key: cord-0426896-w2yeo78c
authors: Durrance, Richard J.; D'Souza, Kenneth G.; Obata, Reiichiro; Bradley, Ellen C.; Perwaiz, Muhammad K.
title: Endobronchial blood-patch: A novel technique for a persistent pleural air leak
date: 2022-05-28
journal: nan
DOI: 10.1016/j.rmcr.2022.101670
sha: ffb9ca45dfecf649998a739881142dd3cd2c7a13
doc_id: 426896
cord_uid: w2yeo78c

Introduction Patients with severe COVID-19 Pneumonia requiring prolonged mechanical ventilation have an increased incidence of pneumothorax. Mechanically ventilated patients who are critically ill and develop a persistent air leak from pneumothorax are poor candidates for surgical repair. As the persistent air leak can be a significant barrier to vent-weaning and clinical stability, these patients present a unique clinical challenge. Clinical case A 65-year-old male intubated and on prolonged mechanical ventilation for severe COVID-19 Pneumonia developed a pneumothorax complicated by a persistent alveolar-pleural fistula with a persistent air-leak. Given his critical state with ongoing pressor requirements and elevated vent requirements, surgical repair was not an option. A bedside bronchoscopy occlusion study with isolation of the air leak, and subsequent autologous endobronchial blood-patch repair with thrombin was performed with rapid and definitive resolution of the air leak. The patient progressed favorably, ultimately being weaned from the ventilator, decannulated, and walking out of the hospital. Conclusion In critically ill ventilated patients with pneumothorax complicated by a persistent air-leak, bedside endobronchial evaluation and blood-patch repair is a feasible approach to management.

challenge. These patients are often critically ill with a dynamic clinical course that generally precludes 56 repair by surgical intervention. In addition, the persistent air leak can pose a significant hurdle to the 57 ventilator-weaning process.

Patients with severe COVID-19 infection requiring mechanical ventilation have been observed to have a 60 relatively increased incidence of barotrauma [1] . As the subset of these patients who require prolonged 

Five days later he developed a tension pneumothorax on the right side, which was successfully treated 84 first with needle-decompression, and subsequent placement of a small-bore chest tube. He 85 demonstrated a persistent continuous air-leak on suction and water seal. His clinical course was 86 complicated by an ipsilateral hemothorax, for which a surgical chest tube was placed, and underwent 87 arterial embolization of the right internal mammary artery for hemostatic control ( Figure 1A ).

Given the fact that the patient remained on vasopressor support with persistent rapid atrial fibrillation, 90 interdisciplinary evaluation with the thoracic surgery service concluded that the risk of surgical 91 intervention was determined to be unacceptable. Therefore, after 14 days of unsuccessful resolution via 92 chest tube drain, endobronchial treatment was pursued. Endobronchial valves required either IRB 93 approval or humanitarian exemption, a process which could take up to 3-5 days. Therefore, autologous 94 endobronchial blood patch repair was considered, and appropriate humanitarian exemption paperwork 95 was completed in accordance with the scope of the procedure.

Occlusion study: 98 J o u r n a l P r e -p r o o f

One key aspect of endobronchial treatment of a persistent APF is air leak localization and the determination that collateral ventilation is not present via high-resolution CT chest imaging. However, 100 given the significant parenchymal compromise evident on imaging (Figure 1 A and B) , an adequate 101 evaluation of fissure integrity was not reliable. Furthermore, the location of the air leak was not obvious 102 on the CT imaging done (Figure 1 A and B) . For this reason, an occlusion-study approach was determined 103 to be most feasible and practical option to leak localization determination of potential resolution.

The patient was first subjected to a bedside bronchoscopic occlusion study. In order to keep the patient 106 still, fentanyl and midazolam were administered to assure passive compliance with the ventilator. The 107 pleural drain was maintained to continuous suction at 20cm H20, with a constant 1-column air leak 108 appreciated. An 80cm 5Fr Fogarty catheter was utilized under bronchoscopic guidance, with sequential 109 apical-to-caudal segmental occlusion. Occlusion of the lateral segment of the right middle-lobe (B4) 110 resulted in rapid air leak cessation on the pleural drain ( Figure 2 ). The air leak quickly re-appeared after 111 removing occlusion from the segment. No change in air leak was observed with occlusion of any other 112 segment, and therefore the persistent Broncho-pleural fistula was isolated to the B5 segment.

Blood-Patch:

The blood-patch was performed as a separate procedure. As before, the patient was sedated to passive 117 compliance with the ventilator. Rocuronium was used as a paralytic in this instance to assure no 118 inadvertent movement (i.e., cough) during the blood-patch procedure itself. After bronchoscopic 119 inspection, we performed occlusion of the B4 segment of the Right Middle Lobe, reconfirming the 120 location of the air leak location (again with the pleural drain to 20cm H20 negative pressure). The Swan-121 Ganz catheter was used in this instance in order to assure satisfactory occlusion prior to performing the 122 blood-patch portion of the procedure.

Under sterile conditions, 30cc of autologous blood was removed from the patient. With the Swan-Ganz 125 catheter through the therapeutic scope the previously identified B4 segment with the balloon inflated, 126 the 30cc of autologous blood was then injected into the B4 segment, followed by two injections of 5000 127 U of reconstituted Thrombin (10cc solution total), for a total of 40cc fluid. Occlusion was maintained for 128 3 minutes under direct visualization, during which time no fluid was appreciated escaping the occluded premise for which this is done is based on the fact that whole blood contains both platelets and clotting off" the area over which it is applied. In difference to the epidural space in which a low-pressure and 152 low-flow leak occurs, an alveolar-pleural fistula is a much more dynamic leak. In every breath, the 153 transpulmonary pressure will stress the leak towards the pleural space on inspiration and away from the 154 pleural space on exhalation. In order to facilitate rapid closure of the APF, the following steps were 

In critically ill patients with persistent alveolar-pleural fistulas, the absence of resolution poses a 181 significant barrier to recovery. This is especially true in the COVID-19 era, in which there has been an 182 increase in the number of patients with chronic respiratory failure. Therefore, we do not pretend to 183 propose an alternative to standard of care therapy for those who are surgical candidates. In recognizing 184 the limitations that critically ill patients possess, we seek to share our experience as a feasible and safe 185 alternative approach to a complex clinical problem.

Secondly, one could argue that by virtue of the presence of a hemothorax, the patient effectively failed 188 pleural blood-patch therapy. This would suggest that the endobronchial approach to autologous blood-189 patch repair could potentially have better efficacy than the pleural blood-patch procedure, quoted as 190 85% in one review [8]. 191 192 Conclusion: 193 194 J o u r n a l P r e -p r o o f As the endobronchial blood-patch repair of a persistent alveolar-pleural fistula can be done at bedside under sterile conditions if necessary, it greatly enhances the pulmonary-critical care approach to 196 resolution of this clinical problem, and has the potential to significantly improve patient outcomes. Figure 1 : CT Chest Axial and Coronal views pre-(A and B) and post-(C and D) blood-patch repair. The red arrow in Image A indicates the distal end of the surgical chest tube in the prerepair image.

Patients With ARDS on Invasive and Non-Invasive Positive Pressure Ventilation

Valve Placement and Liberation from Mechanical Ventilation in Acute Respiratory Distress 204

Syndrome: A Case Series

Complications after bronchoscopic lung volume reduction

Endobronchial blood patch with thrombin 209 injection

Surgical Factors Influencing Air Leak After Lung Volume Reduction Surgery: Lessons Learned From 212 the National Emphysema Treatment Trial

Incidence and Risk 215 Factors of Persistent Air Leak After Major Pulmonary Resection and Use of Chemical Pleurodesis

Endobronchial Autologous Blood Patch and Spigot Occlusion: A Multicentre Randomized 219

Blood patch for persistent air leak: A review of the current 221 literature. Current Opinion in Pulmonary Medicine

Bronchoscopic management of prolonged air leak

Bronchoscopic Blood Patch for Treatment of 226

Persistent Alveolar-Pleural Fistula

A new interventional bronchoscopy technique for the treatment of bronchopleural