haunch can also check the animal's movements by utilising their weight and by grasping the limbs with their hands. A better method, however, is to pass a loop of webbing around the two forearms or cannon bones. Movement in the fore and hind limbs which are for the moment uppermost, can also be Fig. 47. — The hobble- Fig. 48. — Bernadot and Butel's apparatus for the ehain key. prevention of broken back. checked by passing a large strap or piece of webbing over the hock- joint and then around the forearm, or by the application of the cross-hobbles shown in Fig. 43. For operations on the fore-limb, like extirpation of the lateral cartilage, neurectomy, etc., Moller's method of fixing the limb to a long plank is very useful. The plank should be well padded, and provided with a long curved iron handle. It is less useful for hind limbs, inasmuch as the limb can only be fixed at two points, viz. at the fetlock and above or below the hock. To draw a hind-foot closer to a fore-foot, as in preparing for castration in the side position, a running loop is formed at the end of a piece of webbing and slipped over the fetlock of the hind-foot ; the webbing is then carried over the withers, beneath the neck, over the front of the chest, around the forearm, and thence backwards, passing from below upwards around the Achilles tendon and once SECURING LIMBS AFTER CASTING HORSES. 31 again forwards. By pulling on the free end an assistant can then bring the limb into the position shown in Figs. 51, 52. Another Fig. 49.— Horse cast and secured. The near forearm and near thigh are fastened together by broad strips of webbing (the cross-hobbles may be used instead), and the off fore-leg is fastened to the plank ready for operation on the foot. (Moller's method.) Fig. 50. — This figure shows method of securing a hind limb to the plank for operation. Compare with foregoing figure. way of attaining the same object (the Berlin method) is shown in Fig. 53. 32 SECURING AND RELEASING LIMBS. The method of fixing the upper hind to the upper fore-limb is shown in Fig. 54 ; that of fixing the lower hind to the upper fore in Fig. 55. For operations in the dorsal position the fore and hind limbs of each side must first be firmly fixed together. Either rope or webbing Fig. 51. — The horse cast and tied. The off hind leg being drawn forward ready for castration in the side position. can be used, the fastening being accomplished by means of a running noose attached to the fetlock of the hind-foot, and by applying one or two half-hitches to that of the fore-foot, drawing the rope tightly after each half hitch is in position. When the horse is rolled on to its back, care must be taken that the neck and head are kept straight Fig. 52. — The horse secured ready for castration in the side position. and the head is not allowed to be bent towards the chest. A piece of webbing can then be fastened to one of the hind limbs just above the fetlock, passed under the animal's back, and then from within outwards over the fetlock of the opposite side. By drawing this tight the hind legs are pressed down close to the sides and secured. In Vienna a special piece of apparatus is used for this purpose. The SECURING HORSES FOR OPERATION. 33 Fig. 53.— Another method of preparing the horse for castration or similar operation in the side position. Fig. 54. — Fastening a hind to a fore-limb preparatory to neurectomy, firing, etc. 34 RUSSl \N MKTHol.) OF CASTING. method is as follows :— One or two assistants grasp the horse's tail and lift the hind quarters far enough from the ground to allow a leather hand, about eight to ten inches wide, to he slipped under. The ends of the band cany broad iron rings. Through these and around the cannon bones of the hind limbs broad pieces of webbing arc passed, securing the hind limbs in place. The cannon bones must be pressed downwards into a horizontal position, whilst the parts are being fixed (Fig. 57). (Note. — In this figure the assistants on the left side of the animal are not represented, and the horse is purposely shown lying a little obliquely, in order that the mode of fixation may lie clearer.) The operation finished, the broad leather Fig. 55. — Fastening the lower hind to the upper fore-limb preparatory to neurectomy, firing, etc. This figure also shows the " leg twitch " applied. strap passed beneath the animal is first removed : the horse is then laid on his side, the limbs are released, "the upper being last of all freed from hobbles. Fig. 58 shows another method of fixing a horse for operation as employed in the Berlin veterinary school. The Russian method of casting (Figs. 59-61) permits of a man throwing a horse single-handed. In books the position of the operator's hands is usually incorrect. With small horses the method succeeds very well, though requiring sonic courage. The operator stands close to that side of the horse on which it is intended to fall, and at the first trial this seems dangerous. Bayer, in referring to the operation, states that on one occasion he actually fell under the SECURING HORSE IN DORSAL POSITION. 35 horse. He had attempted to cast a rather large horse, and had nearly succeeded ; the animal, however, tried to regain its equilibrium by a slight spring, and trod on Bayer's foot, preventing his getting clear. Fig. 56.— The horse cast. Mode of fixing the fore and hind limbs together when preparing for castration in the dorsal position. A long rope carrying a ring at one end is used. Supposing a horse is intended to fall on its left side, a loop is formed in the rope and passed around the neck, the ring lying near the right elbow. The free end of the rope is then passed around the left hind-foot, Fig. 57.- -Preparing for castration in the dorsal position, applied. (Vienna method). The back strap again through the ring, and is held in the operator's right hand. The operator stands on the horse's left side looking forwards, his right elbow supported on the horse's loins, and the bridle reins grasped in the left hand. By lifting the left hind-foot under the 36 CASTING THE HORSE SINULE-HANDED. belly and somewhat towards (lie right side, drawing the bead to the right by means of the bit, and simultaneously pressing with the elbow on the loins, the horse is caused first to recoil on its haunches, and then to lie down on its left side. The operator has only to hold the cord and bridle tight to prevent the animal rising. Cattle can be cast like horses with ordinary hobbles, the straps being placed above the fetlocks, or by the method shown in Figs. 62 and 63. A rope having been fastened to the horns, is passed around the neck, chest, and abdomen as shown. The animal is held by an ox-lead, and two men pull on the end of the rope, when Fir,. 58. — Berlin method of fixing the horse in dorsal position for operation. the animal usually lies down on its side without struggling and with its feet stretched out. For castration the sheep is placed on its hind quarters in a sitting position, the abdomen being turned towards the operator. An assistant grasps the body between his legs and holds a limb with each hand. For carriage the fore and hind legs of each side are first tied together, the two sides being afterwards connected by a few turns of the rope. The pig is best seized just above the hock, and can then be cast by .in assistant who grasps the ears. In the large stocky aids, however, men become very expert in casting the pig single-handed, by slipping a short staff between the hind legs as the animal runs. To examine A RUSSIAN METHOD OF CASTING HORSES. 37 the mouth, a short stick is thrust between the jaws at the moment when the animal squeals, and can then be used as a lever to keep them open. A kind of twitch applied to the jaws is also used. 59. — The Russian method of casting, single-handed ; first position. 60. — The Russian method of casting, single-handed; second position. Fig. 61. -The Russian method of casting ; the horse down. Another method is as follows : — Two men grasp the pig by the ears ; when the animal cries, a slip-knot, formed on the end of a stout cord, is passed into the mouth and fastened to the upper jaw as near as 38 SECURING SMALL ANIMALS. possible to the commissure, behind the tusks. The cord is then fastened to any high point or to a ring, and the head drawn into a position of forced extension. The animal cannot possibly escape. The dog is either muzzled or the jaws fastened together by a piece of tape passed around them and tied behind the ears. It is then -Casting an ox ; first position easily handled and secured on the operating table. Several operating tables have been invented for dogs. In Vienna the table is a shallow glass trough about 3 feet 6 inches long and 15 inches across, with an aperture for drainage, and suitable connections at the lowest point. This is surrounded by a detachable metal frame, the lower surface of which carries a series of hooks at one-inch intervals for fastening the cords by which the animal is secured. In the very excellent clinique for small animals at Berlin, the table is of similar Fig. 63. — Casting an ox ; second position. form, but is constructed throughout of metal. Both tables, in fact, are close imitations of those used in human surgery. In this country, Hobday has suggested a cheap and useful table of wood, the upper surface perfectly fiat and displaying numerous slots for receiving the small keys by which the hobbles are secured SECURING SMALL ANIMALS. 39 to the table. This table, now made of metal, can be readily cleansed and rendered aseptic. Another excellent table, of wood, designed by Claude Bernard, consists of four parallel leaves connected by hinges. The two outer leaves may be inclined at any angle towards one another, forming a trough to receive the animal's body. Owing to its great simplicity and absence of depressions likely to retain dirt, etc., this table is cheap, and responds to most of the require- ments of veterinary surgery, while it is readily adaptable to animals of varying size, and when folded is quite portable. A special instrument is used in France for securing dogs suspected Fig. 64. — Operating table for the dog. (Claude Bernard's design.) of rabies. It has a long handle, and carries at the end a spring collar which, when pressed on the dog's neck, opens and holds him securely. For castration and other operations on the cat, the skin at the back of the neck is grasped with one hand, that over the lumbar region with the other, and the subject firmly pressed down on a table. Another method is for the assistant to grasp the hind limbs on either side between the second and third fingers, the fore-limbs between the index and second fingers, and the skin on either side of the head with the index finger and thumb. Thus held the animal is quite powerless. Troublesome patients may be wrapped in a thick cloth to prevent scratching and biting. It is sometimes recom- mended to thrust the animal into a narrow sack or into a boot. 40 SECURING SMALL ANIMALS. These methods, of course, are primitive and only suitable for trifling operations. For more complicated operations one or another of the above-mentioned tables may be used. Other methods of casting and restraining horses, cattle, pigs, and dogs, will be found fully described and illustrated in Restraint of Domestic Animals, by Dr. White, Nashville, Tenn., U.S.A. Complications. Application of the above-described methods of restraint are not infrequently followed by injuries or complications. The animal begins to resist immediately the hobbles are applied. A horse often struggles, kicks, or moves away on finding the free use of its limbs checked, and may fall awkwardly, breaking the jaw, neck, shoulder, or a limb bone, according to the incidence of the shock. Fracture of the spine, pelvis, or ribs is not infrequent when horses are cast suddenly and violently. Even when secured, the muscular efforts consequent on struggling may cause fractures of vertebrae, of the pelvis, of the femur, os calcis, etc., rupture of abdominal viscera, of large vessels, important muscles, or of tendons, not to mention the skin wounds and contusions which frequently occur. Pressure on nerves such as the facial or radial, due to lying long in one position, may be followed by cramp or paralysis. Fig. 64a. — All-metal operating table tor small animals. ANESTHESIA. 41 III. ANAESTHESIA. Anesthesia may be divided according to its nature and extent into general and local. We shall consider these in order. The first operation under ether was performed on the 14th October, 1846, by Warren, in the Faculty of Medicine at Boston. Boots and Lister first employed ether in England. During 1847 several veterinary surgeons published experiments showing the advantages of its use in operations on the horse. Notwithstanding certain drawbacks ether was at first exclusively used, but on the 10th November, 1847, Simpson drew attention to the anaesthetic qualities of chloroform, which he declared superior to its predecessor. Chloroform soon displaced ether, maintaining its supremacy in man until a relatively recent date. In animals, save perhaps the dog and cat, it is still the most popular anaesthetic. Other substances have since been introduced. The first departure was probably the mixture of ether and chloroform, with or without alcohol. The rectal administration of ether was then suggested, followed by the use of morphine, the intra-venous, intra-rectal, or intra-peritoneal injection of chloral, the inhalation of chloroform in conjunction with subcutaneous injections of morphine and atropine, and the administration of paraldehyde, urethane, and methylene. When, as in oxen, the flesh would be used for human food in case of the operation failing, large doses of alcohol are often given. In general anaesthesia the patient is thrown into a more or less profound artificial sleep. It is not always necessary, however, to act on the entire individual. Sometimes the operation only affects a very limited area, and local anaesthesia suffices. Local anaesthesia may be produced by the application of ice or freezing mixtures, by the spraying of certain liquids, like ether or ethyl chloride, or by the subcutaneous injection of a solution of cocaine, eucaine, stovaine, or novocaine. Anaesthetics are quite as useful in animals as in man ; and few important operations are performed on veterinary patients without anaesthesia, either local or general. For most minor operations, the means of control at our disposal are sufficient without general anaesthetics, but certain operations cannot be well performed without them. In reduction of hernia?, delivery in cases of dystokia, in laparotomy, and all cases where one works in dangerous proximity to important organs, the animal's struggles render general anaesthesia almost indispensable. It is also necessary for delicate operations on or 42 GENERAL ANESTHESIA. in the vicinity of the eye, and for all serious operations on horses, whose struggles are particularly violent. Moller recommends anaesthesia in castrating horses with very powerful dorsal muscles. Tn ruminants anaesthesia is seldom resorted to save in difficult parturition. In carnivora, and especially in the dog, its principal indications are in laparotomy, difficult parturition, amputations, and certain opera- tions on the head. Anaesthesia is contra-indicated (1) in diseases of the heart (lesions of the valves or myocardium, dilatation, and hypertrophy) ; (2) diseases of the respiratory tract (emphysema, pneumonia, and chronic pleurisy). Ether is the best anaesthetic for subjects with emphysema and dilatation of the right heart, chloroform for those with affections of the left heart, chloral when the pulse is intermittent (Arloing). Death may be caused by pushing administration too rapidly ; in certain rare cases it may also result from accidents like vomiting, the vomited material passing into the trachea and lungs, and producing mechanical pneumonia. Such a termination is much to be feared in man unless the patient be properly prepared, but it very seldom occurs in the horse. If in operations on the face, such as trepanation of the facial sinuses or nasal cavities, or extraction of molar teeth, an anaesthetic be employed, the head should be placed in a depending position, so as to favour escape of blood, which might otherwise enter the respiratory tract and produce suffocation. GENEEAL ANAESTHESIA. Narcosis being the result of a special action exerted directly on nerve-centres by the anaesthetic agent, the first necessity is to insure a sufficient quantity of the anaesthetic arriving at those centres. While fixed anaesthetics can be administered by various channels, such as the veins, mucous and serous surfaces, the subcutaneous tissue, etc., volatile anaesthetics must penetrate by the respiratory mucous membrane. Injected into the tissues or veins, fixed anaes- thetics traverse the pulmonary capillaries wit In ml sensible change, and act promptly on the nerve-centres ; volatile anaesthetics, similarly administered, escape in large measure through the walls of the pulmonary vessels, are expired, and fail to reach their destination in sufficient quantity to produce much effect. On the other hand, volatile substances, introduced in a state of vapour into the respiratory tract, are freely absorbed by the blood circulating ANESTHESIA. 43 in the lungs, which blood, passing thence to the left heart and general arterial system, rapidly produces anaesthesia. Anaesthetics administered by the respiratory tract produce a series of phenomena in the following order : — -(1) period of excitation ; (2) period of anaesthesia or surgical period ; (3) period of collapse or intoxication. The period of excitation, due firstly to the action of anaesthetic vapours on the nerve terminations in the mucous membrane of the upper respiratory tract and paralysis of the cerebral inhibitory centres, and afterwards to the action of these vapours on the great nerve- centres themselves, is characterised by perverted sensation, excite- ment, and hyperaesthesia of sense organs. Violent struggling occurs, respiration and circulation become accelerated, the mucous membranes injected, and the pupil dilated ; the heart's action, however, soon slows, respiration becomes easier, more regular, and more extensive, the pupil contracts, excitement diminishes, and sleep commences. During this period anaesthetics may, in animals predisposed to such complications, produce respiratory or cardiac syncope or asphyxia from spasm of the glottis. The period of anaesthesia is characterised by suspension of activity in the nerve-centres, i.e. the cerebral lobes, medulla oblongata, and mesocephalon. The animal is plunged into artificial sleep. The excito-motor centres are paralysed, the muscles relaxed, the limbs when raised fall inertly. Respiration is slow, the movements of the chest wall are diminished, but those of the flank more marked than ordinary. The heart is accelerated, on account of paralysis of the moderator centre, but the pulse remains regular and full up to the moment when intoxication occurs. Vision is no longer co- ordinated, while the pupils remain contracted and immobile. As sensation is lost in the various regions reflexes cease. Sensation does not disappear simultaneously in all tissues and all regions, being last retained by organs under spinal control. The limbs and trunk are first affected, then the organs of sense and those supplied by branches of bulbar origin, finally those supplied by the sympathetic system. The nasal, buccal, auricular, and genital mucous membranes exhibit reflexes long after other parts have become insensitive. Even when anaesthesia appears complete, struggling often results immediately the knife touches the diseased region. This is due to certain diseased tissues retaining a morbid sensibility even after neighbouring healthy tissues have entirely lost sensation. Inflamed parts especially retain their sensibility long after healthy tissues. Once established, anaesthesia can be maintained by very 44 ANAESTHESIA IN THE HORSE. small closes of the agent employed ; larger amounts are dangerous, as being liable to induce the third stage of anaesthesia, viz. collapse or intoxication. This is characterised by progressive retardation of respiration and circulation, and by sudden dilatation of the pupil. Respiratory movements become superficial and cease for compara- tively long periods ; the heart's action diminishes, the pulse is small, soft, and irregular. Finally the medulla becomes intoxicated, respiration is arrested, the heart ceases to beat, and death occurs by respiratory syncope. The phenomena of anaesthesia vary according to whether ether, chloroform, or another anaesthetic is employed. With ether the period of excitement is longer and more pronounced than with chloroform. With certain fixed anaesthetics the phase of excitement is suppressed or little marked. Although the exact action of chloral is still open to discussion, it is known to produce immediate and profound anaesthesia without preliminary disturbance when adminis- tered intra-venously. On the other hand, salts of morphine some- times produce lively excitement prolonged for some hours. The difference, however, interests physiologists more than practitioners. The chief point for the latter is the degree of toxicity of these agents. i.e. the danger attending their use. No general anaesthetic is without danger, and even in veterinary surgery, where the employment of anaesthesia is limited, every practitioner has probably had a fatal ANAESTHESIA IN THE HORSE. Chloroform probably produces the most rapid and complete anaesthesia in the horse. It is not so dangerous for solipeds as lias been suggested. The writer, whose experience extends to nearly a thousand cases, has only seen two fatal results, which occurred after deep surgical anaesthesia had been maintained, in one case for over two hours, and in the other over three. Needless to say, recovery of consciousness is slow after prolonged operations, and the animals may not rise for half an hour to an hour after their termina- tion, but given reasonable care in administration chloroform fulfils all requirements. In company with Dr. Clarke, the writer attempted on several occasions to kill animals by the administration of air saturated at ordinary temperature with chloroform vapour, hut the experiments all proved the extreme difficulty of the attempt. Where, however, the animal is partially asphyxiated, as in using several of the common veterinary inhalers, death can be produced in eight to ten ANAESTHESIA. 45 minutes. By using a special apparatus, by means of which abso- lutely pure chloroform vapour, without admixture of air, was administered, death was produced in one and a half minutes. The heart's action continued for several minutes after respiratory arrest. Moller, who employs chloroform exclusively, has administered it to many hundreds of horses without a single accident. As a basis for investigation, Moller noted in each of his cases the time required to produce surgical anaesthesia, the amount of chloroform used, the breed, age, sex, and weight of the animal. The following is a resume of the more important results. In a series of 126 cases (31 stallions, 38 mares, and 57 geldings) anaesthetised with chloroform, the corneal reflex was abolished in an average period of 20 minutes by the administration of an average quantity of 28 fluid drachms of chloroform ; the quantity per unit of body-weight was 1 : 4000 ; anaesthesia usually lasted about 20 minutes. Whilst in one to two years old animals 4 to 5 drachms of chloroform usually produced anaesthesia in 7 to 8 minutes, the shortest time observed in full-grown horses was in one case 8 minutes, in one case 9 minutes, and in two cases 10 minutes. Twelve of the above 126 horses required 30 minutes, and four from 30 to 40 minutes. In stallions the average period was 18, in mares 19, and in geldings 22 minutes. The stallions on an average consumed 30 drachms of chloroform ; 7 horses (3 stallions, 2 mares, and 2 geldings) took, however, less than 12| drachms ; on the other hand 18 (5 stallions, 4 mares, and 9 geldings) required 38 fluid drachms, or over. One gelding received 60 fluid drachms, and an English thoroughbred 62| fluid drachms. The average age of the stallions was 5, of the mares 9, and of the geldings 7 years. It is worth noting that the quantity of chloroform used depends partly on the method of administration. Apart from the quantity lost by leakage or evaporation, less is required when administration is slow than when it is rapid. The quantity used, therefore, often stands in inverse proportion to the pre-anaesthetic period. Breed seems to have little relation to the anaesthetic influence of chloroform ; it neither affects the quantity required nor the pre- anaesthetic interval to any appreciable extent. On the other hand, it was noted that geldings on an average required considerably more chloroform than stallions and mares. Twenty-eight horses received subcutaneous injections of lh grams morphine before administration of chloroform. In these cases the average quantity of chloroform used was 24 fluid drachms, and the time interval before complete anaesthesia 15J minutes. 46 ANAESTHESIA. Eight horses were given a mixture of equal parts chloroform and ether. The average quantity used was 54 fluid drachms, and the time interval 30 minutes. Needless to say the sample of chloroform used must be pure, and should contain no free chlorine, which produces excessive irritation. To prevent chloroform undergoing change by keeping, a little ether is added to it and the liquid placed in yellow bottles with ground stoppers and stored in a cool dark place. Another method consists in adding 1 part in 1000 of sulphur which has previously been washed with ammonia, and afterwards with water. Apparatus. Chloroform can be administered from a towel, sponge, tampon of tow, or a linen compress, but in England Cox's or Carlisle's muzzle is usually employed. Although the rapid method is con- sidered dangerous by some, it is that most commonly used. Abroad great precautions are taken. The chloroform is given from a compress, and by one nostril only, being added drop by drop at the rate of two or three drops per second. To avoid irritation, produced by the liquid coming in contact with the skin or mucous membrane, the nose may be smeared with vaseline. Being very volatile, chloroform can be given by a modification of Junker's apparatus. In its simplest form this consists of a tall glass cylinder, containing the ansesthetic, closed by a bung or large rubber cork pierced with two holes, giving passage to wide glass tubes. One tube passes to the bottom of the glass ; to this is affixed the bellows ; the other, which only just passes through the cork, is provided with a rubber tube which can be slipped into the animal's nostril. By working the bellows, air is forced through the liquid, becomes charged with the ansesthetic, and, passing into the nostrils, is inhaled. A large form of this apparatus, made in copper and worked by a foot bellows, was very successfully used by Dr. Clarke (who invented it) and myself during 1887-9 in operations for roaring. The glass bottle was replaced by a copper cylinder about fifteen inches in height and four in diameter, the glass tubes by large metal tubes about three quarters of an inch diameter. The long tube passed to the bottom of the copper cylinder and through a circular plate of perforated metal. The blast of air was thus broken up into innumerable small bubbles, which became thoroughly saturated with the ansesthetic vapour. As after prolonged use the apparatus grows extremely cold, and is apt to become clogged from the freezing of water vapour derived from the blast of air, it was found advan- tageous to place it in a bucket containing warm water. Later forms SURC41CAL ANAESTHESIA. 47 of Dr. Clarke's apparatus are surrounded with an outer metal receiver for containing hot water. A simple form of inhaler was suggested by the late J. Roalfe Cox, F.R.C.V.S. It consisted of a leather tube covered with stout canvas, which could be drawn together at either end by a strong drawstring. The tube was slipped over the animal's nostrils and into its mouth, the drawstring tightened and attached to the halter. A sponge saturated with the anaesthetic was then introduced, and the supply of air controlled by regulating the size of the external opening. The Carlisle inhaler is more complicated, but probably not more efficient. It envelops both the upper and lower jaws, thus differing from Cox's, and is provided with a metal sliding sponge-holder on which the chloroform is poured. As sent out it gravely impedes respiration, and for use the writer has modified it by removing the lower solid end, so that the only obstacle between the animal's nostrils and the outer air is the comparatively pervious layer of sponge for receiving the chloroform. Thus altered it uses rather more of the anesthetic, but is infinitely safer. Surgical Anaesthesia by Chloroform. Chloroform is usually ad- ministered as follows : — Food having, if possible, been withheld for six hours, the horse is cast, and girths or other impediments to free respiration loosened or removed. During inhalation, attention must be given to the breathing and the pulse. Both are at first accelerated, but later become regular. Unless when using one of the anaesthesia cum asphyxia muzzles, the excitation stage is seldom attended with danger, only lasts a minute or two, and is succeeded by the period of depression. The first stage of anaesthesia (excitation) is often accompanied by a peculiar rotary movement of the eye (nystagmus) ; in some animals the eyelids close, opening again when anaesthesia is complete. If, soon after the period of excitement has passed, respiration or circulation becomes impeded, or if respiration be laboured, very rapid, or interrupted, if the pulse be small, frequent, irregular, or intermittent, administration must be stopped. General muscular twitching may also occur, and calls for similar precaution. Rattling in the throat, a serious symptom in man, is of less importance in horses. In the event of its occurring, the tongue should be grasped and drawn forward. Even then the noise does not always cease, being probably due to vibration of the relaxed soft palate, which is set in motion by the 'stream of air passing through the mouth during respiration. The loss of sensibility, muscular weakness, character of the pulse 4 s GENERAL AN.ESTHESIA. and respiration, variation in the pupil, and the persistence or loss of the corneal reflex indicate the degree of anaesthesia. Complete anaesthesia is characterised by disappearance of the oculo-palpebral reflex and contraction of the pupil. At this stage should the conjunctiva or cornea be touched no movement of the eyelids follows, and touching the cornea has therefore become the usual test of anaesthesia. When the corneal reflex ceases inhalation may be stopped, to be resumed with its reappearance. The test is doubly valuable : it shows anaesthesia to be complete, whilst its disappearance is usually long antecedent to the period of intoxica- Fig. 65. — Cox's chloroform muzzle. Fig. 66. — Arnold's modified Carlisle chloroform muzzle. tion. Too much weight, however, cannot be attached to the advice " watch the breathing." The breathing, and not the pulse or any other sign, is the only safe guide in administering an anaesthetic. The abolition of the corneal reflex usually occurs long before respiration is endangered, so that it is a convenient guide ; but its occurrence is subject to irregularity, and it must never be relied on to the exclusion of the breathing. Variations in the pupil also afford valuable information. As anaesthesia becomes pronounced, the pupil, dilated dining Hie period of excitement, contracts. During anesthesia it remains contracted and immobile, dilating slowly as sensibility returns. Rapid dila- ASPHYXIA. 49 tation at an advanced stage of anaesthesia is a sign of bulbar intoxication and of imminent syncope. When the corneal reflex is lost and the pupil contracted, sensibility has disappeared, and muscular relaxation is complete. Provided respiration and circulation continue regular, anaesthesia can then be prolonged for periods of two or even three hours without danger by occasionally administering further small doses of chloroform. On completion of the operation the hobbles are removed ; but the horse is left undisturbed until it rises of itself, which will usually happen in a quarter to half an hour. Should the animal be forced to rise before consciousness has entirely returned, it walks unsteadily, " bores " forward like an animal with brain disease, and may fall. To support it an assistant may walk on each side, with a hand on the point of the hip, and one behind holding the tail. Administered with the foregoing precautions chloroform becomes a perfectly safe anaesthetic for the horse, and though individual animals show special susceptibility to its action, yet in general the danger is infinitely less than was formerly imagined. Fatal issues result either from asphyxia or syncope. Asphyxia usually occurs during the period of excitation, especially if some closed muzzle like the Carlisle muzzle or its modi- fications be used ; first breathing stops, and after a short interval the heart's action fails. Asphyxia may also happen towards the end of the anaesthetic period if administration has been pushed far and is suddenly checked. In such case the sides of the chest, face, or lips should be smartly struck with the hand or a wet towel to provoke reflexes and restore respiration. When arrest continues for an appreciable period (the writer has timed arrests of thirty to forty-five seconds), artificial respiration may be resorted to. A fairly heavy assistant stands between the animal's legs and presses with his entire weight on the animal's chest, rising again almost immediately. This is repeated at intervals of about four or five seconds. The shock should not be violent : but the man's whole weight should be employed, and special attention must be given to regularity in the process. In the horse it rarely happens that the tongue recedes and by covering the opening of the larynx causes asphyxia. Should any indication of this — like loud snoring, etc. — occur, the tongue should immediately be grasped and drawn forward. In cases of respiratory failure some French investigators have recommended the system practised in man for resuscitation . 50 ANESTHESIA IN THE STANDING POSITION. from drowning, viz.. repeated rhythmical traction on the tongue (lingual traction) at intervals of two to four seconds. The theory' is that the superior laryngeal nerve and respiratory centre are thus stimulated, and in man remarkable effects have been produced, more than one person having recovered after apparent respiratory arrest extending over an hour. A small apparatus worked by elec- tricity has been made to carry out the process. Impending Cardiac Syncope is indicated by irregularity of the pulse, widely dilated pupil, weak heart's action, cessation of haemorrhage, or the escape of a few drops of dark-coloured blood from the seat of incision. The head should immediately be lowered as far as possible, artificial respiration commenced, cold water dashed on the head, the chest wall smartly slapped, and if time permit, subcutaneous injections of sulphate of strychnine or ether should be given. Cardiac syncope may also be combated by intermittent pressure on the heart region, at the rate of 120 to 140 times per minute, or by the intravenous injection of warm normal salt solution. Hobday recommends small doses of prussic acid. Rosenberger believes that in man heart failure is due to stimulation of the vagus, owing to irritation of the respiratory mucous membrane by the chloroform vapour ; he recommends previously painting the membrane with, cocaine solution. The precaution is unnecessary in horses. In proof of the irritation produced, however, one may often note in well-bred horses certain symptoms of sore throat, such as coughing, etc., during the few days next succeeding the operation. Recovery usually occurs without treatment. Administration in the standing position. As anaesthesia by chloroform is generally preceded by a short excitation period, during which the animals neigh, become uneasy , and often struggle violently, casting by hobbles or ropes, or the employment of an operating table is almost unavoidable. This, of course, is a drawback, especially when an operating table is not available, and if general anaesthesia could always be carried out in the standing position it would prove a great convenience. In the country, where a field or paddock is convenient, horses may be anaesthetised in the standing position bv the use, preferably, of Cox's muzzle. The animal is held by a strong head collar, or halter with a long shank, a sponge charged with one to one and a half ounces of chloroform is placed in the inhaler, and the horse is led slowly in a circle until he sinks to the ground, when his legs can be secured with hobbles or ropes. Violent struggling is exceptional and there is little danger of spinal injury. ANESTHETICS. 51 Partial anaesthesia in the standing posture is sometimes resorted to in shoeing vicious horses. To succeed, the horse's head mast be firmly secured to a ring in the forge wall, as greater danger is to be feared from the animal becoming loose than from throwing itself down during the period of excitement. The writer has found that many animals will stand quietly until the corneal reflex becomes quite languid or almost abolished. This is the best condition for shoeing troublesome horses. Morphine and Chloroform. When morphine is previously ad- ministered the animals sometimes show considerably more excite- ment than when chloroform alone is employed ; and as, generally speaking, the preliminary use of morphine neither lessens the pre- anesthetic period nor decreases the amount of chloroform required, it is rather a drawback than a help. Chloroform and ether mixtures present no advantages over chloroform alone, except in cases of heart affection. Atropine, Morphine and Chloroform. To facilitate the throwing of restive horses and to save chloroform, Almy and Desoubry recom- mend a subcutaneous injection containing morphine hydrochloride (If grain), neutral sulphate of atropine ( T h grain), and distilled water (2i drachms). After an interval of half an hour the horse is cast and chloroformed. Ether was the first and, in man, remains the favourite anaesthetic. It is administered in progressive doses from a sponge, tampon of tow, or linen compress, or by means of Cox's or Carlisle's inhaler. An ordinary deep leather bucket muzzle is a very good substitute, provided care is taken to prevent the liquid coming in contact with the mucous membrane of the nostril. If necessary, inhalation is occasionally stopped, and when surgical anaesthesia is complete the dose is considerably reduced. During the whole time respiration and the reflexes must be closely observed. The horse having been cast, anything which might impede respiration, or compress the larynx, the lower portion of the neck, or the thorax, is removed. If Cox's muzzle be employed the procedure is precisely similar to that in giving chloroform ; other- wise a linen pad about eight to ten inches square is placed over the nostrils, and ether dropped on it in small quantities. The distance from the nostrils regulates the rapidity of administration and the amount given. The mucous membrane of the upper respiratory passages being irritable, considerable excitement is at first produced ; the animal neighs, struggles, and is sometimes very violent ; respiration and K 2 52 GENERAL ANAESTHESIA. circulation are accelerated. This stage sometimes lasts for ten minutes, and is succeeded by that of surgical anaesthesia. The quantity of ether used is often considerable, from ten to twenty fluid ounces, sometimes even more. Recovery is slower than after chloroform. Though less dangerous than chloroform, ether is not, as some suggest, absolutely innocent, and has claimed a number of victims in human surgery. Nevertheless Gurlt's statistics show the mortality from chloroform to be fifteen times greater than that from ether. Anaesthesia can be produced by the introduction of ether vapour into the rectum. It was tried first on animals by Dupuy and Thiernesse, and has been recommended by Cagny for the purpose of producing a certain degree of drowsiness in horses to facilitate casting or to permit of trifling operations in the standing position. The method is simple ; a flask or tube with a narrow neck is partially filled with ether ; one end of a rubber tube is slipped over the neck, and the other end introduced into the rectum. The flask is placed in water heated to 120° F. Ether vapour is at once given off, enters the rectum, and is absorbed by the mucous membrane. One and a half to two ounces of ether are sufficient. Experience does not show this method to have any marked advantages. In place of partial anaesthesia active excitation often follows. Such violent expulsive efforts are sometimes made as to produce rectal prolapse. In man cyanosis, collapse, and even a kind of asphyxia have resulted. The uncertainty and serious inconvenience of this method have prevented its being commonly adopted. Mixed anaes- thesia, produced by the injection into the rectum of ether vapour, and preceded by the subcutaneous administration of morphine and chloral, is slow in its effects and of little practical utility. In English human surgery a favourite method is to obtain anaes- thesia with nitrous oxide and maintain it with ether. The method has many advantages, and has come largely into use. Chloral is usually injected intra-venously, alone or after hypo- dermic injection of morphine. Intra-venous injection of 20 per cent, solutions produces very rapid and complete anaesthesia. Though declared dangerous by human surgeons, this method has been recom- mended in France and Denmark for the horse, on account of the ease with which injections can be made into the jugular. The injection, which may be of any strength between 10 and 20 per cent., must be freshly prepared, and the best vehicle is physiological saline solution. Intra-venous injection requires very special precautions. The ANESTHESIA BY CHLORAL. 53 point of operation must be thoroughly disinfected, and all instru- ments should be sterilised. Everything being ready, an assistant compresses the vein low down in the jugular furrow ; the operator then draws the skin in the direction of the head with one hand, while with the other he thrusts a needle or fine trocar into the distended vessel, taking a very oblique course from above down- wards, i.e., almost parallel with the vessel. Humbert recommends operating in two stages, first dividing the skin, then, after having raised the vein, introducing the needle or trocar. When the opera- tion is done standing he chooses by preference the right jugular. The discharge of a jet of blood through the cannula when the trocar is withdrawn shows that the vein has been penetrated. An assistant holds the cannula firmly, and inclined towards the general line of the neck. The operator next introduces into the opening of the cannula a special metal plug comiected to a rubber tube, which slips over the nozzle of the injecting syringe, and opening the tap injects the necessary quantity of chloral solution ; needless to say, great care must be taken not to inject air. The operation concluded, he frees the cannula from the rubber tube, allows a little blood to escape, and quickly removes the cannula, supporting the skin mean- while with the fingers of the left hand. Colin gives the dose as two and a half to three and a half drachms ; Arloing three to six drachms ; and Nocard one and a quarter drachms per hundred pounds of body-weight. Anaesthesia appears almost immediately. It is more or less profound, and continues for a greater or less time according to the amount of chloral injected. In a few seconds the animal is asleep, the muscles are completely relaxed, the mucous membranes slightly cyanotic, and the respiration and circulation, though disturbed for a moment, rapidly recover their normal rhythm. The animal recovers slowly, remaining stupefied for a time, and sometimes suffering from general trembling of the body muscles. At the end of half an hour to two hours the horse rises, resting for a time on its haunches. Movement of the hind limbs is irregular and uncertain. This weakness sometimes persists for one or two hours. When the dose has been too large, or the subject is specially susceptible to the action of chloral, the sleep is very deep, the mucous membranes become darker and darker in colour, the pupil dilates, respiration and circulation become slower and slower, the tempera- ture falls, and death may result. If the operation be not performed antiseptically, if the opposite coat of the vein be injured when introducing the cannula, or if the 54 ANESTHESIA BY CHLORAL. solution obtain 'entrance to the perivenous tissue, grave results almost always follow. The majority of those who have tried this method have had at least some cases of phlebitis, and, in consequence, have abandoned it. Phlebitis usually appears between the second and fourth days : a swelling, sometimes circumscribed, sometimes diffused, occurs in the jugular furrow. {Suppuration follows ; frequently a portion of tissue becomes necrotic. In one case mentioned by Cadiot the vein was destroyed throughout almost the entire length of the neck. Furthermore, chloral acts as a vaso- dilator, increasing haemorrhage during operation. Finally, although it has been little used, chloral is responsible for a considerable number of deaths. Moller killed a number of horses by injecting twelve and a half drachms in solution. As the horses were not weighed, it might be said that this dose was too large, but Cadiot has had a death with the prescribed dose, where the quantity administered did not exceed one and a half drachms per hundred pounds of body- weight. Fifteen to twenty minutes after administration, when the operation Mas almost complete, respiration ceased, and a few seconds later death resulted, despite efforts made to establish artificial respiration. Intra-peritoneal injections of chloral are made through the flank. A ten per cent, solution in physiological saline is used. The operation is without danger, and is simpler and more convenient than intra- venous injection. Anesthesia is produced in ten to fifteen mmutes and lasts a long time. Recovery can be hastened by a subcutaneous injection of pilocarpine. Administered by the mouth in doses of ten to twenty drachms diluted solutions of chloral produce drowsiness, loss of co-ordination of movement, but not complete anaesthesia. The method, however, is of value in practice. Chloral and Morphine. To avoid the accidents resulting from intra- venous injection of chloral Cadeac and Malet associated chloral with morphine. They claim to produce complete anaesthesia by subcutaneously injecting a solution of fifteen grams of hydrochloride of morphine, and at the end of ten minutes giving an enema containing twenty to twenty-five drachms of chloral. Anaesthesia is not always produced. It appears slowly, and sometimes only after prolonged excitement. Esser recommends this method where chloroform is contra-indicated. Morphine, in the form of subcutaneous injection, has been recom- mended to quiet small animals, and in the horse to produce slight anaesthesia for trifling operations in the standing position. According ANESTHESIA IN RUMINANTS AND SW'INE. 55 to the animal's size the dose varies from three to seven grains. In certain horses morphine produces somnolence and more or less pro- nounced relaxation of muscular tissue. Irritable or even dangerous animals become quiet and easy to handle. Others, however, even after large doses, show excitement lasting several hours. The patients act violently, exhibit disordered movements, kick and thrust their heads against the wall as in indigestion complicated with brain mischief. Morphine must, therefore, be considered uncertain as an anaesthetic ; nevertheless, it renders some service, and in small doses is devoid of danger. Opium, or Indian hemp is, however, usually preferable. ANAESTHESIA IN RUMINANTS AND SWINE. Except in cases of difficult parturition general anaesthesia is seldom resorted to in ruminants or in the pig. Tabourin and Saunier, who made a long series of experiments with chloroform and ether, came to the following conclusions : — 1. That in oxen, ether produced anaesthesia without difficulty. 2. That the animals succumbed to its action more readily each time anaesthesia was repeated. 3. That chloroform was so much more energetic than ether as to warrant its entirely displacing the latter, despite its higher price. Given by the mouth 12 to 18 fluid drachms of chloroform only produced incomplete anaesthesia. Frohner failed to obtain any anaesthetic action from doses of 10 drachms of chloral ; given by the mouth, 6 to 10 drachms produced unsteadiness of the hind quarters in fifteen minutes ; 12 to 18 drachms, however, caused the animals to fall and lose consciousness and sen- sation ; unconsciousness lasted three hours. Negotin recommended this method and dose. Guinard found morphine useless in ruminants, and especially in goats ; it failed to produce even a sedative effect. Goats are not injured by 400 times the full dose for man. Malzew gave ten oxen chloroform in combination with morphine. Two or three grains of morphine were subcutaneously injected, and three to twelve minutes later chloroform was administered. In seven cases anaesthesia commenced after the lapse of ten to forty minutes, in three it could not be induced. From 4 to 19 fluid drachms of chloroform were used. On return of consciousness none of the oxen showed anything abnormal. Goats and sheep are easily anaesthetised in five to ten minutes with 1\ to 5 fluid drachms of chloroform. 56 ANESTHESIA IN THE DOG AND CAT. In general the above also applies to swine, and chloroform would probably prove the best material ; Negotin found it harmless. Harms succeeded in abolishing sensibility to pin-pricks in ten minutes by giving benzine vapour. Chloral hydrate is often given to cows when calving, in order to dull labour pains ; complete anaes- thesia is seldom necessary. As, however, in the event of operation failing oxen may after- wards require to be slaughtered, alcohol is usually preferred to any substance which might taint the flesh. Most practitioners give a large dose of whisky or rum ; in the case of oxen, one to two pints. In five to ten minutes the action begins, and as intoxication proceeds the muscles relax. ANESTHESIA IN THE DOG AND CAT. Ether or Chloroform may be used ; the latter is preferable. Respiration may take place by either the mouth or nose, but it is dangerous to forcibly close the jaws, especially by muzzling the animal with tape. Guinard lays special stress on the need for keeping the dog's mouth open while giving chloroform ; given by the nose alone chloroform is apt to produce so active a stimulation of the vagus as to sometimes inhibit the heart's action. The dog is placed on its chest or side, the jaws opened, or fixed in an open position by a gag. Chloroform can be given by applying to the animal's nostrils a pad of tow or a small sponge moistened with chloroform. Another method is to form a cone of stout brown or blotting paper, at the bottom of which is placed a small loose ball of cotton wool to receive the chloroform. A conical muzzle, like Krohne's for human use, or an ordinary Junker's inhaler is probably the most convenient apparatus, though necessarily more costly than the paper cone. Whatever the method adopted, ad- ministration should always be slow. Ether is given in a similar way, but the excitation period is longer, and the slumber produced less deep. On the other hand, ether anaesthesia may be prolonged for considerable periods without danger. Hueppe claims to have produced anaesthesia in dogs by injecting 2\ drachms of ether into the external ear. To obtain more rapid narcosis, and diminish danger of collapse, morphine has been recommended hi combination with ether or chloro- form. Moller first injects from three quarters to one and a half grains of hydrochloride of morphine hypodermically, and after a short interval gives ether in the usual way. GENERAL ANESTHESIA. 61 Cagny administers ether vapour by the rectal mucous membrane. Its action, however, is uncertain, and it sometimes causes violent straining. As in the horse, intra-venous injection of chloral is dangerous. Morphine in the form of subcutaneous injection, and chloral in enema, have been advantageously combined. The dose of morphine is at the rate of two minims of a 2 per cent, solution, and of chloral seven and a half grains, per pound of body-weight. Roucher has slightly modified this method. The bowel is cleared with a soap and water or glycerine enema, and a subcutaneous injection of morphine in the proportion of jV.th grain of hydrochloride of morphine per pound of body-weight administered, followed by an enema of one drachm of chloral hydrate in linseed emulsion. If necessary the dose may be repeated in seven to eight minutes ; very large dogs may require a third, or even a fourth. The disadvantages are the same as in the horse. Anaesthesia is slow and haemorrhage abundant. Richet has recommended intra-peritoneal injections of chloral alone or associated with morphine. Injected into the peritoneum chloral produces complete anaesthesia in about ten minutes. The injection is made with a Pravaz's syringe, the greatest care being taken in regard to asepsis. When well diluted, chloral is tolerated by the peritoneum. Morphine added to the chloral prolongs anaes- thesia to about one hour without danger of syncope. In this method the doses are, hydrochloride of morphine 02 grain, chloral four grains, per pound of weight. The method, however, does hot seem to have proved permanently successful, dangerous complications sometimes occurring. Frohner regards urethane as one of the best agents for the dog, and has tried paraldehyde with good results. Desoubry gives from 2,2 to 30 grains of sulphonal to dogs of 40 lbs. body-weight, and highly praises the method. In the dog and cat, however, the best method probably consists in using chloroform after a preliminary injection of atropine and morphine. The morphine modifies excitement at the commence- ment of anaesthesia ; the atropine prevents cardiac syncope by suspending the function of the cardiac moderating centre and of the arresting fibres of the pneumogastric. The solution is prepared as follows : Hydrochloride of morphine . . .3 grains. Sulphate of atropine . . . . -3 grain. Distilled water 2| fluid drachms. This solution is injected in the proportion of five minims per 58 ANAESTHETICS. pound of body-weight. In twenty to i went y-fivc minutes the solution produces its effect, and chloroform inhalation can be commenced. A drachm or two is sufficient to produce complete anaesthesia, which can be prolonged for one or two hours. The solution used in man is as follows : Hydrochloride of morphine . . U grains. Sulphate of atropine .... 08 grain. Distilled water •. . . . 2| fluid drachms. This solution is also preferable for the dog. Ten minims are given to animals of small size, twenty to forty minims to animals of medium size, and sixty to eighty minims to large dogs. Chloroform is administered at the end of twenty -five minutes. This method produces deep and prolonged anaesthesia. There is no danger of syncope. Langlois and Maurange recommend, for the dog, sparteine, morphine and chloroform. Fifteen minutes before inhaling chloro- form, the dog is given a subcutaneous injection of sparteine sulphate (i grain), and morphine hydrochloride (ith grain). The cat is very susceptible to the action of most anaesthetics. Death may result from giving an overdose, from pushing the anaesthetic rapidly, or from prolonging its action. A convenient method consists in placing the animal under a bell-jar containing a small sponge or a tampon of wadding saturated with chloroform. The animal soon loses consciousness and falls, when it is removed and the operation performed. This method, however, is not without danger ; the period of anaesthesia is short, and if repeated inhalations are given there is some danger of the animal succumbing. A modified Junker's apparatus is preferable. Miiller, of Dresden, confirms the common experience that cats are poisoned in a few minutes if chloroform be given rapidly, although they bear considerable doses of ether very well. Forty-five grains of chloral hydrate in the form of enema also proved fatal. The combination of atropine, morphine and chloroform, as given above, may be employed, but the cat, being extremely sensitive to the action of morphine, which in it produces great excitement, the dose should not exceed '002 grain instead of -02 grain per pound of body-weight. Guinard recommends another method permitting of prolonged anaesthesia. He gives a hypodermic injection of hydrochloride of morphine at the rate of "02 grain per pound of body- weight, and at the end of a quarter of an hour to twenty minutes, when excitement diminishes, he places the cat under a bell-jar with a sponge saturated with chloroform. The animal should be removed LOCAL ANESTHESIA. 59 when anaesthesia first appears, but inhalation is best continued for a few moments afterwards. Thus obtained, anaesthesia can be kept up for forty-five minutes. The excitement due to morphine reappears as anaesthesia diminishes, and may persist for some time. Negotin recommends Billroth's mixture (chloroform 3 parts, ether and alcohol aa 1 part) or Wachsmuth's (chloroform 5, rectified oil of turpentine 1 part) for dogs and cats. The ordinary A.C.E. mixture (ether 3, chloroform 2, alcohol 1) is better than ecpial parts of ether and chloroform. Negotin had indifferent results in carnivora and horses with bichloride of ethylene, and in cats and dogs with bromoform. Monkeys may be placed in a cage closely covered with a cloth, and containing in one corner a tampon of cotton wool saturated with chloroform. The animal at first struggles, and then begins to fall about the cage or to lean against the walls, at which stage it is removed ; if the operation lasts for some time a further inhalation is given. Birds may be placed under a bell-jar containing a sponge or cotton-wool tampon saturated with chloroform. One edge of the jar may be slightly raised to allow air to enter. Hering states that birds may be hypnotised by placing the head under one of the wings, and then rapidly turning the bird's body several times around its long axis. Conclusions regarding General Anaesthesia. The above conclusions may be summarised as follows : — ■ 1. For horses the best anaesthetic is chloroform (inhaled) in doses of 1 to 8 fluid ounces ; average dose, say, 3 ounces. 2. For oxen : chloral hydrate, in doses of 12 to 20 drachms, or whisky, brandy, or rum in doses of 1 to 2 pints. 3. For sheep, goats, and swine : chloroform (inhaled) in doses of 2i to 5 drachms. 4. For dogs and cats : morphine (subcutaneously) in doses of •75 to 15 grains, or equivalent doses of morphine and atropine, followed by inhalations of ether, or chloroform given in small, care- fully increased doses, or a mixture of chloroform, ether and alcohol. LOCAL ANAESTHESIA. The dangers of general anaesthesia have stimulated the search for means of rendering insensitive the region of operation alone. Prolonged compression of tissues and mediate compression of the 60 cocAiNii. nervous trunks supplying the part are very imperfect methods. For a long time ice refrigerating mixtures and ether spray were exclusively used. Cocaine was afterwards discovered, and soon became popular. Eucaine, novocaine, and stovaine are also used ; and when the operation is likely to be accompanied by moderate bleeding, solution of adrenalin is added to the anaesthetic before injection. Anaesthesia by Cold. The prolonged action of cold renders super- ficial tissues bloodless and diminishes or even abolishes sensibility. Refrigerant mixtures have been used in operations like neurectomy. Crushed ice and salt, mixed in the proportion of 2 to 1. are packed into a long bag and applied to the region of operation. In a few minutes, especially if the bag is pressed firmly into contact with the part, the skin becomes cold, firm, and insensitive, and incisions unless deep neither provoke pain or haemorrhage. The anaesthesia, however, is of short duration, and operation must be rapid. By projecting an ether spray on the parts the temperature is soon so far reduced that trifling operations may be performed without pain. The action is rendered more rapid and complete by previously applying an Esmarch bandage. It is difficult, however, to render inflamed parts insensitive, and for this purpose the usual refrigerating mixtures are preferable. Methyl bichloride, successfully used in man for troublesome neuralgia, is almost too active, and though rendering the skin insensitive in a few seconds not infrequently freezes it, causing more or less extensive necrosis. Local Anaesthesia by Cocaine. Cocaine is almost insoluble in water, but the greater number of its salts dissolve freely. The most frequently employed is hydrochloride of cocaine of 1 to 10 per cent, strength. The addition of a trifling amount of bichloride of mercury insures the solution keeping. Reclus recommends the following formula : Hydrochloride of cocaine . . 1| grains. Sublimate . . . . . "03 grain. Distilled water . . . . 2 J fluid drachms. A few drops of this solution placed between the eyelids render the superficial layers of the cornea insensitive in three minutes. By repeating the application at two-minute intervals the cornea, the conjunctiva, and eyelids are often completely insensitive in less • than ten minutes, and anaesthesia lasts a quarter of an hour. The pupil dilates, but as a rule the iris is not rendered insensitive unless the injection is made into the anterior chamber. By this method puncture of the cornea and removal of foreign bodies fixed in the LOCAL ANAESTHESIA. 61 conjunctiva are rendered easy. Five or six subconjunctival injections made around the ball of the eye permit the eye itself to be removed without great pain. Cocaine acts equally well on other mucous surfaces, and under certain conditions may be useful in painful inflammations of these membranes. The most recent experiments appear to show, however, that the blanching and anaesthesia are followed by congestion of the parts, and the use of cocaine in gargles, etc., for inflamed pharynx has been abandoned in human surgery, the after effects being bad. Solution of cocaine, 2 to 5 per cent., is frequently employed subcutaneously to assist in the diagnosis of obscure lameness in horses. By a series of small injections along the course of a proposed incision operation is rendered painless, provided the seat of operation be in a mucous membrane or in the skin. A Pravaz's syringe fitted with a long fine needle is used, the needle being inserted into the subcutaneous connective tissue, or, better, into the thickness of the epidermis, following the direction of incision. As the needle is gradually withdrawn the piston is slowly pressed home, leaving the track filled with fluid. The anaesthetic qualities of cocaine are increased by previously injecting morphine. Its toxicity varies according to species. In the dog the dose varies from § to 1£ grains. Strong solutions offer no advantages and are dangerous. Cocaine solutions of whatever strength, lose, more or less completely, their anaesthetic quality on becoming acid, but this can be restored by neutralising the liquid. Local Anaesthesia by Infiltration. Schleich produces local anaes- thesia by causing artificial oedema in the region of the operation. He performed amputation and even laparotomy successfully. He showed that it is not necessary to inject strong solutions of the anaesthetics which might produce poisoning, but that quite weak solutions, even a 2 per cent, solution of chloride of sodium, suffice, and that in all cases of anaesthesia, other factors than the mere chemical constitution of the substance play an important part. The injection of fluids under fairly high pressure into the skin and sub- cutaneous tissues renders the whole area affected completely insensitive. Should the tissues be cut through no blood flows. This method produces anaesthesia by the co-operation of four factors — the pressure induced by the mechanical action of the liquid, cold due to the temperature of the solution, anaemia caused by the cold and pressure, and a chemical change produced in the nerve endings. The undermentioned formulae, which have been used in human practice, have been tried on horses and dogs by 62 LOCAL ANESTHESIA BY INFILTRATION. Podkopajeu and Negri, who recommend them for their simplicity, harmlessness, and cheapness. The condition lasts, however, for not longer than twenty minutes. Schleich's experiments showed that the best results attended the use of a combination of cocaine, sodium chloride, and morphine. He recommends the following formulae for use in man : /Hydrochloride of cocaine .... 0*20 . . ! Hydrochloride of morphine .... 0-02 Strong solution iChlorideofsodilim Q . 20 IWater 100 7 fluid drachms injected at each operation. /Hydrochloride of cocaine . . 0*10 _., , , , ' Hydrochloride of morphine . . 0-02 Moderately strong solution - CMoride of godium _ _ _ . 20 ( Distilled water .... 100 14 fluid drachms injected at each operation. /Hydrochloride of cocaine . . . . 0-o| .., . . ,. Hydrochloride of morphine .... 0'005 Weak solution jC h lorideof sodium .2o (Distilled water 100 Use up to 140 fluid drachms at each operation. He renders even the first prick of the needle painless by previously spraying the point of puncture with a mixture of four parts of sulphuric ether and one part of petroleum ether. Mucous membranes are rendered insensitive by dabbing with 10 per cent, carbolic solution, or with a solution of cocaine. The needle is slowly introduced into the skin itself in a direction parallel with the surface, and must not enter the subcutaneous tissue. As soon as the point has travelled a quarter to half an inch beyond the primary puncture the piston is gently pressed, causing a bleb to rise in the skin. The syringe is then slowly withdrawn, and again introduced within the periphery of the little blister previously produced. This is quite painless, as the area has now become insensitive. A further blister is thus produced, and the operator proceeds in the same way until a chain of blisters is formed covering the entire length of the incision presently to be made. Each of these points of artificial oedema is insensitive. The method succeeds, not only in the case of skin and mucous membranes, but in serous and synovial membranes, muscles, nerves, and the periosteum. Even bones and the bone medulla can be rendered insensitive by subperiosteal injections. Deeper-lying tissues can, of course, only be rendered insensitive after the more superficial have been so treated. The condition persists for fifteen to twenty minutes ; should an operation last longer the process must be repeated. In preparing for the insertion of sutures for instance, LOCAL ANAESTHESIA BY INFILTRATION. 63 the needle of the syringe is passed from the cut surface towards the skin, so that the path which the suture^ needle will afterwards take is rendered oedematous. The bleeding from tissues thus rendered oedematous is remarkably slight ; on incision the injection fluid is first of all discharged without admixture of blood, then little points of bright arterial blood appear in the fluid from the wound. According to Schleich the injection of distilled water also induces local anaesthesia. A solution of 2 per cent, chloride of sodium sets up local anaesthesia without previous hyperaesthesia ; 3 per cent, solutions of sugar produce more or less pronounced anaesthesia. Pietro Ghisicui has experimentally studied at the Turin Veterinary School the results obtained by the above-mentioned formulae, and by distilled and sterilised water. The quantity of cocaine solution or of distilled and sterilised water employed varied ; generally he used from 2 J to 16 drachms of the strong solution, 3 fluid ounces of the moderately strong solution, 4 \ fluid ounces of the weak solution, instead of \\ to 4 \ fluid ounces of water. He noted a fleeting hyperaesthesia during the operation, the tissues became turgescent, infiltrated, oedematous, and anaemic. The oedema produced by the water and by the solution of Schleich disappears after eight or nine hours. The vitality of the tissues is unaltered, and cicatrisation takes place regularly. Complications, such as stupefaction, nervous or functional troubles, etc., have not been observed. From twenty-two experiments made with water, and the same number with Schleich's solution, the author draws the following conclusions : Anaesthesia by infiltration should be more common in veterinary practice. Schleich's method is very useful, practical and cheap. Solutions of cocaine may be replaced by distilled and sterilised water, with which complete local anaesthesia is obtained, lasting as long as that produced by Schleich's solution. In laparotomy water and cocaine solutions have an unsatisfactory effect, apparently due to the ready distension of the tissues, which prevents the requisite action of the fluids. Bayer tried Schleich's method in animals, and with such good results that he recommended it strongly, especially where casting the horse might be inadvisable. As an experiment, he made an incision about four inches long through the mucous membrane of the tongue and then sutured the wound. He also trephined the superior maxillary sinus without causing any apparent pain. The horse was operated on in the standing position, and was not restrained 64 SPINAL ANAESTHESIA. by twitches or other appliances. In another case, having cast but not chloroformed or twitched the horse, he divided the median nerve without causing any struggle. In this instance the nerve sheath was injected. At the point of operation the nerve was insensitive, but pressure with the needle at any spot beyond the cedematous zone produced lively reaction. Employing infiltration Moller successfully performed an extensive operation for hernia on a horse without casting. This method is particularly useful in dogs, which seem specially susceptible to the action of chloroform, and not infrequently die as a consequence of prolonged administration. SPINAL ANESTHESIA. The event of the surgical year 1900 in Paris was undoubtedly the impetus given by Tuffier to the method of inducing anaesthesia by medullary injections of cocaine, a suggestion previously made and acted upon by Bier, of Kiel, Seldowitsch, of Russia, and Corning, of Chicago. Tuffier was first led to use it as a means of relief in the case of a young man suffering from an inoperable osteosarcoma of the ilium for which morphia had been employed without benefit. The result of the injection of cocaine was striking. The patient, who was crouching down in the position of greatest ease, felt the pain disappear in a few minutes, and was even able to rise. There was at the same time absolute anaesthesia reaching to the umbilicus. Unfortunately the relief lasted only a few hours, and the injection was repeated two days later with similar effect, pressure over the tumour for some hours causing no pain what- ever. A few days later a similar injection was tried for a patient with a recurrent sarcoma of the thigh, and to Turner's surprise he was able to remove the tumour completely with abso- lutely m pain to the patient, the anaesthesia lasting over an hour. At first, therefore, used only in the surgery of the lower limbs, Tuffier rapidly extended its use to operations upon the perinaeum, the rectum, the anus, the bladder, the ureter, the kidney, and such laparotomies as hysterectomy, removal of the appendix, and even gastro- enterostomy. Finally, removal of the breast has been effected with complete anaesthesia. Convinced of the absolute harmlessness of the injections, Tuffier then used them in general gynaecology, and per- formed such operations as hysteropexy, drainage of salpingitis, ovariotomy, vaginal hysterectomies, etc., with equal success. Intra-spinal anaesthesia is now widely employed in human surgery. Cocaine has been replaced by stovaine, tropacocaine, or novocaine, and the injection is made up with sterilised water containing sodium SPINAL ANAESTHESIA. 65 chloride, or five per cent, glucose, and sometimes a few drops of a weak solution of strychnine are added to counteract the depressing effect of the anaesthetic. To promote diffusion Barker and other English surgeons recommend that the density of the injection should be slightly greater than that of the cerebro-spinal fluid (T0070). Lumbar anaesthesia has been tried in the horse, ox, and dog by Cuille and Sendrail, of the Toulouse Veterinary School. They report that their experiments have given complete satisfaction. Horse. They employ a trocar about 5 inches long by iV of an inch in diameter. The place where the puncture is made is found midway along a line joining the internal angles of the two ilia. Implanted vertically at this point the trocar enters the neural canal, traversing the lumbo-sacral space. It is the only accessible spot ; further forward the vertebral laminae are too close together or imbri- cated. Penetration of the subdural space is indicated by the escape of cerebro spinal fluid through the cannula. During the operation the animal scarcely moves. The application of a twitch and the lifting of a fore-foot are the only precautions required. Disinfection of the cutaneous surface, sterilisation of the trocar, syringe, and solution, are absolutely necessary. First experiment. Aged mare. Injection of 1 fluid drachm of 2 per cent, solution of cocaine. Five minutes later the subject rocked slightly ; when made to move she showed weakness behind, and went over on her side. The students practised neurectomy on all four legs. Cutting through the nerves of the hind-limbs caused no pain, but section of the nerves in the fore-limbs produced pain, manifested by struggling of all the limbs. In the second case the operation of ovariotomy was performed without any exhibition of pain. Third experiment. Aged mare, medium size. Injected 30 minims of cocaine solution. The gait was like that of the former animal. Ten minutes later ovariotomy was performed without any movement whatsoever (" dans le calme le plus parfait "). The sensibility of different parts of the hind-limbs, flanks, and lower aspects of abdomen was tested by pyropuncture ; there were no signs of pain. Plantar neurotomies were performed upon the hind-limbs forty minutes after the injection without pain, the animal lying down. Bovines. The same trocar as for the horse was used. Puncture was made at the same point. Leaving aside the toughness of the skin, the operation is easier than in the horse, the lumbo-sacral space being a little wider. Sixth experiment. An old Lourdes cow. Injected 75 minims R.S. F 66 SPINAL ANAESTHESIA. of 2 per cent, solution of cocaine. Three minutes later the animal flexed her hind-limbs ; after five minutes she showed weakness, and for a short time literally sat down ; then she lay down on her side. Pricked deeply in different parts of the hind-limb, she did not move. When the prickings were done in the fore-quarters as far as the line of cartilages of the asternal ribs, she showed pain. An hour later the animal got up voluntarily. The spinal cord, spinal meninges, and cauda equina were perfectly normal. Dog. The best point for the operation is again in the lumbo- sacral region, taking the same landmarks as before. A hollow needle of a Pravaz syringe, 2\ inches long and z } fi inch in diameter, is the most suitable. Ninth experiment. A male mastiff of average size received 30 minims of the cocaine solution. The animal stood up, the head being kept firmly in position by an assistant, and did not resist the operation. Several minutes later he fell upon his hind quarters with the limbs extended, and progressed by means of the fore-limbs as an animal attacked with complete paraplegia. Sensibility was tested by the aid of the zoocautery, and was found to be non-existent behind the hypo- chondriac regions, but preserved in front. Forty-five minutes later the animal got up, and sensation only commenced to reappear at the end of an hour. The dog then went to his kennel and ate his food with relish. Tenth experiment. Made upon the same animal the day following the previous experiment. The animal did not appear to have suffered from the experiment of the previous evening. He received 15 minims of the solution. Five minutes later the gait was somewhat altered, but walking was still possible ; the analgesia extended over the same area as on the previous day. An hour later, the condition of the animal being apparently normal, 15 minims were injected in the region of the bulb .in the occipito-atloid space without puncturing the medulla. A few seconds later the animal became helpless ; he could only advance by crouching on the ground with his paws in front of him, moving upon his sternum. He vomited. The analgesia involved the anterior part of the body, the head excepted. Two hours later he progressed more easily, and went to his kennel, where he ate his food. During the succeeding days and for a month after- wards he showed nothing abnormal. Killed at the end of the month, no trace whatever could be found of the injections. All his organs were perfectly healthy. These and other experiments show in a convincing manner that limited anaesthesia produced by cocaine injected into the neural canal is applicable in veterinary surgery, and that, with proper ANTISEPSIS AND ASEPSIS. 67 precautions, there is no danger. The doses used were fifteen to seventy -five minims of a 2 per cent, solution of cocaine for the horse or ox. For dogs fifteen minims should not be exceeded. Solution of stovaine (5 per cent.), dog, M. 20 to M. 30 ; Cat, M. 10 to M. 20 ; horse, 7>j to ojjss. IV.— ANTISEPSIS AND ASEPSIS. "During the first half of the last century infection of exposed wounds was attributed to impure and exhausted air, especially to the hospital atmosphere and to air charged with the miasma of putre- faction. Pasteur and Tyndall corrected the truth of this idea, and showed that it is not the air itself which has injurious properties, but only the germs it carries in suspension. Sterile organic fluids exposed to the atmosphere immediately begin to ferment, but pro- vided they be kept from contact with all but optically pure air filtered through cotton wool they undergo no change. It was there- fore concluded that decomposition and putrefaction are due to little animate bodies, suspended in the atmosphere, — i.e. germs or microbes — which under favourable conditions break down organic substances. Save for micro-organisms there would be no decomposition and no putrefaction. Extending the logical process, Lister was of opinion that the same changes went on in injured tissues exposed to the action of air as occurred in organic liquids. Septic changes in wounds therefore represent a kind of fermentation. In 1865 Lister, inspired by Pasteur's work on fermentation, began those experiments which eventuated in the formulation of his " anti- septic method " ; while in 1870 Guerin, following up the same work and that of Tyndall, invented his surgical dressing. Guerin applied to wounds the experimental conditions necessary for preserving organic materials from change when in contact with the air, shielding the injured tissues by thick layers of cotton wool. Lister, on the other hand, sought to destroy microbes present in the wound or introduced during operation, by means of chemical substances. Lister first rendered the wound aseptic and afterwards protected it by a germicidal barrier. At first Guerin did not seek primary union of the wound, only attempting to reduce the discharges and to avoid infection. Bleeding having ceased, he washed the wound with tepid water, afterwards with a mixture of water and camphorated alcohol. In some cases he sutured the wound and cut the threads short, covering the parts with several layers of wadding. In extensive operations on the 68 DEVELOPMENT OF ANTISEPSIS. limbs the region was enveloped in many layers of wadding suitably affixed. The outer bandages were applied tightly, and if during the next few days the degree of compression was considered insufficient, or if the discharges penetrated the whole thickness of the wadding, fresh bandaging was resorted to. At first the dressing was left in position for twenty to twenty-five days, later it was replaced at the end of twelve to fifteen days. As a rule on removing the first dressing the wound was found to be granulating throughout. With a second dressing left in position for eight to ten days cicatrisa- tion was complete. To obtain primary union various modifications were made in this method. Thus bleeding was more thoroughly checked, and the lips of the wound carefully closed with deep sutures of some material like catgut which would gradually disappear. Despite its many advantages this dressing of cotton wool concealed the state of the wound. The thermometer certainly gave indications of unfavourable changes, but as considerable fever sometimes occurs even when wounds are doing well, time was lost, and it was not infrequently necessary to remove the dressings, thus exposing the patient to danger. Further, although atmospheric germs could not enter the wound through the layers of cotton wool, those already there or introduced during operation were not destroyed, and frequently multiplied with great rapidity. Compared with the older dressings that of cotton wool constituted an immense stride in the surgical art, but, nevertheless, its use did not become general. The greatest success was reserved for Lister's dressing, which was more practical and also more certain in its results. To prevent infection Lister sought to destroy all infectious materials in and around the wound as well as in the neighbouring air. Completing this process, he took care that the hands of the surgeon and his assistants, the instruments, sponges, compresses, and all materials used as dressings should be rendered thoroughly aseptic. The wound having been cleansed of organisms was covered with a material saturated with an antiseptic, and precautions taken to prevent accumulation within it of serosity from the injured tissues. Lister long preferred carbolic acid in solutions of 1 in 20 and 1 in 40. With the strong solution the instruments, sponges, and seat of incision were disinfected, and once the operation was over, the wound throughout. The weaker solution was used for disinfecting the hands of the surgeon and his assistants, and for rinsing sponges and instruments during operation. To prevent the wound being ANTISEPIS AND ASEPSIS. 69 infected by atmospheric germs he introduced an antiseptic spray, the vapour of which covered the entire area of operation. All bleeding was checked, vessels were ligatured with catgut, the threads were shortened, and the edges of the wound brought together with catgut sutures. Rubber drain-tubes were inserted to permit serosity, etc., to escape, and the dressing was then applied. The region of operation was first covered with a strip of protective consisting of oiled silk, the object being to prevent prolonged action of the carbolic solution on the wound, as this proved too irritant. Over the protective was applied carbolised gauze, doubled six or eight times, the last two layers being separated by a layer of mackintosh to prevent the carbolic acid evaporating, and to force the wound discharges to traverse the entire thickness of the dressing before escaping. All these materials were fixed in place by bandages of carbolised gauze. Lister's method of dressing rapidly spread throughout all Conti- nental countries. Though it at once displaced the old methods, it possessed some drawbacks, such as the minuteness of detail required, the time demanded for its application, its high price, and the dangers resulting from the poisonous nature of the antiseptic employed — carbolic acid. While, therefore, respecting the great principles laid down by the founder of the method, surgeons set to work to perfect and especially to simplify its application. Carbolic acid was replaced by salicylic acid, thymol, zinc chloride, corrosive sublimate, bismuth subnitrate, iodine, iodoform, and other anti- septics. Ordinary tarlatan or muslin, soaked for a week in carbolic solution, was substituted for carbolised gauze. The spray was dis- continued as superfluous. Drainage tubes of decalcified bone were suggested, because they became absorbed, irritated the tissues little, and necessitated less frequent renewals of the dressing. The pro- tective was shown to be useless, and drainage was suppressed except when immediate union appeared uncertain. The technique of dressing, the antiseptics, and the strength of solutions have been varied infinitely. Believing that the principal point was to prevent atmospheric germs gaining access to the wound, Guerin paid less attention to disinfecting hands, instruments, and dressings, and his good results were in a large measure due to the habit he had formed of thoroughly washing the hands and cleansing the region of operation and its neighbourhood with soap and camphorated alcohol before opera- tion. In Lister's practice, the most important factor was the rigorous cleanliness of the hands, of the instruments, and of the 70 ANTISEPTIC AND ASEPTIC METHODS. dressings. Antiseptic treatment of wounds might never have survived had not observance of cleanliness largely assisted it. Contrary to the belief generally held when antisepsis was introduced, entrance of air into wounds is little to be feared, and atmospheric germs can be almost disregarded. In veterinary surgery asepsis will probably never obtain the same favour as antisepsis. Strictly considered, however, antisepsis and asepsis do not stand in opposition, but rather form mutual complements of each other; aseptic methods being preventive, antiseptic curative, their association is often advan- tageous. Antisepsis is resorted to when the region of operation includes a suppurating wound, a fistula, or an ulcer, or when reunion by first intention has failed. Antiseptics are then employed to disinfect the seat of operation, the hands, the instruments, and the dressing materials. The aseptic method, on the other hand, is applicable to operations on infection-free tissues which might become inflamed under the action of antiseptics, to cases of limited necrosis and to intoxications ; but if asepsis can be ensured, it is useless to apply to healthy tissues strong antiseptic solutions. Of the two principles — •" antisepsis before and during," " antisepsis before, asepsis during "—the former is preferable in our practice on account of the chances of the wound, the hands, and instruments becoming infected during operation. Even in human surgery, where, thanks to better surroundings and to special apparatus, rigorous asepsis can much more readily be obtained, and where the operator can count on highly skilled assistants, antisepsis nevertheless has many adherents. Wound infection is caused by the presence of pathogenic bacteria, which sooner or later develop and multiply, and by their activity or their products set up irritation of the tissues, inflammation, suppuration, and in certain cases, general infection of the body. Among the micro-organisms causing surgical infections micrococci and bacilli stand pre-eminent. Whilst the former are usually quickly killed by heat and the principal disinfectants, the latter resist to a varying degree, depending on whether they are present in the form of rods or exist as spores. The adult bacilli are easily killed, the spores on the other hand are strongly resistent. Certain spores, like those of tetanus and anthrax, exhibit most extraordinary vitality. When dry, microbes resist the action of heat and antiseptics to a higher degree and for a longer time than when moist. The most convenient method of destroying them is exposure to moist heat. Whilst steam at 212° F. kills the majority of pathogenic microbes, 144° F. 131° F. 140° F. 167° F. 176° F. 131° F. ANTISEPTIC AND ASEPTIC METHODS. 7l the dry temperature required for the same result varies from 290° to 330° F. Moisture considerably enhances the destructive action of high temperatures and of antiseptics. Few pathogenic microbes resist steam heat for more than a few minutes. Many die at 175°, 160°, and even 150° F., but the spores of the tetanus bacillus and of some septic organisms endure higher temperatures than 212° F. without destruction. The following table shows the temperatures at which the organisms of chief surgical interest are destroyed : Staphylococcus pyogenes aureus is destroyed in ten minutes by a temperature of 137° F. >> " albus ,, ,, fj ^ 144° F ,, ,, citreus ,, „ Streptococcus of erysipelas ,. strangles The bacillus of tetanus ., ,, ,, ,, tuberculosis ,, „ ,, glanders Anthrax spores are destroyed in ten minutes by a temperature of . . 212° F. Tetanus spores ,, ,. ., ,, . . 220° F Tetanus spores are destroyed in fifteen minutes by a temperature of 212° F. and in five minutes by a temperature of 240° F. At ordinary temperatures they resist 5 per cent, carbolic solution for more than ten hours. The organism of black-quarter is destroyed in ten minutes by immersion in boiling water. When dry it resists a temperature of 250° F. for ten minutes. Moist anthrax spores are destroyed in a few minutes by a temperature of 212° to 220° F. When dry they are only killed after ten minutes' exposure to a temperature of 240° F. Bacteriological researches and some clinical investigations show that disinfection by chemical agents is not always complete even when concentrated solutions are used. Organic substances, even in thin layers, are not always readily penetrated by liquid antiseptics, and the deeper strata may retain virulent organisms in spite of the prolonged action of such liquids. Chemical disinfectants are there- fore reserved for the seat of operation, and the hands ; instruments, ligatures, drainage-tubes, and other materials used for dressing are subjected to the action of boiling water, glycerine, heated oil, or simply to a high degree of dry heat. The simplest and most practical method is that of boiling in water containing one per cent, of sodium carbonate. Although it does not give absolute security — certain spores resisting even a temperature of 212° F. — it is almost always sufficient. 72 ANTISEPTICS. ANTISEPTICS. Carbolic acid is used in solutions of 1, 2|,and 5 per rent, strength. The 5 per cent, is mainly employed for disinfecting the hands, instru- ments, seat of operation, abscess cavities, suppurating wounds, and sometimes for exciting slight adhesive inflammation when inserting intestinal sutures. It is unsuitable for operation and recent wounds, because it strongly irritates the tissues and produces free serous exudation, thus impeding immediate union. The 2 per cent, solution is suitable for irrigating fresh wounds, and for rinsing the hands during operation. The 1 per cent, solution is used for disinfecting certain mucous surfaces and for obstetrical operations. Sublimate or perchloride of mercury solution is one of the most useful chemical antiseptics. A 1 in 1000 solution destroys bacteria and most micro-organisms in a few minutes (Koch). On account of its irritant and toxic characters many surgeons restrict its use to the disinfection of the skin and vaginal mucous membrane. For other mucous surfaces and for deep wounds they regard it as dangerous. Nevertheless, in weak solution it is valuable for irri- gating surgical and accidental wounds, as it irritates tissues less than carbolic acid. It blackens metallic instruments, destroys their polish, and injures their edge. The strong solution of sublimate is prepared as follows : Sublimate ...... 1 part. Tartaric acid ..... 5 parts. Boiled water 1000 The weak solution contains double the above quantity of water. Solutions of 1 in 3000 to 1 in 5000 can be used for most mucous membranes. As, however, it is decomposed by alkaline salts, distilled water must be used for making solutions, or a small quantity of acetic or salicylic acid should be added to ordinary water before use. To prevent sublimate solutions being decomposed by contact with albumen, five parts of chloride of sodium or ammonium to each part of sublimate are added in preparing them. A convenient method of preparing sublimate solutions is offered by the tablets, etc., manufactured by various wholesale chemists. An excellent material for disinfecting the surgeon's hands is obtained by dissolving two parts of sublimate in 1000 parts of rectified spirit. Frick's wound gelatine for covering wounds after operation is prepared by soaking gelatine in 1 in 1000 sublimate solution, dissolving by heat, and adding a quantity of glycerine equal to one-tenth of the weight of the dry gelatine. It adheres better than collodion. ANTISEPTICS. 73 Chloride of zinc, formerly used for treating unhealthy wounds, is a powerful antiseptic. In 5 per cent, solution it rapidly destroys most spores (Koch), but it is caustic. The 10 per cent, solution is useful for disinfecting fistulae, abscesses, and suppurating or septic wounds. Sochi's paste, consisting of 50 parts oxide of zinc, 50 parts water, and 5 parts chloride of zinc, is used in veterinary practice ; applied to aseptic sutured wounds it forms a kind of protective varnish, replacing a dressing. It is specially useful for wounds about the head and in the upper regions of the body. Permanganate of potash is also a good antiseptic, devoid of toxic jDroperties. It owes its microbicidal powers to the oxygen which it disengages. Producing no irritation it can be used for all wounds, especially those in mucous membranes. A solution of 1 in 1000 is useful for disinfecting the mouth, nasal cavity, vagina, rectum, and serous cavities. A 10 per cent, solution is used for infected wounds and occasionally for the hands. The stain can be removed by plunging the hands into a 10 per cent, solution of hyposulphite of soda to which has been added a few drops of hydrochloric acid. Hydrogen peroxide is a powerful germicide. Mixed with blood or pus it decomposes with effervescence, and is of considerable value as a disinfectant for sinuses and abscess cavities. With normal saline solution hydrogen peroxide is a useful haemostatic. Biniodide of mercury is stated to be thirty times more active than sublimate, and a solution of 1 in 10,000 to 1 in 20,000 is used for disinfecting the vagina and mucous membrane of the uterus. This solution neither irritates the hands, nor the lips of wounds, and does not injure instruments. Iodine is a very active antiseptic ; one part in 7000 destroys both bacilli and their spores (Koch). Iodine, dissolved in chloroform or ether, or as the tincture is largely used for disinfecting the skin prior to operation. Solutions are employed as injections for bursal distensions after evacuation of the contents, and the undiluted tincture is an excellent application for offensive wounds and abscess cavities. Iodoform, long employed for treating wounds and ulcers, is especially useful in checking suppuration. Its action is slow. Being both antiseptic and analgesic it assists cicatrisation, retards decomposition of wound discharges, and diminishes pain. Powdered over the lips of wounds before suturing it does not prevent immediate union. Dusted in a thin layer into wounds with loss of substance it keeps them aseptic for 5, 6, or 7 days, constituting a kind of disinfecting reserve. Its disadvantages are its disagreeable odour and high price, 74 ANTISEPTICS. Three preparations of iodoform are used in surgery, viz. saturated solution in ether, a 10 per cent, emulsion in glycerine, and a 10 to 20 per cent, ointment in vaseline. The glycerine emulsion is useful in the treatment of abscesses, tuberculous cavities, and contused wounds, like those caused by carriage poles, etc. Gauze and wadding impregnated with iodoform are largely used as antiseptic dressings. They contain 10, 20, and 30 per cent, of iodoform. Formalin consists of a 40 per cent, aqueous solution of formalde- hyde. Diluted with four to five hundred parts of water, it becomes a useful disinfectant for the hands, seat of operation, and accidental rounds. Strong solutions are irritant and caustic. Tannoform, glutol and amyloform are respectively compounds of formaldehyde with tannic acid, gelatine, and starch. They form useful dry dressings for open wounds, but are of greatest service when preceded by the application of a liquid disinfectant. Chinosol is a yellow, crystalline powder, derived from coal tar. A solution of one part in forty thousand prevents bacterial develop- ment, and a grain dissolved in six drachms of water is said to be equal in antiseptic powder to a 2£ per cent, solution of carbolic acid. Solutions for surgical purposes vary in strength between 1 in 1200 and 1 in 60. Combined with starch or French chalk chinosol forms an efficient dry dressing. Nitrate of silver of a strength of 1 to 2 per cent., or of 1 per 1000, is used with success for disinfecting certain inflamed mucous membranes. Boric acid is little used in solution, but as a dry powder is widely employed for dressing wounds after operation. Its irritant properties are slight, and being non-volatile its action is long continued. A saturated solution is of great value for operations on the eye, and for disinfecting the mucous membranes of the buccal and nasal cavities, the rectum, vagina, and bladder. Naphthol of a strength of 1 in 1000 is a feeble antiseptic. Naphthalin has the same properties as naphthol, exercises a stimu- lating action on the tissues, and promotes granulation of wounds. Camphorated naphthol is a yellowish-brown, syrupy liquid, produced by triturating one part of naphthol with two parts of camphor. Camphorated salol is an opalescent liquid, produced by warming together equal parts of salol and powdered camphor. Camphorated thymol is an almost limpid fluid, produced by triturating one part of thymol with two parts of camphor. These three products are used in treating suppurating wounds. Other valuable antiseptics are Lysol, Cofectant, Sanitas-bactox, Izal, and Creolin. ANTISEPSIS AND ASEPSIS IN PRACTICE. 75 Sterilised salt solution consists of boiled water containing 80 grains of pure chloride of sodium per pint, and is very useful in washing out the abdominal cavity during or after operation. The number of antiseptics increases every day, but the more recent have no marked superiority over those mentioned. Carbolic acid, corrosive sublimate, chloride of zinc, iodine and iodoform still maintain their position.. In selecting an antiseptic preference should be given to one that does not irritate the tissues, that does not readily poison, and that destroys all micro-organisms. Warm or hot solu- tions of antiseptics are always more efficient than cold. Disinfection of the Hands. Fiirbringer's experiments have shown how difficult it is to render the hands aseptic. The matter is, however, of the highest importance, as the operator's hands are not infrequently the means of infecting operation wounds, and the surgeon who desires to avoid after-complications will take especial care in this respect. The spaces beneath the nails, the folds of skin at their base, the folds of the skin itself, and the orifices of skin- glands are all refuges for microbes, to destroy which demands the most minute precaution. In some cases it is impossible to render the hands completely aseptic. Kummel and others have shown that after soiling with pus or with putrid or septic liquids from infected wounds or dead bodies, it is impossible to render the hands absolutely sterile for forty-eight hours. The surgeon should bear this in mind when arranging to perform laparotomy, ovariotomy, or cryptorchid castration. He should either defer operation for some days or redouble his precautions ; neglect in this respect explains failure where apparently all the conditions for success have been present. The nails should first be cut short, and all foreign material mechanically removed from under and around them. The hands and forearms should next be washed for some minutes with soap and warm water, and scrubbed thoroughly with a brush or a Turkish flesh glove. They are then washed with rectified spirit, and lastly with 1 in 1000 solution of sublimate. The alcohol dissolves fatty materials which would otherwise impede the action of the antiseptic, and enables the latter to penetrate some distance into skin ducts, etc. More complex methods have been suggested, but the above is sufficient. In veterinary surgery the precautions usually taken extend only to thoroughly cleansing nails, washing the hands with hot water and soap, and thoroughly rubbing them with 1 in 1000 sublimate solution or 5 per cent, solution of carbolic acid. The hands must be rendered aseptic and kept aseptic throughout the operation. For this reason the operator should 76 DISINFECTION OF INSTRUMENTS. avoid touching the skin surrounding the point of operation, the table, the straw or any object which has not been disinfected. Even when nothing suspicious has been touched, it is well during operation to rinse the hands from time to time in a disinfectant ; should the hands actually have been soiled, they must immediately be cleansed again. Disinfection of Instruments. The handles of modern instruments are generally made of German silver, nickel, or aluminium. They should present no unnecessary ornamentation, depressions, grooves, corrugations, or spots likely to hold dirt. Instruments like scissors, forceps, etc., should be capable of disarticulation for cleansing purposes, and complicated instruments difficult to clean should be discarded. Wherever possible instruments should be in one piece, like the retractors in Figs. 77, 78, and 79 ; for more complicated instruments the French joint, as shown in the lion forceps, Figs. 80 and 81, is the best. For sutures, Largu's or Mooij's needles are preferable to others, being simple and readily sterilised. For syringes with pistons one can often substitute a simple glass tube carrying a rubber ball, the piston being then replaced by a column of air. Many methods and materials for rendering instruments aseptic have been recommended. Immersing the instruments for a minute in pure carbolic acid and afterwards rinsing them in a 5 per cent, carbolic solution is advised by many surgeons. Boiling in water is a simple and practical method ; and any detrimental effect on the blades can be prevented by adding one per cent, of sodium carbonate. Where a higher temperature of 250° to 260° F. is required the bath may be of oil or glycerine. The vessel in which this boiling takes place should be provided with a tight lid, so that after boiling the whole may be placed on one side to cool. Immediately before operation the instruments are removed from it, and placed in trays containing an antiseptic solution (3 per cent, carbolic), in which they remain until required for use. Should the operator have finished with an instrument for the moment it should be rinsed in a separate vessel and then returned to the solution, and never allowed to come in contact with the straw or be laid on the animal's body. Trays of glass or porcelain are very useful, though vulcanite is also largely employed, being much less brittle. All vessels of the kind must be subjected to a thorough cleansing before use. As instruments with wooden handles are damaged by boiling, they should be disinfected by cleansing and prolonged immersion in five per cent, carbolic solution. They should not be used in aseptic surgery. DISINFECTION OP INSTRUMENTS. Ti Autoclaves, steamers, or stoves are only used in the laboratory or in hospital practice. Disinfection with burning alcohol is another rapid method of disinfecting instruments. The instruments are placed on a metallic Fig. 69 Fig. 71. Fig. 72. Fig. 68 Fig. 67. II Figs. 67-72. —Scalpels plate previously rinsed with a little alcohol, which is then ignited. A few minutes suffice to render them sterile, when they can be placed in a weak antiseptic solution or in boiled water. Although Fig. 73. — Dissecting forceps. excellent for ecraseurs, forceps, directors, etc., this method is apt to damage the temper of bistouries, scalpels, and scissors. Gum-elastic probes are washed in strong alcohol and afterwards in 1 per 1000 sublimate solution. In addition to instruments the surgeon employs sponges, tampons 78 ASEPTIC DRESSINGS. of cotton or tow, compresses, suture threads, and various dressing materials. All such materials should previously have been rendered aseptic. After having been used, sponges are washed in running water, placed for ten to twelve hours in a 1 in 1000 solution of permanganate of potash, washed in boiled water, and afterwards placed in strong carbolic solution, where they should remain for at least two to three weeks. Immediately before use they are washed Fig. 75. — Curved scissors with French aseptic joint. Fig. 76. — Straight scissors with French aseptic joint. in boiled water, to remove the excess of carbolic with which they are saturated. For some time sponges have given place to compresses of gauze or sponge tissue sterilised in the autoclave, and tampons of absorbent wool. Many veterinary surgeons still use tow. This is unsuitable unless it has been thoroughly cleansed and sterilised by heat or by immersion in a boiling antiseptic solution. When used the method generally adopted is to plunge the tow for five minutes into boiling water or into a boiling soda solution. Silk thread is sterilised by immersion for half an hour in boiling STERILISATION OF SUTURE MATERIAL, ETC. 79 water, or by exposure to a temperature of 220° to 230° F. in the autoclave. Immersion for a quarter of an hour in strong carbolic solution is also sufficient. It is preserved in glass holders (see Figs. 84—87) in 5 per cent, carbolic solution, or in 1 in 1000 sublimate solution. Catgut is deprived of adherent fat by immersion in ether, and after drying is wound on bobbins. These can be sterilised by dry Figs. 80, 81.— Lion forceps, with French aseptic joint for cleansing and sterilising. heat, and preserved in a strong sublimate or carbolic solution in alcohol or in boiled olive oil. Silkworm gut is treated with ether, boiled for half an hour in water, and then placed in tubes containing 2 per 1000 solution of sublimate. Paraffined thread is prepared by immersing hemp thread, previously saturated with ether or oil of turpentine, in melted paraffin. To remove any stiffness it may be passed through a cloth before use. This thread is flexible, nearly impervious to organic liquids, and does not cut out rapidly. It is, therefore, especially useful for sutures intended to remain long in position. Chinese twist, chromicized gut, tendon, horse hair, silver wire, Fig. 77. Fig. 78. Fig. 79. Retractors with metal handles for aseptic surgery. 80 ASEPTIC SUTURE MATERIALS. Fig. 82.— Steal steriliser for instruments (packed for transport). and other suture materials may be obtained ready for use from the instrument makers. Drainage-tubes are preferably made of red rubber. After thorough washing in con- centrated permanganate of potash solution they are left for twenty minutes in boiling water, trans- ferred to tubes containing 2 per 1000 solution of sublimate, and finally sterilised by exposure to a temperature of 120° for half an hour. They are sometimes replaced by bundles of aseptic silk or catgut, along which drainage proceeds, or by slips of gauze. The field of operation and surrounding parts must be most carefully cleansed. In all animals the skin is covered with extremely numerous and varied micro-organisms, among which staphylococci are particularly abundant . It is, therefore, always im- portant to disinfect* the parts. If the skin is healthy, the hair is re- moved with scissors or a clipping machine, the parts thoroughly soaped, shaved, scrubbed, and washed with boiled water. After being dried with a sterilised compress, the parts are rubbed with alcohol or ether to remove fatty materials from the surface, and are finally washed with iodine dissolved in chloroform, strong carbolic, 1 in 1000 sublimate solution, or douched with tincture of iodine. If the skin is infected or the seat of an ulcer, suppurating wound, or fistula, it is necessary, the day before operating, or even some days in advance, to curette the wound, afterwards proceeding as just indicated. In abdominal operations, exposing the peritoneum, special care must Fig. 83. -Steam steriliser for instruments (open in use). DISINFECTION OF THE AREA OF OPERATION. SI Fig. 84.— Silk-holder for hospital use. be taken to shave and disinfect a large surface, while the operative area should be covered with towels recently boiled or soaked in an effective disinfectant. Convenient irrigators for holding the above disinfectant solutions are shown in Figs. 89 and 90. These two principal methods, however, are not applicable to all surfaces. They may require modification in certain regions. In all mucous membranes it. is necessary to remove the mucus from the surface by freely washing with boiled water in order to permit antiseptic solutions to act more intimately. The mouth is always in- fected with micro-organisms, and is difficult to disinfect. In large animals disinfection is confined to washing freely with water followed by 2 to 4 per cent, solution of boric acid, 1 in 1000 of permangan- ate of potash, or 1 per cent. of chloral hydrate. In the dog decayed teeth should be removed, and, if necessary, the gums swabbed with tincture of iodine or solution of hydrogen peroxide. To promote intestinal antisepsis previous to intra-peritoneal operation, the bowel should be emptied by a purgative, the animal placed on a reduced diet, while antiseptic substances can be administered by the mouth. Saline purga- tives in small repeated doses are valuable as a preparation, after which naphthol, or salol may be given in the proportions of five to fifteen grains for small animals, and one and a half to six drachms for the horse and ox. Rectal injections of a solution of 1 in 1000 permanganate of potash, 1 to 2000 sublimate, or 4 per cent, boric acid, complete the preparation. When, during operation, the bowel is divided, the ends with- drawn from the peritoneal cavity are kept closed by clamps or by pressure with warm sterilised compresses, care being taken to avoid soiling the peritoneum by material escaping from the incision ; the bowel must not be returned, until it is certain that the wound has Fir;. 85.— Portable silk-holdor. 82 DISINFECTION PRIOR TO OPERATION. been completely closed and the serous coats around the suture touched with a strong carbolic solution in order to produce a slight adhesive inflammation. For eight to ten days after operation only small quantities of liquid nourishment, such as milk and beef -tea for small animals and hay-tea for others, should be given. Ordinary food is then gradually resumed. In disinfecting the rectum, the food is diminished for several days in advance, and the same materials are pre- scribed as for intestinal antisepsis. In addition, how- ever, the rectum must be frequently irrigated. The anus is disinfected in pre- cisely the same way as the healthy skin. The nasal cavities can with sterilised lukewarm water. of sublimate or 86. — Sterilised silk in portable tubes. sealed be rendered aseptic by washing out and afterwards by injecting a 1 in 5000 solution a 1 in 1000 solution of permanganate of potash. The eye demands special precautions. It can be bathed with normal saline solution, 4 per cent, boric solution, or the following solution of biniodide of mercury recommended for man by Panas : Biniodide of mercury . . . 5 to 10 centigrammes. Absolute alcohol . . .20 grammes. Boiled filtered water . . . 1000 grammes. Fig. 87. — Showing method of withdrawing silk. Sublimate must also be greatly diluted (1 in 5000). The instru- ments must be perfectly sterilised, especially if the globe of the eye is to be opened. Disinfection of the external auditory meatus is carried out with DISINFECTION OF THE AREA OF OPERATION. S3 weak antiseptic solutions. The lining is cleansed with warm water and soap, dried, and irrigated with 3 to 4 per cent, boric acid solution, 1 in 1000 permanganate of potash, or 1 in 5000 sublimate solution. If discharge is abundant, the use of bismuth, salol, or iodoform is indicated. Antisepsis of the vagina is usually easy. Soap solution is used for cleansing the mucous membrane, which is afterwards irrigated with 4 per cent, boric, 2 per cent, protargol, or 1 in 2000 sublimate solution. These irrigations are repeated on several successive days. Instead of syringes, irrigators consisting of a glass reservoir and an india-rubber tube can be used. It is diffi- cult, however, to disinfect the vagina when the mucous membrane is the seat of polypi, ulcer- ating tumours, or when it has been infected during removal of a putrid foetus. The uterus, after preliminary dilatation of the cervix, can be disinfected in the same way as the vagina, a long india-rubber tube being employed. Beyond passing the catheter, operations on the bladder are seldom required. Before operating for calculus in horse or dog, a course of urinary dis- infectants should be prescribed (salol, benzoic acid). In this case preventive treatment is of the greatest importance. Until now the dangers of catheterisa- tion, as usually practised, have not received sufficient attention. Acute cystitis and its various complications may follow the introduction of soiled catheters, which are cleansed with difficulty and Fig. 88.— Drainage are more or less septic. Catheters and bougies tubes in sublimate . ° . or carbolic solution, should be disinfected by prolonged immersion in strong antiseptic solution, and afterwards enclosed in gauze and kept in a special case. In operations on the foot, local antisepsis is ensured by the following method : — -The shoe is removed, the plantar surface of the hoof thinned, the hair clipped away from the limb up to the knee, the hoof thoroughly brushed with hot water and soap, freely washed with an antiseptic solution, in which it should be immersed for a quarter of an hour to twenty minutes, then enveloped in compresses saturated with an antiseptic, and fixed in position by means of bandages. Linseed poultices prepared with a strong disinfectant solution certainly soften the horn, and may be useful, 84 DISIM-'KCTION AFTER OPERATION. but from the point of vievi of antisepsis the superiority of compresses cannot be gainsaid. In all operations to obtain primary union, the wound must be scrupulously guarded against infection. All bleeding must be stopped, and the tissues brought exactly into apposition. A thin layer of blood in an aseptic condition between the lips of the wound does not prevent primary union ; the tissues tolerate it, and it is even serviceable in the process of repair ; but large clots are harmful and present a very favourable soil for the growth of pathogenic microbes. The bleeding surfaces are dried as far as possible, covered with antiseptic vaseline [vaseline 50, powdered boric acid 5, iodo- form 1], closely approximated throughout their extent, i.e. both superficially and deeply, and every effort made to secure contact. When coapta- tion is not perfect in the depth of the wound, a space is left for the accumulation of blood and serosity, in which any retained germs multiply rapidly. Where the wound implicates several different layers, it may be necessary, in order to keep these closely in apposition, to pass a number of deep sutures of catgut or silk fixed at their extremities to little rolls of gauze [deep or anti- tension sutures], in addition to inserting superficial sutures of silk or silk-worm gut. Lastly, the surface is washed with sublimate solution, dried with tampons of absorbent wool, and covered with a film of iodoform collodion, or with a dressing of surgical wool. When it is impossible to bring the surfaces of the wound perfectly together, or when there has -Irrigator Deen much loss of substance, provision must be for h hanSng US on made to P re vent the accumulation of discharges by wall. inserting one or more rubber drainage-tubes, a strand of plaited catgut ligatures, or a strip of gauze. Rubber drainage-tubes are generally employed. They should reach the depth of the wound, and as they tend to spring out, they should be fixed to the lips of the wound by a silk or other suture. Their presence allows antiseptic injections to be made into the bottom of the wound without touching the sutures. When the wound is redressed the tube must be Fig. 89. DRESSING OF OPERATION WOUNDS. 85 removed, disinfected, shortened if necessary, and replaced. Its outlet should be level with the wound edges and not compressed in any way. The seat of operation is protected by a " dressing " formed of layers of surgical wadding or tow, suitably arranged and fixed in position by bandages (see " Bandaging and Dressing "). Dressings applied to the upper regions of a limb should either be com- paratively loose or should extend to all the parts below, in order to avoid interference with circulation and such consequences as swelling and sloughing. The first dressing is exceedingly important. Very often it determines the entire after- course of the wound. It can be left in place for a varying time. If the patient's general condition is good, and the fever is slight, and if the dressing remains dry, it need not be renewed for twelve to fifteen days in winter, and from eight to ten days in summer. If, during removal, the deep layers of wadding adhere to the skin, they should be moistened and softened with a warm anti- septic solution, or in the case of the foot by placing the extremity in a bucket con- taining the liquid. The skin should be carefully cleansed with tampons of cotton wool. Where primary union has occurred the wound is found cicatrised on removal of the first dressing : if, however, it is only progressing favourably, nothing more is needed than the application of a fresh dressing, the same precautions being observed as on the first occasion. Care must be taken to avoid disturbing the wound or moving the lips ; drainage-tubes can be replaced after disinfection, fresh ones of similar calibre but of shorter length can be substituted, or drainage-tubes may altogether be discontinued. When the wound is suppurating the sutures must be cut, the drainage-tubes removed, and the whole cavity freely washed out, avoiding injury to granu- Fig. 90. — Portable irrigator. 86 DRESSING OF ACCIDENTAL WOUNDS. lating surfaces. A new dressing, with or without drainage, may be applied, or the wound may be left open and treated with anti- septic liquids or powders. The latter absorb wound discharges, check the growth of germs on the surface, and diminish the absorption of toxic products. The above are the measures required absolutely to prevent infection of operative wounds. Minutiae and superfluous details have been omitted. The Veterinary Schools of Europe contain operating theatres provided with installations and appliances for facilitating the practice of aseptic and antiseptic surgery. But it is not indispensable rigorously to follow in every case the technique, which has been indicated, to obtain good results. Without a large array of instru- ments, vessels, antiseptics, and dressing materials, asepsis in many operations can be nearly assured. Degive, who performed a series of one hundred castrations of cryptorchids without a single casualty, certainly did not conform in every respect to the rules of asepsis. Moreover many operations must be performed on the spot, and with the means at hand, if the patient is to be saved. The treatment of incised, lacerated, punctured, and other acci- dental wounds is very similar to that required for operation wounds. Some wounds, particularly those of the upper parts of the limbs where bandages cannot be secured in position, may be treated by the open method and frequently dressed with antiseptic lotions or powders. Arterial bleeding usually demands immediate attention, and it should be arrested without delay. In some penetrating wounds the injured artery may be difficult to find, and in that event the wound may be stuffed with a styptic tampon of gauze or cotton wool and sutured. To remove foreign bodies and infective materials, and to promote early healing, accidental wounds must be thoroughly cleansed and disinfected. Where infection is feared or in doubt the wound should be swabbed or scrubbed and afterwards flushed with a warm solution of hydrogen peroxide, or tincture of iodine. Before closing the wound the necessity of providing drainage should be considered. Many accidental wounds are so situated as to drain naturally, provided a small opening is left at the most dependent point. Efficient drainage is most important in the treatment of punctured wounds, which frequently are infected by the wounding instrument. In many cases a counter-opening will be found to furnish the best outlet for discharge ; or the puncture may be enlarged, its track carefully disinfected, a drain inserted, and the whole wound covered with an absorbent dressing. In all accidental DIVISION OF TISSUES. 87 wounds movement of the injured part should be prevented as far as possible by splints and supporting bandages, and, in horses, by- slinging. In routine practice, preference should be given to such methods of treatment as are simple, effective, and relatively cheap, but expense should be regarded as of secondary importance when dealing with penetrating wounds of the thorax, abdomen, joints, tendon sheaths, and with injuries to tendons, ligaments, and bones. It then becomes the duty of the practitioner to prevent, by every means in his power, the grave infectious complications which frequently result from such wounds. The unfavourable conditions under which he habitually works, render primary union of wounds in the greater number of cases uncertain. But, when unable to satisfy all the demands of the antiseptic system, he should at least observe its broad principles. V.— DIVISION OF TISSUES. Cutting and Puncturing Instruments. The first method of dividing soft tissues is by means of cutting instruments, as knives or scissors. Knives are of varying form and size : those in which the blade and handle are immovable are termed scalpels ; those in which the blade is protected with scales and turns on a hinge, bistouries. Knives, again, may be divided into sharp-pointed and guarded or probe-pointed ; either of these may be straight, convex, or concave. Scissors are either sharp or round-pointed, and flat or curved in the blades (see Figs. 74, 75 and 76). In making primary incisions a knife with a convex cutting edge is usually employed, and is grasped after the manner of a table knife (Fig. 91). In making long incisions the knife is held like a violin bow (Figs. 92, 93). For finer dissection the knife is employed after the manner of a pen (Fig. 94). In dividing tissues from within outwards the knife is grasped in a similar way, but the cutting edge is now directed upwards (Figs. 95, 96, and 97). Incisions are made by a light, drawing movement of the whole hand, usually from left to right, seldom in the opposite direction. The parts to be divided should be rendered tense by placing the thumb of the left hand on one side and the index ringer on the other side of the line of incision, and employing gentle traction (Fig. 98). 88 HOLDING [NSTRUMBNTS. When importanl vessels lie immediately beneath the point of incision it is sometimes convenient to raise the skin in a fold (Fig. 100). When considerable force is required in making an incision the thumb Fig. Of). Fig. 96. may be firmly applied to the skin, and the knife guided by the other fingers (Fig. 105) ; this prevents deviation from the straight line. In dividing very hard tissues, like horn and cartilage, the knife is grasped with the whole hand (Fig. 106). Incisions should be made rapidly and, if possible, of the prede- termined length at one stroke. Too short an incision impedes the deeper stages of the dissection, and is no advantage, for the linear cicatrix which may remain is of even less importance in animals Fig. 98. METHODS OF D1V1D1NO TISSUKS. 89 than in man. Moreover, the irregularity of the incision produced by a series of cuts greatly militates against rapid healing. Scissors are held as shown in Fig. 107, the thumb and third finger in the rings, the index finger on the joint. In dividing soft tissues the knife is either guided by a director or by the finger (Figs. 108 and 109). In the former case the director, S*£s§r^ Fig. 99. lightly held between the thumb and index finger, is introduced into an already existing opening in the tissues, a convex or pointed knife is slipped into the channel and steadily thrust forward with a lifting movement, so that at the end of the stroke it is nearly at right angles to the long axis of the director. In some cases it may be necessary to make the stroke towards the operator (Fig. 110). Fig. 100. Where important organs might be endangered the operator grasps with forceps and raises a portion of the tissue to be divided, the neighbouring portion being similarly raised by an assistant, and the parts divided between the two forceps. The forceps are then reapplied and the dissection so continued. 90 METHODS OF DIVIDING TISSUES. For holding the edges of wounds apart sharp hooks or retractors are employed (Figs. 77 to 79). When operating in certain cases other methods of dividing tissues are sometimes resorted to, such as tearing, blunt dissection, linear crushing by the ecraseur, the use of the elastic ligature, and the cautery. Tearing is chiefly used in removing sharply defined tumours which are only slightly adherent to neighbouring tissues. The skin having been incised the growth is isolated by pushing aside or tearing through the surrounding tissues with the fingers, or by a combination of these methods. Although valuable on account of not endangering important vessels or nerve trunks, this method gives very acute pain where the parts are richly supplied with nerves, and is inapplic- able to such new growths as spread by the lymphatics, inasmuch as extirpation is incomplete and secondary tumours soon grow. When larger tracts of tissue are in question the fingers of both hands may be employed. Although wounds so made are really torn wounds, they bleed relatively little, and often heal very rapidly. Fig. 101.— Director. For blunt dissection the end of a director or a small spatula may be used. The movement is of a stabbing or thrusting character, the point tearing through the connective tissue and isolating the part without danger of haemorrhage. This method is excellent when operating in dangerous regions. It is particularly useful for isolating vessels, as in ligaturing the jugular vein or carotid artery. The wounds produced by blunt dissection heal almost as quickly as those made with the knife. The Ecraseur. The ecraseur (Figs. 102 to 104), is still much employed in veterinary practice. It crushes soft tissues, though to some extent it also acts like a saw. Mucous membranes, connective and fibrous tissues, muscles, vessels, neoplasms, are all cut without haemorrhage if the instrument is worked sufficiently slowly. Its action is especially remarkable in vessels : the middle and internal coats rupture and retract whilst the external coat is stretched and twisted in such a way as to effect almost complete closure. Pain, which is very severe as compression begins, diminishes with com- mencing section. As a rule the surface of section cicatrises less THE ECRASEUE, 01 Fig. 102. — Chassaignac's ecraseur. Fig. 103.— Chassaignac's ecraseur dismounted, showing rack. 92 DIVIDING TISSUES WITH THE ECRASEUR. rapidly than that made by the knife, owing to superficial cell necrosis. The ecraseur consists of an articulated steel chain, the loop of which is passed around the part to be divided and drawn tight until the tissue is finally crushed through. Chassaignac's ecraseur (Figs. 102 and 103) acts by means of the two rods H H\ which are provided with teeth controlled by the two spring pawls B B. By slightly depressing the handle G G on either side, one of these rods is drawn forward a tooth and immediately secured by its corre- sponding pawl, when it becomes the fixed point through the medium of which the opposite rod is drawn downwards. The lower ends of the two rods thus act alternately as fixed points on which the handle G G swings. Reference to the figures will show that move- ment of this handle in the method described will cause the rods gradually to descend, drawing the loop of the ecraseur K within the tube C, and slowly dividing any tissue enclosed within the loop K. In later ecraseurs, such as Fig. 104 the movement is effected g^Z2 FREE LOCKED #=€®lfe Fig. 104. — Professor Dewar's ecraseur. by a screw. At Professor Dewar's request Messrs. Arnold have produced an ecraseur with a particularly neat and effective catch by means of which the screw can be thrown into and out of action very readily. When the catch is in the position marked " free " the " slack " of the chain can be taken up so that the instrument is ready to commence cutting as soon as put in operation. By slipping back the catch the chain becomes locked to the screw, and the apparatus is ready for use. The screw movement is certainly preferable to the rack originally fitted in the Chassaignac instrument. This instrument is now made long enough for the castration of mares and cows, and as the chain is bevelled on one edge it crushes through instead of cutting the tissues, thus avoiding a frequent cause of post-operative haemorrhage. On the other hand it may be reversed it very fibrous tissues require to be divided. Small and even medium-sized vessels may be divided in this way without bleeding. The action depends to some extent on the rapidity ELASTIC AND OTHER LIGATURES. 93 with which the process is carried out. The slower the movement the less the bleeding. For this reason very vascular tissues should be very slowly divided, and pauses should occasionally be made ; Fig. 105. FlG> 106 . between each complete movement of the handles, or each rotation of the screw, fifteen to thirty seconds may be allowed to elapse. Fir,. 107. Fig. 108. Specially thick tissues may be divided in two portions, the centre being perforated, and the chain applied alternately to either side. Fig. 109. Fig. 110. Ligatures. Soft tissues may be divided by passing around them thin tightly-stretched cord. Linear necrosis continues at the point 94 ELASTIC LIGATURES. of ligation until the cord becomes slack, but inasmuch as many materials like reindeer sinew or metallic ligatures are comparatively inelastic, the ligature may after a time require to be reapplied, and large masses cannot be dealt with by a single ligature, but require several. The Elastic Ligature is exceedingly useful. Being applied in a tensely stretched condition it "follows up " the parts as they yield. Vulcanised rubber cord or tubing, of a thickness proportionate to the mass to be divided, is used. An assistant holds one end of the cord while the operator grasps and stretches the other, passing it three or four times around the pedicle of the growth. The two ends are held in a crossed position by an assistant, when they can be tied together with an ordinary thread. After being firmly tied the ends are released, and as they imme- diately return to their previous volume they so greatly exceed the Fin. 111. — Diagram showing elastic ligature applied. Fig. 112. — Diagram to show extent to which contraction proceeds. area of the knot as to render impossible any chance of retraction. Fig. Ill shows a ligature applied to a rod, and Fig. 112, the same ligature removed, to exhibit the degree to which it finally contracts. Solid rubber cords are better than rubber tubes, which are apt to break when tied. In removing tumours with well-defined pedicles the elastic band is easily applied, but when the tumour is more or less sessile it is necessary to transfix it with one or two long needles crossed at right- angles to prevent the ligature slipping off. The surfaces left by the elastic ligature granulate readily. This method is especially useful in ligaturing very vascular tissues because vessels are securely closed before division occurs. Cagny recommended the elastic ligature for docking. The most painful part of this operation is not the division of the tissues, but their cauterisation, and in certain high-bred animals the application GALVANIC AND THERMOCAUTERIES. 95 of the iron causes violent struggling. Cauterisation can be dispensed with by applying before section an elastic bandage to the tail just above the point of division. It has been suggested that the bandage should be left in position for a week, but this would be dangerous, and it is sufficient to leave it twelve to twenty-four hours. The Galvanic and Thermo-cauteries. In the galvanic cautery a loop of platinum wire is passed around the tissue to be divided, and after being raised to a bright red heat by the passage of an electric current, is gradually drawn tight. On account of its com- plexity and expense, however, this instrument is very seldom used in veterinary surgery, especially as Paquelin's thermo-cautery (Figs. 113, 114) renders almost equally good service and is much cheaper. The thermo-cautery consists of a hollow platinum terminal which may be of varying shape. After being heated in a spirit flame it is kept at a bright red heat by injecting a mixture of ether or benzine vapour and air into the head. Tissues divided by this instrument bleed very little, though the scab produced by the cautery must have a certain thickness, to attain which the division must be made deliberately. The wounds produced heal comparatively slowly. (For other cauteries, see pp. 155-160). Puncture. A puncture is an incision of considerable depth but of comparatively small diameter. Puncture to permit fluids or gases to escape from cavities, like the thorax, abdomen, or bowel, is termed paracentesis. To prevent the entrance of air into deeper seated tissues or into the cavity to be opened, the skin is often drawn to one side before operation, so that returning afterwards to its ordinary position it closes the deeper opening. Subcutaneous puncture may also be practised by first introducing the perforating instrument horizontally a short distance under the skin, and, after altering its direction, making the desired puncture ; the walls of the opening immediately collapse on the removal of the instrument. An ordinary pointed knife, bistoury, scalpel or lancet may be used for puncturing. The knife is held like a pen, the thumb on one, the index and middle finger on the other side, the little finger being used as a support. The point is caused to enter vertically by extending the previously bent fingers. In withdrawing the instru- ment the opening may, if necessary, be enlarged (Figs. 120, 121). In using a bistoury or lancet the handle is held at right angles to the blade. Many persons grasp the blade, only leaving uncovered sufficient to penetrate to the desired depth ; but this method, however, has the disadvantage that in case of a mistake in regard to the thickness of the tissues to be divided the fingers must be moved, 96 THKi:M<>-< AI'TKUIKS. Fig. 113. — Paquelin's cautery in box. Fig. 115. Fig. 114.— Paquelin's cautery in action. Fig. 110. Fig. 117. SURGICAL PUNCTURE, S7 moreover the operator runs considerable risk of wounding himself. The surgeon should possess sufficient delicacy of touch to know when opposition ceases, that is when the cavity is entered. Supporting the instrument with the ringers in the method described assists in this respect. Other puncturing instruments are exploring needles and trocars. The trocar consists of a pointed steel rod provided with a metal shield or tube, exactly corresponding with it in other respects but a trifle shorter. The rod may be of varying length and thickness, straight or curved, cylindrical or oval. The point is usually triangular in section. At the lower end of the cannula, where it abuts on the handle, are two holes or rings to permit of its being fixed into position by tapes. As a rule the upper end of the cannula discloses two short slits, which permit the parts to spring slightly Fig. 122. Fig. 120. Fig. 121. and apply themselves closely to a trifling circular depression formed just behind the point of the trocar. This device causes the instru- ment to enter much more easily, as the union of the trocar and the cannula then presents no projection. The handle of the trocar is grasped in the hollow of the hand, the fingers and thumb steady the stem, and in use the instrument is thrust into the cavity to be penetrated with a single rapid movement. The cannula is then fixed with the left hand and the stilette or trocar removed with the right. While withdrawing the cannula the trocar should be reinserted, and the skin in the neighbourhood of the puncture should be pressed down with the thumb and index finger of the left hand to prevent it being lifted. Division of Hard Tissues. The horn of the hoof is divided with a special knife grasped with the whole hand, Fig. 106. Bones are divided with drills, chisels, saws, and forceps. The bone is prepared 98 TROCARS. for sawing by removing the periosteum with a periosteotomy or a chisel or gouge, Figs. 126-7. Files and rasps are sometimes used to remove sharp edges or projecting points from sawn surfaces. In this connection, the sharp spoon or curette, Figs. 128-130, used for scraping diseased bones and cartilages, unhealthy granulations, callous walls of sinuses, etc., deserves mention. It is not sufficiently valued in veterinary surgery. It consists, as the name indicates, of a small steel spoon with a sharp edge attached to a stem or handle. The Fig. 123.— Trocar for tapping the chest. Fig. 124.— Trocar for tapping boweJ. Fig. 125.— Trocar for puncture of rumen. most useful are the smaller because they can readily be passed into sinuses, in certain cases into bones, and into any hollow space. A selection of various sizes ought, however, to be kept. Curettes are sometimes formed with hollow handles, and an arrangement by which a stream of disinfecting fluid can be caused to flow from the bottom of the spoon, Fig. 130 ; the material loosened is washed DIVISION OP HARD TISSUES. 99 away by the stream of fluid. The curette is firmly grasped and used with considerable pressure. The sharp edge of the spoon quickly removes necrotic tissue whilst gliding over firmer healthy parts without seriously affecting them. Particular care must be taken to remove everything of a diseased nature, without which rapid healing need not be expected. The chisel and gouge, Figs. 126 and 127, are now seldom employed for dividing bones because of the danger of shattering the bone when using the mallet or hammer. They have largely been replaced by bone forceps, Fig. 131, which are made with blades either at right angles to the long axis of the forceps or parallel with it. Each form has special uses. Saws are of several forms. The frame saw (Fig. 132) consists of a blade, a frame, and a handle. The blade is made somewhat finer towards the back, so as to saw freely and not become fixed in the furrow. It is secured at one end by a screw for regulating the tension, and at the other carries a small rivet which prevents the blade slipping through the slot into which it is introduced. The frame is either quadrangular or semicircular. The handle was formerly provided with depressions to fit the fingers. As, however, this rendered it difficult to clean, modern saws are provided with plain curved handles. Fig. 126. Fig. 127. A Fig. 128.— Curette. Fig. 129.— Curette. Fig. 130.— Flushing Curette. The nature of chain saws is almost sufficiently indicated by their name. They consist of a number of articulated links, carrying on one side saw teeth (Fig. 133). On account of their cost, however, they are not much used in veterinary surgery. The end of the chain 100 BONE SAWS AND FORCEPS. is passed around the bone by means of the needle and thread shown, and is then attached to the handle ; by drawing the chain to and Fig. 131. — Bone forceps. fro the bone is gradually sawn through. A trephine (Fig. 309) consists of a hollow steel cylinder bearing teeth on its free border. Fig. 132. — Frame saw for bone. A central terminal steel point is usually added to steady the trephine in position, and by rotating the handle alternately towards the Fig. 133.— Chain saw. right and left a circular piece of bone is gradually cut through. Trephines are used for opening the facial sinuses, the wall of the hoof, and the cranial roof. METHODS OF UNITING WOUNDS. J 01 VI METHODS OF UNITING WOUNDS. Five methods of wound healing are recognised, viz : (1) immediate union or primary adhesion ; (2) first intention or plastic adhesion ; (3) second intention or granulation ; (4) third intention or union of two opposed granulating surfaces ; (5) healing under a scab. Healing by primary adhesion seldom occurs except in small aseptic operation wounds. Healing by first intention or by adhesive inflammation occurs in aseptic incised wounds in which the edges have been main- tained in apposition and free from irritation. Lacerated, contused, punctured and open wounds heal by second intention, but owing to infection, the process is usually accompanied by pus formation. In healing under a scab, the protective may be formed of dried blood or exudate, or furnished by antiseptic adhesives (collodion, tannoform, iodoform and tannin), or by the carbonised tissues as in using the actual cautery after amputation of the horse's tail. Healing by first intention with the formation of a mere linear cicatrix is the surgeon's ideal, but can only be attained when the margins of the wound are accurately united and held steadily in position. Given these conditions, healing by plastic adhesion is assured in an aseptic wound. Apposition is best effected by sutures, i.e. by drawing together the edges of the wounds by stitches ; though some wounds may be united by the use of adhesives like collodion, wound gelatine (either alone or with the addition of oxide of zinc), sticking-plaster, pitch plaster, or strips of fabric fastened to neigh- bouring parts by glue. The wound is disinfected, the hair shaved from the neighbouring parts, the skin dried, and slender strips of plaster applied at right angles to the long axis of the wound. Once these firmly adhere, the edges of the wound are pressed firmly together, the free ends of the strips of plaster carried straight across with some tension, and fastened on the opposite side. Another method is to fix strips on either side alternately, and by drawing in opposite directions on opposing pairs to bring together the lips of the wound. A third method consists in fixing a somewhat broad strip of plaster along each edge of the wound and uniting the strips by sewing. Degive uses rubber bands to draw together the strips in place of sewing. In using collodion the edges of the wound are pressed together with the fingers, the collodion applied thickly, and the wound held until such time as the dressing has had time to dry. Strips of linen may also be saturated with collodion, and applied rapidly across the edges of the wound whilst the lips are pressed together. 102 BANDAGES. Ill veterinary practice, this method of uniting wounds can only be used in rare instances, partly because of the presence of hair, partly because of the animal's resistance and the violent contraction of its muscles, especially of its panniculus muscle. If plaster is applied, even in broad strips, over the hair it soon looses its hold, and the wound gapes or the continuous pull tears out the hair with a similar result. When the hair is shaved and the strips applied directly to the skin, they are apt to become detached by the rapidly growing new hair before firm union of the wound surfaces has taken place. Bandages, however, can be employed with greater success. In many positions, for example in the extremi- ties, union can be effected by using bandages without the help of sutures ; but the method is never thoroughly reliable, for which reason bandages are best utilised to reinforce or assist sutures, to neutralise excessive ten- sion and tearing out of the threads, or to check move- ment, and thus ensure the most favourable conditions for union. Formerly little attention was given to the proper use of sutures, and it was thought that in animals wounds seldom healed by primary intention, the reason being that operators took little pains to ensure antisepsis, and consequently the sutures rapidly tore out. Only fresh wounds were sutured, and old wounds were always " freshened " before being united. It is true that fresh wounds present the most favourable conditions for healing by first intention, but it is also possible to bring together granulating surfaces and effect healing. Furthermore, bruised or torn wounds were not sutured, though even Fig. 134. -Largu's suture needle ; metal handle for aseptic surgery. Fig. 135. De Mooij's suture needle all metal, for aseptic sur- gery. SUTURES. 103 Fig. 137. — Showing method of using needle-holder. they may heal by primary intention, provided the margins are not absolutely crushed, have not lost their vitality, and have not been cut off from the circulation. Tissues in which the circulation has been reduced to an absolute minimum may still retain their vitality by means of the " plasmatic " infiltration until circulation of blood by the formation of new blood-vessels becomes possible, and small fragments of dead tissue can be cast off without imperilling primary union. Deep wounds are often left open because of the danger of in- fection from retained discharges. By using drainage-tubes , h o w- ever, some of these may be united without bad consequences. On the other hand, great tension, especially in wounds with loss of substance, contra-indicates the use of sutures, which would rapidly cut out, and would therefore only be a drawback. Moreover, those portions of the lips of the wounds enclosed within the threads might themselves die, increasing the loss of substance. Lacerated wounds, especially when deep or very irregular, are sometimes left u n - sutured, but when muscles have been torn and the margins of the wound are not puckered or necrosed sutures should be inserted. In such wounds the sutures may not remain in position serve to promote union in a It is inadvisable to remove irregular fragments from the edges of a lacerated wound, because although the pared lips may more closely approximate to a straight line, sound tissue may be removed, the wound is enlarged, and the tension on the sutures must be increased. Sutures are therefore only contra-indicated when marked tension exists, or when the wound suppurates or is offensive. Almost all Needle-holder (Hagedorn's). for more than a few regular manner. days, but they 104 SUTURES. wounds iii animals are more or less infected, but by the free use of disinfectants such infection may be reduced to a minimum. For suturing wounds needles and various kinds of suture material are required. Needles are either simple or provided with a handle, and may be straight or curved ; some of the latter again being curved throughout, and representing the segment of a circle or ellipse, others half curved, only the anterior half being curved, the posterior being straight. The last two are the most useful. Some needles are curved in the plane of their great- est thickness in order to ensure greater stiffness. They are, however, less easily grasped and directed. In modern needles the point is almost always lancet-shaped and double cutting. Numerous com- plicated arrangements have been introduced to facili- tate threading, but have not met with general acceptance. One of the most practical is shown in Fig. 139. Compound or handle needles are fixed in a handle and carry the eye close behind the point (Fig. 134). They are passed through the edges of the tissue until the eye is exposed, and then threaded and withdrawn, bringing the thread with them. When using small or sharply curved needles, working in the depths of a wound or suturing firm tissues, a needle-holder (Figs. 136 to 138) is almost indispensable. In case of need a dressing-forceps efficiently replaces the special needle-holder. The chief suture materials are silk, silkworm gut, and catgut, none of which impedes healing. Catgut is very useful, as it becomes absorbed after a time, and therefore the stitches require no further attention ; but sometimes this occurs very rapidly, with Fig. 139. — Suture needles. INSERTING SUTURES. 105 the result of releasing still disunited portions of the wound and allowing the lips to open. To overcome this difficulty, chromicized catgut, which only softens very slowly, is employed, but silk is pre- ferable for all skin wounds, and can even be used for abdominal operations, as if properly sterilised it does not irritate and becomes encysted or disappears. A number of different sizes must be pro- vided of each of these materials. Silkworm gut is very smooth, non-absorbent, and non-irritant ; it is largely employed for suturing skin wounds where immediate union is of much importance. Soft metallic wire, kangaroo tendon, and prepared horsehair are also used. To preserve silk and catgut in an aseptic condition the special holders shown in Figs. 84 and 85 are very practical. General Directions for inserting Sutures. Before inserting sutures bleeding must have completely ceased. Capillary haemorrhage is sometimes stopped by the sutures themselves, the bleeding surfaces being pressed together ; but any large vessels should be ligatured or twisted, otherwise the object of suturing will be defeated. All foreign bodies, and not merely those of a macroscopic character like fragments of dirt from the wounding body, or of crushed tissues, clots of blood, etc., but also organisms which would set up inflam- mation and suppuration, must be removed. This can be effected by shaving the hair from around the wound and carefully disinfecting the parts. Wounds are in the most favourable condition for union when all bleeding has ceased and the surfaces are covered with a thin film of clear serum. Although in human surgery only sterilised, that is, aseptic, dressings and sterilised water are used, it is much better in animals to use some disinfectant, because in their case wounds are much oftener infected from the beginning, and have usually been inflicted a considerable time before coming under the surgeon's notice. The preceding measures having been carried out, the lips of the wound are approximated, and a decision arrived at as to the number, kind, and arrangement of the sutures to be used. The number, of course, depends on the size of the wound, and the kind on the tissue to be united — whether it be skin, bowel, muscle, etc. In wounds of the external ear with division of the conchal cartilage, and wounds of the eyelid involving the tarsal plate, the divided cartilage should be separately sutured and not included in the cutaneous sutures. The first suture is best inserted where the parts are most out of line. In very long wounds a series may first be placed at somewhat long intervals, so as to ensure the approximately correct apposition of the edges before proceeding to final closure. 106 SUTURING WOUNDS. Sutures must be so inserted as to bring the lips of the wound into close contact at all points, and it is better to err on the side of using too many than too few. In mucous membranes, bowel, etc., more sutures are necessary than in the case, say, of skin. Their distance apart ranges between three sixteenths and three eighths of an inch. The points of entrance and exit should be at equal distances from the borders of the wound, and in the case of the skin not less than three eighths of an inch. The old rule, however, that the needle should be inserted at a distance from the edge equal to the depth of the wound, so that the surfaces should touch throughout their extent and no open space remain below the suture, is not always to be followed ; one is sometimes obliged to seek primary union of the skin, leaving union of the depths to follow by granu- lation. A drainage-tube may then be inserted to facilitate discharge, care being taken to select the most dependent point for its exit ; but considerable doubt has been thrown on the efficacy of drainage- tubes, and after being replaced by gauze, plaited horsehair, etc., they have been finally abandoned by a good many operators. They are, however, useful in properly selected cases. Retention of dis- charge must be carefully prevented, because not only would such discharge prevent immediate contact of the deeper surfaces of the wound, but it would greatly favour the multiplication of micro- organisms. When rapid healing of deep wounds is of great importance, the deeper seated structures should be united with aseptic material, and the threads cut short before the skin wound is closed. These " buried sutures," if aseptic, cause neither irritation nor suppuration. In penetrating wounds involving the peritoneum the serous surfaces must first be brought together, then the muscles, and finally the skin ; similarly in extensive wounds of tendon sheaths and joints, the tendon sheath or capsule of the joint is first to be united and afterwards the skin. To avoid displacing the margins sutures should be inserted at right angles to the long axis of the wound. They should merely bring the surfaces into contact and hold them together ; the most frequent error in this respect is to draw them too tight, causing them to cut out or even to produce local necrosis of the lips of the wound. They should be left in position until the new tissue has become sufficiently firm. Primary union occurs within three to five days or not at all ; the changes in the wound after this time only influence the firmness of the cicatrix. The usual direction, to remove sutures between the fourth and sixth days, without reference to the size, SKIN SUTURES. 107 degree of tension, mobility, etc., of the wound, is apt to be followed by tearing apart of the newly formed, tender tissues within the succeeding twenty-four hours, necessitating a fresh operation. When sutures threaten to cut out, either from being drawn too tight or from local swelling, it is often advisable quickly to insert a few fresh ones rather more distant from the edges, so as to avoid the need for entirely resuturing the parts, which is not always successful. Sutures of aseptic material may be left in position eight to fourteen days or even longer without causing suppuration. Sutures may be divided into uniting or coaptative, which serve to draw wounds together, and tension sutures or satures of relaxation, which counteract the pull exercised by the tissues and thus relieve tension on the uniting sutures. The greater number of special sutures described from time to time have only an historical interest. Skin Sutures. The most important and the most commonly used is the plain interrupted suture shown in Fig. 140, which can be employed in almost all cases. It is made by passing a thread through the opposing lips of the wound, drawing the free ends together, and tying them firmly towards one side of the wound. The needle carrying the suture is grasped in the right hand, the thumb on the concave, the index and middle fingers on the convex side (Fig. 141), or a needle-holder may be used (Fig. 137). The edges of the wound are successively raised with forceps, and the needle passed through them first from without inwards, then through the opposite lip from within outwards (Fig. 141). Another method, however, is to raise both lips together, producing a somewhat deep fold, through the upper part of which the needle is passed with a single thrust (Fig. 142). This secures a larger surface for union ; when only the extreme edges of the skin are brought into contact, rapid union is much less certain. The comparative poverty of blood-vessels in the skin of animals as compared with that of man explains the difficulty with which skin surfaces alone unite, or when united hold together under tension. The appearance of a wound sutured in the above-described manner is certainly somewhat unsatisfactory, but there need be no fear of the fold remaining. As soon as the threads are absorbed or removed the fold disappears, leaving only a narrow cicatrix. To relieve tension in wounds so united it is generally desirable to insert one or more " relaxation " sutures. Sutures may be tied successively as inserted, or tying may be deferred until all are in place. In animals it is usually best to tie them as one proceeds. The fear of them tearing out when the 1U8 SUTUKKS. animal rises is unjustified, provided a sufficient uumber have been used and one or more "relaxation" or "tension" sutures have been inserted. Bayer always sutured wounds left after the removal of elbow tumours (eapped elbow), and although the sutures were exposed to great strain on the animal rising he never saw them tear out. In this country, of course, such tumours are not infrequently Fig. 140.— Interrupted suture. Fig. 141. — Inserting the suture. removed in the standing position under local anaesthesia, and the danger of tearing out is therefore comparatively trifling. The knots should lie to one side of the line of union, not on the wound. The threads are cut off short. When the lips of the wound are thin they often tend to turn inwards when sutured and to delay union. This cannot take place where a fold is raised, but should it occur it can easily be rectified by raising the edges with dissecting forceps and holding them in this position until the sutures are tied. In tying a surgical knot the free end of the thread is twisted twice around the fixed end when form- ing the first portion of the knot. To remove sutures the knots are grasped with forceps, the loops lifted sufficiently to allow the point of the scissors to be slipped gently beneath, and the threads cut and withdrawn. Should a thread stick, the lips of the wound may be supported with the free hand whilst the thread is being extracted. The continuous suture or glover's stitch (Fig. 143) is, after the interrupted (Fig. 140), probably that most commonly employed. It begins at one end of the wound like an ordinary interrupted suture. After tying the first suture the thread, however, is not cut off, but Fig. B 142.— Methods of suturing to secure largest possible surface Eor adhesion. K. Interrupted suture. D, D. Suture of relaxation. Vm AND OTHER SUTURES. 109 is carried obliquely across the lips of the wound and reinserted on the opposite side, the needle being passed once more at right angles through the edges of the wound, which must be held in close apposi- tion. In this way the thread passes continuously from one end of the wound to the other. At the point where it finally emerges it is cut off and tied at one side of the wound, so that the beginning and end resemble an ordinary interrupted suture. Another method consists in leaving the ends free until the suture is complete, when they can be knotted together, forming a long loop. In removing this suture the thread is divided at each loop, and the fragments withdrawn one by one. The glover's stitch has the advantage of being rapidly inserted, but many regard it with disfavour. Despite the greatest precautions the wound cannot always be maintained aseptic. If the glover's stitch has been used, and it should become necessary to relax or remove a thread here and there, the whole wound reopens. In the blanket or button-hole stitch (another form of continuous suture) the needle, after traversing the lips of the wound, is carried under the slack of the thread, so that the loop of each stitch as it is tightened is maintained at right angles to the edge of the wound, whilst the intermediate portion lies parallel to it. The pin suture, also known as the twisted or figure-of-8-suture (Fig. 144), though much praised by certain operators is less often used than formerly. It is employed where the edges of the skin are very thin and without much subcutaneous tissue, as, for example, in the eyelid, wing of the nostril, skin of the cheek, lip, etc., and where the margins show a tendency to roll inwards. The pin then acts as a support for the edges of the skin. The pins are usually from one and a half to two inches in length, and parallel sided. They should be flexible, and may be of brass, copper, silver, etc. Ordinary pins, however, are often used. They are sometimes inserted with a special instrument which holds the pin in a short tube provided with an awl-shaped handle ; or with the aid of a pin director or grooved needle. The pin-director is passed through the edges of the wound, and the pin having been inserted in the groove near the point is brought into position by withdrawing the director. Pins are passed at some distance from the edges of the wound, and a thread wound around the free ends in a figure-of-8. Where several pins are inserted in series one thread may be used for securing the whole, as in Fig. 144 ; in other cases a separate thread is employed for each. When secured the points of the pins are removed with cutting pliers. In removing pin sutures the margins of the wound 10 QUILL SUTURLS . should be pressed gently together with the fingers, when the threads can be cut and the pins removed. Threads glued to the skin by discharges may be left for a time in position. Another form of suture comparatively little employed is the so-called shoemaker's stitch. It is used in removing hernial sacs. new growths, etc. An awl-like needle carrying a long thread is passed through the new growth, and the loop is cut, leaving the growth transfixed with two threads. By tightly tying together the free ends of these threads on opposite sides the circulation in the peripheral portion of the growth is stopped, causing the part to become necrotic and fall away. By using a series of such sutures large growths may effectually be removed. Of tension sutures or sutures of relaxation there are several varieties. Ordinary interrupted sutures may be used for this purpose Fig. 143 — Continuous or glover's stitch. Fig. 144.— Figure-of-8 or pin suture. if more widely spaced and inserted further from the edges of the wound and to a greater depth than usual (see Fig. 145). To equalise and distribute pressure, thus preventing the stitches cutting through the skin, the suture shown in Fig. 146 is often used. It is formed by passing a number of double sutures through the lips of the wound in such a way that the loops lie on one side, the free ends on the other. A small cylinder of any kind, like a quill, or piece of cane, is then slipped through the loops ; the free ends are drawn tight and tied over a similar cylinder applied on the opposite side. The cylinders extend for some distance beyond the ends of the wound. It happens, however, at times that animals lie on the part so secured, and the cylinders are apt to cause pressure necrosis, making it necessary to remove the whole of the sutures despite their still being required. A modification was therefore introduced in which BOWEL STTTURES. Ill small rolls of gauze or tufts of cotton wool are employed for each complete suture, allowing one to be removed without disturbing the rest (Fig. 147). As, however, these become hard when saturated with blood or discharge, they may advantageously be replaced with small pieces of disinfected rubber tube, which can easily be cleaned, and which yield slightly when swelling occurs. In long wounds comparatively thick drainage-tubes may be used, sufficiently long to extend beyond the ends of the wound, thus reproducing the old form of suture shown in Fig. 146. This secures the advantages of greater cleanliness and a certain yielding quality, which permits of the longitudinal tube adapting itself to irregularities of surface, and thus exercising more regular pressure. Should a suture threaten to cut, the drainage-tube may be divided at any point, and the compound suture converted into interrupted sutures. M *$- f1 W -4* Fig. 145.— Ordinary deeply placed interrupted sutures used as sutures of relaxation. Fig. 146. — So-called "quilled" suture. Another form of tension suture is shown in Fig. 148. The free ends of the silver wire are passed through small oval plates of any light metal like aluminium, and secured by perforated shot slipped over the wire and compressed by pliers. Occasionally the plates are omitted, and small leaden shot, buttons, or glass beads alone used. The suture is then secured by forming a rather large knot above the bead at each end. Bowel Sutures. For uniting the walls of the bowel many com- plicated methods have been proposed, some of which certainly were of value in pre-aseptic days, but are now discarded. Possessing as we do suture materials which may safely be abandoned in the abdominal cavity without setting up suppuration, peritonitis, etc., many special precautions are now unnecessary. The sutures here- after described are those most frequently employed and easiest to use. In devising a bowel suture, it must be borne in mind that mucous membrane will not readily unite with mucous membrane 112 BOWEL SUTURES. on account of the' continuous secretion, and that the parts to bring together are the muscular and serous coats, the latter of which shows a great readiness to adhere and unite. Sutures must also ensure perfect closure of the bowel wound and absolutely prevent bowel contents exuding. They should, therefore, be inserted about every one eighth of an inch. On account of the thinness of the walls slender needles are necessary. Special fine curved needles or fine sewing needles can be employed. Aseptic silk is probably the best sewing material ; catgut is less adapted for the purpose, as it is sometimes too rapidly absorbed, the sutures yielding before the union of the surfaces has occurred. To prevent this, catgut rendered more resistant by the action of chromic acid has been intro- duced, but boiled silk has no such disadvantage and serves every purpose. .;£-:;', \* u UP Fig. 147. — Interrupted sutures combined J with sutures of relaxation. W_^ -H-. Fig. 148. — Tension position. The first and simplest form of suture was Jobert's. The needle was first passed through the serosa at some distance from the wound, penetrated the entire thickness of the bowel, and emerged close to the free border of the wound. The opposite lip of the wound was transfixed in a similar way. The ends were then knotted together and cut off (Fig. 149). This suture brought the serous coats into apposition, as shown in Fig. 150, but had the disadvantage that the threads passed through the lumen of the bowel, and might thus convey septic material from it into the peritoneal cavity, producing infection and inflammation in the track of the suture, resulting later in peritonitis. For this reason Jobert's suture was discarded in favour of Lem- bert's, in which the threads are passed in a similar way but do not penetrate the mucous membrane, only extending to the muscular or submucous coat (Fig. 151). bowel sutures. 113 Czemy reinforced Lembert's stitch by interrupted sutures uniting the mucous membrane, Lembert's stitch being employed to bring the serous surfaces into apposition ; he thus unites the edges of the wounds twice. The first series do not penetrate deeper than the submucous tissue. This system, however, is difficult to carry out. It is much easier if the suture begins and ends in the serous coat ; the knots then lie externally between the two surfaces of peritoneum. In isolated instances it may be desirable to unite the mucous Fig. 149. — Schema of Jobert' (now abandoned). suture Fig. 150.— Schema showing Jobert's suture in section. membrane itself. In such cases the first half or more of the incision should be sutured from within, and the knots tied on the inner surface. As, however, the wound becomes smaller this is no longer possible, and the remaining half of the wound must be united with sutures penetrating to the submucous coat but tied externally. The whole of the wound having thus been closed, the serous surfaces are brought Fig. 151. — Lembert's bowel stitch. 152 — Lembert-Czerny bowel stitch. together in the manner above indicated. It might be advisable in cases where other tissues lined with mucous membrane are divided, as for instance the eyelids, cheeks, salivary or urinary ducts, the oesophagus or bladder, to proceed as above, uniting mucous membrane to mucous membrane. The apposition of secreting surfaces should, however, be avoided. Artery sutures are very seldom required in veterinary practice, though small longitudinal wounds of arteries have been successfully 114 TENDON AND NERVE SUTURES* closed by inserting closely placed sutures of fine silk. In exceptional cases the continuity of a severed artery may be preserved by adopting Murphy's method of invaginating the central end within the peripheral end of the vessel and securing the parts with fine silk sutures. Tendon Sutures. In man recently ruptured tendons are united by deep catgut or reindeer tendon ligatures left in position. In such case the cut ends are drawn together by three or four strong sutures passed through the substance of the tendon, and the divided sheath, if not too much lacerated, is closed by fine catgut sutures. The external wound is then dressed and bandaged in the usual way. In one method the needle is inserted about a quarter of an inch from the cut end of the tendon, carried (say) downwards beneath the superficial layers of tendon fibres, brought out through the torn surface, and passed through the opposite end of the tendon after a similar but reversed fashion. The ends are knotted and cut off. If necessary, a complete ring of sutures may thus be inserted around the tendon, after which the outer wound is closed. It is often extremely difficult to insert sutures because the muscles retract the ends of the tendons to a considerable distance. The divided ends may, however, often be gradually approximated by inserting sutures, applying a dressing, and fixing the limb as far as possible with splints and plaster bandages. In small animals union of a ruptured tendon may be readily effected by sutures and by securing the limb in a position which will prevent undue tension of the sutured tendon. In cases associated with loss of tendon substance or where the space between the ends is too large to permit of their immediate appoximation, the gap is sometimes bridged by incising one end of the tendon to form a flap, which is attached to the other end by sutures. In horses and cattle ruptured flexor tendons are seldom sutured, but severed extensor tendons can be successfully treated by suturing and the application of splints or a plaster bandage to the limb. Nerve Sutures. In suturing divided nerves fine sewing needles are required. The edges of the cut nerve sheath are brought together by a number of closely placed stitches, and one or two sutures may be passed through the nerve trunk. Immediate contact of the cut ends is desirable, though not always possible without traction on the nerve. But even where the ends, after suturing, are separated by a space of half an inch, repair will follow and there need be little fear of permanent loss of function. As suppuration is the chief cause of imperfect repair of wounded nerves aseptic precautions should be scrupulously observed throughout the operation. HiEMOSTAStS. 115 VII.— METHODS OF PREVENTING OR CONTROLLING HEMORRHAGE— HJEMOSTASIS. The first check to the flow of blood from a divided vessel results from the contraction of the internal and middle coats and the mechanical closure of the bleeding orifice. The flow being checked a clot soon forms, which seals the aperture, partly by its contraction, partly by acting as a plug or cap. The slower the flow the more quickly does such a clot form. The cardiac weakness following on loss of large quantities of blood therefore favours cessation of bleeding. In incised wounds, the divided ends of the vessel retract into the tissue, which then closes over them and checks haemorrhage. The outer coat of torn and crushed vessels often becomes twisted into a kind of cord, while the intima is induplicated after the fashion of a valve. Bleeding is therefore often slight even when very large vessels have been torn or crushed. A clot having once formed extends, as a rule, up to the next collateral branch of the injured vessel. The exact nature of the changes by which a divided vessel is closed is not yet clear, and although we know that a thrombus forms, yet the reason of its formation is still disputed. The thrombus either becomes replaced by connective tissue or it- softens and breaks down. The former is the more favourable development, and consists in the gradual formation of connective tissue, which usually results from proliferation of the endothelial lining of the vessel. The endothelium is first converted into poly- morphous " formative cells," which rapidly multiply, extend into the thrombus and replace it, leaving only a pigment residue (oxy- hydrate of iron) of the original thrombus. From the vasa-vasorum new blood-vessels extend into the new tissue, converting it practically into connective tissue. The thrombus thus plays a passive part, being gradually replaced by fibrous connective tissue. These changes occur with comparative rapidity ; vascular new tissue may be found at the point of ligation eight days after operation. Where, however, the intima is extensively diseased, or where general constitutional disturbance exists, the changes proceed more slowly. Circulation is usually restored by collateral paths, the smaller vessels enlarging and conveying the blood by parallel channels. This change also is often very rapidly effected, as shown by Nothnagel's experiments on rabbits. Six days after ligation of an important vessel the muscular coats of the dilated collateral vessels were found lie HEMOSTATIC AGENTS. to be thickened. This result was formerly attributed to rise in blood-pressure, but was regarded by Nothnagel as due to more rapid movement of the blood in the vessels in question, and to the resulting increased nutritive supply. Haemostasis by a plug or thrombus is, however, only a provisional measure. Its purpose may be frustrated by suppuration occurring in the walls of the vessel and extending to the clot, which then breaks down ; or increasing blood-pressure may drive out the plug, an accident most likely to occur where the vessel is injured close to a collateral branch. In such cases secondary haemorrhage follows. Final closure of the vessel is only brought about by union of its walls, by new formation of connective tissue, and by cicatrisation of the tissues surrounding the vessel. Haemostatic agents are vefy numerous, but of very varying utility. Many have now been entirely discarded ; they persisted from pre- antiseptic times, when ligation was only too frequently followed by suppuration with separation and discharge of the ligature. They may be divided into (1) thermic, (2) chemical, (3) and surgical. Of thermic agents the most popular is cold ; it is, however, only useful for checking bleeding from capillaries or comparatively insig- nificant vessels, and even then is uncertain. The result depends on reflex contraction of the walls of the vessel and surrounding tissues checking the flow of blood. When a strong stream of water is used contraction of the tissues is increased by the mechanical stimulus. Heat is usually applied by means of the cautery ; the tissue, together with a portion of the escaping blood, is carbonised and forms a firmly adherent scab which closes the lumen of the vessel. This succeeds well in the case of small vessels, but is of comparatively little value in dealing with the larger. To check bleeding from already existing wounds the cautery should be of a bright red heat, because a firm scab is required, and one wishes to prevent the cautery adhering to the wound. When, however, it is used to make incisions the instrument should be red and should be moved slowly. Although the resulting scab is sterile, and if very small may even undergo absorption, it is impossible to effect primary union between wound surfaces so treated. For this reason the cautery as a haemostatic instrument has largely been given up, though in castration it is still used to close the divided spermatic artery. It may be remarked in passing that bleeding from hollow organs like the uterus is often best controlled by irrigations with water at a temperature of 120° F. Most styptics combine rapidly with the blood, and form with it a clot which adheres to the wound and closes the injured vessel. HyEMOSTASIS. in Some act by causing contraction of the vessel and surrounding tissues. Among those formerly employed were oak bark powder, tannin, mineral acids and their salts, alum, nitrate of silver, acetic acid, creosote, carbolic acid, alcohol, oil of turpentine, etc. Perchloride of iron in the form of liq. ferri perchlor. diluted with three parts of water is often used to moisten tampons which are applied to the bleeding spot. The most popular and effective styptic is solution of adrenalin, which quickly arrests bleeding from capillaries and small vessels. To check bleeding resulting from internal injuries, and to lessen haemorrhage during operations, calcium chloride, which increases the coagulability of the blood, gelatinised serum, extract of ergot, and hydrastis canadensis have been employed with success. In operation wounds powerful styptics sometimes retard or prevent healing by first intention, owing to their caustic or astringent effect on the wound surfaces. Surgical methods of controlling or arresting haemorrhage are repre- sented by the tourniquet, Esmarch's bandage, and rubber cord, by com- pression, ligation, torsion, forci- pressure, and acupressure. As a preventive, especially when operating on the limbs, the application of a tourniquet (Fig. 153), or a rubber cord is the means usually employed. For the horse the most primitive method consists in passing a loop of cord or webbing around the limb and tightening it by the rotation of a stout stick slipped through it. The pressure thus exercised on the vessels checks circulation, and haemorrhage during operation is virtually nil, while owing to compression of the nerves sensation below the ligature is dulled and the pain of operation greatly diminished. A more refined method is to use a rubber cord or tube. A rubber cord half an inch thick and twenty to thirty inches in length is passed around the limb above the knee or hock in a stretched con- dition. The ends are united by a simple knot or a strong cord. Fig. 153.— The tourniquet, J18 ESMABCH S BANDAGE Esmarch's bandage is most valuable when, in amputating limbs in small animals or excising some very vascular organ like the litems, one wishes to minimise bleeding. When properly applied it enables operations to be performed as though on the dead body ; no bleeding occurs, and all parts, the normal as well as the patho- logically altered, are distinctly visible. It is an elastic bandage, formed preferably of vulcanised rubber (though a fabric of rubber threads covered with cotton is some- .,--- - ^ times used), applied to the limb or ,.-'" \ organ to be removed, commencing always at the periphery. The strong / I pressure exercised by the spirals of the bandage as they advance over the tissues gradually drives the con- tamed blood towards the trunk. When the parts to be excised have thus been rendered bloodless a rubber cord is applied with considerable pressure immediately above the the arteries and practically brings The ends of the cord are secured Fig. 154. The cord Fig. 154.— Catch for rubber cord used with Esmarch's bandage. bandage. This compresses the local circulation to a standstill. by tying or preferably as shown in mg. 154. ine com stretched and slipped into the first of the incomplete cylinders ; is then carried once or twice around the limb, stretched tightly to Fig. 1o5. — Ligating an artery ; first stage. allow it to be inserted hi the second cylinder, and then sharply released. Its elasticity causes it to be firmly held in position within the cylinder. The bandage is then removed and the operation per- formed below the cord. In veterinary practice Esmarch's method is not usually applied in its entirety, the operator often being satisfied with the application COMPRESSION AND LIGATION. 119 of the cord. Generally, this modification is advisable when the tissues have undergone much change, and are infiltrated with infective fluids which might be pressed into the healthy tissues by the bandage and produce very grave results. Fig. 156. — Ligating an artery ; second stage. Compression is useful where one cannot ligate the divided vessel. The portion of the wound where the divided vessel is seated is 157. — Greig-Smith's artery forceps. Fig. 158.— Spencer Wells' artery forceps (with separable limbs for cleaning). compressed either with the finger or with a tampon of cotton wool (immediate compression). In the event of this failing, the main vessel supplying the parts is compressed at the point nearest^ the 120 LIGATION OF ARTERIES. wound, where it can be brought directly against a bone (mediate compression). This plan rarely stops bleeding completely, however, and at the end of the operation one is obliged to resort to some other method. In dealing with hollow wounds long strips cl anti- septic gauze, tarlatan, or muslin may be packed into the cavity under pressure, and the lips of the wound provisionally united by a few sutures. This usually checks bleeding from small vessels. Ligation is effected with threads of silk or catgut : chromic gut is the best. When an artery crosses the field of operation, and must be divided, it is isolated, ligatured in two places, and the section made between the two ligatures. If a vessel, whether artery or vein, is accidentally divided, the ends are grasped with forceps and strongly ligatured as high up as possible, using a surgical knot. In the case of an artery, the object is to divide the inner and middle coats, which retract, and become incurved towards the axis of the vessel, whilst the external stretches slightly, and its surfaces are brought into close apposition. When using catgut the ends of the knot may be cut short, but in the case of silk usually only one is cut short, the other being brought outside the wound unless asepsis be assured. It is withdrawn a day or two later, when the vessel has been cut through. Walls' or Greig-Smith's forceps, with large jaws of conical or cylindro-conical section, are very convenient when ligating vessels. The ligature, on being tightened, slips over the nose of the forceps, and surrounds the vessel. Immediate ligation is always to be preferred. Where it is impracticable, as when the ends of the vessels have retracted deeply within the tissues and cannot be discovered, or when the tissues are very friable and break away as grasped, mediate ligation, or ligation in the continuity of the vessel, may be performed. The instruments required are a scalpel, two retractors, dissecting forceps, a director, ligatures, and aneurysm needle (Figs. 159 and 160), i.e. a curved needle with fixed handle. The method is as follows : — • The skin is incised directly over the artery, the lips of the wound are drawn apart with retractors, and dissection cautiously continued until the artery appears. A fold of the artery sheath is then lifted Figs. 159, 160.— Aneurysm needles, H.-EMOSTASIS BY TORSION. 121 and divided, leaving the artery itself free. If preferred the artery sheath may be torn through, using two pairs of dissecting forceps. The artery is freed from its sheath for some distance as in Fig. 155 (which is semi-schematic). One margin of the sheath is lifted with forceps and drawn slightly away from the artery, around which the ligature is passed by means of an aneurysm needle. Care must be taken that only the artery, and not the accompanying vein or nerve, is included in the ligature. One end of the ligature is held with the fingers or forceps and the needle drawn back, leaving the thread around the vessel. The knot is tied in the manner before indicated, and shown in the semi-schematic illustration, Fig. 156. The ends of the ligature are then cut off short, and the wound sutured and dressed. After ligation the neighbouring parts are nourished by collateral anasto- mosing branches (Fig. 161). In injuries to large vessels, however, the existence of this collateral cir- culation is sometimes responsible for secondary bleeding from the peripheral ends should the vessel not have been ligatured both in front of and behind the injured spot. In former times it was con- sidered dangerous to ligature veins. Nowadays no distinction is made between veins and arteries. Large veins, however, should be doubly ligatured for similar reasons to those above stated, and also be- cause in the case of large veins air might possibly be aspirated through that portion of the vein nearest the heart with fatal consequences. Torsion may replace ligation in dealing with small arteries and veins. The mouth of the bleeding vessel is seized with forceps, drawn slightly forward, and the forceps rotated five or six times (limited torsion). To make quite sure of closing the vessel some surgeons continue torsion until the coats rupture (unlimited Fig. 161. — Figure'sho wing restoration of blood supply by collateral vessels after ligation of main trunk ; from a preparation of the femoral artery of a large dog eight months after ligation. 122 ACUPRESSURE. $ torsion). If the vessel is a large one, it should be held with narrow forceps, applied transversely, while the torsion forceps, held parallel to the long axis of the vessel, are quickly turned in one direction. As in ligation, the middle and internal coats are ruptured, and become induplicated ; the external coat being stretched and twisted forms a kind of cap, which covers the clot, and gives it much greater firmness. Ligation, however, is always more certain than torsion. In arterioles of considerable size, moreover, the fibrous coat may untwist, giving rise to secondary haemorrhage. Forcipressure by means of artery forceps has largely replaced other means of checking bleeding. It consists in applying to the mouths of divided vessels special forceps (Wells' form is the best), which are left in position for a varying time, sometimes until the vessels are blocked by clot, sometimes only until ligatures can be applied. If during operation a small artery is divided forceps are immediately applied. By using a number incisions may be made through very vascular tissues with little interruption or loss of blood. To keep the operative field clear they are held to one side by an assistant. It is not necessary that all should be left in position until the end of the operation ; arteries of very small dimensions, if compressed for a few minutes, no longer bleed when the forceps are removed. Should a large vessel be divided, it can be grasped and closed with Wells' forceps, and immediately ligatured ; this prevents the seat of operation being obscured with blood. Needless to say, forceps, threads, and instruments must all be aseptic, an indispensable condition if one wishes to effect primary union 'or prevent accidental infection. Acupressure never found much favour in veterinary practice as compared with human surgery, because animals are too difficult to control. At the present day it has lost much of its value, inasmuch as materials for ligaturing vessels are available which can be left permanently in position without danger. Acupressure is effected by thrusting a pin vertically into the soft tissues about three eighths to three fourths of an inch from the artery, carrying it in a horizontal direction over or under the artery, and causing it to emerge a similar Figs. 162a, 162^.— Method of practising acupressure. BANDAGING AND DRESSING. 123 distance on the opposite side of the vessel. The opening of the artery is thus pressed either against soft parts, or, better still, against a bone (see Figs. 162a and 1626). When this is ineffective or impos- sible to carry out, two needles are employed, one passed below, the other above the vessel. VIII.— BANDAGING AND DRESSING. Since the introduction of antiseptic wound treatment dressings have played a much more important part than formerly, when open wound treatment was the usual custom. They not only shield the wound from infection and absorb wound secretions but favour healing by primary intention, and retain soft parts in contact very much as callus formation fixes the broken ends of bones. Dressings are also useful to retain given parts in predetermined positions and to exercise pressure. Unfortunately, in veterinary surgical practice, dressings cannot always be applied or made secure owing to the patient's restlessness, or the position of the wound. The best materials for dressings are aseptic gauze or tarlatan, cotton wool, lint, tow, wood wool, and prepared peat. Cotton wool and gauze containing boric acid (45 per cent.), or carbolic acid (5 per cent.), or the double cyanide of mercury and zinc (3 per cent.), and carbolised tow are much used. They may be obtained ready for use. Compresses may be of linen, cotton, flannel, etc. To cause them to fit properly without creasing they must often be slit at the edges. Dressings and compresses are secured in position in various ways, the commonest being by the use of bandages. These were formerly of linen or flannel, but for surgical purposes nothing surpasses calico, tarlatan, or cotton bandages which can either be cut of suitable size and length from a large piece of stuff or, better still, bought ready for application from the surgical apparatus dealers. In addition to cheapness they have the advantage of adapting themselves readily to irregularities of surface and of being very absorbent. Flannel bandages stretch irregularly in use, and as they soon lose their elasticity finally become wrinkled. Knitted bandages are very elastic and even after long use may by proper treatment be rendered almost as effective as when new. Bandages intended for fixing parts immovably in position may be saturated with dextrin and dried. They can also be bought ready prepared, requiring only to be thoroughly moistened before use, when the turns adhere strongly, forming practically one mass. To 124 BAN1)A<;IN<;. Fig.. 1.63. promote absorption of extravasated fluids elastic bandages are very useful. Some are made of elastic thread covered with cotton or silk, others of pure rubber ; the latter, on account of their durability and the ease with which they can be cleansed, are to be preferred in spite of their higher price. By intelligent application excellent re- sults may be obtained with these bandages, though careless use of them may also do great harm. The most important point is to apply them with equal pressure throughout. A very good plan is for the operator first to test the effect of the bandage on his own person, for example on the arm. Even with apparently slight pressure he will soon find it unbearable. As such elastic bandages cannot safely be placed in unskilled hands, and as continued pressure is often desir- able, elastic stockings or gaiters can be used. They may be safely applied by any groom provided they fit properly in the first instance. As a rule bandages should not exceed 2h to 4 inches in width except such as have to be applied to the horse's body. The more slender the part to be bandaged the narrower must be the bandage, it being par- ticularly difficult to apply broad bandages without producing creases, especially in the neighbourhood of joints. Before appli- cation the bandage must be rolled ; one end is first folded several times on itself, forming a small cylinder which serves as an axis for further rolling ; the best method is shown in Fig. 163. Fig. 164. Material for and form of bandages. 125 Fki. 166. Bandages may be either single, double, or many tailed. The single ended bandage, forming a single roll, is that most in use. The double ended (Fig. 164) is rolled from both ends towards the centre, as is the multiple bandage, which, however, is now seldom seen. A very useful appara- tus for rolling band- ages is that shown in Fig. 165. Bandages should always be applied from the periphery towards the centre, never in the oppo- site direction, which would lead to con- gestion of the veins and lymph vessels. This precaution is often overlooked, the operator commencing in the middle of a limb. The simple experiment of applying a bandage to the middle of the forearm will soon convince anyone of the undesir- ability of this course ; the veins of the hands become enormously distended. In hoofed animals we cannot commence at the extreme periphery, but the bandage should certainly be- gin about the coronet and not, as is so commonly the custom, above the fetlock- joint. Simple circular turns, by which the bandage is applied to one spot alone, are now seldom employed for the reasons previously given, but they form the commencement and end of other methods. In Fin. 167. spiral bandaging the upper edge of each turn is covered by the lower portion of the next in order ; as each succeeding turn is applied it is temporarily fixed in position by the index finger or thumb of the left hand until the next turn overlaps and fixes it in position. The first circular turn should be double to give greater security ; those following take a gradual upward spiral course. On regions of conical section like the forearm, 1 26 BANDAGING. or such as are not truly cylindrical, spiral bandaging can only be successfully carried out by using very elastic cotton bandages, other- wise the lower edges of the bandage always project. This, however, can be avoided by reversing the bandage at each turn as shown in Fig. 166, the upper and lower edges changing places. The bandage, held in the hollow of the right hand, is drawn tight, rotated, and the folded point fixed with the thumb or index finger of the left hand. The bandage is then rapidly passed round the limb, and again draws tight, the thumb of the free hand keeping the fold flat meanwhile. These precautions, however, are scarcely necessary when using knitted, elastic, or calico bandages, especially where the latter are moist. To maintain pressure on a joint like the fetlock the figure- of-8 shown in Fig. 167 is useful. The bandage is passed once or twice around the pastern, thence obliquely upwards over the anterior surface of the fetlock, behind the joint and then forwards and down- wards in a direction opposite to that of the previous turn. The position of each succeeding figure-of-8 should be slightly varied so that the entire surface of the joint is covered. To secure the degree of tension required to keep the bandage in place without causing undue presure at any point requires some practice. Until this know- ledge is acquired it is better to err on the side of slackness. When moist applications are needed it is often best to soak the bandage before use, otherwise it contracts when wetted and may cause greater pressure on the diseased part than is intended. For the same reason moist bandages, which will afterwards be allowed to dry in position, may be drawn rather tighter than if they had been applied dry, the pressure diminishing as the moisture evaporates. It is not possible to fix dressings in all positions with bandages. In many cases considerable ingenuity is required to secure the desired fit, and the following illustrations (redrawn from Bourgelat) are intended to assist operators in this task. In the illustrations (Fig. 168 et seq.) indications are given of where a fold or a gusset is needed and where a portion of the cloth is to be reinforced with lining. In many places, however, even these applications do not meet all the requirements of antiseptic wound treatment. Thus after removal of the large growths which occasionally form at the shoulder in consequence of bruising with infection, Bayer preferred the following device : — He first inserted sutures of relaxation, using drainage-tubes of large size. The sutures were passed at a distance of 1^ inches from the margin of the wound and comparatively deeply ; the number inserted naturally depending on the size of the wound. A drainage-tube was then inserted and the wound closed with closely MODE OF APPLYING BANDAGES. 127 ss Fig. 168. Fig. 169. Fig. 170. Fig. 171. Fig. 172. Fig. 173. 128 SURGICAL DRESSINGS. placed interrupted sutures. Bayer insisted on the importance of drawing up a fold of skin, thus producing a ridge \ inch high before inserting these sutures. A large piece of iodoform gauze was spread over the whole field of operation and fixed to the rubber tubes used for securing the sutures of relaxation. The gauze covered the drainage-tube. The horse was then allowed to rise and the space marginated by the rubber tubes was protected with a pad of dressing material which was caused to press on the wound by thrusting broad strips of thin elastic wood, similar to that used in the manufacture of hat boxes, under the rubber tube on either side. This brought the surfaces of the wound together and facilitated union. The trifling local prominences caused by the stitches did not prevent the appli- cation of a well-fitting collar and usually disappeared in a month or two, leaving a scarcely visible linear scar. The dressings used in fractures of bones may be divided into two kinds, viz. those of a temporary character — -termed provisional — and those intended to be more lasting — permanent dressings. The choice for the first dressing is often very restricted, and whatever first comes to hand may require to be used. In this case broad strips of linen or even of sacking are sometimes first applied as a padding and support, and the splints, formed of flat pieces of wood, are applied on either side of the long axis of the bone and fixed in position by cords or straps. Pieces of wood may be replaced by bundles of straw. The broken part being thus protected the horse should be removed as rapidly as possible to the stable, and the permanent dressing applied. If time permit the supporting pieces of wood may be sewn between linen pads. To increase the firmness of the dressing rolls of straw, lengths of sole leather, straw board, or pieces of lead moulded to the shape of the part, can be employed in place of wooden splints. Permanent dressings are prepared with starch, dextrin, plaster, tripolith, glue, gutta-percha, plastic cardboard, and poroplastic felt. When applying any of these care must be taken that the broken parts are first replaced as nearly as possible in their natural positions, and so retained until the dressing has become quite hard. The dressing must not press unduly on any point as this would cause sloughing of the skin, a complication specially liable to occur where prominent bony processes have to be included in the dressing. The portions to be covered and their immediate neighbourhood are there- fore first supported by the application of a sheet of linen, over which wadding or some soft material is thickly applied and is retained in position with a soft bandage. Instead of wadding, soft flannel WOUND AND FRACTURE DRESSINGS. 129 jt-A Fig. 174. Fig. 175. Fig. 170. Fig. 177. [<* ...-ik- .. { (' Fig. 178. Fig. 179. 130 STARCH, GLUE, PITCH AND OTHER BANDAGES. bandages can be employed ; these perhaps fit better and are pre- ferable. After thus filling up all irregularities of contour and bringing the dressing to a level surface, the permanent bandage, impregnated with some hardening material, is applied. A common error is to apply the dressing to the fractured point alone. It is, however, absolutely necessary to extend it upwards beyond the next joint and downwards as far as the hoof or claw. Any weight thrown on the limb is thus transferred to the bandage, which acts somewhat like a cylindrical crutch, the broken bone being relieved of pressure and preserved from any movement likely to prevent union. In applying starch handages the parts are padded as described, and cardboard splints, rendered pliable by immersion in hot water, are applied. These are fixed in position with bandages completely saturated with starch. Some operators prefer to omit the cardboard splints. The gravest disadvantage, however, of this dressing consists in the fact that it requires twenty-four hours to become thoroughly hard. Starch may advantageously be replaced by ordinary glue, prepared as for carpenters' use. Dextrin bandages are applied like starch bandages but are somewhat dearer. The hardening mixture is usually composed of : Dextrin 100 parts, spirit of camphor 60 parts, water 500 parts. Glue bandages are sometimes used, but harden rather slowly. Bandages or strips of linen are smeared on one side with melted glue, dried, and rolled up with the dressed side outwards ; they are immersed in hot water just before application. Another method consists in thoroughly saturating ordinary bandages in hot thin glue immediately before use. Pitch bandages are prepared by drawing long strips of linen through fluid pitch and hanging them up to cool. In use compara- tively short lengths are applied at one time as each must be softened and made adhesive by warming. They are extremely unpleasant to handle. Water glass is utilised for permanent dressings by painting an ordinary bandage with a solution of water glass as each turn is applied, or a very loosely rolled bandage may be saturated with the fluid before use. This dressing hardens more quickly than starch, but not so rapidly as plaster or tripolith. It is, however, lighter and more elastic than plaster. Water glass solution, when mixed with chalk, magnesite, Portland cement, etc., produces a stronger dressing, which also hardens more rapidly. The most generally useful, however, are plaster and tripolith bandages. 131 Fig. 180. Fig. 182. Fig. 183. Fig. 184. 132 PLASTER BANDAGES. bandages. Modellers' dry plaster is rubbed into ordinary loosely woven bandages which are then rolled up, care being taken that as large a quantity as possible of the plaster is retained in the material. Just before use they are saturated with water (preferably containing a little dissolved alum, which hastens setting) ; they are then gently squeezed and at once applied to the parts, which have previously been padded as above described. The first folds should be applied around the free extremity of the limb and ban- daging continued upwards, care being taken not to use much pressure. The piece of linen placed next the skin should extend beyond the limits of the bandage so that when the latter is complete the edges of the linen can be turned up after the manner of a cuff, enveloping the wadding or other padding material. This gives the dressing a rounded edge, and prevents any pressure on or rubbing of the skin. After complete application the surface of the dressing may be smoothed with the wet hands, or some thin plaster may be spread over it and smoothed off. Depending on its thickness the bandage sets in from fifteen to thirty minutes, during which time extension or flexion of the limb must be prevented. Plaster of Paris, if long kept or allowed to become damp, sometimes fails to set, but a little care in storage will prevent this. If desired, setting may be delayed by adding glycerine to the water used in mixing the plaster. To further support the dressing thin pieces of wood or splints of zinc or tinned iron may be inserted between the layers. Instead of pure plaster a mixture of one part cement to two or three parts of plaster has been recommended. It appears to present no special advantages. Tripolith, a grey powder the composition of which is unknown, is sold commercially. It hardens in much less time than plaster, and has the advantage of keeping well, even in open vessels. Dressings made with it are lighter and cheaper than those made with plaster, but as it hardens so very rapidly only one or two bandages should be moistened at a time. All the above dressings can be made waterproof by varnish or shellac solution, which also gives them greater durability. While the plaster is setting it is absolutely necessary that the limb should be retained in the proper position, as any movement breaks and therefore usually entirely spoils the dressing. For this reason small animals must be kept lying ; larger animals should be placed in slings. These dressmgs, especially when of plaster, are often very difficult to remove, especially if one wishes to remove the bandage in two BANDAGES. 133 i / i Fig. 187. Fig. 18G. 34 SURGICAL DRESSINGS. parts so as again to utilise it. To facilitate the operation special scissors have been designed, but they are very costly and rapidly become worn, while the same object can be attained almost as well, though somewhat less rapidly, with a strong pocket-knife. The line Fig. 193. through which the incision is to be carried is first thoroughly moistened with warm water or, better still, with hydrochloric acid. In the latter case, of course, the instrument used for cutting suffers very considerably. Fig. 195. Fig. 194. Gutta-percha dressings are less frequently employed in veterinary surgery on account of their cost. The material is in the form of flat plates, which become plastic on immersion in warm water, and can then be pressed closely in contact with the injured part, which should first be well oiled. The soft mass adapts itself with the greatest MASSAGE. 135 facility to all prominences and depressions, and rapidly becomes hard under a stream of cold water. The advantages of gutta-percha are its slight elasticity, the ease with which it can be kept clean, its impermeability to fluids, and the facility with which it can be removed. Moreover, the same material may be used repeatedly, so that its first cost is really the chief objection. For small animals like dogs it is particularly useful, and in fracture of the lower jaw in larger animals it renders excellent service, a kind of hollow splint being formed, in which the jaw is embedded. Poroplastic felt consists of felt impregnated with a resinous solution. It is made in sheets of varying size and thickness up to three feet square and | inch in thickness. By immersion in boiling water or exposure to dry heat it becomes quite plastic, and may readily be moulded to the shape of the injured part. It becomes firm on cooling, but a " setting " process continues for some time afterwards, so that its greatest strength is not attained for six or eight hours. Its porous character readily permits of transpiration, and the skin is therefore much less apt to become macerated by retained perspiration as occasionally happens when gutta-percha splints are used. The writer has seen very excellent results from the use of this material in the setting of fractured limbs in racehorses. IX.— MASSAGE. The term massage includes various forms of mechanical treat- ment, which, accordmg to the demands of the case in hand, are either applied singly or in combination, in order to bring about particular curative results. We may distinguish — i. Gentle stroking of the diseased parts with the fingers or open hand in the direction of the flow in veins and lymph vessels, that is, from the periphery towards the centre. The maximum pressure to be applied in such case should at first not exceed that produced by the weight of the operator's hand. 2. Brisk rubbing or pressure followed by stroking from the periphery towards the centre. 3. Beating of the parts with the open hand or fist, or with the edge of the hand, or a special percussion hammer. 4. Kneading, in which the affected part, usually a muscle or tendon, is lifted as high as possible with one hand, and then squeezed in precisely the same manner as one would compress a moist sponge to squeeze out its contents. L36 MASSAGE. 5. Active and passive movements. To prevent formation of pustules at the roots of the hair, which would put a stop to further massage, it is usual in human practice to shave the affected spot and coat the parts with some lubricant, but this is not absolutely needful. According to the effect produced massage is applied for periods extending to an hour or more daily, provided, of course, that the reaction in the affected parts permits of it. At first massage generally causes pain, which, however, dis- appears on each occasion during the process, and is replaced by a pleasant feeling of warmth, flexibility, and increased power in the parts. From the above it will be seen that massage favours increase of bodily strength and endurance, but its best effects can only be obtained by practice and by a thorough knowledge of the patho- logical processes to be combated, the exact anatomy of the diseased parts, and the physiological effects of the different massage manipu- lations. Experiment shows that the effects vary, similar manipu- lations being irritant or soothing, inclined to produce or to dissipate congestion, and to alleviate or arouse pai •, according to the idio- syncrasy of the patient. The operator must first clearly conceive the changes he desires to effect in the diseased parts, as only then can he reasonably expect to effect improvement, or even to know whether massage is likely to be of benefit apart from choosing the exact system to be followed in the case in question. The action of massage depends on its favouring and increasing absorption, accelerating circulation, and relieving pain. By stroking centripetally, not only is circulation in the collecting vessels locally stimulated and tension relieved, but mechanical congestion in parts removed from the centre is lessened and exuded lymph absorbed, while extravasations in the tissues themselves are distributed over a larger area, are brought in contact with numerous absorbents, and are mechanically assisted in entering them. For these reasons it is best to commence not at the diseased spot itself but on the central side of it, and gradually to approach the diseased spot in order to first clear a space, into which the exudate or extravasation may more readily flow. Mosengeil's experiments prove it possible to remove fluid even from joints by pressure and stroking. He injected Indian ink into the synovial cavities of rabbits, and in two or three minutes reduced the joints to their normal form by massage. On post-mortem examination the Indian ink was found in the nearest lymphatic channels, vessels, and glands. USES OF MASSAGE. 1 37 Massage promotes active absorption, diminishes swelling of tissues. and therefore pressure on the sensory nerves they contain, a fact partly explaining the decrease of pain. Massage also directly stimu- lates nerves, at first increasing, but afterwards diminishing their irritability. Newly formed adventitous tissue and vessels may be broken down by powerful pressure and rubbing. The extravasate thus produced, together with the cells of the broken down tissue, may be rapidly absorbed. Infiltrations may be dispersed by repeated and long continued massage, and callus formations, so long as they are not of bony hardness, may be markedly diminished. Muscles are stimulated to contraction, which, as is well recognised, constitutes an important factor in favouring absorption. Not only healthy but relaxed and semi-paralysed muscles again respond to stimulation, as shown by the electric current, a fact explained by the increase in supply of nourishment to the part. Muscular- exhaustion following exertion is soon removed by kneading, both because metabolic products which accumulate in muscles during work are more rapidly absorbed, and because at the same time nutritive material is brought to the parts. The capacity of the muscle for exertion may even become greater than it was before the period of exhaustion set in. Massage is of special service in diseased conditions dependent on hyperemia, extravasation, exudation, thickening of tissue, adhesions, in short, on the results of aseptic inflammation, the products of which therefore not being of bacterial origin may be absorbed into the blood without producing bad results. Massage may be resorted to in animals affected with aseptic inflammatory swelling resulting from pressure, thickening of the skin and sub- cutaneous tissue of the extremities, bruising of the margins of joints, the early stages of exostoses, periostitis, inflammation of tendons and tendon sheaths, adhesions, distension of synovial and mucous bursa?, induration of the udder, impaction of the bowels, tympanites, etc. In the treatment of most of these diseases friction, which we must now regard as a kind of massage, has been utilised since ancient times. It is true that the stroking or rubbing is as often as not in the opposite direction to that of the circulation, and absorption, if occurring, must take place by collateral paths, inasmuch as the diseased spot lies between the material which is thus pressed towards the periphery and the centre of circulation. Furthermore, rubbing differs from stroking, inasmuch as considerable pressure is employed, and new tissue and recently formed vessels may quite possibly be 138 ACTION OF MASSAGE. broken down, the further changes then occurring as above noted. The same is true of the system of pressing on and rubbing recent exostoses with a flat piece of wood, which was customary in former times, but the comparative inefficiency of this rudimentary massage lies not so much in the fact of the operator failing to observe the proper direction as in his altogether neglecting treatment until far too late. Long ago Bayer pointed out that in veterinary practice we cannot expect the extensive and successful application of massage which obtains in man. We have already noted that in man the hair is removed and the skin lubricated to prevent pustular eruption. In animals, however, we cannot shave an entire limb, and even if the hair were removed we are able to apply massage in the proper centripetal direction only in a few places, like the neck and back ; at almost all other spots where massage is to be employed we are forced to work against the direction of the hair, which is very difficult. Bayer attempted to overcome this difficulty by the use of massage rollers consisting of small hollow cylinders covered with, or entirely constructed of, rubber. Such instruments, however, cannot replace the hand, which so readily adapts itself to the varying contour of the body and allows so much more perfect an estimate to be formed of the pressure employed than can be obtained in any other way. The exact degree of pressure to be used is difficult to judge, and can only be learned by practice and experience. Excess causes injury and delays improvement, as one often sees when the treatment has to be left in lay hands. Bayer preferred to forego massage altogether rather than leave the manipulation to the owner or coachman. The pain caused by pressure and kneading, especially where much force is employed, sometimes renders it necessary to resort to means of restraint. The action of massage is considerably increased by sub- stituting for mere lubricants ointments containing substances which promote absorption. Active and gradually increasing exercise produces similar results, chiefly by improving blood and lymph circulation and increasing metabolic changes. Massage is applicable to a large number of diseases and their sequelae. In infiltration of the cornea with milky deposit, not due to cicatricial formation, massage is applied in the form of circular and radiating rubbing. As horses with disease of the eye usually resist interference, it is necessary to proceed with caution. The hand is first passed over the side of the face furthest removed from the eye and gently advancedjmore and more closely to the diseased MASSAGE. 139 eye. Placing the points of the index and middle fingers very lightly on the upper ej^elid the lid is caused to move over the surface of the cornea with circular and radiating movements. Very good results may be obtained in this way alone, but a small quantity of some resorptive, like the yellow or red oxide of mercury ointment, may, in addition, be introduced into the conjunctival sac. Bayer also recommended iodoform ointment and iodoform in powder. Massage is particularly valuable in inflammation of tendons and in recent cases of thickening of the tendon, but only when the con- dition is circumscribed. When the entire tendon is thickened the effect is much less satisfactory. On the other hand, excellent results may be obtained in thickening of the flexor pedis perforans, though considerable patience and perseverance are required. The foot being lifted, the upper part of the thickened spot is grasped between the thumb and fingers and kneaded, at first very gently, afterwards more strongly, but without excessive pressure. The operator gradually works further down. Manipulation being complete, the horse is exercised for a short time and a wet bandage applied. In dispersing the soft enlargement resulting from periarthritis the thumbs are most employed. The periphery is first manipulated, the thumb being applied to the soft tissue with considerable pressure. This tends to break up the soft deposit, which is then further dis- persed by powerful stroking movements with the thumb. The horse is afterwards exercised. Passive movements of the joint can only be carried out satisfactorily in small animals. Vogel recommends massage in various diseases of the udder. Old practitioners appear to have recognised its good effects, as shown by their advising frequent milking, which really acts as a kind of massage. Vogel, however, lays stress on the suggestion that the veterinary surgeon himself should first carry out the operation, because rough or excessive manipulation often causes a relapse. The hard masses of tissue are grasped and kneaded or rolled under the fingers. Massage of the abdomen is most useful in ruminants and dogs. In ruminants it arouses peristalsis, so that in fifteen to twenty minutes the overloaded and torpid rumen may often be set in action. The best method of manipulation is to station on either side of the abdomen a man who, laying his clenched fists close together on the animal's side, makes regular powerful kneading movements from below upwards. Where severe tympanites, or obstinate impaction of the omasum exists, or rumination has been suppressed for several 140 I'HLEBUTOMY. days, the power of the operator's arms is insufficient, and Vogel suggests the operator sitting on a stool and using the soles of the feet. Counter-pressure must, of course, be exercised on the right side. In dogs the abdomen can be massaged with the animal either in the upright or prone position. The points of the fingers alone may be used, or where over-distended portions of the bowel can be felt the open hands may be employed. The coil of intestine is grasped with the fingers and the contents broken down and forced onwards. With the animal in the standing position one operates in a similar way, the points of the fingers being slowly pressed from either flank into the depths. Portions of bowel may be kneaded and peristalsis aroused by suddenly releasing the parts after subjecting them to steady pressure. In this way even severe con- stipation may be cured and more serious operation often avoided. X.— PHLEBOTOMY. By phlebotomy is meant the surgical opening of a vein for the purpose of removing blood. Although bleeding is almost invariably practised on veins, arteries may be utilised for the same purpose, and the old term blood-letting included venesection or phlebotomy and arteriotomy. Bleeding from capillary vessels is usually effected by scarification or the application of leeches. Bleeding may be divided into general and local. General bleeding consists in removing a large volume of blood with the object of lowering blood-pressure throughout the body ; local bleeding, on the other hand, is undertaken to reduce the quantity of blood in the part operated on or in its immediate vicinity, i.e., to improve the conditions in a circumscribed area. In former times bleeding was popular in all acute and feverish conditions, and was so excessively practised that a reaction naturally set in. It has now almost fallen into desuetude, a result accelerated and confirmed by the entirely different views now held as to the value of general bleeding. In bacteriological laboratories, of course, bleeding is a necessary preliminary to the preparation of protective sera, and is also resorted to for obtaining blood for microscopical or bacteriological experiments. The periodical bleeding of animals in spring to keep them in good health is still practised in a few pails of the country, but is rapidly dying out. The innate vitality of ancient superstitions is well illustrated by its having survived so long. CHIEF RESULTS OF BLEEDING. 141 It would appear that venesection plays no great therapeutic role, and when we recall that it is contra-indicated both in extreme youth and age, in constitutional weakness, pregnancy, etc., there is little wonder if it is now comparatively little practised. Its most important indications are in dangerous conditions resulting from marked dis- turbance of circulation in important organs like the lungs and brain. It is also valuable in other diseases like laminitis and lumbago, in which, however, its exact modus operandi is obscure. It is known that the reduction in quantity of the circulating fluid is at once followed by diminished blood-pressure in all the vessels and changes in the circulation favourable to the relief of local congestion. The blood withdrawn contains a large quantity of nutritive material and , blood-corpuscles, both of which are of great importance to the organism when struggling with microbic infections ; in such diseases, therefore, blood-letting is seldom advisable. As it is also known that inflammatory processes in the body most commonly result from infection, this fact renders blood-letting still more questionable as a means of combating inflammation. On the other hand, a certain amount of infective or toxic sub- stances is also removed with the blood, but as general bleeding weakens the patient, and as active resorption from the great body cavities follows, it may happen that a greater amount of injurious material is eventually absorbed than is removed from the circulation. „As mentioned, active absorption from the tissues and body cavities follows bleeding, and the fluid constituents of the blood are thus replaced. This explains the value formerly attached to the practice as a means of promoting resorption. In opposition to this is the fact that the proportion of water in the blood is thereby relatively increased, and with it the tendency to fresh exudation. Experience shows, in fact, that little can be expected of bleeding in this direction. Bleeding is followed by a temporary increase of tissue metabolism, as shown by augmentation in the quantity of nitrogenous compounds and phosphoric acid voided in the urine. Such a result can scarcely be interpreted as favouring recovery. At the present day horses and cattle are almost invariably bled from the jugular vein ; formerly it was the custom to bleed from the subcutaneous thoracic vein in diseases of the chest, from the mammary vein in diseases of the udder, and from a digital vein in diseases of the foot, but experience slowly convinced operators that no advantage was thus gained. The jugular vein is now almost invariably chosen because it is easy to find, conveniently situated 42 PHLEBOTOMY INSTRUMENTS. as regards height, etc., and while blood-pressure within it is low, a considerable volume of blood may be obtained in a short time. It lies in the " jugular furrow," formed above by the mastoido-humeralis and below by the sterno-maxillaris muscles. Beneath the skin and loose connective tissue lies the panniculus, which, though very thin in the upper portion of the neck, attains half an inch in thickness in the lower. In the upper half of the jugular furrow " the vein rests on the subscapulo-hyoideus muscle, which there separates the vessel from the carotid artery ; but in the lower half the vein rests on the side of the trachea, and is in direct contact with the carotid, which lies above and. slightly internal to it." The point chosen is the junction between the upper and middle thirds of the neck, Fig. 196. — Lancets for venesection. where the subscapulo-hyoideus muscle intervenes between the vein and the carotid artery, which is therefore less likely to be injured. The average quantity of blood abstracted at one time is, in the ox, 10 to 16 pints, the horse 8 to 12 pints, the pig 1 to 1| pints, sheep f of a pint, and dog \ a pint, in fowls 2^ to 10 fluid drachms ; individual peculiarities, however, must be taken into account in each case. Instruments. The simplest instrument is the lancet. Several forms are used, the varieties of which are shown in Fig. 196. The English lancet (a) has a relatively obtuse point ; the German (b) is somewhat more acute ; in the Italian (c) the blade is narrower from the commencement, and the cutting edge relatively long and slender ; d is the sabre-shaped or abscess lancet, having one convex, and one concave cutting edge. To bleed with the lancet, though apparently easy, requires con- SPRING FLEAMS. 143 siderable practice ; the varying thickness and resistance of the skin in different animals making it difficult to judge of the exact amount of pressure required to open the vein without transfixing it. For this reason other instruments have come into use. The most popular of these is the fleam (Fig. 197). The handle extends some- what beyond the insertion of the actual cutting part, and is intended to prevent the instrument entering too deeply. Sometimes the back Fig. 198. Fig. 197— Simple fieain. of the handle is provided with a broad surface (Figs. 198 and 199) on which the blow of the blood-stick is delivered. Combined fleams having a number of blades in one setting are also common (Fig. 200). The fleam is caused to penetrate the vein by a sharp blow from the hand or blood-stick (Fig. 201). With the latter the necessary force can better be estimated, and the inconvenience of either failing to penetrate the vessel or completely transfixing it equally avoided ; in delivering the stroke the arm should not be moved as a whole, but only from the elbow. 144 SPRING FLEAMS. Spring fleams (Figs. 202 and 203) are intended to overcome the foregoing difficulty. The case of the fleam is provided with an opening (C) for the passage of the fleam (F), which is withdrawn into the case and set by drawing back the cocking lever (.4), leaving the plate (C) free for application to the vein. Having placed the instrument accurately in position the operator depresses the trigger (D), releasing the fleam, which makes a rapid to-and-fro movement, dividing the skin and opening the vein. As the instrument is readily placed in position, always cuts in the right direction and to the right length and depth, and can be regulated, it continues popular, despite its being complicated and difficult to clean. Fig. 202.— Spring fleam ; old form. Fig. 203. — Spring fleam ; later form. When bleeding oxen a bleeding string is required, i.e. a cord provided at one end with a ring. By passing the cord round the base of the neck and through the ring and drawing it tight, temporary engorgement of the jugular is produced, which facilitates operation. Except for stallions and very heavy, fat animals the cord is not required in equine practice. The blood should be received in a vessel of measured capacity, so that the amount removed may be acurately known. The skin wound is closed with a pin suture, or the ordinary interrupted suture. A word of caution is required against using hairs from the mane or tail to complete the pin suture, as was the OPERATION ON THE HORSE. 145 old fashion. These hairs not infrequently infected the wound and produced phlebitis. Operation on the horse. When using the spring fleam it is of little importance on which side the operation is performed, though some slight advantage accrues from selecting the right. The same is true of the lancet, but the fleam can be used most conveniently on the left. At the. junction of the upper and middle thirds of the neck a small area of skin should be shaved and disinfected (Figs. 204 and 205), this preparation minimising the danger of Ficj. 204. — Bleeding with the spring fleam ; off side. Fig. 205 -Bleeding with the spring fleam ; near side. phlebitis. The head is held slightly elevated by an assistant. Troublesome horses may be twitched, and the fore-foot on the side of operation may be lifted. When using the ordinary fleam the horse's eyes should be covered, because at the moment of striking the blow the animal is apt to start, defeating the operator ; but of course this is not likely to occur in using the lancet or spring fleam. Having cocked the spring fleam, the operator stands beside the animal's shoulder, and with the thumb or fingers of the left hand compresses the vein, causing it to be distended. Should there be any doubt as to the exact spot to select, the 140 JUGULAR riTLEBOTOMY. pressure may be relaxed and repeated once or twice, when the rising and falling of the vein will render its position evident. Immediately it appears clearly the plate of the fleam is adjusted just over it and parallel with its long axis, the trigger is gently pressed, and the incision made. The fleam is then removed, but compression of the vein below the incision must be continued until the necessary quantity of blood has been obtained. If the vein has only been stabbed, the blood flows in drops or in a very thin stream. In such case operation should not be repeated at the same point. Sometimes the blood at first flows in a thick stream, but soon diminishes in spite of continued compression. This is due to the skin having slipped to one side and covered the wound in the vein, or to a fragment of subcutaneous tissue having inter- posed itself. By slightly moving the skin or the horse's head, or by inserting the finger in the animal's mouth and so causing it to make chewing movements, the flow can be restored. Occasionally the vein is opened over a valve, which falls into the wound and obstructs the stream. Jets of bright red blood mixed with the darker stream show that the carotid has been opened ; and if the wound be large the animal may bleed to death, unless the carotid be immediately ligated. The vessel should be firmly compressed by an assistant, the existing cutaneous wound enlarged for a distance of three to four inches, the subscapulo-hyoideus muscle divided, and the carotid exposed by blunt dissection. The artery should be grasped with the fingers, drawn forward, freed from the nerves which accompany it, and, on account of the collateral circulation, doubly ligated. Care must be taken in separating the recurrent and other nerves and in cleansing the wound, as injury to the nerves or irritation produced by local suppuration may be followed by cardiac disturbance, dyspnoea, paralysis or " roaring." Other methods like continued compression of the artery and closure of the skin with sutures have been recom- mended. Compression might in isolated cases be followed by haemostasis, but closure of the skin wound is dangerous. Experiment shows that a large hematoma usually develops, and pressure on the trachea may become so severe as to threaten suffocation. Sometimes a small artery in the region of operation is divided, and gives the impression of the carotid having been injured. Injury of the vagus or sympathetic nerve seldom occurs. Perforation of the trachea can only be caused by gross carelessness, but if opened sufficiently for blood to enter the lungs, it might give rise to trouble- some symptoms. PRECAUTIONS DURING AND AFTER BLEEDING. 147 The low or even negative blood pressure in the jugular vein renders it specially convenient for venesection, but at the same time entails a certain danger of air being aspirated into it, with possibly a fatal result. Usually, even if the vein be not compressed below the incision, sufficient blood flows from above to preserve a slight positive pressure. But a deep inspiration may be followed by so rapid a rush of blood towards the heart as dangerously to favour the indraught of air through the wound. This is not a frequent accident, and it cannot well occur while the escaping stream of blood is strong and full ; though it may happen after the stream slackens or ceases. Compression of the vessel above the wound, as sometimes happens from the patient leaning against the manger or on the collar shank, is favourable to the aspiration of air through the wound. For this reason the cutaneous wound should always be sutured. The sudden or rapid entrance of a large volume of air into the jugular is accompanied by a hissing, gurgling, or sucking sound at the wound, followed by intense dyspnoea, dilated pupils, pallor of the mucous membranes, and a peculiar churning noise which is heard over the heart ; at once the horse staggers or sways to and fro, falls to the ground, and may die in a few minutes. At one time insuffla- tion of air into the jugular was frequently resorted to in destroying horses. The vein was opened with a knife, a cannula or pipe-stem inserted, and the operator — of good lung capacity — with his mouth applied to the tube, blew as strongly as possible, the horse falling and dying without a struggle. The mechanism of death from aspira- tion of air into a vein has not been satisfactorily ascertained. It has been supposed that the spumous or frothy mixture of blood and air produces distension and paralysis of the right side of the heart and consequent arrest of the circulation. Sufficient blood having been taken, the skin is closed either with a pin or interrupted suture. In the former case the pin is cautiously removed in thirty -six to forty-eight hours, the parts being supported with the fingers of the left hand whilst those of the right rotate and remove the pin. In closing the wound care must be taken not to exercise much traction on the edges, as this might cause separation of the skin from underlying tissues, and extensive extravasation. Similarly, if during bleeding the outer opening be obstructed, blood accumulates under the skin. Such extravasation would be of little consequence were it not that by compressing the vein it may lead to thrombus formation, and that it always supplies a favourable medium for the further development of the micro-organisms which L 2 14ft VENESECTION BY FLEAM. almost inevitably enter. Failure to remember these facts, and to observe necessary cleanliness, account for most cases of suppuration and phlebitis and the complications which follow them. To prevent the animal injuring or infecting the wound, by leaning against or rubbing itself on the manger, etc., it should be secured on the pillar reins or tied up short. Nor should it be worked soon after bleeding, because the pressure of the collar on the vein or the rise in blood-pressure consequent on exertion may cause the lips of the wound to spring open. In operating with the spring fleam on the left side, the instrument is held in the reversed direction — that is, with the blade pointed downwards (Fig. 205), or the vein may be compressed with the right hand and the fleam held with the left. The right jugular is easier to open with the lancet (Fig. 206). The position of the operator is similar — -that is, near the animal's shoulder. After wetting and smoothing the hair the vein is compressed lightly below the point of operation and caused to appear distinctly. The in- cision is, as before, at the most prominent point and close to the operator's fingers, because here the vein is more or less fixed. The lancet is thrust inwards and slightly upwards, so as to produce a sufficiently large wound, though care must be taken not to absolutely slit open the vessel, as is sometimes done from over-anxiety. It then becomes difficult to stop the flow, and it may be necessary to ligate the vein, in addition to which there is danger of air entering the vessel. The incision should be in the centre line of the vein ; the upper (or posterior) aspect of the vessel must be avoided, as injury to the carotid artery may readily result from incisions in this direction. In using the ordinary fleam (Fig. 207) the operator, standing opposite the animal's left shoulder, holds the fleam lightly between the index finger and thumb of the left hand, compresses the vein with the other fingers, and with a short, smart blow from the blood- Fio. 20f>.— Bleeding; with the lancet. BLEEDING CATTLE. H9 stick, or failing this, from the edge of the right hand, drives the fleam into the vein. The fleam must be held exactly at right angles to the skin over the highest prominence of the vein, otherwise the vessel will be opened on one side or the instrument will slip past it. Dieckerhoff and Caspar recommended a special trocar and cannula for bleeding. As this instrument had been used for some years for intra- venous administration of drugs, it occurred to them that it might be equally useful for withdrawing blood, especially where it was desirable to shield the withdrawn blood against contamination, as in preparing protective serum. The cannula has the great advan- tage over the fleam that it can be inserted several times at the same place. In operating, the vein is raised, the skin divided, and the vein exposed. The operator, standing on 1||k,, y^ the animal's near side, \ ml then thrusts the cannula, carrying its shield, steadily into the vein for a distance of three or four inches, when bleeding follows. Some dexterity is re- quired, but the method is particularly useful for laboratory work, and avoids almost all the risks formerly ap- pertaining to phlebotomy of the jugular. When the necessary amount of blood has been abstracted, a blunt trocar is inserted into the cannula to prevent air entering the vein, and the combined instru- ment withdrawn. The wound is dressed antiseptically and closed with a single suture, or may be left open. In cattle the jugular vein is also opened. The animal's head is raised by grasping the horns and the eyes covered. The hair is removed from the seat of operation, the bleeding cord previously mentioned adjusted, and the vessel opened just above the point of compression by means of the fleam. The operator stands as in bleeding a horse. In small cattle one may even stand on the side opposite to that of operation and lean over the animal. This method has the advantage that the operator cannot well be struck by the animal when, as occasionally happens, it kicks in a forward direction. Fig. 207.— Bleeding with the fleam and blood-stick. 150 VENESECTION. On account of the loose arrangement of the skin in oxen it is not necessary, though it is advisable, to insert a suture. Bleeding from the mammary vein was formerly practised in diseases of the udder and of abdominal organs, but possesses no special advantage over bleeding from the jugular, while it is less easily carried out, and the wound is very liable to infection. Sheep and goats may also be bled from the jugular, but as a rule the facial vein in the neighbourhood of the fourth molar is selected. It yields little blood, but this is by no means an unmitigated evil, as sheep and goats are very liable to serious symptoms after bleeding. As in swine the jugular lies deep and is covered with fat, it is seldom opened, the lingual vein being preferred. A wooden rod being thrust between the teeth, the tongue is drawn forward, and Fig. 208. — DieckerhofFs bleeding cannula, the vein opened just over the frsenum linguae. Bleeding ceases spontaneously. In addition the transverse facial and anterior auricular veins are occasionally opened. The internal saphena vein of the hind limb is also the seat of operation. It is compressed by apply ing a cord or bandage between the hock and stifle joint. In dogs and cats the jugular, or the internal saphena vein of the hind limb, is the vessel usually indicated in text-books, but the operation is scarcely ever performed. Arteriotomy. The opening of an artery is very seldom resorted to. The operation is carried out in the same way as phlebotomy, or the artery is exposed, divided, and, at the conclusion of the operation, ligated. Scarification. Bleeding from capillaries is effected by scarification, cupping, or the application of leeches. Leeches are little used in SCARIFICATION AND TRANSFUSION. 151 veterinary surgery. Scarification consists in making a number of comparatively shallow cuts in the tissue. It is seldom employed on account of suppuration and destruction of tissue frequently resulting. For cupping, which is also rarely resorted to, a scarifier or lancet and a cupping-glass are necessary. The scarificator (Fig. 209) consists of a metal box containing many small fleams and the mechanism for operating them. The blades can be raised or lowered by a screw, and the depth of incision regulated. The fleams, twelve to sixteen in number, are set and released in a precisely similar manner to the blades of the spring fleam previously described. The scarificator is applied to the shaven and disinfected skin, released, and applied a second time at right angles to its previous position so as to produce cross cuts. Cupping-glasses are hemispherical in shape, with edges ground to a true surface. The centre is pierced by a small hole, and carries a short hollow stem to which a strong rubber ball is fixed. The rubber ball on top of the cupping-glass is then compressed, the glass applied to the scarified area, and the ball released, causing a partial vacuum. When partially filled with blood, the glass is removed, emptied, and again applied until the necessary quantity of blood has been taken. A dressing is afterwards applied over the seat of operation. In removing blood for the preparation of protective serum ordinary methods are unsuitable, because organisms may obtain entrance to the stream of blood and the receiving vessel. The vein is therefore exposed, and a trocar provided with a rubber tube connection is inserted in it. The glass cylinder to receive the blood is closed with parchment, and covered with a movable metal cap provided with an opening. All the instruments and apparatus are, of course, most carefully sterilised. In use the parchment is pierced through the opening in the metal cap, and the rubber tube lowered into the cylinder so that the stream of blood comes as little as possible in contact with the air and forms no foam. Immediately the vessel is filled the tube is withdrawn, the cap turned round, and the opening in the paper thus covered. Transfusion. By transfusion is meant the conveyance of blood from one individual into the vessels of another. It is only employed where fatal exhaustion threatens in consequence of severe loss of Fig. 209.— Sacrificator. 152 TRANSFUSION. blood or blood poisoning, especially such as follows the respiration of carbonic acid, ordinary illuminating gas, chloroform, etc. The instruments required are a knife, forceps, scissors, a cannula, and a glass funnel with rubber tube. In mediate transfusion the healthy animal is bled into a tall vessel placed in water at blood-heat. The blood is then whipped until all fibrin is separated so that no clots may form, which might produce emboli in the vessels of the recipient. In the meantime a large vein or even an artery in the subject is opened, the cannula inserted, and some blood allowed to escape in order to expel all air from the cannula. The defibrinated blood having been filtered through fine linen is used to fill the syringe or funnel, care being again taken that no air remains in the instrument. The syringe or tube from the funnel is then connected with the cannula, and the blood passed slowly into the veins of the subject. After transfusion it sometimes happens that the body temperature falls, cyanosis and severe dyspnoea set in, followed by hemoglobinuria, or even death. The cause of this intoxication is probably the presence of fibrin ferment in the transfused blood. To prevent this the blood is often conveyed direct from blood-vessel to blood-vessel by a con- necting rubber tube. This operation is termed immediate trans- fusion. Apart from the difficulties of the process and the impossi- bility of controlling the quantity of blood introduced, there is con- siderable danger of the formation of clots. Considering its risks transfusion is nowadays practically abandoned, especially as it has been shown that the dangerous symptoms depend not so much on the want of blood as on the sinking of blood-pressure. The whole value of transfusion, therefore, lies in its providing a sufficient quantity of fluid for the heart to act upon. Similar results may be more safely obtained by subcutaneous, intra-peritoneal, or intra-venous injection of artificial serum or sterilised solution ("9 per cent.) of sodium chloride to which has been added a few drops of carbonate of potash solution. The injection of saline solution should be carried out with close attention to asepsis. The fluid should be heated to a temperature slightly above the normal body temperature of the patient ; it must be injected slowly and preferably by means of a syringe provided with a two-way stop- cock and corresponding tubes. After injecting physiological saline solution, the patient must be warmly clothed and frequently fed with highly nutritive foods. Plenty of fluid should be given ; warm milk, wine, brandy, meat extracts and eggs are all useful in restoring the condition of the blood. CAUTERISATION. 15.'{ XL— CAUTERISATION. The destruction of tissue by chemical substances or by burning is termed cauterisation. Such chemicals are comprised under the general heading of caustics, whilst the red-hot iron or other heated instrument is termed the actual cautery. Cauterisation produces a scab or scar. The dead tissue is separated by reactive inflammation, and is cast off ; healing follows by granulation. Apart from destroying diseased tissues and stimulating repair in strained or chronically inflamed tissues, cauterisation is often invoked merely to produce very active counter-irritation, sometimes to hasten cica- trisation, or to close bleeding vessels by causing contraction with thrombus formation, and thus to check hemorrhage. Chemical caustics may be divided into fluid and solid. Fluid caustics can be applied in small quantities with a brush, glass rod, Fig. 210.— Line firing iron and detachable handle. or pledget of cotton wool, etc., to the point to be cauterised, care being taken never to apply so much as to render possible the spread of the caustic beyond its intended position. If considered necessary exactly to delimit the extent of tissue to be cauterised the skin may be shaved, and a plastic containing an aperture of the desired size applied, or a mass of soft plaster may be formed into a roll and affixed to the skin around the point to be operated on, forming a little basin to receive the caustic and protect adjacent parts. Of fluid caustics may be mentioned : Sulphuric acid, which acts very rapidly and powerfully on account of the energetic way in which it removes water from living tissues and coagulates albumen. It produces a hard black scab, which remains in position a very long time. Fuming nitric acid produces a yellow scab, which is at first softer than that produced by sulphuric acid, but later becomes dry and hard. The yellow colour is due to the formation of xanthoproteic acid, a combination of nitric acid with albumen. 54 FLUID CAUSTICS. Hydrochloric, carbolic, and chromic acids act less powerfully than nitric or sulphuric acid. Among solid agents, caustic potash exercises a very marked and penetrating action. It can be applied solid or in solution. Sticks of fused caustic are to be preferred. The point is pressed on the part to be cauterised until the intended amount of action has been produced. Caustic potash, like some caustics previously men- tioned, acts by abstract- ing moisture from the tissues. It forms a g r e y i s h-y e 1 1 o w scab sometimes mixed with blood. As this scab readily breaks down and becomes fluid, the sur- rounding parts must be carefully protected from its effects. A special caustic is used in Vienna, consisting of six parts of caustic lime and five of caustic potash moistened with alcohol to form a paste, which can. then be applied to the skin to the extent required. This paste does not run or spread. Sublimate (perchloride of mercury) is also a powerful caustic. It de- stroys tissues by com- bining with their albumen, and forms a soft grey scab, which afterwards darkens and slowly separates. Sublimate is employed as a powder, paste, or solution. Sublimate collodion consists of five parts sublimate dissolved in thirty parts of collodion. Arsenious acid, or white arsenic, is usually employed in the form of paste. The action is slow, the scab firm and durable. Fig. 211. — Bud, point, line, and disc firing irons. CAUTERISATION. 155 Chloride of antimony, otherwise known as butter of antimony, has a powerful action, and produces a whitish, at first soft and afterwards hard, sharply defined scab. Chloride of zinc is an energetic caustic, and may advantageously be used by mixing one part zinc chloride with one to four parts of flour, water being added to form a paste. Nitrate of silver and sulphate of copper are perhaps the caustics most generally employed. Nitrate of silver, or lunar caustic, has only a superficial action. The scab is at first white and soft, later becoming dark under the action of light. Sulphate of copper is cheaper than lunar caustic, and is sometimes used to destroy exuberant granulations. The longer the caustic remains in contact with the tissues the more extended is its action, as it continues to spread from the fresh scab. Where the action proves insufficient it may be renewed as soon as the scab is shed. For destroying new growths, caustics in the form of pastilles or rods are sometimes used, an incision being made in the growth for their introduction. In other cases solutions are injected. These methods, however, are not to be commended because the range of action of the caustic cannot be controlled. Sometimes a portion of the growth is left, necessitating a second operation ; sometimes the action of the caustic extends to healthy tissue with unfortunate results. The caustics, and especially the more active, produce severe and continued pain during their action. The actual Cautery— Firing. Although less used than formerly firing continues very popular, and is employed with success in many conditions which have resisted all other treatment. Without doubt it gives lively pain, necessitates a certain period of rest, and some- times leaves indelible marks, but these drawbacks are more than counterbalanced by its many advantages. Among the indications for the employment of the actual cautery, the most frequent are chronic affections of tendons, tendon sheaths, ligaments, bones, synovitis, sprains, luxations, exostoses, enlarged joints, and necrosis. Tt is also used to divide tissues, to remove chronic lymphatic thickening, to stimulate healing of fistula?, indolent ulcers, and poisoned wounds, in the treatment of tumours, and to check haemorrhage. Distinctions have been made between mediate and immediate, superficial and deep or penetrating firing. In mediate cauterisation, a glowing iron is brought close to the spot to be acted on so that the parts are merely heated by radiation ; in immediate cauterisation, the instrument is brought in actual contact with the tissues. Surface firing, i.e., firing extended areas all over, 156 LINEAE FIRING. and the application of burning pastilles (moxas) are now entirely abandoned. The methods at present used are (I) superficial firing in the form of points or lines, the instrument not passing deeper than the Fig. 212. Needle tirin with interchangeable needles epidermis itself ; (2) deep firing in fine points, where the skin is penetrated at one or a number of spots ; (3) needle firing, in which the instrument penetrates the muscle, tendon, ligament, bone or synovial sac ; (4) subcutaneous firing, practised after the skin has been divided with a knife. FlO. 213. — Degive's needle firing apparatus packed in box. The instruments used for line firing are provided with heads resembling wedges or triangular prisms. The cauterising margin should be slightly convex, smooth throughout and rounded at the angles ; a slight curve in the stem is thought by some to be advantageous. With instruments of this form it is easy to follow APPLICATIONS OF F1RINO. 157 the inequalities of the surface and to ensure each part being subjected to the same action. Fig. 210 shows the ordinary form of the English firing iron. It is suitable for most purposes. The length of stem varies according to whether it is intended for use on the animal in a standing position or when cast. Messrs. Arnold make these instru- ments in many forms, all fitting one handle. The head of the point or bud-firing iron consists of a more or less elongated cone ; for deep firing it is drawn to a much finer point. Needle firing is performed with very fine points, capable of penetrating the tissues deeply. It was formerly the custom to use stout needles, about four inches in length, which were brought to a red heat in a charcoal furnace, Fig. 214. — Degive's apparatus ready for action. The reservoir in the handle is filled with sponge saturated with benzine vapour. The bellows pumps air through this reservoir. The stream of benzine-laden air is mixed with a stream of pure air controlled by the two-way tap at the base of the handle, and burns with an intensely hot blue flame in the hood. The tap at the base of the handle regulates the size of the name, and therefore the temperature. grasped with pincers or forceps and plunged into the tissues. These were replaced by instruments consisting of a heavy cone-shaped head, with a central aperture through which a suitable needle could be passed. The head was first heated, and when red, the needle was dropped into position. In the greater number of such instruments, however, the needles become cold very rapidly, and the large head cauterises the skin around the perforation. To protect the skin it becomes necessary to place a small disc of iron with a central aperture over the point of operation. Several instruments with movable needles have been invented. Degive's (Figs. 213 and 214) is probably the best, though similar instruments have been produced by Bourget and De Place. It consists of a handle, which also acts 1 58 CAUTERIES. as a benzine reservoir and saturator, carrying at its extremity a small iron box with a conical base, through which is drilled a hole for the passage of the needle. This latter is held on a movable arm, which permits it either to be protruded through the base of the box or to be retracted within the latter by a spring. A bellows and benzole container supply the heat, the flame playing within the cavity of the iron box. Each time a puncture is to be made the red-hot needle is protruded from the point of the box and thrust into the tissues. The action of the spring automatically returns it to the interior of the box, where the flame almost immediately renders it hot again. The two following firing instruments were described by the writer some years ago (see " Veterinarian," February, 1898). They have been used by him in his practice for many years, and both have been found very satisfactory. The first is Graillot's Zoo-cautery (Fig. 215). It is an adaptation of Paquelin's, which depends for its action on the peculiar property possessed by metallic platinum, and in an even higher degree by platinum in a finely divided state (platinum- black), of bringing about chemical combination between oxygen and hydrogen gases, or between oxygen and certain hydrocarbon vapours, without the intervention of a flame. The zoo-cautery consists, as shown by the annexed rough sketch, of three principal parts, viz. the handle, forming a benzoline reservoir, the stem, and the head. The handle (b) is formed of thin metal, spun on a lathe and corrugated, both to afford a better grip and to increase the surface from which evaporation takes place. Its interior is packed with fragments of sponge saturated with benzoline, and through the centre passes a small tube, which conveys a portion of the air, pumped into the apparatus directly towards the stem, without passing through the sponge. At the extreme end of the handle is a nipple, over which is slipped the india-rubber tube of the bellows, and a little two-way stopcock (a), which when turned in a line with the handle allows air to pass freely both through the small (direct) tube mentioned, and also through the mass of sponge in- the handle ; but when turned at an angle gradually shuts off the stream from the sponge-packed part until at last (at right angles) it admits air alone through the direct tube. By examining the top of the handle before screwing in the stem the small direct air-tube will be seen projecting upwards through the mass of sponge. The stem (c) is merely a strong metallic tube supporting the head, and conveying to it the mixed air and benzoline vapour delivered degive's and graillot's cauteries. 159 from the handle. At its upper part is a clamping nut, by means of which the head can be set in a line with, or at any angle to, the stem. The head consists of a hollow nickel shell carrying at its extremity the cauter- ising surface or point, made of platinum- iridium alloy, and lined within by frag- ments of fine platinum gauze to assist the combustion of the vapours. Special attention is directed to the screw (d) shown on each of the heads, as it plays an important part in the working of the apparatus. To start the cautery in action, the stem is first unscrewed, and benzoline poured into the handle from the upper end until it overflows. The handle is then inverted, and all excess of benzoline allowed to flow away, leaving the sponge saturated. The parts are then screwed together, the bellows affixed and started, the little two-way stopcock (a) at the bottom turned nearly at right angles, the small screw (d) in the head opened as far as possible, and a light applied to the holes shown in the head. If all is acting properly, a strong bluish flame will be seen within the head, and a rather loud hissing sound will be heard. If not, the bottom stopcock is turned one way or the other, so as to alter the pro- portions of air and benzoline vapour passing to the head, until the flame appears and burns steadily. In a minute or two the entire head will become strongly heated, and if the top screw (in the head) be then turned home, the blue flame will disappear, the hissing noise will cease, and the point of the cautery, previously quite dull, will sud- denly begin to glow, and soon attain a bright reddish-white heat. The reason of this is that the direct flame is extinguished, and the vapours are caused to burn within The zoo-cauterv. 100 DECHERY S CAUTERY. the platinum- point or head. The instrument is now ready for use, and will continue acting for twenty minutes to half an hour by simply working the bellows. Should the heat decline, a slight turn of the lower stop-cock will admit more benzoline vapour and restore the required temperature. If employed in the open air some precaution is required when starting to shield it from draughts. A point of con-, siderable importance is to obtain the right kind of benzoline ; the com- mon benzoline sold in oil-shops for use in cabmen's lamps or in the little cheap night lamps seems to answer best. The second instrument shown i (Fig. 210) is quite different in principle from that of Paquelin, and has the great advantage of being automatic in action when once started, and of requiring no bellows. Every one has probably seen the flaring, roaring lamps used in carrying on railway works, large building operations, etc., at night ; the roar- ing noise and the intense light dis- tinguish them from others. Dechery's > cautery is a modified reproduction of one of these. It may be divided into reservoir (aa), vapour-chamber (b), and burner. The illustration shows these, the essential portions of the interior being indicated by dotted lines. To resist the considerable pres- sure at which it works, the instru- ment is strongly made of nickel led brass. The reservoir is shut off from the vapourising chamber by a conical valve, worked by means of a long spindle (c) carrying at its extreme end a milled nut. The vaporising chamber consists of a small Fig. 216. lechery's automatic CAUTERY. 161 brass casting, hollow in the centre, and presenting two apertures — that at the bottom, through which the benzol enters, being closed by the conical end of the spindle ; and a second, extremely small one at the side, through which the vapour issues at high pressure. As will be noted (see Fig. 216), this minute stream of high-pressure benzol vapour then rushes through a rather wide tube, inducing in its passage a smart current of air, with which it becomes intimately mixed, and finally burns in the head with a bright blue, smokeless, but intensely hot flame. To start the apparatus the large bottom nut is unscrewed, and the reservoir filled with carefully filtered benzol. (It is important to filter the benzol carefully, as the smallest speck of foreign matter may choke the minute orifice in the vaporising chamber from which the vapour issues.) The parts are then screwed together, the valve spindle turned home, and the head heated in a spirit-lamp flame for two or three minutes. This warms the head and vaporising chamber, and prepares the apparatus for starting. As, however, there is at first no positive pressure within the apparatus, the benzoline would not flow into the vaporising chamber, and it therefore becomes necessary to heat the stem, so as to cause the benzoline to expand and to flow out when the valve is opened. The flame is therefore advanced a little, and allowed to play round the top of the stem for a minute or two, when, on opening the valve by turning the milled head with the fingers, a few drops of benzoline are injected into the heated vaporising chamber, are converted into gas, rush out into the head, become mixed with air, and burn into the outer part of the head, as above described. If the apparatus has been sufficiently warmed at the outset it now becomes self-acting, the heat of com- bustion being conducted to the vapour-chamber and the stem to a sufficient degree to promptly convert the benzol into gas as it issues from the reservoir, and to keep the benzol in the reservoir itself nearly at boiling-point. It may be imagined, however, that the pressure in the apparatus would become dangerous and involve an explosion. Two safeguards are provided against this. Firstly, the apparatus is very strong ; and secondly, an undue pressure in it would force benzoline outwards in such quantity as to produce large white flames, and thus give timely notice of danger. In practice the writer has found the apparatus remarkably steady and reliable. The firing points and edges are easily heated to a bright cherry red, and the apparatus works without any regulating for twenty minutes to half an hour, when a turn of the milled head will enable one to i62 HEATING CAUTERIES. continue for another quarter of an hour, a sufficient period to finish an ordinary operation. As the whole apparatus would otherwise become unpleasantly warm, the main body of the reservoir is covered with a tube of insulating material, — " vulcanised fibre." The fact that the expen- sive platinum heads and points are entirely dispensed with permits of the apparatus being sold at a very reasonable sum. For heating the ordinary iron a forge or small stove is usually employed. Charcoal or coke is preferable to coal. Within recent years, however, advantage has been taken of the numerous automatic lamps, burning petroleum spirit or benzole, to produce a convenient and easily transported stove. In these lamps the pressure produced within the body of the lamp by warming the fluid, causes a small quantity to mount through a capillary tube into a chamber sur- rounding the flame, which chamber is therefore always at a high temperature. Arrived here the liquid is rapidly transformed into gas, and escaping through a small hole, emerges in the form of a powerful jet which sucks air through orifices surrounding it, and when ignited burns with a very intense flame. By adapting to such a lamp a suitable hood for receiving the heads of the firing irons an excellent portable furnace is produced. A very good form of automatic petroleum furnace is that shown in Fig. 217. The reservoir (a) contains ordinary petroleum oil, with which it is filled through the plug (6). To set the apparatus in action, the small air-pump (c) is worked for a minute or two, until the air pressure in the reservoir is sufficient to force the oil up to the burner (/). A little methylated spirit is then poured into the ring at the base of the burner and ignited, thus heating the burner. On then cautiously relaxing the screw (0), a fine stream of petroleum flows into the burner, becomes vaporised, and issues as a powerful jet from a small orifice at the base of the tube (/), shown as a dotted line. This jet aspirates strong currents of air through the holes in the burner, mixes with this air, and burns with an intensely hot blue flame within the hood (g). Whatever the method of firing adopted, certain general principles must be observed. The preparation of the animal is important. If casting is necessary it should preferably be done on an empty stomach ; if the animal is very vigorous and plethoric, the food allowance should be reduced during the previous days, and laxatives must be administered. The point of operation must be thoroughly cleansed, and the hair cut either with a machine or with scissors, but in deep firing, involving synovial membranes, antiseptic pre- ANTISEPTIC FIRING. 163 cautions are necessary. The cleaner the skin the less the danger of after-infection. For this reason, when firing in deep points, the writer usually applies over the whole area of operation a dressing wetted with 5 per cent, carbolic solution, which is allowed to remain in position for twenty -four hours, and to become dry by evaporation. It is removed immediately before operation, and is afterwards replaced by a dry dressing of boric acid and surgical cotton wool supported by a bandage. Where the points are less deeply introduced it suffices to smear the parts freely with boro-glyceride after operation, omitting the cotton wool, etc. No blister is used. In applying the iron to certain regions where the skin is very mobile, it is well, if casting is necessary, to mark the outlines of the surfaces to be fired before- hand. Quiet horses are usually fired in a standing position, a twitch being applied to the nose, and the foot lifted to prevent accident. In more extensive operations the parts may be rendered insensitive by subcu- taneous injection of cocaine, or by the application of an elastic bandage or cord. The most convenient appara- tus for controlling animals when being fired is undoubtedly the operating table previously de- scribed. Firing, however, is often necessary when no such table is at hand and the animal must be put down. In operating on the external surface of a limb, the horse is cast on the opposite side. If the application is made around a joint, the animal should be cast on the diseased side and the inner face of the limb first operated on. In firing two limbs, the external surface of the one limb and the internal of the other are first completed, and when turning the animal over provision must be made against the cauterised surfaces being soiled or bruised. Various manoeuvres are sometimes necessary. As a rule the limb to be fired is left in the hobbles, while the opposite limb is Fig. 217. — Automatic petroleum furnace and protecting hood for heating firing irons. Hi4 LINEAR FIRING. released and carried either backward or forward. When the pastern or coronet is to be fired, the two limbs can be fastened together above the knee or hock respectively, the diseased limb being released from the hobble and drawn forward or backward by an assistant using a broad strip of webbing. In line firing, the important point is to trace equally spaced straight lines, extending beyond the diseased region. Converging lines should never cross or unite, the points of crossing being very liable to slough (see Fig. 218). The spaces between the lines vary according to the thickness of the skin and the extent of the cauterised region. Closely placed superficial lines are preferable to others more distant and more deeply penetrating. As a rule a space from three eighths to three fourths of an inch should divide the lines. In France the custom is first to lightly mark out the design, and after- wards to pass the cautery over the lines a number of times. The iron is used at a dull or bright red, the latter being the maximum temperature allowed, and is passed slowly along v \ ^ the marked-out design without pressure, the \ . ^ blade being always kept perpendicular to s \. ^ the surface. The iron should never be passed "\ ^ twice in immediate succession along the same line, and if the French method be adopted, Fig. 218.— Pattern for ^ e \j nes must be retraced in regular order, line firing. The lines .. . , , . do not meet. otherwise sloughing is apt to occur. The operator judges when the cauterising action is sufficient by the appearance of the base of the lines, the ex- udation which has occurred, the infiltration of the skin, and the degree of separation shown by the epidermis. Judged by these standards, three degrees of cauterisation may be distinguished. In the first the lines are shallow and contain a few little drops of serosity. Their base is of a golden yellow, the skin is little infiltrated, and the epidermis is still adherent. In the second the lines are deeper, their base yellowish brown, exudation is more marked, and the epidermis is loosened. In the third the epidermis is almost cut through, the margins of the lines tend to gape and produce irregular edges, the serous dis- charge from their base is abundant, and the skin is often covered with vesicles. In the French system the iron is heated to a cherry red, and is passed along each line five or six times in light firing, eight to ten in ordinary firing, and twelve to fifteen in severe firing. It is clear, however, that the number of passages must vary with the weight and temperature of the cautery, the judgment of the operator, and the thickness of the skin. LINE AND PUNCTURE FIRING. 165 Superficial puncture or bud firing can often be performed in the standing position. The points should form a regular figure, those of one line corresponding to those of others adjacent. As a rule the points are separated by intervals of three eighths to an inch, though they may be massed a little more closely where the most intense action is required. Here again the French prefer to apply the iron a number of times to the spots seriatim. The completion of the process is judged of by the same indications as in line firing. In England, however, it is unusual to apply the iron more than once, or at the most twice, a method which appears to be perfectly suc- cessful, and when combined with the after-application of a blister, to have the advantage of leaving less mark than the French method. In deep point or needle firing the cautery passes completely through the skin and subcutaneous connective tissue into the diseased part. The points must be disposed regularly, and at equal distances, though they may be placed rather more closely together than when firing the skin alone. With gentle pressure the cautery rapidly perforates the skin. This method has the advantage of being easy and rapid to carry out, and of producing a more intense and deeper action than that previously considered. The iron should never be applied more than twice. A light blister may be applied a few days after operation. Until comparatively recent times the danger of penetrating synovial sheaths, etc., was regarded as excessive, and although a few practi- tioners like Basch, Fischer, and Robertson recommended puncture with fine pointed irons, the method was never extensively accepted, and when practised not infrequently led to disaster. In 1867 Bianci recommended puncture of dropsical synovial sheaths with the red- hot needle, a system which, after long discussion and some modifica- tion, is now becoming more and more popular. Even if carefully practised it is not without danger, especially for articular cavities, but considering the intensity of its action and its therapeutic value it constitutes a great advance on older methods. The point, however, must be extremely fine, those usually employed not exceeding one twenty-fourth to one sixteenth of an inch in thickness. When of iron these are difficult to make and to keep in order ; platinum points like those supplied with the zoo-cautery are preferable. The punctures are best made in a regular design at intervals of about an inch. The method of procedure is important : the needle, at a red heat, is sharply thrust to the required depth, and immediately withdrawn. There is no disadvantage in passing the needle more than once into fibrous or osseous tissues, — indeed, this is necessary to produce intense 166 TREATMENT AFTER FIRING. effects ; but in dealing with synovial membranes the passage of even a fine needle more than once is dangerous. * On the other hand, no bad results need be feared from penetrating a synovial sheath, provided the puncture be made with a single application. The minute channels are aseptic when made with a red-hot instrument, and provided the needle be sufficiently fine, and the operation completed with one movement, they remain so. It is not necessary, however, in dealing with dropsical synovial sheaths that all the points should penetrate the sac ; as a rule one actual puncture is sufficient. In other tissues two or three punctures may be made. In certain cases the operation may be followed by the application of a blister. The emollient dressings formerly employed after firing appear in the light of later experience to be contra-indicated, as they favour suppuration, retard healing, and tend to increase the area of the wounds and of the subsequent cicatrices. They should certainly not be employed immediately after operation. When the inflamma- tion of the skin after firing is intense, antiseptic lotions or powders may be employed. If, on the other hand, the reaction is insufficient, a blister of biniodide of mercury, or cantharides may be applied immediately or within a day or two after firing. In thoroughbreds and other horses with a fine skin the application of a blister to the fired surface should be deferred until the wounds made by the cautery have healed and the local swelling has disappeared. For these animals the blister should be about half the strength of that applied to draught horses. The results of firing vary greatly according to the method employed. A day after superficial firing considerable swelling and more or less abundant exudation especially from the lines or points, will be observed. The liquid dries, forming yellowish-grey crusts, covering the whole region. The horse has pain in moving, shows marked lameness and intense local irritation . As long as these continue the horse must be closely watched, and care taken to prevent the parts being bitten, scratched or rubbed against neighbouring objects. The best method is to tie the animal to the pillar reins, or to a ring above the manger, apply a cradle to the neck, and dust the fired surface with a mixture of boric acid, zinc oxide and kaolin. The crusts become loose towards the eighth, tenth, or fifteenth day ; to assist separation the parts may be bathed with warm water, or preferably dressed with an antiseptic ointment. If the skin tends to crack, the parts are covered with boric vaseline or glycerine. At a later stage the scabs produced by the cautery disappear. When extending deeply and implicating the TREATMENT AFTER FIRING. 167 whole thickness of the skin they are sometimes very adherent, and only separate after a suppurative inflammation, leaving exuberant granulations, which are followed by indelible scars, the covering of hair never being restored. While these processes are going on at the surface the subcutaneous tissues have become hypersemic and inflamed, infiltrated with an abundant exudate, and the seat of active cellular proliferation. This condition is later followed by resorption, consolidation, and com- pression, results to which the beneficial action of firing is often attributed. The effects of deep point firing are still more marked. The limb often becomes greatly enlarged, although a free serous discharge occurs through the skin. The small, closely-packed cicatrices in the skin and cellular tissue resulting from such firing form a kind of permanent compress which is much superior to bandages. It is certain that the retraction of these islands of new tissue exerts on the diseased part an active compression resembling that produced by an elastic bandage. The treatment of the patient differs in no essential respect from that required after superficial firing. The symptoms shown after deep needle firing depend on the depth of penetration and the nature of the tissues involved. Active inflam- mation always results in the region cauterised. The limb becomes greatly swollen, sometimes very hot and painful, while the animal shows more or less marked fever. Moreover, when a synovial sac has been opened synovia is discharged, sometimes in large quantities, forming a yellowish-grey albuminous layer, which may even flow downwards over the foot or reach the ground. At the end of two or three days this synovial discharge hardens, the apertures become obliterated, and the discharge ceases. The crusts separate during the second week ; the scars begin to disappear towards the twentieth day, leaving in their place little reddish cicatrices. Swelling of the parts sometimes persists for a long time, but can be diminished by exercise and massage. The hair rapidly grows again, and almost entirely masks the little smooth cicatrices left by the cautery. This is one of the chief advantages of the method. Whatever the degree of firing or the mode employed, a certain period of rest is requisite to permit of the gradual subsidence of inflammation and its effects. As a rule, after the lapse of the second or third week following operation it is well to walk the patient daily for ten to twenty minutes. When the fired surface has recovered from the action of the blister, the animal may be sent to grass, or 168 SUBCUTANEOUS CAUTERISATION. rested in a strawyard for two or three months. In injuries to the tendons, in spavin lameness, and some other conditions such rest is absolutely essential. The operation may be complicated in various ways. Thus the skin may be divided and a gaping wound produced ; capillary haemorrhage may result, or the fired surfaces may be torn. Such results may, however, be avoided by reasonable care. Loss of skin and the formation of large cicatrices following too severe a use of the iron are more serious. When such results threaten means must at once be taken to prevent sloughing. The frequent application of the cold spray is one of the most common methods ; if conjoined with an antiseptic lotion it is more useful, it cleanses the parts, and removes the irritating exudate which aggravates the inflammatory symptoms. Lotions, astringent compresses moistened with weak acetate of lead, or alum solution, and a paste, made with calamine and boiled water, have also been recommended. Lukewarm anti- septic baths followed by dusting with iodoform or a mixture of iodo- form and tannin are preferable. Nocard highly recommends spraying with an ethereal solution of iodoform. He says that it abolishes suppuration, and checks the microbic infection of the wounds resulting from the removal of the scabs. Haemorrhage resulting from puncture of a vein or arteriole by the needle is without danger. It either ceases spontaneously, or can be stopped by a tampon of wadding, or by applying a compress powdered with iodoform. Subcutaneous cauterisation, recommended in Italy, appears to present no marked advantages, and may be dismissed here with the statement that the skin is first divided, the edges held apart, and the globular-headed iron applied directly to the deep-seated structures thus exposed. In times past it was not unusual to fire sound horses with the idea of preventing the formation of ring-bones, spavins, etc. Needless to say, such a course is not only inhuman but absolutely useless. XII. SETONING. Formerly setons were frequently used as counter-irritants in the treatment of muscular atrophy, lameness of the hip or shoulder, spavin, and navicular disease. In current practice setons are mainly employed to establish drainage of abscess cavities, sinuses, and lacerated wounds in process of healing. As, however, many practitioners have faith in the value of setoning in the treatment SETONINU. L69 of chronic lameness and some other conditions, a diagram is furnished below showing the various positions in which setons may be introduced. Setons are inserted with a special needle (Fig. 220), from eight to sixteen inches in length, and usually made of steel or soft iron. The point, sharp or blunt, is spatulate and of steel, the body is usually flattened and often divided into two parts, which can be screwed together. The eye is sometimes at one end, some- times at the other. For the purpose of passing frog setons Sewell invented a special needle (Fig. 220a). For operating on hsematomata, etc., the needle shown in Fig. 220b is used. It consists of two cylindrical portions (about three sixteenths of an inch in thickness), Fkj. 219. -Schema showing positions in which setons may be inserted. which can be screwed together. The point resembles a three-sided pyramid. Should the animal prove very troublesome it may require to be cast before a seton can be inserted, but as a rule it is sufficient to apply a twitch and lift one of the fore-feet. Generally, it is best to pass the needle from below upwards, as should the animal struggle it is more easily withdrawn, while it is less likely to go astray. Should it be inserted in the opposite direction and an error be made necessitating change of direction, a pocket is left in which pus may accumulate. Views differ as to the depth to which setons should be inserted. Some prefer the subcutaneous tissue, others penetrate beneath the panniculus. The latter method, however, is sometimes followed by 170 SETON1NG. troublesome extension of the suppurative process, and is not to be recommended. Having selected the lowest point, the skin is raised in a fold and either divided with rowelling scissors (Fig. 221) or with a knife. The Fig. 220.— Seton needle with eye in head and also at base. Fig. 221. — Rowelling scissors, for making the preparatory incision when inserting seton. Fig. 220a. point of the needle is then introduced, with its flat side towards the skin, and the needle thrust forward, its course being carefully noted, and if necessary controlled by the fingers of the left hand. The needle used in France possesses a sharp point, and therefore readily penetrates the skin at the end of its course ; but with the common English needle it is necessary to make an incision for exit. The SETONING. 171 point of the needle is then grasped with fingers or forceps and with- drawn through the upper orifice, bringing with it the tape with which it has been threaded. If, however, the eye is in the point of the needle the tape is not inserted until the eye appears through the upper wound. The tape is then passed and the needle with- drawn, leaving the tape in position. The tape, which must be at least twice as long as the seton track, is secured by firmly tying the ends together or by attaching each end to a transverse piece of rubber tube. The disadvantage of uniting the ends consists in the danger of the loop so formed catching on a hook or other object or being grasped in the horse's teeth, and the seton being torn out. To prevent this the horse should be tied up or a side-stick applied. In dogs a muzzle must be put on. To increase the action the seton is smeared with an irritant, and is daily moved to and fro. As soon as pus forms, free drainage should be secured by fomenting the orifices daily and gently stroking the channel from above downwards. The seton may be left in position from eight to twenty-one days. To remove it the upper end is snipped off with scissors and the tape drawn downwards. If left too long in position ulceration and sloughing of the skin over the seton may be produced. Inserting a frog seton demands certain special precautions. The horn around the point of the frog having been thoroughly thinned, an incision is made above the bulbs of the heel, and the special needle, with its convex side towards the tendons, is thrust down- wards through the plantar cushion towards the point of the frog, the foot meanwhile being extended as far as possible. The needle should appear near the point of the frog. The ends of the tape are knotted together and a dressing applied. In passing setons, blood vessels may be wounded, but as only small twigs are usually affected no special precautions are called for. Where nerves are injured paralysis may result, and in some cases tendon sheaths and joints have been opened. The passage of a seton under fascia?, or the panniculus may be followed by extensive suppuration, with abscess formation at some distance from the seton. Occasionally, and especially during summer, infection of the seton track occurs with extensive inflammatory oedema — which may lead to a fatal result. After removal of the seton, the wounds may granulate excessively, producing considerable deformity of the part ; in that event the wounds should be treated by compression, dried alum, or the actual cautery. 172 INOCULATION. XIII.— INOCULATION. By inoculation is meant the intentional conveyance of infectious material to a healthy subject. A wider meaning is sometimes attached to the term, causing it to extend to the products of micro- organisms such as antitetanic and antidiphtheritic sera, mallein, etc. Inoculation is a most important process in studying the life history of bacteria, their nature, virulence, mode of action, etc. Animals, again, are inoculated to protect them against certain diseases, like black-quarter, anthrax, and swine erysipelas (rouget du pore), to pro- duce new (modified) infective material (vaccine), and finally, though not very often, to shorten the duration of epizootic disease. Various forms of needle have been used for inoculations. The oldest is Sick's (Fig. 222). A furrow in the middle of the head holds the infective material. Sticker employed a special needle (Fig. 224) for pleuro- pneumonia inoculations. The needle was thrust under the skin, and the virus injected by pressing on the button at the side of the handle. Fig. 223 represents Pessina's needle. In use the furrow is filled with virus, the needle thrust into or under the skin, revolved and with- drawn, leaving the infective material within the wound. At present, sterilisable syringes are almost universally employed for protective inoculation, as well as for the injection of mallein and tuberculin for diagnostic purposes ; an operation which is closely akin to inoculation, and is carried out in a similar way. As a rule the stem of the piston carries a movable stop which can be fixed at a prearranged point, allowing only the exact amount of material Fig. 223. Fig. 224. INOCULATING INSTRUMENTS. 173 to be injected at each operation. Such syringes are now made with asbestos or metal plungers, and can be taken to pieces, or are of such a nature as not to be injured by boiling or otherwise sterilising. Before making the injection the point of operation should be shaved and thoroughly disinfected. Care must be taken, except in Fin. 22. r >. — Sterilisable syringe ; ready for use. I-I»_ Fig. 226. — Sterilisable syringe ; dismounted, endermic inoculation, that the fluid really penetrates beneath the skin and not into it or into the muscular tissue, as often happens. Neglect of these precautions, or failure thoroughly to sterilise the instruments, explains most of the cases of abscess formation, and other exceptional complications after inoculation. The best plan is to raise a fold of skin with the left thumb and fore-finger and rapidly thrust the needle through the skin in the length of the fold. The fluid is spread over a larger surface by gently manipulating the parts after removing the needle. After injection the syringe and needle must be thoroughly washed and sterilised. As a rule no special restraint is needed, as the pain is very trifling. In large vaccine institutes the smaller animals are usually secured on movable operating tables. Fig. 227. — Roux's sterilisable syringe without piston. 174 INTRAVENOUS, SUBCUTANEOUS, AND OTHER INJECTIONS. XIV.— THE INJECTION OF MEDICINES INTO THE BLOOD-STREAM, SUBCUTANEOUS TISSUE, TRACHEA, PHARYNX, LARYNX, OR PARENCHYMA OF ORGANS OR TISSUES. (a) Intravenous injection. In former times bleeding was often a preliminary to intravenous injection of medicines. In horses, for instance, the jugular vein was opened with the fleam, and the medicine injected by means of a funnel and tube. Apart from the danger of thus introducing air into the vein phlebitis often followed. At the present time a fine trocar and cannula, or a syringe with a hollow needle is used for intravenous injection. In horses and cattle the jugular vein, and in dogs the saphena vein are the vessels selected for the introduction of remedies into the circulation. The number of materials fitted for intravenous infection is limited to a few alkaloids, antitoxins, normal saline solution ("9 per cent.), barium chloride, silver colloid, chloral hydrate, etc. The intravenous method has the advantage of producing immediate effects, while subcutaneous injections require at least four or five minutes, but this advantage is more than offset by the time required to prepare the solution and the seat of operation previous to intravenous injection. The fluid for injection must be diluted, non-irritant, and aseptic. Injection with the ordinary syringe is carried out as follows : — After disinfecting the skin at the seat of injection, the operator grasps the shaft of the hollow needle between the index and middle fingers of the right hand, the thumb resting on the broad expanded base. The right jugular vein is compressed with the thumb of the left hand and the needle thrust obliquely downwards through the skin covering the most prominent part of the swollen vein at the spot usually chosen for bleeding. As the animal is often restless at this stage the right hand is simply pressed against the neck without for the moment attempting to introduce the needle further. As soon as it becomes quiet the needle is sharply thrust a little further in the same direction. If the attempt has been successful blood will flow from the open end of the needle when the thumb is removed, showing that it has entered the vessel ; otherwise another trial must be made. The needle is introduced as close as possible to the point compressed by the thumb, as the vein is partially fixed there and is less likely to evade the needle. Once introduced into the vein the needle should be moved as little as possible to prevent injuring the intima. Having satisfied himself that the syringe contains no air, the operator then affixes it to the needle and steadily injects the contained fluid into the vein. HYPODERMIC AND INTRATRACHEAL INJECTIONS. 75 The double-acting syringe is employed in a similar way. One nozzle is connected by a rubber tube with the needle inserted in the vein, the other by a similar tube with the vessel containing the injection fluid. After injecting the contents of the syringe into the vein the two-way tap is turned and the barrel of the syringe again filled by drawing back the piston. By returning the tap to its original position and once more pressing down the piston a second quantity is injected ; the process can be repeated as often as desired. One of the drawbacks of intravenous in- jection is the tendency to thrombosis of the vein in consequence of injury to the tunica intima by the needle. This danger, however, as well as that of the entrance of air, can be avoided by skilful manipulation. By proper care in choosing the drug and carrying out the above manipulation bad results are avoided. (b) In subcutaneous or hypodermic injection, which has largely replaced the above method, the drug is injected by means of a syringe and hollow needle into the loose connective tissue beneath the skin. A graduated syringe holding about 2 to 4 fluid drachms is used and the injection made at a spot clear of the harness and where the skin is freely movable, i.e. where sub- cutaneous tissue is abundant. The side of the neck, breast, behind the elbow, and flank are convenient positions. By this method various alkaloids, sera, vac- cines, mallein and tuberculin are administered. Hypodermic solutions should be sterile and non- irritant. The syringe and needle should be thoroughly clean and sterilised by boiling or by washing with 5 per cent, carbolic solution. This precaution is doubly necessary when the syringe has been pre- viously used for annuals suffering from contagious disease. The seat of operation should always be disinfected before injection. Raising a fold of skin with the thumb and index finger of the left hand the operator passes the needle along the fold or at right angles to it into the subcutaneous tissue. When, as occasionally happens, a blood-vessel is punctured, as shown by the escape of a few drops of blood, the needle should be partly withdrawn, and if the bleeding Fig. 228.— Double- acting syringe. 176 TRANSVERSE SECTION OP THE HORSe's NECK dorsal panmaihis jugular veiri N j I erne thyreoid. Mm sterno-hyoida Z-'?ntral Fio. 229. — Transverse section of the neck at right angles to its long diameter. The section passes through the third cervical vertebra, a, Portion of the head of the fourth cervical vertebra ; b b, Vagus and sympathetic nerves ; c c, Re- current nerves ; d d, Dorsal branches of spinal accessory nerve ; e e, Inter- transversales colli muscles ; / /, Muscular twigs of the cervical nerves ; g g. Tracheal lymph duct ; i, k, Transverse processes of cervical vertebra ; I, Inter- vertebral disc of cartilage ; m m, Vertebral artery and vein ; «, Lymphatic nerve twig ; o, Spinal cord ; p, Membranes of the cord ; q, Vessels of the cord, r, Carotid artery. (After Ellenberger and Baum). INTRATRACHEAL INJECTIONS. 177 ceases the syringe may then be fitted to the needle, the fluid slowly injected, and the needle withdrawn. By gently stroking the skin, the injection is dispersed over a larger area in order to promote rapid absorption. (c) Intratracheal injection is practised for the purpose of treating diseases of the upper air-passages like chronic laryngeal or tracheal catarrh, to kill parasites present in the trachea and bronchi, and as a means of combating certain general disorders like purpura hemorrhagica and hemoglobinuria. As absorption occurs very rapidly from the tracheal and bronchial mucous membrane this system of medication has a rational basis, but, as a rule, more convenient and less dangerous methods deserve preference. From the experiments made it has become clear that the tracheal mucous membrane is far less sensitive than was formerly imagined, and that irritants like tinctures and oil of turpentine are really very well borne. As, however, the tracheal mucous membrane cannot be disinfected the small punctured wound may not heal aseptically, and although in healthy animals there is little danger, yet, should inflammatory action set in, as may readily occur in purpura, serious consequences may follow. Recent experience shows that necrosis of the tracheal mucous membrane, and even of the lungs, sometimes occurs. The needle must be cautiously inserted, and as it is sometimes subject to considerable stress it should be stout in order to avoid breakage. In the event of this occurring the broken fragment must at once be grasped with forceps, or, if it be invisible, a cutaneous incision must be made in order to detect and remove it. Intratracheal injections may be made with an ordinary hypo- dermic syringe provided with a stout needle, with a large Pravaz syringe, or with Dieckerhoff's syringe, which is used in conjunction with a special trocar and cannula. The animal's head is raised, and the operator, stretching the skin covering the front of the trachea with the fingers of the left hand, thrusts the needle or trocar through the space between two tracheal rings. Removing the stilette he inserts the nozzle of the ready-filled syringe in the mouth of the cannula, and slowly injects the contents into the trachea. Dieckerhoff also recommends intralaryngeal and intrapharyngeal injections. The method is similar to that above described. A curved needle, with its convexity directed upwards, is passed between the cricoid cartilage and the first ring of the trachea, traversing the crico-tracheal ligament, and fluid is thus injected into the larynx or pharynx. In chronic laryngitis Dieckerhoff 178 PARENCHYMATOUS INJECTIONS — CASTRATION. recommends subnitrate of bismuth or 1 per cent, iodine solution (Lugol's solution) repeated every few days. (d) Parenchymatous injection consists in introducing solutions of drugs into the parenchyma of organs, like the thyroid or lymphatic glands, or into muscles or pathological new growths. The active agents are thus brought into immediate contact with the affected tissues. In veterinary surgery actinomycotic growths are the commonest objects of such treatment, though tumours and the swellings of goitre have also been injected, but with varying results. Solutions of acetic, carbolic, or lactic acid, iodine, zinc chloride, strychnine, nuclein, papain, etc., have all been used for parenchymatous injection. In the hands of several operators iodine and papain have given good results when employed against soft new growths and goitre. A rather stout needle is inserted — -if possible, into the centre of the organ or growth (sometimes a specially long needle is required), and the solution injected. A few drops are often sufficient. Slight pressure should be kept on the piston during withdrawal. Some- times several injections are made at different points. The operator judges of the need for repeating the operation by the condition of the diseased parts, and by the reaction which follows. As a rule one should wait until until all signs of the previous treatment have disappeared. The principle of parenchymatous injection is not new, for a somewhat similar process, viz., the introduction of solid caustics, like arsenic and sublimate, has been in use since very early times. XV.— CASTRATION. For economic reasons, the removal of the testicles or ovaries, or the destruction of their functions, often becomes necessary. The gelding is, for most purposes, more useful than the stallion ; its conformation is modified, it is usually more tractable, and it can be worked in company with mares, a proceeding which is seldom safe in the case of stallions. The flesh of pigs and birds becomes more palatable, and animals fatten more readily after castration. Sheep fatten more quickly, and their wool becomes finer and more abundant. The milking period is prolonged in the castrated cow, and the danger of unsuitable animals breeding is removed. Dogs CASTRATION — ANATOMY. 179 are less liable to stray, and bitches cease to attract strange dogs. Finally, certain diseases of the generative organs are sometimes cured by operation. Thus in man castration has been employed for the reduction of enlarged prostate, and in the dog operation for the same object was suggested by Dr. Clarke (see " Veterinarian," 1 895) . The pathological enlargement of the gland gradually diminishes. In man osteomalacia is said to have been beneficially affected by castration, but how far the procedure is likely to succeed in animals remains to be proved. On the other hand, " spaying " in cows often removes nymphomania ; and unilateral oophorectomy, removing the cystic ovary, has been successful in sterility. Castration is also indicated by the presence of malignant tumours and fistulse, in certain injuries of the testicles, and in scrotal hernia. Castration seems to have been performed on animals since the earliest times, and is still an exceedingly common operation. Owing to the essentially different methods of procedure in male and female animals, castration will be treated of separately in each sex. Castration of Male Animals. Experience shows that male animals are best castrated young. Many of the advantages claimed for operation, such as the change in bodily form, are lost when it is too long deferred. Excluding the first few weeks of life, most domesticated animals undergo operation during the first year. The horse is an exception, because in it the testicles lie within the inguinal canal during part of the first year, towards the end of which they usually descend into the scrotum, and so become readily accessible. Moreover, horses castrated during the first year often assume a female type, whilst those in which operation is deferred develop to a greater extent. Anatomy. The testicles are suspended in the scrotum by means of the testicular cords. The scrotum and the structures it encloses may be divided from without inwards into the following layers : 1 . The outer skin. This is soft and thin, usually hairless, and in the horse black and shining ; it is very extensible, and is directly continuous with the common integument. In ruminants the scrotum shows a distinct neck ; the skin covering it is light coloured, and exhibits little hair. In swine the scrotum, which is broad and smooth, lies between the hind quarters, close under the anus ; in carnivora it is somewhat lower. 2. Beneath and intimately connected with the skin is the tunica dartos, which consists of a modified subcutis abundantly supplied with unstriated muscular fibres, elastic and white fibrous tissue. Above it is connected with the yellow elastic abdominal tunic, while a mesial prolongation, the septum scroti, serves to divide the scrotum into two equal pouches. Strictly speaking, the skin and tunica dartos together form the scrotum. 180 CASTRATION. 3. The spermatic fascia, continuous with the tendon of the external oblique muscle. 4. The cremasteric fascia, continuous with the internal oblique muscle. 5. The infundihuliform fascia, continuous with the transversalis fascia. (). The tunica vaginalis reflexa, a layer of serous membrane continuous with the peritoneum. Sir John McFadyean remarks of layers 3, 4 and 5 that the dissector will probably be unable to discriminate between them. These three layers. being more or less adherents, are often referred to as the common vaginal sheath. The tunica vaginalis reflexa is sack-like in form ; above, where it lies in the inguinal canal, it is much narrower than below, where it surrounds the testicle. Its narrowest point is rather more than an inch below the inner inguinal ring, thence it gradually dilates as it descends ; as a whole its outline resembles that of an hour glass. In the space (vaginal sac) enclosed by this prolongation of the peritoneal tunic are found the testicle and spermatic cord ; in the horse the testicle lies horizontally ; in ruminants vertically, with the epididymis pointing downwards. 7. The testicular cord is a flattened, elongated, fan-shaped structure. connected at its lower, broader end to the testicle, whilst its upper portion extends into the abdominal cavity. It is invested by the tunica vaginalis propria, a prolongation of the visceral peritoneum, and consists of the vas deferens, spermatic vessels and nerves, and the cremaster muscle. The vas deferens, which is placed at the posterior part of the spermatic cord, is a thick-walled tube, representing the excretory duct of the testicle, in large animals of the size of a goose-quill, surrounded by a fold of peritoneum and situated on the inner side of the spermatic cord ; by its convolutions it forms the epididymis, the anterior enlargement of which is termed the globus major on account of its greater size, the posterior the globus minor : the intermediate part is called the body. The vas deferens enters the abdominal cavity through the inguinal canal, passes backwards, surrounded by a special fold of peritoneum, towards the upper surface of the urinary bladder and empties by the ejaculatory duct into the urethra. The spermatic artery lies in the front part of the spermatic cord and is accompanied by the artery of the cord, and the large and tortuous spermatic veins, the convolutions of which form the plexus pampiniform is. The anterior portion of the cord (the vascular portion) therefore contains the important blood-vessels, whilst the posterior is comparatively poor in vessels, a point of great importance in connection with castration. The inguinal canal consists of a flattened, funnel-shaped space between the abdominal coats, communicating above through the medium of the inner abdominal ring with the peritoneal cavity, and below by the outer abdominal ring with the interior of the scrotum. The outer abdominal ring, an oval opening between the inner and outer limbs of the tendon of the external oblique abdominal muscle, can be enlarged by drawing back the hind limb of the corresponding side. The ring can then be felt by passing the hand gently upwards along the inner surface of the thigh and some estimate of its size can be made, a matter of importance under certain circumstances. In the horse the inner abdominal ring is an opening about | inch to H inches long, between the posterior border of the inner oblique muscle CASTRATION WITHOUT REMOVAL OF THE TESTICLES. 181 and the reflected portion of the external oblique tendon, i.e. Poupart's ligament ; it lies just in front of the transverse portion of the os pubis, inclined obliquely forwards and outwards ; '\ inch Hearer the middle line lies'the subcutaneous abdominal artery. Castration does not necessarily impty removal of the testicles. The function alone of the testicle can be destroyed, but as the process is necessarily less certain than that in which the testicles are removed, the latter is very generally preferred. No description of the subject, however, could reasonably be regarded as complete which omitted reference to the former method. A short description will first be given of T. CASTRATION WITHOUT REMOVAL OF THE TESTICLES. (a) Crushing the Testicle. A method formerly used especially in Spain, consisted in first applying clams to the scrotum and then crushing the testicles singly by blows from a wooden hammer. Apart from the uncertainty of the result, the method was barbarous and painful in the extreme. The same is true of the system of perforating the testicle with a glowing iron. (b) Crushing the Spermatic Cord. The neck of the scrotum was included in wooden clams which were hammered for several minutes with a mallet. The operation was usually performed on calves. When successful, the testicles gradually became atrophied in con- sequence of thrombosis of the spermatic vessels. Steers were cas- trated by this method in India. The operation, if it may so be called, was also performed on sheep and goats, the reason of its adoption being the danger in a hot climate of inflicting surgical wounds and the fact that after-treatment is thus dispensed with. (c) Torsion of the Spermatic Cord was formerly much employed in France for bulls, and is known as bistownage. The animal's head was fastened up securely and the operator, standing behind the animal, grasped the scrotum in both hands and drew one testicle as far backwards as possible. On releasing the scrotum the testicle was drawn upwards. By repeating this manoeuvre several times the cremaster muscle was temporarily paralysed and could no longer retract the testicle. As soon as this result was attained the spermatic cord was grasped close above the epididymis with the thumb and first and second fingers of the left hand, while with the fingers of the right hand the 182 SUBCUTANEOUS LIGATION 01 THE CORD. testicle was rotated, the lower end being brought to the top. In this position the testicle was grasped with both hands, rotated several times on its long axis, and then thrust into the inguinal canal. The remaining testicle was similarly treated and a ligature applied around the scrotum close to the outer abdominal ring and left in position for forty-eight hours. At first some swelling developed but soon afterwards disappeared, and the testicles underwent atrophy. The original procedure, which in practised hands scarcely required five minutes, has since been repeatedly modified, and has been practised on horses. Morot recommends rotating the testicles from 6 to 9 times in bulls and 9 to 12 times in rams, and then to allow the testicles to resume their natural position ; the application of a ligature is unnecessary. The animals are said to show less pain and can at once be returned to pasture. This method, however, requires more exertion and skill on the part of the operator. (d) Subcutaneous Ligation of the Spermatic Cord was first recom- mended by Martin for bulls, rams, and dogs. It is well adapted for castrating goats provided antiseptic precautions be observed. The animal is placed on its back and its legs are held by two strong assistants ; the hair is shaved from either side of the neck of the scrotum and the skin disinfected secundum artem. The spermatic cord of one side is then thrust against the outer wall of the scrotum by means of the finger and thumb and a tolerably strong silk thread passed from behind forwards through the neck of the scrotum on the inner side of the spermatic cord by means of a needle about two inches long. The free end of the silk thread is then passed through the eye of an otherwise similar but blunt-ipomted needle which is returned, first through the point of exit, then through the scrotum on the outer side of the spermatic cord, and lastly through the point of entry. The thread thus forms a loop surrounding the spermatic cord. The two ends are tightly tied together, the loose portions snipped off close above the knot, and the ligature allowed to pass into the scrotum ; the little puncture is painted with iodoform collodion. The other spermatic cord is treated in precisely the same way. Provided proper care be taken regarding antisepsis suppuration does not occur and the animal seems to sutler comparatively little. The testicles swell somewhat during the next few days, but atrophy commences in from three to four weeks, and the glands gradually and almost completely disappear. Moller states that ligation is followed by necrosis as he ascertained by experiment. To avoid the use of two needles Schmey invented a needle with the eye near the point and a screw-joint in the centre of the shank. The CASTRATION BY REMOVAL OF THE TESTICLES. 183 silk thread was passed as usual on the inner side of the cord, after which the two portions of the needle, within the scrotum, were unscrewed, the spermatic cord pushed between them, and the needle again united and withdrawn. Failing this needle or even a sharp and a blunt needle, the ligature may be returned by using the blunt end of an ordinary needle, i.e. by simply using the needle reversed during the second portion of the operation. Asepsis is not difficult of attainment if properly sterilised silk be used. The ligatures must, however, be drawn very tight, otherwise the operation fails and the activity of the glands still continues. That sexual impulse is not removed by ligation of the vas deferens alone is shown by the following experiment. One sometimes finds cryptorchids in which the epididymis lies in the inguinal canal while the testicle itself is in the abdomen. In one such case Moller ligatured and snipped off the epididymis without removing the testicle. The passage of semen then ceased but sexual desire remained as before until by a second operation the testicle was removed. II. CASTRATION BY REMOVAL OF THE TESTICLES. At the present time the commonest method of castrating horses, bulls, and other male animals is by removing the testicles. The testicles are removed either alone or with portions of the scrotum, though the latter method is only usual in calves and goats, where a ligature is passed round the neck of the scrotum. A running noose, formed of a strong piece of cord, is slipped round the upper part of the scrotum and drawn tight. Provided it be drawn sufficiently tight in the first instance the scrotum and its contents fall away in from eight to fourteen days, otherwise the loop must again be tightened. Wooden or iron clams have been used to replace the ligature. Both methods inflict needless pain and are seldom used except in calves, which, however, also suffer much more from clams or ligatures than from the more surgical method of opening the scrotum. Piot claims to have castrated two thousand bulls in Egypt without loss by using the elastic ligature, which is also valuable in the case of goats. The operation is easy and rapid and involves no loss of blood. The elastic cord is applied in a stretched condition, the ends are tied, and the testicles cut away about an inch below the ligature. Care must be taken to prevent the animals licking or gnawing the ligature which might thus be torn away. 184 CASTRATION DANGERS. Castration by removal of the testicles is accompanied or followed by various dangers which must be carefully kept in mind when operating. They are : — (a) Haemorrhage from the spermatic vessels, which under certain circumstances may prove fatal. (b) Wound infection, which almost always follows opening of the scrotum and may extend to the abdominal peritoneum, causing fatal peritonitis. In castration, as usually performed, aseptic healing of the wounds is seldom possible and their infection is almost un- avoidable, though proper precautions in regard to cleanliness and drainage generally prevent a fatal result from this cause. (c) In those methods of castration in which the tunica vaginalis reflexa is opened (uncovered operation), some danger of prolapse of bowel or omentum always exists. As a rule, however, such an accident only occurs when the inner abdominal ring is exceptionally large, or when inguinal hernia exists, for which reason the scrotum should always be carefully examined prior to operation. The various methods of dividing the spermatic cord are : 1. Tearing away of the Testicles. This method is still used in the case of calves, lambs, and swine ; after opening the scrotum the testicle is grasped and forcibly torn away. In countries like Russia and Australia, where very large numbers of lambs have to be castrated, the system is still followed ; lay castrators in South Germany also continue its use. Should the central portion of the cord not be firmly held, however, the fold of the peritoneum which surrounds the spermatic vessels within the abdomen is torn across or the divided end of the cord is withdrawn into the abdomen, where it becomes adherent to the peritoneum near the inner abdominal ring ; in either case the bowel may be incarcerated, sometimes with a fatal result (" gut- tie "). 2. Scraping the Cord is sometimes resorted to in young calves, swine and sheep. After opening the tunica vaginalis, the cord is laid across the left index finger and scraped with a blunt knife until divided. The blood-vessels are thus torn, and bleeding is usually trifling. Dawson and Hurford have successfully employed this method with horses ; the posterior portion of the cord was simply cut through and only the vessels were scraped. 3. Linear Crushing of the Cord by the Ecraseur. Many English and American practitioners employ the ecraseur for castrating stallions and other animals, the chain or loop of the instrument being passed round the covered or uncovered cord, which is slowly crushed and divided. Under the strain the tissues of the cord are more or less intertwisted, TORSION OF THE SPERMATIC CORD. 185 the less resistant coats of the artery being torn and retracted, and a coagulum forms within the vessel. 4. Broad Crushing of the Cord by the Emasculator. In England and the Colonies an instrument known as the emasculator or castrator, of which there are several patterns, is largely employed for the castration of horses and bulls. In action the castrator is rapid, humane, and generally satisfactory, there being little bleeding, and it is equally serviceable for operation in the standing and recumbent positions. The procedure varies with the age of the subject and the condition of the cord. After exposing the testicle, the whole cord may be placed within the grasp of the instrument, or the posterior portion may be severed with the knife, and the castrator applied only to the vascular cord, or the posterior and anterior portions may be crushed separately in the order indicated. The last procedure should be followed in the castration of aged horses, in which the small testicular artery may bleed after section without crushing of the posterior portion of the cord. 5. Torsion of the Cord. Torsion may be practised on the covered or uncovered cord. Torsion of the covered cord should be preferred, as there is less risk of peritoneal infection and prolapse of the bowel. In performing this operation by the uncovered method the posterior portion of the cord may be divided with a knife, and the anterior, containing the blood vessels, is twisted in one direction round its long axis until it ruptures. In horses and bulls, after opening the scrotum and applying a clam or forceps above the epididymis, in order to fix the vascular part, the cord, with the testicle, is removed by rotating the testicle and cord either with a second forceps or with the hands. Li horses, Jacoulet opens the scrotum in the middle line by a single incision through the skin and dartos, and then divides the deeper coverings of the testicles by a further incision on each side. In sheep, swine, and carnivora, the spermatic cord is fixed between the thumb and the fore-finger of the left hand, while the testicle is rotated with the right hand ; the simplest method, after dividing the cremaster muscle with scissors, being to thrust the index finger of the right hand through the centre of the cord immediately above the epididymis, and using the incision so made as a means of grasping and rotating the cord. When forceps are used for twisting the cord they should not be applied too near the fixation clam or forceps, a space of | to 1 inch being left between the two. The most popular of the older forceps for fixing the spermatic cord are Togl's which are made of two sizes, one for horses and bulls, and the other for smaller IcSB CASTRATION BY TORSION. animals, modified provided The original form of Togl's forceps has been variously by different operators, with longer limbs, which Fia. 230.— Togl's forceps for holding cord. clam instead of forceps to fix the cord during torsion. Moller uses smaller forceps give greater leverage and are easier to hold. In France Renault's for- ceps are most used. In England, Robertson suggested a special form of torsion forceps, which has been adopted by Moller. Some operators use a steel which must be held securely spermatic Kaiser's forceps for holding the cord. Most forceps are defective, inasmuch as they take too broad a hold of the spermatic cord, and thus render the effects of torsion Fig. 232.— Moller's forceps for holding the cord. irregular. The anterior and posterior margins of the spermatic cord are torn through after the second forceps have been turned once or TORSION OF THE SPERMATIC CORD. 187 twice, and the blood-vessels are divided without having first been sufficiently twisted. Bleeding is then very liable to occur, especially if a second forceps be used for twisting, and if the hold on the spermatic cord be too short. To ensure regular torsion the sper- matic cord should first be rolled together into a cylindrical mass, as occurs in using Togl's forceps. As, however, with Togl's ordinary Fig. 233. — Bayer's forceps with screw and instantaneous for holding the cord. forceps it is difficult to compress the spermatic cord sufficiently, the handles have since been much lengthened and the jaws shortened, modifications which have greatly increased their efficiency. In torsion of the spermatic cord complete closure of the blood- vessels is of prime importance. This can be secured by firmly com- pressing the portion of cord grasped by the fixation forceps or clam, Fig. 234. — Robertson's forceps for torsion of the cord, as adopted by Moller. and by slowly rotating the torsion forceps. The artery, reduced to a fine thread, is the last portion to rupture, and only yields after prolonged twisting. As a rule fifteen to twenty turns are necessary, sometimes even more. When immediate bleeding occurs it may be due to untwisting of the external coat of the vessel, to its rupture ,above the twisted portion, or to the force of the blood overcoming 188 CASTRATION BY LIGATION OF THE CORD. the resistance of the obstruction. Secondary haemorrhage, which is rare, arises nearly always from infection of the stump. Another torsion method, though little practised, may be men- tioned. It consists of the application to the covered cord of a fixation clam or forceps, section of the cord by the knife about an inch from the clam, and direct torsion of the testicular and cremas- teric arteries by means of Assalini's or other artery forceps. <>. Ligation of the Spermatic Cord may be practised (1) by trans- fixing the covered cord in front of the vas deferens with a needle carrying a double thread and ligating separately the anterior and posterior portions ; (2) by ligation of the entire cord ; (3) by first dividing the nonvascular portion with scissors and then applying Fici. 235. — Bayer's forceps in use. Many operators prefer TogPs forceps, which roll the cord together into a cylindrical mass (see text). a ligature to the anterior portion ; or (4) by immediate ligation of the artery after incision of the serous membrane of the uncovered cord. The ligatures — -aseptic twist, plaited silk, or chromic gut — having been securely tied and their ends shortened, the cord is divided within half an inch of the ligature. Ligation of the entire cord is serviceable in the castration of bulls and the smaller animals, but in the horse the first procedure, by ligating the cord in two portions, is preferable. There is no danger of the ligatures slipping, bleeding from the artery of the cord is prevented, and the cord being covered there is little risk from post-operative hernia. Lafosse recommended simple ligation of the spermatic artery. By stretching and flattening out the cord on the index finger of the left hand, and feeling carefully with the thumb the artery may be CASTRATION BY THE ACTUAL CAUTERY. 180 recognised as a stout pulsating vessel in the anterior portion of the cord. A needle is passed behind the artery, about 1J inches to 2 inches above the epididymis, and ligation performed, after which the cord is divided an inch below the ligature. In exposing the artery care must be taken to extend its flexuosities and to apply the ligature at a point which will prevent haemorrhage after section of the cord. Castration by ligation is the ideal method, but its advantages have not met with the recognition they appear to deserve. Even those operators who first recommended it have given it up. In aseptic castration the ligature has given full satisfaction. 7. Division of the Spermatic Cord by the Cautery is one of the oldest methods of castration, and even yet is frequently used in horses and bulls. In practice the testicular cord, covered or uncovered, is held by a fixation clam of wood or steel applied two inches above the epididymis, and the cautery, heated to a bright red, is used to sever the cord within three-fourths of an inch from the clam. After section has been completed the cautery is directly applied to the end of the testicular artery, and if necessary, to the artery of the cord. Hsemostasis is then tested by slightly relaxing the clam, and if bleeding occur the cautery is reapplied. The vessels should be briefly and lightly touched, as prolonged or forced contact of the cautery may remove the eschar. With the object of increasing the thickness of the eschar, powdered resin is sometimes applied to the surface of section and melted with the cautery. No doubt the resin strengthens the eschar and protects the cord, but in effecting hsemostasis by cautery more reliance should be placed on the con- traction and inversion of the coats of the artery than on the thickness of the eschar, which mainly serves to support the obstruction within the lumen. Some operators sever the cord with the knife and apply the cautery only to the surface of section, but a more rapid hsemostasis follows section by the cautery. For this purpose the wedge-headed iron, visibly red, but neither glowing nor incandescent, should be held steadily — -without sawing movements — with the edge applied across the cord. With, the cautery immediate haemorrhage should not occur, but the cord ought not to be released until pressure applied to the stump produces no oozing from the vessels. Some- times, as when section of the cord exposes several arterial loops, haemostasis is difficult, and repeated application of the cautery may be required ; and occasionally in aged stallions, owing to the flaccid condition of the vessel or other cause, the cautery fails to arrest bleeding. Secondary haemorrhage is very rare, though it may occur JIM) CASTRATION BY CLAMS. in consequence of too early separation of the eschar, infection of the end of the cord, or extensive sloughing brought about by too vigorous application of the cautery. Superficial sloughing of the end of the cord follows light touches of the dull red cautery, but the sloughs are small, generally aseptic, and harmless. Fig. 236. — Forceps for closing wooden clams. 8. Castration with Clams is represented by two methods. In the first a long incision is made through the floor of the scrotum, parallel with the raphe, dividing the skin, tunica dartos, fascial layers, and external vaginal covering, exposing the testicle and spermatic cord. The cord, having been flattened out, is then enclosed in a Fig. 237.— Wooden clams. clam, consisting of two pieces of wood about four to eight inches long, and J inch to f inch broad, united at one end by means of a cord or hinge. The open ends are brought together with special forceps and secured by tying with strong silk twist or whipcord, or by the application of a leather cap, rubber ring, or brass fastening ; and the cord is severed about half an inch from the clams. After Castration by clams. 191 an interval of twenty-four to forty-eight hours or longer the clam is removed. In the second method, which is known as the " covered operation," the coverings of the testicle — skin, dartos, and fascial layers — outside the tunica vaginalis reflexa (or tunica vaginalis scroti) are carefully divided, and then separated by stripping from the testis and cord as high as may be required. The clam is applied to the cord above the epididymis and over the parietal serous covering (tunica vaginalis reflexa), and secured as above described. The testicle with the lower end of the cord is removed with scissors or a knife ; the clam is left in position for twenty -four to forty-eight hours, and in cases of hernia it is advisable to allow the clam to fall off. The clams should be made of hard, tough, light wood (elm, boxwood, oak, ash, or hickory), and their edges should be well rounded to prevent injury to the surface of the cord. The internal or pressure surfaces may be flat or grooved, and either undressed, or medicated with caustic or anti- septic pomade, containing copper sulphate, arsenious oxide, zinc chloride, or corrosive sublimate. Sometimes the pressure surfaces are coated with oil of tar and sprinkled with finely powdered mercuric chloride. Moller recommends a concen- trated solution of sublimate in gum arabic mucilage, painted two or three times over the pressure surfaces of the clams. Schlammp applies to the clams a strip of gauze saturated with sublimate solution ; the gauze adheres firmly on drying and greatly facilitates removal of the clams after operation. The furrow on the pressure surfaces of the clams was probably first used with the idea of preventing the clams slipping off, an object which, without doubt, it fulfils. It also facilitates the application of disinfectants, however, and increases the intensity of the pressure, inasmuch as it concentrates it on a narrower surface. Various forceps and screws have been constructed for closing the clams, but the instrument most commonly used is shown in Fig. 236. Fig. 238. — Iron clams. 102 ASEPTIC CASTRATION. Bleeding may follow operation by clams which are warped, insecure, or not tight enough ; or the cord having been severed too close to the clam the artery may recede from its grasp, and occa- sionally the horse in an effort to remove the clam tears the cord. Secondary haemorrhage sometimes occurs at the time the clams are removed, owing to too much force being employed, or subsequently from infection of the clot, which quickly disintegrates. The clams should not be pulled off ; it is safer to cut the fastenings and allow the clams to fall. Clams have been condemned as unsurgical, seldom aseptic, exposing the scrotal wounds to infection, unnecessarily painful, and inconvenient. But experience shows that clams in good condition and properly applied to the cord are safe and effectual in preventing haemorrhage, and of great advantage in the castration of robust and aged horses in either the standing or recumbent position. The greatest danger results from using septic or dirty instruments. Practitioners should exercise scrupulous care in this respect, and should disinfect all instruments before and after use. New clams should be used for each case. Aseptic Castration. As was to be expected, soon after the practice of antisepsis became popular, experiments were made to ensure castration wounds healing by primary intention. Bayer first approached this problem in 1881, and was followed at a later date by Frick. Bayer had four successful results among fifteen horses operated upon. At that time he simply divided the cord and ligatured bleeding vessels, but frequently had secondary bleeding owing to the vessels escaping from the ligatures. He then resorted to simple ligation of the entire cord. Here also he had healing by first intention, but the horse was often compelled to lie down soon after operation on account of enormous swelling of the scrotum. In every instance he found that the ligature had slipped off. In one instance he noted the accident occurring. At every pulsation of the spermatic artery the ligature yielded, at first almost imper- ceptibly, afterwards at a faster rate. ■ When the ligature was held with the finger the cord was drawn out of the loop. Frick had seven successes in twelve cases. Guttman castrated two horses, two boars, two dogs, and a goat with antiseptic precautions, in each case obtaining healing by primary intention. Plosz was equally successful with six stallions. One must not forget, however, that observance of the necessary principles of asepsis is much more difficult in private practice than in clinical institutions. Moller operated several times, but with ASEPTIC CASTRATION. 193 varying results. The animals should be prepared, cast, and anaesthetised as above described. The necessary arrangements having been made, and the hands, instruments, and ligatures sterilised, the first step consists in thoroughly disinfecting the field of operation. The scrotum, penis, and their surroundings are care- fully washed with soap and water, rubbed with alcohol, and rinsed with sublimate or other disinfecting solution. The upper hind limb and the hobble restraining it should be moistened to prevent hairs falling on the operation wound. The other precautions are similar to those suggested in connection with antiseptic operations. The operator first grasps the right testicle, presses it towards the base of the scrotum, incises the skin, dartos, fascial layers, and tunica vaginalis, and allows the testicle to protrude. Having secured this, he ligatures the spermatic cord with two or three ligatures, according to its thickness. To facilitate operation, the cord is compressed by forceps, the ligatures are applied below this point, aseptic catgut or silk being used, and the spermatic cord is divided half an inch below the point of ligation. Any blood that may have escaped is removed with sterilised cotton wool, the wound in the scrotum closed with button sutures, the tunica vaginalis, if possible, being included, though this is often difficult. The sutures should be inserted deeply, so as to bring the subcutis in contact over a considerable area. After the left testicle has been removed in a similar way, the scrotal surface is rinsed with a disinfecting fluid, powdered with iodoform or iodo- form and tannin, and covered with a thin layer of wadding, which adheres to the skin by means of the tannin, and remains as a pro- tection after the horse rises. The difficulties in obtaining asepsis are less apparent during operation than afterwards, inasmuch as a bandage is difficult to apply, and a really secure protection against infection can scarcely be devised. Irrigation of the wounds is usually neither necessary nor desirable, as it retards healing. Aseptic castration has not yet been seriously practised, and is scarcely likely to become common on account of its many difficulties. Whilst ordinary castration, with exposure of the testicle, can be performed in from four to ten minutes, aseptic castration demands from half to three quarters of an hour. Moreover, it offers no great advantages. Castration by ordinary methods is seldom followed by bad results. Nielsen castrated forty-one stallions and eleven boars by torsion, without using sutures, and only saw swelling and suppuration in two of the stallions, a result which bears favourable comparison with those afforded by aseptic castration, and is worthy 194 CASTRATION OF STALLIONS. of serious consideration in choosing a method. The difficulties inherent to asepsis arise partly from external circumstances, such as the difficulty of applying a protective dressing, which many animals will not endure, and partly from the fact that even with the greatest care bleeding cannot always be prevented. Bleeding usually sets in after the animal has risen, and originates in the veins of the common vaginal sheath. Blood collects in the scrotum, and endangers aseptic healing. In cryptorchids, in which this sheath is absent, asepsis is therefore more easily attained than in ordinary stallions, as is shown by the experience of Bayer, Guttmann, Plosz, and others. Until these difficulties can be overcome aseptic castration will remain a strictly academic operation. (1) CASTRATION OF STALLIONS. For reasons already given the second year of life is that usually selected for operation, as it appears the most generally suitable period, and the animal probably suffers less pain than it would at a later period. In this country, however, most animals are castrated during the first year. Stallions of any age can be castrated without danger, provided the genital organs are normal, and the rules of antisepsis are observed. Before operation the scrotum is examined, to discover the existence of hernia, and note is taken of the condition of the sper- matic cord, and width of the inguinal ring. Yearlings are best kept without food on the morning of the day of castration ; older, more excitable, and more powerful animals should be kept on short diet for some days before, unless they have been regularly worked. Some authorities condemn restricting the diet of animals before operation, because it favours prolapse of omentum, or bowel, and castrate yearlings and older horses without any such preparation. Such points are probably of little importance, though it cannot be denied that the small bowel is less likely to pass into the inguinal canal when full than when empty. Racehorses should not be castrated when in training, as their muscular strength is so great that bones may be broken during operation. In England, America, France, and other countries, horses are often castrated in the standing position, though this is certainly not favourable to the proper performance of the operation, as is conceded even by supporters of the method. It succeeds well enough in quiet phlegmatic animals, which, however, can also be cast without much danger. Joyeux is believed to have been the first to castrate horses CASTRATION WITHOUT CASTING. 195 standing. The method was afterwards modified by the American cas- trator Miles, and more recently has been recommended by a number of operators in England, and by Salinier, Cagny, and others in France. Joyeux operated from the right, Miles from the left side, both with clams, the former by the covered, the latter by the uncovered method. Many veterinary surgeons use the emasculator which greatly facilitates operation in the standing position ; others employ the ecraseur. Joyeux applied blinds and a twitch, and fastened the horse up short by means of a strong head collar. After placing hobbles on the hind feet, and connecting them to a cord passed round the neck, the operator takes up his position facing the horse's right flank ; with his left shoulder somewhat lowered and his left arm advanced he then grasps the scrotum and draws the testicles one by one downwards, the left hand gliding downwards along the course of the spermatic cord. Immediately the cord has been secured by the left hand, the layers of the scrotum are successively incised from in front backwards, care being taken to protect the left thumb. On dividing the skin and tunica dartos, the testicle ' Fig. 239. — Screw instrument for closing wooden descends, whereupon clams, the operator separates these tissues from the common vaginal covering, and the assistant, who stands at the horse's left side, passes a clam from behind over the spermatic cord. This accomplished, the operator grasps the forward end of the clam, applies the forceps or screw, and the assistant ties the clam. During the operation the forceps must be pressed towards the abdomen, and in a backward direction in order to prevent the spermatic cord being torn through. After snipping off the right testicle the left is removed in the same way. Salinier operates by means of caustic clams, and first of all applies a ligature around the neck of the scrotum. Whilst the operator draws the testicles downwards the ligature is applied and tied by an assistant ; the more tightly it is drawn the quieter does the horse remain during operation. Trasbot, whose practical experience was very great, altogether condemned castration in the standing position. Miles castrated colts from the left side. He tied the animal up short with the right side against the wall, and placed a scaffold pole 196 < ASTRATION OF STALLIONS. or similar piece of round wood against the animal's left thigh in order to prevent it kicking the operator. The clam was applied over the uncovered spermatic cord and fastened with a leather ring, which was slipped over the conical end. This obviated the some- what tiresome necessity for tying. In England, castration in the standing position is now largely practised. Griffith describes the operation as follows : — An assistant stands at the animal's left side, with his right shoulder against the animal's left. A second assistant holds and hands the necessary instruments. The operator, who also stands on the animal's left side, slips his left hand along the animal's abdomen as far as the scrotum, grasps the right testicle, and draws it down to the bottom of the scrotum, which is immediately opened by an incision with the right hand from before backwards. He then discards the knife. The left hand at once grasps the protruding testicle and draws it backwards, whilst the right hand passes the open clam between the hind limbs and slips it from behind forwards over the spermatic cord. There- upon the left hand seizes the free ends of the clam and presses them together. As soon as it has been ascertained by means of the right hand that only the spermatic cord, and not a portion of the scrotum is included in the clam, the latter is grasped with special forceps and firmly pressed together. The front ends are then secured with string and the testicle cut away. The left testicle is removed in a similar way. Griffith states having thus castrated 140 horses, varying in age from one to twelve years, during the course of one summer, without any noteworthy mishap. In practising the standing operation too much restraint is not advisable, and the operator should not press or lean against the horse's flank as this may cause the horse to crouch or fall. Abroad it is usual to cast the horse for castration on the left side, the feet and hind quarters being somewhat higher than the body, though the dorsal position also has advocates. The right hind limb is drawn forward until the hoof is in contact with the animal's chest and the whole limb is somewhat abducted, and is then secured. It must not, however, be drawn too far forwards ; on the other hand, should it not be drawn sufficiently far the operator may be injured by the point of the hock. This limb should not be fastened too tightly, as otherwise the animal may make violent extension move- ments, the resistance to which may cause fracture. It is preferable to pass a piece of webbing around the fetlock and hoof, and fix the limb in a position of plantar flexion. CASTRATION BY CLAMS. 197 "■•"' . ^ ■:■'-■■-'.: :%^C &«S£\- The dorsal position has the advantage that prolapse of bowel is less likely to occur, but it necessitates more assistants ; the side position is equally useful, provided a careful examination be made before operation. Before casting, nervous thoroughbred horses should be given an anodyne, and after casting they should be anaesthetised to prevent accidents like broken back, myositis, muscle rupture, etc., which are sometimes caused by violent struggling during operation, as when the spermatic cords are compressed. Since adopting these precautions Moller and other operators have had no cases of spinal fracture. Roder claims to have rendered even the application of clams painless by injecting cocaine into the scrotal subcutis. (a) Castration of the Stallion by the Application of Clams. Although operation with clams receives first notice it has been largely re- placed by other methods, and particularly by torsion of the spermatic cord, which has found increasing accept- ance and on the whole seems preferable. (a) Castration by the uncovered method. The con- dition of the spermatic cord and outer abdominal ring having first been ascertained by palpation, an assistant cleanses the scrotum, penis and surrounding parts with soap and water, rinses them with sublimate solution, and afterwards carefully mops up all superfluous moisture with a clean cloth or tampons of cotton wool, giving particular attention to the fold of skin between the inside of the thigh and the scrotum, so that no fluid may be left to find its way into the wound during operation. Kneeling behind the horse the operator first grasps the left testicle by passing the left hand from before backwards around the left spermatic cord. In carrying this out, the open right hand is thrust between the scrotum and the surface of the left thigh, whilst the left hand endeavours to grasp the spermatic cord from in front, and to thrust the testicle towards the base of the scrotum. The correct position of the testicle is known by the fact that the scrotal raphe Fig. 240. 198 CASTRATION BY CLAMS. lies parallel to the testicle on its inner side. The skin covering the testicle is next rendered tense and a long incision made through it, parallel to and about an inch from the scrotal raphe, by means of a sharp convex knife. This incision divides the skin, tunica dartos, and other coverings, and may extend into the substance of the testicle itself without detriment. Some operators first incise only the skin and tunica dartos, opening the sac of the tunica vaginalis with a second incision. Nothing is gained by this method. It is, however, of great importance to make the incision in all three coats well forward and large enough, in order to provide for effective drainage at a later stage. This is particularly true in the case of the sac of the tunica vaginalis. The testicle will often pro- trude even if the scrotum be insufficiently opened, but such a method is to be avoided. Pflug and B r u c h e r recommend first incising the tunica vaginalis reflexa in front and afterwards behind, leaving a portion in the middle undivided, and afterwards uniting the two incisions. This ensures a long opening, which, if necessary, may be extended with scissors. The operator now discards the knife, grasps and draws forward the exposed testicle with the right hand, whilst with the left he thrusts back the scrotum and other envelopes, so as to expose the cord sufficiently to permit of the application of the clam. More extensive exposure than this should be avoided, as it only favours infection. At this moment, as a rule, animals endeavour to retract the testicle by means of the cremaster. One therefore waits a few moments, exercising steady traction on the testicle, and drawing it forward sufficiently for the clam to be applied above the epididymis. The necessary movements should be made slowly, and excessive tension or dragging on the cord should be avoided. Should contraction of the cremaster muscle be long con- CASTRATTON OF STALLIONS BY CLAMS. 19!) am^^,. tinued, the animal may be struck smartly with the open hand, but as a rule the testicle can be drawn forward without difficulty as soon as the first struggles have subsided. The operator then grasps a clam with the left hand and passes it from in front backwards over the spermatic cord (which should be flattened out as much as possible), giving the clam such a direction that it will hang horizontally when the animal is standing, and will at least be above the epididymis. When the cord is exceptionally long the clam should be applied proportionally higher ; it may, in fact, be placed as high as possible, without exercising undue tension on the cord. The posterior (open) ends of the clam having been compressed with the fingers of the left hand so that the clam firmly grasps the spermatic cord, the tes- ticle may be released while the forceps or screw is applied. During closure of the clam by either of these instruments the animal usually struggles un- less previously anaes- thetised. To prevent injury or tearing of the spermatic cord the twitch may be shaken whilst the forceps or screw is being closed, and the clam should be pressed against the animal's groin. The- operator should have made sure while applying the clam that no part of the scrotum was included in it, but in any case at this stage of the operation he should again examine the parts before finally securing the clam. Care is also required to prevent the spermatic cord slipping beyond the crushing surface of the clam. Provided all is found satisfactory, the clam is secured by a surgical knot, drawn very tightly. The spermatic cord is then divided with a knife or scissors, one half to one inch below the clam. The right testicle is then removed in a similar way, care being taken not to displace the clam already applied or to throw Fig. 242. 200 ('ASTKATK)N BY THE COYKKIH) METHOD. any strain on the left spermatic cord. The wound and inner surface of the left thigh are then carefully cleansed, the sheath is drawn somewhat forward, the exposed stumps of the spermatic cords are powdered with iodoform, and the horse is allowed to rise. Formerly it was usual to divide the posterior non-vascular portion of the cord before applying the clam. The method is not commend- able, because the clam is then only suspended by the anterior portion of the cord, which readily yields, allowing the clam to descend. In the method described the clam, on the contrary, is suspended by the cre- master and the vascular portion of the cord. The horse may be placed in a well venti- lated stall, or loose box, and tied up short in order to prevent its lying down. Its tail, which should previously have been plaited, is now fastened to one side by attachment to the sur- cingle or to the shank of a web halter passed round the neck. Most animals will at once eat hay, which should be given, as feeding dis- tracts attention from the seat of operation, and prevents restlessness. Should the animal strain greatly, it should be watched, and, if restless, it may be walked about at short intervals, or given an anodyne. In castration by the covered method the animal is prepared and cast in precisely the same fashion as before described. The operator first grasps the left (lower) testicle, taking particular care that the scrotum is tightly stretched over it. The incision is at the same point, but is made very long, dividing, however, only the skin and tunica dartos, and exposing the fascial layers which lie between the latter and the tunica vaginalis reflexa. By light cautious strokes with the knife these layers are divided in the long axis of the testicle until the tunica vaginalis reflexa, readily recognised by its dull Fig. 24:5. CASTRATION BY THE UNCOVERED METHOD 201 greyish-blue tint, is exposed. The knife is then discarded, the operator grasps the testicle with the right hand and with the left endeavours to free the tunica dartos, etc., from the tunica vaginalis reflexa sufficiently far for a clam to be applied to the spermatic cord above the epididymis. To facilitate the application of the clam, the connective tissue layers should, if possible, be entirely separated from the underlying tunica vaginalis. The clam, which must be somewhat larger than that used in the uncovered operation, is applied as before described, care being taken that it includes the whole breadth of the spermatic cord. After carefully tying the clam, the testicle and base of the cord are excised with a knife or scissors. The second testicle is removed in a similar way, the parts are cleansed, and the sheath drawn forwards. The horse is then allowed to rise. The after-treatment is as above described. A modification of this method introduced by Degive consists in opening the tunica vaginalis and exposing the testicle, but when applying the clam, grasping and drawing down the edges of the vaginal sheath so as to include them in the clam. It requires some practice, because the vaginal sheath is very apt to elude the operator, and it is difficult to again grasp and draw it forward. Attempts were made by applying a pair of forceps to overcome this difficulty and facilitate operation, but they necessitated the presence of a skilled assistant. Moreover, the only advantage this method has over the ordinary covered operation is, that when the common vaginal sheath is short, it is less likely to be overstretched. It is, however, useful when one has to deal with scrotal hernia which has only been discovered at the moment of opening the tunica vaginalis. In castration by the uncovered method the clams are removed after twenty-four hours, in many cases even earlier ; in young animals especially they may be removed without danger within six to twelve hours after operation. In Sweden and Denmark, Tidholm's method is commonly used for castrating horses. Clams are applied to the spermatic cords, which are firmly compressed. The clams, however, are almost immediately removed, a ligature is applied, and the testicles removed. In castration by the covered method, the clams are usually left in position for forty-eight hours, though Degive recommends leaving them three to five days. Moller also approves the longer period, and finds that inflammatory symptoms are then less marked, and fever rarer than when the clams are removed forty- eight hours after operation. This is explained partly by the fact that after the clams have been several days in position the necrosing stump of the spermatic cord is not so liable to be retracted upwards, 202 CASTRATION — REMOVAL OF THE CLAMS. carrying infection into the upper portion of the sac of the tunica vaginalis. It must also be remembered that after a few days the edges of the wound become infiltrated with plastic material, and are therefore less likely to be infected than twenty-four hours after operation. At the time of removing the clams, however, the greatest care cannot prevent circumstances arising favourable to infection by wound discharges. It is common experience that inflammatory swelling or fever first appears on removal of the clams. It is best first to attempt removal of the clams without using the twitch ; should the attempt fail it can be applied. Having provided himself with a clean pocket-knife, the operator places himself at the horse's left side, the left hand resting on the animal's loins ; the thumb of the right hand is then placed against the front of the clam, the knife is slipped between the back ends and the string uniting them is divided. At the same time the knife is rotated in the hand, forcing the two portions of the clam apart. Discarding the knife for a moment the operator seizes the free ends of the clam with both hands, and slowly opens them as far as possible. The spermatic cord is then usually found to be adherent to one side of the clam. If no bleeding occur the cord is cautiously separated by sliding the thumb from in front backwards along the depression in the centre of the clam. The operator then throws the clam to one side, rinses his hands in sublimate solution or other disinfecting fluid, and endeavours to free the spermatic cord from any adhesion with the scrotum by passing the index finger around the stump of the cord. If bleeding should follow removal of the clam' the cord should be ligatured, or the clam may be replaced. The second clam having been removed, a strong stream of sublimate solution or clean cold water should be directed into the scrotum ; this has the double effect of partially cleansing the wounds and of causing retraction of the spermatic cords. After removal of the clams the horse should be exercised daily for half an hour or longer, or turned out ; in the country full-grown horses may be put to light work. Experience has shown that long rest in the stable is disadvantageous. The good effects of exercise are largely due to the fact that they favour escape of discharge. For a similar reason it is important to make the incision through the scrotum well forward and as large and dependent as possible. The extensive swellings which sometimes follow castration are almost exclusively due to want of cleanliness in operation or to retention of wound discharges. Special treatment of the scrotal wounds is seldom necessary. They should be cleansed daily with an antiseptic CASTRATION U¥ STALLIONS. 203 lotion until suppuration ceases. If after removal of the clams the horse is turned out the scrotum may not require further attention. When fever, or much post-operative swelling cccurs, the wounds should be opened with the disinfected hand, and thoroughly washed out with an antiseptic fluid. (b) Division of the Spermatic Cord with the Actual Cautery. A second method, frequently used in the horse, consists in dividing the spermatic cord with the actual cautery. It has already been described (p. 189), and has the advantages over castration with clams that it is aseptic, and that operation is at once complete. Provided proper care be taken, secondary bleeding is rare, and the local reaction, evinced by swelling, etc., is seldom more marked than after other methods. Care must be taken, however, to make the incision in the scrotum and tunica vaginalis reflexa sufficiently large to ensure free drainage. (c) Torsion of the Spermatic Cord if carefully performed is also a reliable method, and has the great advantage of rendering a second visit to the patient unnecessary. Moller and many others recommend this method for castrating stallions, and it is largely practised in Germany. Operation by torsion seems less painful than castration with clams, which, even when skilfully carried out, must cause a certain strain on the spermatic cord. Moreover, healing is more rapid after torsion. In torsion the stump of the cord seldom becomes necrotic ; and severe swelling, so marked after castration with clams, is relatively uncommon, and scirrhous cord is a rare sequel. The chief and practically the only objection to this method consists hi the danger of secondary haemorrhage. By using proper forceps, and operating carefully, bleeding can, however, be reduced to a minimum, even in the case of old horses. Nevertheless the owner's attention should be drawn to the fact that slight bleeding may occur, though it is seldom of much importance. When bleeding occurs it can be stopped by the application of artery forceps to the vessel, or by ligating the cord. (d) Castration with the Ecraseur. In America and England the ecraseur has been much used for castrating stallions. After exposing the testicle and spermatic cord the chain of the ecraseur is passed over the testicle and slowly drawn tight, dividing the cord just above the epididymis. The method has found acceptance at the hands of many practical men, though it seems to possess no particular- advantage over carefully performed torsion. (e) Castration with the Emasculator. In England and the Colonies the emasculator is becoming rapidly popular as a very 204 CASTRATION OF MALE RUMINANTS. convenient instrument for the castration of colts in the standing position. (f) Ligation of the Spermatic Cord is seldom practised on the stallion. Its disadvantage consists in the fact that the ligature material remains in the wounds, causing irritation, and sometimes inducing chronic funiculitis. The use of catgut does not overcome this draw- back, because it is not absorbed as rapidly from the stump of the spermatic cord as from an aseptic granulation surface ; experiment has shown that absorption requires at least one or two weeks. Moreover ligation of the spermatic cord is not so easy as might be imagined. Even when the ligature seems quite tight it may slip or become loose from the pulsations of the artery. Should the operator decide to castrate by ligation of the cords, several methods are open to him (see p. 188). The most surgical method is ligation of the spermatic artery in continuity, and when carefully performed with antiseptic precautions is quite safe. Finally, it should be said that in castration less depends on the method than on the way it is practised. As the method most commonly employed is usually best carried out, it results that many practitioners after a short trial of a new method, return to their older procedure. Handiness and cleanliness exercise a marked influence on the success of operation. As regards cleanliness, one can never be too thorough, and although complete asepsis may not be secured, cleanliness, nevertheless, remains an important factor in ensuring success. (2) CASTBATION OF MALE EUMINANTS. Although the same principles apply to the castration of ruminants as to that of horses, yet variations in anatomical arrangement of the organs of generation and in external circumstances necessitate numerous modifications. Apart from goats, which appear par- ticularly sensitive to ordinary methods of castration, ruminants seem to bear operation better than horses. Bull calves may be castrated by torsion or ligation, the elastic ligature being used if desired. Older animals may be castrated with clams by the covered method, or the emasculator may be used. Bulls bear castration best during the first year of life, an age at which the operation is also most easily performed. Bull calves destined for early slaughter are usually castrated when two or three months old. Should the animals be intended for draught purposes, CASTRATION OF BULLS. 205 however, castration is commonly postponed until the second year, as the neck and shoulders are then better developed. The operation may be performed in the standing position ; only old vicious bulls are cast. For operation in the standing position the animal is tied up as short and as strongly as possible, a bull holder is applied, and a rope is passed in a figure-of-8 fashion around the hind limbs above tjie hocks. One or two strong assistants may be placed on either side of the quarters to prevent the animal moving laterally. The operator stands behind the animal, grasping the scrotum with the left hand. Two incisions, H to 2 inches in length, are made in the lower extremity of the scrotum, the testicles are pressed out and the testicular cords are secured with fixation clams, while torsion is effected by hand or by means of forceps. When castrating with clams, the operator incises the base of the scrotum in two places (or cuts it off), dividing the skin, dartos, connective tissue and serous coverings of the testicles. Short clams are applied to the cords which are then severed, and the clams are left in position for five or six days. Instead of incising the scrotum in two places, the scrotum and dartos may be divided in the middle line, after which incisions are made to the right and left respectively, exposing the deeper coverings and enabling the testicles to be enucleated. A clam is then applied to each cord, or the two cords may be included in one clam. In castration by the covered method, the procedure is identical with the preceding, except that the incision of the scrotum does not include the tunica vaginalis reflexa. Castration with the actual cautery is performed as in the horse. Bull calves may be castrated by scraping the cord as already described. " Bistournage," i.e. torsion of the spermatic cords within the scrotum, is also performed. When successful it is followed by atrophy of the testicles. It has chiefly been practised on bulls, rams, and goats, and only occasionally on stallions. (See Moussu and Dollar's Diseases of Cattle, Sheep, Goats and Swine, pp. 751-755). In South Germany, and especially in Bavaria, bulls are very often castrated with the "caustic ligature," that is, a strong cord saturated with a mixture of equal parts of sublimate and gum arabic dissolved in water. Many experienced operators warmly recommend this method, though some have noticed after- symptoms of mercurial poisoning, especially in young animals. An extensive eruption, which may persist for a month or six weeks, occurs over the whole body, and is accompanied by local depilation. This has been attributed to excess of sublimate in the ligature, and 206 CASTRATION OP SHEEP AND GOATS. some operators therefore recommend saturating it with a solution of three parts of sublimate in thirty parts of collodion. The caustic ligature has the advantage of more rapidly dividing the spermatic cord, and therefore of separating sooner, whilst the sublimate exercises a disinfecting action both on the cord itself and on the wound. Some practitioners, however, have noted severe swelling after this operation. Eckmayer ligatures the exposed spermatic cord with carbolised silk, and removes the testicle half an inch below the ligature. He operated thus on more than 100 calves without any bad result. Gunther recommends the use of the elastic ligature for bulls. Another method of castration has been recommended. After opening the scrotum the spermatic cord is perforated between the vascular and non-vascular portions with a knife, and the index finger of the left hand is inserted in the slit so produced. The testicle being removed with the knife, the stump of the cord is passed through the slit, and tied in a knot. Should bleeding not immediately stop a second or third knot may be tied. Some operators first divide the non-vascular portion of the cord with the knife, then, after grasping the blood-vessels firmly with the finger and thumb or with forceps, divide these low down near the testicle. One or more knots are then tied as high as possible on the vascular cord and drawn tight. As soon as the operator is satisfied that bleeding is no longer to be feared the free end of the vascular cord is snipped away three- quarters of an inch below the knot or knots ; the latter are returned into the sac of the tunica vaginalis and thrust as high up as the fingers can reach. This method is particularly recommended for old bulls ; but in calves, as the spermatic cords are not fully developed, the knots are sometimes difficult to tie. The greatest cleanliness must be observed. Wehrhahn has shown that bulls may be castrated aseptically, though only at the cost of much time and care. Sheep are best castrated between the fourth and sixth weeks. The animal is laid on a table (lambs are held by the legs), the limbs being grasped by an assistant or tied together ; old rams should be placed on the back, and held by a couple of strong men. In lambs, scraping or torsion is the best method. Old rams may also be castrated by torsion, provided sufficient care be taken, though ligation is also successful. Clams are very seldom used in sheep. The scrotum is either opened as in the horse, or its base is cut off, a method which ensures free drainage. Goats are best castrated by subcutaneous ligation of the spermatic cord or by means of the elastic ligature, as before mentioned. CASTRATION OF SWINE, DOGS AND CATS. 207 (3) CASTEATION OF SWINE. Swine are usually castrated during the first few weeks or months of life, though not infrequently one is required to operate on old boars. No particular danger attends castration of these animals provided that previous to operation the scrotum and inguinal canal be examined for inguinal hernia, which in them occurs with some frequency. The pig being laid on its back on a table and held by one or two assistants, the operator presses the testicles towards the base of the scrotum with the left hand. He then incises the covering of the testicles, parallel to the scrotal raphe, and about § to | inch distant from it, allowing the testicles to protrude. Although in young animals simple division of the spermatic cord with scissors is not always attended with danger, yet torsion is preferable, and is carried out, after dividing the posterior portion of the cord, by passing the index finger through the spermatic cord, just above the epididymis, whilst the cord is grasped a short distance above the epididymis with the thumb and index finger of the left hand. The index finger of the right hand is then rotated, and the cord twisted until the testicle falls away. Another method consists in dividing the posterior part of the cord with a knife, laying the remaining portion on the index finger of the left hand, and scraping it with a blunt knife until completely divided. Older boars are best castrated with clams, ligature, or cautery. The operation can be performed in the standing position, though the animal's head must be firmly secured, and its hind limbs fixed by passing a couple of poles between the legs, so that it can neither lie down nor move to either side. The operation is, however, most conveniently performed with the animal lying on one side. No particular after-treatment is necessary, but the animal should be placed in a separate, cool, clean stall. The clams can be removed after twenty -four hours, though they are generally left in position until they fall away. Griin recommends castrating boars by ligating the spermatic cord with a dry, thin catgut ligature. (4) CASTEATION OP DOGS AND CATS. Dogs bear castration well at all ages. The animal is placed on its back, and the scrotum and tunica vaginalis are opened as above described. In young animals the spermatic cord may be simply snipped through with scissors or scraped with a knife. The point of division is just above the epididymis. In older animals ligation 208 COMPLICATIONS DURING CASTRATION. is preferable, as bleeding may be prolonged by the animal licking the parts. Cats are similarly treated. Some operators fix the animal by enveloping the fore-part in a sack ; an assistant holds the hind legs. Scraping, twisting, or ligation may be used. (5) CASTEATION OF BIEDS. This is on the whole simple, but the operation requires some practice. The cock is the bird most often castrated ; the bean-shaped testicles lie in the abdomen. Operation is performed between the second and sixth weeks of life, or when the habit of crowing commences and the comb assumes a red colour. An assistant holds the bird on its back in his open hands, with its beak pointing towards the operator, and presses down the feet with his thumbs. The feathers are plucked out or cut away for a distance of about | inch in front of the anus, and a transverse incision about 1£ inches in length made through the thin abdominal wall. At this stage care is required to avoid damaging the abdominal contents. The incision is preferably made with button-pointed scissors, the thin abdominal wall being raised in a fold with dissecting forceps, incised with scissors, and the wound enlarged to the necessary extent. The operator then passes the disinfected index finger of the right hand into the abdominal cavity to the spot where, externally, the posterior angle of the scapula may be felt on the ribs, meanwhile pressing the abdominal contents to one side. At this point there lies, on either side of the vertebral column, a firm body, the size of a horse-bean — the testicle — -which is first separated from the ribs by means of the bent finger, and then drawn backwards through the wound where it is simply pinched off. The removal of the testicle is indeed scarcely necessary, it being sufficient to remove it from its original position. Any protruding bowel is returned, and the wound in the abdominal wall united with closely placed stitches. The bird is placed alone in a dry run, and is given soft food and clean water. Recovery is complete in about eight days. COMPLICATIONS OF CASTRATION IN MALE ANIMALS. Adhesion of the Testicle to the Tunica Vaginalis Reflexa. This condition is only of importance in the operation with exposure of the testicle, and the adhesion may often be simply broken down by means of the thumb or round-pointed scissors. Where it is more extensive and firm, as shown by the fact that the testicle fails to CASTRATION — COMPLICATIONS. 209 protrude after incision, although it may even have been incised, a second incision may be made to one side of the testicle and enlarged with button-pointed scissors until the testicle is freed. In the event of this also failing, the tunica vaginalis can be divided with scissors above the testicle or epididymis, and the base of the tunic removed together with the testicle. Should the adhesion extend to the spermatic cord, castration must be completed by the covered method. Prolapse of the Omentum. In horses and swine portions of the omentum are not uncommonly found in the scrotum, although large portions should be recognised on examining the scrotum prior to operation. Smaller pieces may escape observation, however, and when the tunica vaginalis is opened, often become greatly increased in a short time, in consequence of the animal straining. The con- dition is seldom dangerous. The operator waits until the straining ceases, gently draws the piece of omentum forward, and, if it be limited, snips it off with scissors. Should it contain important blood- vessels, these must be ligatured with sterilised catgut or silk, cut through, and the remainder of the omentum returned into the inguinal canal and thrust back into the abdominal cavity. The omentum seems little prone to inflammatory processes ; danger of peritonitis is small. Prolapse of the Bowel. Though prolapse of omentum is seldom of particular importance, that of the bowel is very serious. In order to avoid this complication, the scrotum and spermatic cord must be very carefully examined before castration. A loop of bowel may, however, pass into the inguinal canal during operation, or a portion too small to be recognised with certainty by external manipulation may have been present in the tunica vaginalis beforehand. Under such circumstances, the prolapsed portion very rapidly increases in size during operation, in consequence of the animal's struggles. Prolapse is favoured by dragging on the spermatic cord, which dilates the inner abdominal ring. It occurs oftenest in old stallions, either during castration or after the animal has risen. Occasionally it appears later, sometimes when the clams are removed. Immediately the bowel appears, however small may be the portion, the animal should be placed on its back and the hind quarters raised as high as possible. The greatest care should be taken to prevent the bowel being soiled or injured. Whilst the animal is being moved, the operator should firmly grasp the scrotum to prevent the prolapse increasing, which, under some circumstances, it very rapidly does. As soon as straining ceases, the bowel must be returned through the inguinal canal into the abdominal cavity. Should this 210 COMPLICATIONS AFTER CASTRATION. prove difficult, the operator may pass one hand into the rectum and assist reposition by pulling on the displaced portion of bowel. To prevent recurrence of the prolapse, a clam is applied over the tunica vaginalis reflexa ; as in operation for inguinal hernia, the tunica vaginalis may be twisted around its long axis. The after-treatment is similar to that in the operation mentioned. Entrance of Air into the abdominal cavity is, of course, only possible when the tunica vaginalis is opened, and is recognised by a sudden gurgling or bubbling noise. It is favoured by abnormal patency of the inner abdominal ring, is of rare occurrence, seldom of much importance, and only dangerous when blood passes into the abdominal cavity along with the air. In such case peritonitis may result from the introduction of infective material. Immediately the noise is heard, the operation wound should be covered with the hand. UNFAVOURABLE CONSEQUENCES OF CASTRATION. No special treatment is necessary after castration. Horses are placed in a clean stall or loose box provided with fresh litter. They may be tied up, and, for a time, kept under observation, in order to see whether straining occurs, in which case the animal must be checked by calling to it, as prolonged straining might easily cause prolapse of the bowel. For the next few days — or, after castration with clams, from the day when the clams are removed — the animal is walked for a half to one hour daily ; in the country it may be turned out, or put to light work. Exercise favours the escape of discharge, and also tends to prevent the spermatic cord adhering to the skin wound, or the wound itself closing, which is sometimes followed by severe local inflammation and abscess formation. During the first few days after operation it is therefore advisable to cleanse the wound with boiled water or a disinfecting fluid at least once daily, in order to prevent the edges of the scrotal wounds adhering. At a later stage this cleansing process is necessary for the removal of pus, and must therefore be continued until suppuration ceases. Provided no marked swelling or other complication appears, the animal may be returned to light work in from eight to ten days. The most serious consequences of castration are : Bleeding. Apart from trivial skin bleeding haemorrhage is almost entirely confined to cases where the spermatic cord has been twisted, scraped, or torn through, and is very rare after castration with clams. Even after torsion, etc., fatal bleeding is rare. The haemorrhage resulting from division of cutaneous vessels occurs only in drops > CASTRATION — SEQUELAE. 211 is of little importance, and usually ceases spontaneously. Sometimes, however, blood escapes in a fine stream, and the operator's first task is to discover whence it comes. It may discharge from the side of the clam, and is then usually derived from the skin wound or tunica vaginalis ; such bleeding may be readily checked by the use of tampons. Should it originate from the stump of the spermatic cord and discharge below the clam greater care is required, and ligation of the bleeding vessel becomes necessary. The slight bleeding which sometimes follows castration by torsion may be stopped by plugging the scrotum with tampons ; more severe bleeding calls for ligation of the spermatic cord. When the clams are removed bleeding sometimes results from tearing of small veins. Some care is therefore required in their removal ; the best preventive of bleeding is to leave the clams in position for two or three days. As a rule, haemorrhage of this kind ceases spontaneously, but should it persist, the affected side of the scrotum may be plugged with cotton wool or tow moistened with solution of adrenalin. Excessive Swelling of the Scrotum and Sheath. As a rule, severe swelling is due to infection, with retention of discharge, consequent on the edges of the wound adhering, or to the operative wound having been too small. Long rest in the stable also favours retention of discharge and swelling. Should the operator be unskilled in grasping the testicle, he is apt (especially in foals) to make the incision too far back ; the anterior portion of the scrotum then forms a pocket in which discharge accumulates, producing great swelling of the sheath. Exercise both favours discharge and tends to prevent adhesion between the spermatic cord and surrounding tissues, which in itself is a frequent cause of discharge being retained. When unusual swelling occurs, the disinfected ringer should be inserted in the operative wound, and attempts made to secure free exit for discharge. The discharge accumulates more frequently when the spermatic cord is adherent to the edges of the wound, for which reason the spermatic cord is first sought for and the index finger passed round it in order to break down adhesions ; the wound is then rinsed out with a disinfecting fluid, after which the animal is given walking exercise. Infection of the wounds is best avoided by observing the principles of antisepsis. Castration Fever. After castration without antiseptic precautions, trifling fever often appears, even within twenty -four hours. According to Frohner's observations on 190 horses, it occurred in all but 27 per cent. ; 49 per cent, showed moderate, 18 per cent, somewhat P 2 212 COMPLICATIONS AFTER CASTRATION. severe, and 5 per cent, high fever. Fever most frequently appears soon after the clams are removed, especially if this be done within the first two days after castration. Where fever is moderate, the animal should be exercised for half an hour a day. Should the temperature in the horse rise above 103° F., the wound must be carefully examined with the disinfected fingers, any discharge allowed to escape, and the parts washed out with a disinfectant. As a rule the temperature then falls in a lew hours. Septic fever is evidenced by high rise in temperature, frequent pulse, and severe general disturbance. The pulse is not only frequent, but small and weak, and the appetite is usually completely in abeyance, even water being sometimes refused. Not infrequent I \ the castration wound shows no swelling whatever, a symptom which, when associated with high fever, is always serious. On the other hand, severe and widespread swelling, sometimes extending as far as the breast, may occur. Such symptoms call for energetic treat- ment. The most important point is thoroughly to cleanse the wound with a lukewarm disinfectant ; other symptoms must be treated as they arise. Careful attention to cleanliness during operation is the best safeguard against this complication, and it is worth remem- bering that the directions given to the owner regarding the cleansing of the operation wounds are often entirely neglected. Peritonitis. Inflammation of the peritoneum may follow- cas- tration either in consequence of the w-ound being infected, or of discharge being retained. In either case infection is carried upwards by the spermatic cord from the neighbourhood of the scrotum towards and eventually into the peritoneal cavity. High fever, restlessness, abdominal pain, and loss of appetite are the most important symptoms. Treatment consists in thoroughly cleansing the wound and providing for escape of discharge. Should peritonitis follow infection of the wound, the prognosis becomes extremely grave. Prolapse of the cord consists in protrusion of the spermatic cord beyond the wound in the scrotum. It may be caused by dragging on the cord, by applying the clams too low, or by using too heavy clams. Prolapse is not infrequent in weakly animals, especially if the adhesions between the spermatic cord and outer skin be not broken down w'hen the clams are removed. Should the spermatic cord not be soon returned into the scrotal wound or tunica vaginalis a spermatic fistula may result, and is often succeeded by chronic funiculitis or scirrhous cord. CRYPTORCHIDISM. 213 When prolapse accompanies castration with clams, the clams should be removed, and attempts made to release the prolapsed cord and thrust it back again into the scrotum. A strong stream of cold water directed on the parts often results in the cord being retracted. Failing retraction, a clam or ligature should be applied above the prolapsed part. Abscess formation in or about the scrotum results from infection produced by retained discharge. Infection leads to suppurative inflammation of the connective tissue and finally to abscess forma- tion. In this case the swelling is more marked at the spot where the abscess will finally break, and is often hemispherical in shape. Immediately such symptoms are noted, the wound must be examined, and the abscess cavity freely exposed or a counter-opening made. Occasionally it is advantageous to insert a drainage-tube. (6) CRYPTORCHIDISM AND THE CASTRATION OP CRYPTORCHIDS. In the horse and dog, less frequently in other species, the testicles are sometimes either absent or in a state of rudimentary develop- ment. Leisering found the testicles of a stallion, which had in- effectually covered forty mares, almost normal in size, but flabby in texture, wanting the tense normal character. Their arteries were distended, their connective tissue thickened, the semen watery, transparent, and containing many round-cells, but only a few sper- matozoa. Testicles which have been retained in the abdominal cavity often show similar appearances. This condition (retentio testis) is not infrequent in stallions of the coarse, heavy variety, but is also seen in other animals. Leisering and Gurlt found the testicles of a dog still in the abdominal cavity ; Preusser has seen the same thing in pigs, and Kaiser in bulls. Imminger considers the cryptorchid condition is as common in bulls as in horses, and he has been able to establish the hereditary character of the condition in certain cases. This abnormality is termed retentio abdominalis when the testicle lies near the upper wall of the abdomen, retentio iliaca when it is near the inner abdominal ring, and retentio inguinalis when it is within the inguinal canal. The apparent absence of one or both testicles thus produced is termed monorchismus or cryptorchismus. During the first few months of life in the foal the testicles certainly lie in the inguinal canal, but towards the end of the first year they descend into the scrotum. 214 CRYPTORCHIDISM. Gurlt saw a horse in which the testicles occupied a very rare position, viz. in contact with, and adherent to, the diaphragm. Sometimes they lie outside the abdominal cavity, but not in the scrotum (ectopia of the testicle) ; thus the testicles have been found below the diaphragm, or in the crural canal : the first condition is termed ectopia abdominalis, the latter ectopia cruralis. In dogs Moller has found one or both testicles lying beneath the skin next s. CT. T.D. Fig. 244. Section through the walls of the left inguinal canal. The section is through a line drawn from the centre of the lower abdominal ring to the antero-external angle of the ilium. s. Skin. c.t. Connective tissue and fascia beneath the dartos. t.d. Tunica dartos. a.o.a.e. Aponeurosis of the obliquus abdominis ex- bernus muscle, a.l. Anterior lip of the lower abdominal ring. p.l. Posterior lip of the lower abdominal ring. i.e. Inguinal canal and its contained connective tissue, o.a.i. Obliquus abdominis interims muscle. a.t.a. Aponeurosis of the transverse abdominal muscle, p. Peritoneum. p.l. Poupart's ligament, f.t. Fascia of the thigh, c.a. Crural arch. e.i. External angle of the ilium. the glans penis ; in a bull, one testicle was met with in the subcutis of the flank. Supernumerary testicles are said to have been seen in horses and mules. Cox found three testicles in a certain horse, and Oliver as many as four in a mule. The accuracy of these observations may, however, be questioned, as a thorough description of the super- numerary organs is wanting, and one cannot help thinking that these were cases of mistaken diagnosis, CRYPTORCHIDISM. 215 The significance of all these conditions is self-evident. Both anorchidism and defective development of both testicles make the animal useless for stud purposes. The same is usually also true of cryptorchismus, for testicles when retained in the abdominal cavity P.T. L.B. P.V. P.A. Fig. 245. — Transverse section in a perpendicular plane through the pos- terior abdominal region, together with a part of the supralumbar, iliac, and prepubic regions (normal). p.t. Peritoneum, p.a. Branch of prepubic artery, p. v. Branch of prepubic vein, tt.a.k. Upper Abdominal ring. s.c. Spermatic cord. v.d. Vas deferens, p.l. Poupart's ligament, turned downwards, the deep surface visible, l.a. Long adductor of the thigh, l.i.f. Lumbo- iliac fascia, i. Uiacus. p.m. Psoas magnus. t.p.p. Tendon of the psoas parvus, p. Pelvis, r. Rectum, bl. Bladder, l.b. Lateral liga- ments of the bladder with the obliterated umbilical artery, o.a.i. Internal oblique abdominal muscle. c. Cremaster. c.t. Layer of connective tissue which surrounds the upper border of Poupart's ligament, the posterior margin of the internal oblique abdominal muscle, the cremaster, and the peritoneum. are generally atrophic, lax, and either contain degenerated sper- matozoa or none at all ; on the other hand, retained testicles some- times yield abundance of spermatozoa. The question of the fertility of cryptorchids was first raised by Gurlt when studying the function of the spermatozoa ; his experiments seem to deny fertilising power 210 < I : V l'TOKCHIDISM — DIAGNOSIS. under such circumstances, for he was unable to discover spermatozoa in the retained testicle. Since then the same question has been variously answered. Peters considers such animals not fertile, though quite capable of coitus. Wesche, on the other hand, states having seen fertile crypt orchids ; he refers, however, to a case of cryptorchismus inguinalis. A final answer can scarcely be given. The animal's fertility clearly depends on the development of the testicles. The great majority of retained testicles certainly appear degenerated, and contain no spermatozoa. Paugoue speaks of a stallion in which both testicles were retained, and whose progeny numbered amongst them five cryptorchids or monorchids, thus apparently proving the condition to be hereditary. The retained testicle is often the seat of cysts and not infrequently malignant new growths like sarcoma, carcinoma, etc. Leisering, in the case of a dog, found the retained testicle attacked with cancer ; the same condition has been seen in horses. In man, such testicles still more frequently become diseased, so that early removal is generally necessary. The same necessity does not exist in the horse, though removal often becomes desirable on account of sexual excitement (particularly in spring) greatly interfering with the animal's usefulness. Many cryptorchids are too vicious for use. The flesh of cryptorchid swine has usually a repulsive taste, which, according to Koch, is retained even by the salted meat, and is more intense the more completely the testicles have developed. Diagnosis is sometimes very easy, but, on the other hand, is sometimes very difficult ; the exhibition of sexual appetite alone is not a reliable symptom, for ' k rig " horses sometimes behave like geldings and geldings like stallions. Nor is the castration scar to be relied on. The operator may have removed both testicles through one incision, or, as more frequently happens, he may have opened one side of the scrotum without finding the testicle. Cadiot states that where the testicle has really been removed the scar always shows a funnel-shaped depression surrounded with wrinkles. By passing the finger from before backwards along the sheath, a cord, varying in size between a goose-quill and the little finger, can almost always be felt, this represents the stump of the spermatic cord, and can be traced as far as the inguinal ring. On the side of the retained testicle this cord is absent, and instead, one feels a triangular groove. Occasionally the gubernaculum testis is unusually large, and may be mistaken for the stump of the cord, but in such cases the cicatrix is absent. CRYPTORCHIDISM. 217 To distinguish between inguinal and abdominal cryptorchidism Cadiot proposes the following method of examination :— The points of the fingers are brought together, forming a cone, and are pushed towards the inguinal ring : the testicle when in the canal is recog- nised as a rounded, thick, movable object. By examining the inner abdominal ring of either side per rectum there will be found on the side of the retained testicle a thin cord passing into the ring, which cord cannot be caused to move by drawing the sheath downwards. Fig. 246.— A case of abdominal cryptorchidism. T. Testicle, p. Fold of peritoneum surrounding the spermatic cord. v. Vas deferens. R. Rectum. Should the animal have been castrated, however, the cord will descend as soon as the assistant moves the sheath. When the testicle lies in the abdomen the inguinal canal is necessarily empty (unless it contain a loop of the spermatic cord or a portion of the epididymis), and the space usually lined by the tunica vaginalis reflexa is absent. To find the testicle under these circumstances Moller recommends passing the hand into the rectum, and, after first discovering the anterior edge of the os pubis, examining the floor of the abdomen with the outstretched fingers in front of, and for four to six inches on either side of, the linea alba. As a rule, the testicle is soon found ; in other cases the rectum 218 CASTRATION OF CRYPTORCHIDS. requires to be thoroughly emptied and the search renewed. Should the operator be in doubt as to the nature of the body found he may compress it, when, in the event of its being the testicle, the horse usually struggles. Degive passes the hand downwards along the sides of the abdomen to the middle line. Frohner endeavours to draw the testicle backwards towards the pelvic cavity, in order to bring it into a better position for examination. Faecal pellets sometimes mislead the operator, but may be distinguished from the testicle by the fact that they are usually firm and rounded, and may be broken down without causing pain, whilst the testicle is flat, flabby, sharply marginated, very easily displaced, always retains its shape, and is sensitive to pressure. Sand compares the feel of the testicle to that of a small bag filled with mercury. The above examination is only for the purpose of determining whether the testicle is or is not retained, and is of no value for operative purposes, inasmuch as the position of the gland is often entirely altered when the animal is cast. Furthermore, it should not be deferred until immediately before operating, as the soiling of the hands and arms immensely increases the difficulty of properly disinfecting them. The anatomical relations of the parts are very clearly shown in the accompanying figures, redrawn from Cadiot's work. Frohner divides the methods of operation into two, the inguinal and ventral. In the inguinal operation the incision is made a little behind the outer abdominal ring, and extended by blunt dissection towards the inner abdominal ring, in the neighbour- hood of which the abdominal cavity is opened. In the ventral operation laparotomy is performed either in the region of the flank or through the lower wall of the abdomen. Cadiot recommends only castrating such rig horses as are dangerous or difficult to handle, and in other cases abstaining from operation. He considers the beginning of the fourth year the best period, as the descent or partial descent of the testicle often occupies a long time, and when the testicle is only partially developed the inguinal operation proves difficult and sometimes dangerous. The operation demands care and practice, but with antiseptic precautions loses much of its danger, and is often of great service. The operation is easiest in horses which have been kept low for some weeks and are in thin condition, because in them there is less fat in the inguinal region. Some days before operation a dose of physic is given to empty the bowel, and from that time the animal receives only a limited amount of concentrated foool like oats, with a little CRYPTORCHID CASTRATION. 219 hay, but no straw. On the morning of operation the bowel is emptied by a subcutaneous injection of arecolin. Clysters are contra- indicated. Thus prepared, the horse is cast on the side opposite the seat of operation : the hind quarters are half rolled over, and lie somewhat o. \ \ i.e. i.e. o.c. m Fig. 247.— Inguinal canal, viewed from the flank. The external lip of the left inguinal ring has been removed. The aponeurosis of the external oblique abdominal muscle has been cut through a little in front of the spot where it divides. The inner oblique abdominal muscle has been separated from Poupart's ligament to a point near the inner commissure of the inguinal canal. p. Poupart's ligament o.a.i. Obliquus abdominis internus muscle, i.c.i.c. Inner commissure of the inguinal canal, a.o.a.e. Aponeurosis of the obliquus abdominis externus muscle divided and reflected, i.e. Inner commissure of the lower abdominal ring. o.c. Outer commissure, divided, a.l. Anterior lip. p.l. Posterior lip. u.a.k. The dotted line indicates the position of the upper abdominal ring. o. The dotted line indicates the position in which the opening is made in operating for abdominal cryptorchidism. H. Hind limb, adducted. higher than the fore. The upper hind foot is then drawn forward and fixed in position of abduction and flexion, as in ordinary castration. By previously cleansing the hoofs and lower part of the limbs and surrounding them with moist cloths, and by moistening the hair on the upper part of the thigh the seat of operation is protected against dusj; or infection from these parts. 220 CRYPTORCHII) CASTRATION. Some operators prefer to secure the horse in the dorsal or semi- dorsal position, with the hocks well flexed and the thighs held widely separated by means of a rope passed round the croup from one hind limb to the other. This position greatly facilitates operation, especially in cases of abdominal retention of the testicles. Three dishes, each containing 2 or 3 per cent, carbolic solution should be provided. After boiling, the instruments (convex bistoury, artery forceps, and ecraseur), are placed in one and the ligatures and needles in the second ; the third is used by the operator for moistening his hands before exploring the inguinal canal ; in a fourth dish, pledgets of aseptic cotton wool are placed in readiness. The animal having been cast and partly chloroformed, the seat of operation is scrubbed with soap and water, washed with ether, and disinfected with iodine, carbolic, or sublimate solution. The inguinal region, penis, sheath, lower surface of abdomen, and inner surface of the thighs must all be included. The disinfected sheath is plugged with a tampon of cotton avooI. As soon as anaesthesia is well advanced, the assistants holding the dishes place themselves near the operator, who has carefully disinfected his hands and arms and rolled his sleeves above the elbows. The operation is divided into the following stages :— (a) An incision about three or four inches long, parallel with the raphe, is made through the skin and dartos, near the outer inguinal ring or a little forward of the position of the usual castration wound. Care must be taken to avoid wounding the large veins that cross this region ; any bleeding vessels should at once be ligatured or twisted, and blood removed with pledgets of cotton wool. (b) The connective tissue lying between the wound and the entrance to the inguinal canal is torn through with one or two fingers of both hands placed back to back. This process of dilacera- tion is continued down to the external inguinal ring, the posterior commissure of which lies in the angle between the prepubian tendon and the anterior border of the pubis. (c) The index and middle fingers of one hand are then passed into the canal to ascertain if the testicle, epididymis, or any part of the testicular cord is within reach of the hand. Should the testicle be met with at this stage (retentio inguinalis), the operation becomes very simple, being, in fact just like ordinary castration. Sometimes, however, only a more or less short and restricted vaginal sheath, enclosing a loop of the spermatic cord or a portion of the epididymis, can be felt in the inguinal canal. Incision of the sheath with traction on the cord or epididymis may enable the testicle to be withdrawn, CRYPTORCHID CASTRATION. 221 though frequently the sheath is too narrow to permit the passage of the testis, which remains fixed at the inner inguinal ring or within the abdomen. As it is difficult, and even dangerous because of possible rupture, to effect sufficient dilatation of the vaginal sheath, the operator should either disregard its presence or hold it tense with one hand while the other passes to the point where the peritoneal cavity may be entered and the testicle brought through the wound into the inguinal canal. (d) To reach the testicle within the abdomen, the hand, with fingers and thumbs extended and held together in cone shape, is introduced through the external inguinal ring and by semirotary and thrusting movements is gradually passed upwards in the direction of the haunch, occasionally pausing and applying the palmar surface of the fingers to the antero-internal wall, which becomes appreciably thinner as the hand ascends the canal, until only the peritoneum is found separating the hand from the intestines. At this point the abdominal cavity should be entered. (e) A finger is pushed through the peritoneum and the opening is enlarged by carefully introducing a second finger. Perforation is easily made, and if the horse struggle at the moment of puncture the wound may be torn to an alarming extent. Frequently the first object encountered by the fingers on entering the peritoneal cavity is the testicle, which appears to float towards the opening. In other cases the fingers, after searching in every direction, fail to find the testicle or cord, and the hand, and if necessary part of the forearm, must be passed into the abdomen and the search continued. Palpation should be carefully practised while searching, as the testicle may be quite near the hand, but owing to cystic or other abnormality the gland may not at once be recognised. One operator recommends passing the hand towards the bladder, finding the vas deferens, and tracing it back towards the testicle. A hand in the rectum movmg the intestines away from the inguinal region, is often of great assistance to the operator in his efforts to find the testicle ; and in cases attended with much difficulty the effect of altering the position of the horse — as from the lateral to the dorsal position should be tried. Having found the te&ticle, it is drawn through the peritoneal opening into the inguinal canal and removed by the ecraseur. Before tightening the chain, the operator should assure himself that the loop does not include any portion of intestine, which may have passed into the canal with the testicle. If prolapse has occurred, reduction must be effected before the testicular cord is divided. 222 CRYPTORCRTD CASTRATION. In cases of double-sided abdominal cryptorchidism the operation may be performed on each side in succession, or, if the length of the spermatic cords permit, both testicles may be removed through one wound. Usually the scrotal wound is not sutured ; but in certain cases, as when recurrence of prolapse of intestine is feared, the wound may be closed with five to eight silk sutures, powdered with iodoform-tannhi (1-3). and covered with a layer of aseptic cotton- wool, held in place by a suspensory bandage. I.L. M. L. A m\ Fig. 248. — The prepubic and inguinal regions seen from below. (On either side of the middle line is visible the lower abdominal ring and the entrance to the inguinal canal.) I.C.L.A.E. Inner commissure of the lower abdominal ring, o.c.l.a.r. Outer commissure of the lower abdominal ring. i.l. Inner lip. o.L. Outer lip. o.a.i. Obliquus abdominis internus muscle, t. Testicle covered with the tunica vaginalis propria. It has descended as far as the lower abdominal ring (inguinal cryptorchidism), g. Fibrous band repre- senting the gubernaculum testis, l. The dotted line shows the position and direction of the opening made in the obliquus abdominis internus nuiscle when operating by Bang and Moller's method, c.t. Common tendon of the abdominal muscles, p. Section through penis, s. Skin. m. Median line. This completes the operation, and the horse can be allowed to rise. In most cases the after-treatment is similar to that of ordinary castration. The animal may be placed in a clean loose-box and fed sparingly on laxative diet, and after an interval of 24 hours exercised at a walk for twenty minutes twice a day until convalescent. It is seldom necessary to tie the horse up, but when the operation has been a protracted one, the patient may be tied up for four days and kept on half rations, after which it may be allowed to lie down, CRYPTORCHID CASTRATION. 223 still wearing the dressings, which are removed six to eight days later. To diminish the danger of prolapse of the bowel the stall should be higher at the back than at the front, so as to elevate the animal's hind quarters. The tail should be plaited and fastened to one side. Fig. 249. — Transverse section of the posterior abdominal region in a vertical plane. This figure shows the insertion and arrangement of the obliquus abdominis interims and the cremaster. The peritoneum and transverse abdominal muscle have been removed. o.a.i. Obliquus abdominis interims, p.m. Posterior margin of same. c. Upper portion of the cremaster muscle (divided). r.a. Rectus abdominis muscle, l.a.r. The dotted' line shows [the position of the ower abdominal ring, u.a.k. The dotted line indicates the upper abdominal ring. l. The dotted line shows the point at which the hand pierces the peritoneum in the operation for abdominal cryptorchidism, p. Pelvis, p. Rectum, b.l. Bladder. As a rule, little or no pus is formed, but should it appear, the wound must be washed out daily with carbolic, or sublimate solution. Provided fever or loss of appetite is not marked, little after-treatment is necessary, and the animal may return to work in about fourteen days. A loop of intestine may descend after operation. In such case •2-2+ CRYPTOROHID CASTRATION. attempts may first be made to return it by passing the hand into the rectum and exercising traction, but if the intestine has been long exposed the horse should be cast, the gut well disinfected and carefully replaced. Bang sutures the muscular wall of the abdomen or the peritoneum. Peritonitis, when following this operation, is usually rapidly fatal, though occasionally it takes a chronic course of several weeks before death supervenes. Exceptionally a fatal result may arise from haemorrhage from the cord, which after section recedes and bleeds within the abdomen. In perforating the abdominal wall Moller, like Bang, prefers making the puncture through the internal oblique abdominal muscle at the inner wall of the inguinal canal, somewhat nearer the median line than the internal abdominal ring. This produces a " button- hole wound," which does not gape, but, on the contrary, soon comes together again and prevents prolapse of the bowel. A vigorous thrust with the index and middle fingers during inspiration carries them through the abdominal wall into the peritoneal cavity. Different animals, however, present great differences in this respect ; in some perforation is easy, in others it requires considerable force. Finding the testicle or spermatic cord is always the most difficult part of the operation for the unpractised ; nevertheless it can generally be effected with the first two fingers, and without introducing the entire hand. The testicle may easily be mistaken for an empty loop of bowel, but is distinguished by its sharper outline and greater firmness. The end of the epididymis is recognised as a soft mass, containing harder, firmer cords. The spermatic duct can be felt as a hard cord, and is very useful for discovering and drawing forward the testicle, for its size and hardness render it easily recognised. It can, moreover, be brought forward with much less difficulty than the testicle itself, which, when grasped and pulled on, may cause struggling. The object to seek, then, is a very small body, possessing a hard, string-like cord (spermatic cord). By gently pulling on it the testicle is drawn through the opening, though in exceptional cases the testicle may be so large as to offer considerable resistance. Occasionally the testicle cannot be found. Even so skilled an operator as Degive failed in four instances ; Sand relates two, Bayer one or more. Should it prove impossible to withdraw the testicle Degive advises division of the spermatic cord, allowing the testicle to fall back into the abdomen. When the enlargement is cystic Degive brings the testicle near the inguinal ring, thrusts a fine trocar through CRYPTORCHID CASTRATION. 225 the abdominal wall, draws off the fluid, and is then able to pull the collapsed gland into the canal and remove it. Other operators rupture the cysts with the finger and thumb. In one case Moller while searching for the testicle, with the entire hand in the abdominal cavity, discovered a soft body the size of two fists. This he at first took to be the urinary bladder, which on Fig. 250. — Showing positiorTof incision in inguinal operation for cryptorchidism, further examination proved to be in its normal position, whilst the soft body lay near the inner abdominal ring, was movable, and carried at one end a firm object which resembled a testicle. Con- vinced that he had to deal with a degenerated testicle, he extended the opening in the skin and abdominal wall sufficiently far to allow the testicle and spermatic cord to be ligatured. After removing the testicle and suturing both the skin and abdominal wall with strong silk (interrupted sutures), recovery occurred without complication. A closer examination showed that the testicle had almost entirely disappeared, and a cyst containing sixteen ounces of fluid, and having R.S. Q 226 VENTRAL OPERATION ON CRYPTORCHIDS. a circumference of fourteen inches, had formed in the spermatic cord. At the lower end of the cord lay a lipoma, about the size of a duck's egg. and partly ossified. He was inclined to regard this tumour as the degenerated testicle until his attention was directed by Degive, who had seen similar cases in his extensive practice, to hydrocele of the spermatic cord. Degive scratches the hydrocele with the finger-nail until it discharges into the abdominal cavity, when the testicle can easily be removed. Castration of cryptorchid boars is similar to that of horses, with the one exception that a flank incision is preferable. Levens describes a case where the castrator had removed the boar's kidney instead of the testicle, as was discovered on slaughtering the animal. The other kidney had undergone compensatory hypertrophy. The ventral operation can be performed either through the flank or the lower wall of the abdomen. Both methods have been recom- mended, but neither is now much practised. The horse having been cast and placed on its back, the seat of operation is thoroughly cleansed and disinfected. Giinther, who adopted the low operation, made a longitudinal incision of about four to five inches, commencing opposite the free extremity of the sheath and 2 to 2J inches distant from it and passing backwards. This incision exposed the yellow elastic abdominal tunic, which was next incised until the rectus abdominis muscle came in view. The rectus abdominis was partly cut and partly torn through as far as the tendon of the trans versalis abdominis, the fibres of which were divided ; the peritoneum, thus exposed, was penetrated with a sharp thrust with the forefinger. By inserting and spreading out the other ringers the opening in the transverse muscle was sufficiently enlarged in the direction of the muscular fibres to permit of the hand entering easily. The paralysing effect on the arm, due to muscular contraction, which proves so troublesome in certain other methods, was thus prevented. Should difficulty be experienced in finding the testicle Giinther advised passing the hand towards the bladder, discovering the vas deferens, and following it up to its point of origin in the testicle. Another method consists in finding the spermatic artery at its point of origin, and tracing it as far as the testicle. Giinther strongly recommended this mode of operation, but later authorities by no means support him. Frohner condemns it entirely. He lost two out of four horses operated on : one died in consequence of the stump of the spermatic cord protruding between the widely spaced suture in the yellow elastic abdominal tunic and becoming OOPHORECTOMY. 221 infected, thus setting up fatal peritonitis. In the second case the elastic tunic and the skin were very carefully sutured, notwith- standing which a prolapse of bowel occurred on the fourth day. The bowel was thoroughly disinfected and returned, but septic peritonitis occurred and proved fatal. In the next two cases Frohner sutured each layer of tissue separately, firstly the peritoneum, then the rectus abdominis, then the yellow elastic tunic, and finally the skin. Both cases did well. Frohner, however, drew attention to the incon- venience and difficulty of the procedure. Bayer twice successfully operated by this method. (7.) CASTEATION OF FEMALE ANIMALS (OOPHOEECTOMY). The castration of female animals, consisting in removal of the ovaries, is less frequently performed than the corresponding operation in the male. It is said to have certain valuable economic results ; thus young pigs and heifers are thought to fatten more satisfactorily afterwards, and milch cows to remain longer in milk ; bitches are castrated to prevent their breeding, and to avoid the unpleasantness associated with their coming on heat. Cows and sows are the most common subjects of operation, and for this reason will first be considered. (a) Cows not only fatten better, but their milking period is con- siderably prolonged after castration. As early as 1850 Charlier recommended castrating cows thirty to forty days after the birth of the second or third calf, following which the yield of milk was said to remain steady as at the time of castration. Although this expectation has not been entirely realised, cows are still castrated in order to prolong their milk-yielding period, and to increase their capacity for fattening. The operation has been frequently revived and again abandoned. At one time in Germany and Austria it was extensively practised, but later inquiries show that it has been again relinquished, and is now seldom spoken of. Attempts have also been made to practise it extensively in England, but without much success. Even although peritonitis is avoided, the rumen is apt to become adherent to the wall of the abdomen and digestive disturbance to follow. Hendrickx claims that in one respect cas- tration acts as a prophylactic against tuberculosis, inasmuch as it prevents the bearing of calves by animals suffering from or disposed to this disease. Castration is successfully employed in cows as a cure for nympho- mania. Albrecht operated on fifty animals with this object ; forty- two were completely cured, in three cases the operation failed, and Q2 228 CASTRATION. in five cases was only partially successful. After castration the broad uterine ligaments again become tense, the milk secretion and character of the meat improve, and the proportion of fat in the milk increases. At the present time the vaginal method is almost exclusively H. A.W. Fig. 251.— Transverse section of the posterior abdominal region in a vertical plane. The subject is a mare, and the section passes just in front of the first lumbar vertebra. The figure shows the position of the uterus as seen from below and 'that of the ovaries above the broad uterine ligament. o. Ovary, h. Horns of the uterus, u. Uterus, b.it.l. Broad uterine ligament, r. Rectum, a.w. Abdominal wall. p. Pelvis. i.l.v. First lumbar vertebra. employed for mares and milch cows ; but calves, heifers, sows, and bitches, in which the vaginal cavity is too small for this operation, are spayed through the flank, or abdominal floor. To obtain the best results with cows the subjects should have attained their maximum yield of milk and be from five to seven years old. The best period for operation is six weeks to two and a half months after calving. OOPHORECTOMY. 22\ its shape and size. The gland is nipped between the ringers and is then drawn through the incision into the vagina. The ecraseur, with OorJIOKEL'TOMY. 235 Fig. 260. — Scissors for dividing ovarian ligament. Fig. 263.— Metal thumb- stall for scraping through the ovarian ligament. FlG. 262. — Forceps for grasp i ng ovarian ligament in torsion of the ovary. Fig. 261. — Forceps for grasping ovariai ligament in torsion of the ovary. Fig. 264. —Finger clamps for grasp- FlG. 265. — Guarded fus- ing ovarian liga- toury for incising upper ment (Colin). wall of vagina (Colin). 236 CASTRATION. Oi a loop of chain projecting, is next passed into the vagina, and the ovary is slipped through the loop of the ecraseur, which is tightened up until the pedicle is divided. The first ovary when free is left on the vaginal floor, the fingers being again introduced into the peritoneal cavity to secure the second gland, which is removed in precisely the same way. The ovarian pedicles at once return into the abdomen, and the edges of the incised wound come together spontaneously as the vagina contracts. The operator in withdrawing his hand brmgs away the ovaries and knife and any blood clots that may be found on the vaginal floor. Hoffmann describes the antiseptic method. The vulva and neighbouring parts are thoroughly brushed with warm soap and water, warm water is injected into the vagina, and the parts are cleansed with the disinfected hand. After removing the water with the hand or with the help of a rubber tube, Hoffmann rinses out the vagina with a disinfecting fluid, and again washes it with the left hand. The speculum is then passed as far as the os uteri with the same hand, and the right hand, carrying a bistouri cache, being introduced, an incision is made through the upper wall of the vagina. The right hand is then passed through the opening into the peritoneal cavity, the left ovary is found, grasped between the index and middle fingers, and drawn into the vagina, where it is twisted off by means of forceps. The right ovary is removed with the left hand. To prevent straining after operation a pole is passed over the animal's loins. A few hours after the operation the temperature rises to 102-3° F., but falls to normal within the next few days. Should it, however, re- main high, the vagina is washed out with a disinfectant. The vaginal operation may be followed by symp- toms of colic, which are seldom serious, by haemorr- hage, and occasionally by abscess formation and peritonitis. Profuse bleeding during operation is nearly always fatal, the animal dying in a few minutes. This com- plication arises from accidental wounding of the aorta, or one of the iliac vessels when incising the vaginal wall. The pedicle, after OOPHORECTOMY. 2.37 excision of the ovary, may bleed to an alarming extent, and though in some cases compressing the stump with the fingers may arrest the haemorrhage, in others the pedicle must be ligatured. Suppura- tion of the wound and peritonitis arise solely from neglect of antiseptic precautions. Protrusion of intestine through the vaginal wound is a very rare accident. Formerly, when larger incisions were made, hernia occurred frequently. Operation through the flank may be practised in either the standing or recumbent position. Usually the opening is made in the left side, because the rumen, if not too full, is less likely to protrude than the intestine, which is apt to hinder operation through the right flank. The animal is prepared by a restricted diet for thirty-six hours and then secured for operation. The upper region (or hollow) of the left flank is clipped, shaved, washed, and disinfected with iodine, or a five per cent, solution of carbolic acid. In the middle of this space a vertical incision, or one slightly inclined forwards or backwards, and about four inches long, is made through the abdominal wall. The skin, fascia, and muscles are carefully divided layer by layer down to the peritoneum, which is not opened until the bleeding from the muscles has stopped. The peritoneum is punctured with a director and the wound is then enlarged to the same extent as that through the muscles. A hand is passed into the abdomen, over the rumen and downwards towards the right pubic border of the pelvis, to secure the right ovary, which is drawn nearer the opening and removed by the ecraseur. The left ovary is removed in the same way, both glands are brought outside the abdomen, and the cutaneous wound is closed by sutures and covered with a protective adhesive. In opening the flank, some operators endeavour, by dividing the layers of the abdominal wall in different directions, to effect more or less overlapping of the wounds of the skin and muscles, but this object can be more conveniently attained, at least in the recumbent animal, by having the left hind leg drawn well back before incising the flank. (b) Female lambs are seldom castrated. Obich operated on ten- weeks-old animals from the left flank. The incision was sufficiently large to admit the index and middle fingers into the abdomen. The ovaries were drawn towards the opening and were snipped off with scissors. In twelve cases healing was uninterrupted, but in one- lamb an abscess occurred at the point of operation. 238 CASTRATION. Hering castrated six two-year-old sheep from the flank for the purpose of discovering whether the yield of wool would prove greater after operation. In two only the left ovary could be reached. The operation was well borne, though it failed in its object. The animals fattened earlier than their fellows. (c) Mares are castrated for nymphomania associated with vicious- ness, and unilateral castration, removal of the cystic ovary, is sometimes performed in mares which are barren in consequence of ovarian disease. Cadiot has frequently practised this operation, and on the whole has had good results, although in some cases the object, viz. to render Fig. 2C>7. — Ovariotomy with the ecraseur (Cadiot's method). animals quieter and more tractable, has not been attained, a point to which Harms and Thomassen had previously directed attention. In mares, however, castration is always more difficult and more hazardous than in cows. The principal danger consists in the well-known sensitiveness of the horse's peritoneum. The difficulties consist partly in the fact that irritable and well-bred animals can seldom be operated on in the standing position, this only being possible, as a rule, in coarse- bred horses, which can be restrained in a trevis. Furthermore, in the mare the ovaries are much further removed from the vulva, and the ovarian ligament is shorter than in the cow, so that it is impossible to draw the ovaries into the vagina, in order to effect torsion. The operator therefore has to introduce both the hand OOPHORECTOMY. 239 and the instrument into the peritoneal cavity, necessitating a much larger vaginal wound. In the standing position the operation resembles that in the cow. Should a trevis or an operating table not be at hand, the mare, half an hour before operation, should be given a full dose of chloral hydrate and afterwards placed in a stall. The recumbent position is preferable in most cases, and to prevent straining general anaes- thesia is employed. The rectum must be entirely emptied. Hard faeces in the rectum expose the bowel to injury when the vagina is A.W. Fig. 268. — Longitudinal incision in a vertical plane through the posterior abdominal region, pelvis, and urino-genital organs of a cow. The section is somewhat to the right side of the median plane. The figure illus- trates the second stage of ovariotomy : the hand is grasping the left ovary, o. Ovary, u. Uterus, v. Vagina, e.h. Right horn of the uterus (cut through). l.h. Left horn of uterus. b.u.l. Broad uterine ligament. R. Rectum. bl. Bladder, p. Pelvis, a.w. Abdominal wall. e.s. Excavatio superior, e.r. Excavatio recto-vaginalis. e.v. Excavatio vesico-vaginalis. e.i. Excavatio inferior. incised. As in the cow, the vaginal wall is punctured above the os uteri, after preliminary cleansing and disinfection of the vagina, the vulva, and its neighbourhood. The injection of irritating fluids into the vagina must be avoided. Even one per thousand sublimate solution, especially if used warm, may irritate the mucous membrane and cause straining, which hinders operation. The best disinfectant is a cold solution of lysol or carbolic acid, one per cent. The hand carrying the knife is passed into the vagina and directed towards the convex uteri. At first, depending on the degree of anaesthesia, the hand may be closely embraced by the vagina, but by moving the hand to and fro for a few seconds the vaginp 240 CASTRATION. dilates, affording ample space for making the puncture at the proper point — in the middle line of the forward depression between the upper aspect of the cervix and the superior wall of the vagina. After perforating the vagina, the opening is enlarged by inserting and separating the fingers. The hand introduced into the peritoneal cavity traces the uterine horn forwards to its extremity, where the ova*tf lies among the folds of intestine. In mares suffering from nynvJKomania the ovaries are often as large as a duck's egg. They can be distinguished by their firm consistence and their mobility. The left ovary is grasped with the right hand, and the ecraseur having been introduced with the left hand, the chain-loop is passed over the ovary. At this stage the operator must make sure, by feeling with the right hand, that no portion of bowel is included in the loop of the chain. The operator steadies the ecraseur with the left hand, whilst an assistant turns the screw, and so tightens the chain until the ovary is free in the operator's hand. To prevent haemorrhage the screw should be turned slowly — especially towards the close of the crushing process. The detached ovary having been withdrawn into the vagina, the right ovary is removed in a similar way, if necessary the operator's left hand replacing the right, and finally the ovaries and instrument are brought outside and the vagina is carefully disinfected. The patient should be placed in a clean, well-bedded stall or loose-box, and for a few days fed lightly on mash diet. Gradually increasing exercise should be prescribed for ten days and if no symptoms of sickness occur the mare may then be sent to work. In the mare the use of the ecraseur is undoubtedly preferable to torsion of the ovarian ligament with forceps, the risk of injuring the bowel being much less. The ecraseur must be considerably longer and stronger than those used for ordinary castration ; Delamotte uses one twenty -four inches in length. The chain of the ecraseur must also be stronger, otherwise it is very liable to break. Cadiot adopts Colin's method of cutting through the peritoneum, and condemns the suggestion to divide it with the fingers, on account of the serosa dissecting off and forming a pocket. Cadiot's general procedure in the mare resembles that in cows, but he lays special stress on disinfection of the vulva and vagina. The parts are injected and washed with 3 per cent, creolin solution daily for two or three days before operation. He also draws attention to the fact that immediately after operation animals are apt to show colic, which continues from two to four days. He condemns irrigation of the vagina after operation. OOPHORECTOMY. 241 Castration of mares is not often followed by a fatal result, though sometimes owing to accidental wounding of the uterus, or bowel, or to infection conveyed by the hand or instruments peritonitis sets in, causing death within thirty-six hours. Fatal haemorrhage should not occur if the vagina is incised with ordinary care at the proper place. In both mares and cows castration may be followed by chronic inflammation with suppuration of the pelvic connective tissue close to the vaginal wound. This complication arising from infection at the time of, or subsequent to operation, may continue for months, and even prove fatal. Adhesions may also form between the vagina and bowel or wall of the pelvis, and lead to twist of the bowel, with fatal results. Bourges saw a mare die of twisted intestine caused in this way three months after castration. Delamotte reports a case of a mare in which abscess formation followed castration. Luckily the abscess discharged into the vagina and recovery occurred. (d) The castration of the sow is gradually being discontinued. The improved races of swine exhibit sexual appetite to a less degree than the old breeds. They remain on heat for a shorter time, and their fattening suffers little in consequence, so that castration has become more or less superfluous. The operation is usually performed at the age of six to ten weeks — seldom in old breeding sows, although they bear the operation well — but should not be performed while the animal is in oestrum. The best time for castrating old animals is from four to six weeks after parturition. In swine the ovaries hang from the long, flexuous, bowel-like uterine horns, which, at the age of six weeks, are about the size of a goose-quill. The ovaries, small, irregular, and enclosed in a fold of the broad ligament, are situated a little behind the point correspond- ing to the angle of the haunch. It is possible to reach both ovaries through one flank, or by introducing a probe into the uterus and thrusting the organ towards the linea alba to remove the ovaries through the abdominal floor. For this reason two methods of opera- tion are in use, one through the flank and one through the lower wall of the abdomen. The first is practised as follows : — The animal is placed on the right side, and the hind legs are held extended backwards under the operator's left arm by an assistant, whilst the operator presses the animal's head and neck on the ground with his right foot. The knife usually employed has a short broad blade, with a rounded cutting edge, and is unprovided with a spring, so that it can easily be opened or shut with one hand. After clipping away R.S. R 242 CASTRATION OF SOWS. the bristles the primary incision is made in che skin of the left flank, in front of the outer angle of the ilium, in the direction of the external abdominal muscle, or from above downwards and backwards. Other operators make it at right angles to the vertebral column. The opening must be sufficiently large to permit of the index finger being introduced through the abdominal muscles and peritoneum. During an inspiration, or at the moment when the pig squeals, the finger is suddenly thrust through the abdominal tunics, thus preventing the peritoneum dissecting away from the abdominal wall, which would not only render the operation difficult, but might also lead to troublesome sequela?. With the index finger in the abdominal cavity, the operator first secures the left ovary, which is the size of a bean, of firm consistence, and lies nearly equidistant from the external angle of the ilium and the middle line of the sacrum. When the ovary or the uterus is grasped the animal usually squeals, a fact of considerable importance in guiding the operator. The left ovary is drawn outwards and held by the right hand, whilst the index finger and thumb of the left hand gradually bring the left horn of the uterus into the wound, and finally into the right hand. As soon as the point of union of the two uterine horns becomes visible, the operator draws forward the right horn, together with the right ovary, in a similar fashion. Both ovaries are now nipped or torn off, or excised with a knife. In young animals the entire uterus is often removed without bad effect. In older sows only the ovaries are removed, and care must be taken not to draw forward the body of the uterus. The uterine horns are then returned to the peritoneal cavity, the skin wound is sutured, and the animal placed alone in a clean, cool stall. During the ensuing twelve hours it should only receive clean water or small quantities of readily digestible food. Many modifications of these methods have been suggested. In older sows, the abdominal muscles are also cut through, leaving only the peritoneum to be divided with the finger. Should the operator attempt to divide the muscles by means of the finger in such animals, a pocket is formed into which a coil of intestine may pass, become adherent, and cause death, either from peritonitis or from incarceration. In such cases the operator is often erroneously blamed, it being thought that he has sutured the bowel to the abdominal wound. Beginners are advised to perform a few experimental operations in order to gain experience, otherwise they may be unable to find the ovaries. The extreme dexterity which can be attained, however CASTRATION OP BITCHES. 243 is shown by the professional castrator. Bowman, for a wager, castrated 100 sows in 160 minutes. (b) Castration of bitches is performed for the purpose of avoiding in- convenience caused by the animal coming on heat. When young, and not too fat, these animals appear to bear operation well. The manipulation is more difficult than in swine, and can only be mastered by consider- able practice, especially when the operation is performed through the flank. In the bitch, the ovaries lie much further forward, near the kidneys ; they are small, often enveloped in fat and the ovarian ligament is short. The uterine horns are shorter and less flexuous than in the sow. The bitch may be secured like the sow, or may be laid on its right side on a table and anaesthetised. The incision is made near the last rib, and about 11 inches below the transverse processes of the lumbar vertebras. It should be about If inches in length, and should follow the direction of the outer oblique abdominal muscle, which may be divided at the same time as the skin. In the event of the operator desiring to remove both ovaries from one side, which is only practicable in small animals, the incision must not be made too far forward. On the other hand, when an incision is made on either side, each may be placed somewhat further forward. The abdominal wall is pierced with the index finger of the right hand as in swine, and the finger is passed towards the sublumbar region in order to find the ovary, which is the size of a bean, and lies close behind the kidney. Though the ovary may not be found, the horn of the uterus is almost immediately encountered and should be drawn forward, when the ovary will be discovered, and can be nipped or cut off. By utilising the left horn of the uterus, the right may also be drawn forward and the ovary removed in a similar way. Both horns of the uterus are then returned to the peritoneal cavity, and the skin wound is sutured. To prevent the peritoneum stripping away from the abdominal wall and forming a pocket, some operators, after dividing the outer skin and abdominal muscles with a knife, perforate the peritoneum with a director instead of with the finger. The director is then thrust into the abdominal cavity, and the opening enlarged by passing the knife along its groove. This prevents injury to the bowel. It is often difficult to draw forward the right ovary, especially if the incision be made far forward. Some of the most experienced operators recommend making a second incision in a similar position on the right side, and repeating the process. In castration through the abdominal floor, which is easier for beginners, the animal is placed on its back on a table and anaesthetised. 244 CASTRATION OF IUKDS. A long probe, with a slightly bent end, is passed along the upper wall of the vagina into the uterus ; the end is then turned towards the lower abdominal wall, so that its presence can be recognised about 1£ to 2 inches in front of the edge of the os pubis. At this point an incision 1| to 2 inches in length is made close to the linea alba, the peritoneum is pierced with the finger, and with the help of the probe the uterus is discovered ; from this the ovaries are easily found, and can be removed by torsion, or by the knife after ligation of the ligament. The skin wound must be carefully sutured and treated antiseptically. It has been suggested that in young animals a double ligature might be applied close behind the point of bifurcation of the uterus and the organ divided between the two ligatures without the operator troubling to discover the ovaries. Whether this would destroy the sexual appetite or only the repro- ductive powers seems doubtful. Several German veterinary surgeons recommend operating in the linea alba, breaking through the broad uterine ligament, and cutting off the ovaries after ligation with catgut. The abdominal muscles are united with catgut, the skin with silk, and a surgical dressing is applied by means of a bandage passed round the body. The most important complications are fatal bleeding and peri- tonitis. Death from bleeding seldom results after the first twenty- four hours, but peritonitis may prove fatal within a period of from two to ten days. Fatal bleeding is best prevented by ligation of the pedicle, and peritonitis by observing antisepsis, as in all operations that include interference with the peritoneal cavity. (f) Castration of birds consists in dividing the oviduct. The birds are held by an assistant as in caponing, and an incision about f to lj inches in length, and about the same distance from the anus, is made through the abdominal wall. The disinfected forefinger is introduced, the rectum thrust to one side, and the oviduct, which lies below the rectum, and can be recognised by its white colour, is grasped with forceps. The duct is then drawn forward, and cut across with scissors about three quartersof an inch in front of its junction with the rectum. Some operators excise a portion. After returning the ends the wound is sutured as was described in connection with caponing. By slowly exercising pressure on the lower portion of the bird's body the oviduct can be forced outwards through an incision made above the anus. It is then cut through, and the incision sutured. Curing the ensuing three or four days the birds are kept apart in a cool, quiet place, and receive light food. Extirpation of the ovaries is dangerous in hens, and as castration by division of the oviduct is sufficient, oophorectomy is not practised. DISEASES OF THE HEAD. 245 DISEASES OF THE HEAD. I.— DISEASES OF THE LIPS AND CHEEKS. (1.) WOUNDS AND BRUISES. In horses, wounds of the lips frequently result from bites or kicks, from collisions and falls on hard ground, or from entanglement with sharp portions of the harness, or with nails, hooks, etc., fixed in stable racks and mangers. Bruises are produced in a similar manner, and by the severe and repeated application of the twitch. The corners of the mouth may be injured by thin or badly-fitting bits, especially in young and hard-mouthed horses, or in those suffering from brain disease, whilst the cheeks are sometimes lacerated by kicks, horn thrusts, and, on their inner surfaces, by the sharp edges of the molars. Cattle at grass may suffer from torn wounds produced by dogs, while sporting dogs may be bitten by the quarry. The great mobility of the injured parts, and the constant soiling which occurs during mastication, almost always interfere with th) healing of bruises and contused wounds. On the other hand, reparative processes are assisted by the richness of this region in blood-vessels and loose connective tissue, so that healing sometimes takes place by primary intention, even when wounds are extensively bruised, their edges already dry, and their flaps dissected from under- lying tissues over considerable areas. Deep wounds in the corner of the mouth, where the mucous membrane is divided and the opening of the mouth lengthened, give most trouble. Perforating wounds of the cheek also heal with difficulty, and sometimes produce fistula?. Injuries to the great venous plexus in the cheek occasion considerable bleeding, which, however, is seldom dangerous. The division of Stenson's duct often results in salivary fistula. Emphy- sema of the facial region frequently accompanies wounds of the cheek, but calls for no special treatment, and usually disappears spontaneously. Necrosis of the margins of wounds may produce defects in the lips and cheeks, which both injure the animal's appearance and interfere with feeding and drinking. Such defects frequently follow wounds in the corner of the mouth, where the buccal opening becomes lengthened (Makrostomy). 2t