key: cord-1019494-scib6j10
authors: Mehl, Steven C.; Loera, Jackquelin M.; Shah, Sohail R.; Vogel, Adam M.; Fallon, Sara C.; Glover, Chris D.; Monson, Laura A.; Enochs, Joyce A.; Hollier, Larry H.; Lopez, Monica E.
title: Favorable Postoperative Outcomes for Children with COVID-19 Infection Undergoing Surgical Intervention: Experience at a Free-Standing Children's Hospital
date: 2021-01-27
journal: J Pediatr Surg
DOI: 10.1016/j.jpedsurg.2021.01.033
sha: a49ed386431d5dbdfe70bd8ec4e829813a549cc0
doc_id: 1019494
cord_uid: scib6j10

BACKGROUND: Current literature has shown that adult patients with perioperative Coronavirus Disease-2019 (COVID-19) have increased rates of postoperative morbidity and mortality. We hypothesized that children with COVID-19 have favorable postoperative outcomes compared to the reported adult experience. METHODS: We performed a retrospective cohort study for children with a confirmed preoperative COVID-19 diagnosis from April 1(st), 2020 to August 15(th), 2020 at a free-standing children's hospital. Primary outcomes evaluated were postoperative complications, readmissions, reoperations, and mortality within 30 days of operation. Secondary outcomes included hospital resource utilization, hospital length of stay, and postoperative oxygen support. RESULTS: A total of 66 children with preoperative confirmed COVID-19 were evaluated with median age of 9.5 years (interquartile range (IQR) 5-14) with 65% male and 70% Hispanic White. Sixty-five percent of patients had no comorbidities, with abdominal pain identified as the most common preoperative symptom (65%). Twenty-three percent of patients presented with no COVID-19 related symptoms. Eighty-two percent of patients had no preoperative chest imaging and 98% of patients did not receive preoperative oxygen support. General pediatric surgeons performed the majority of procedures (68%) with the most common diagnosis appendicitis (47%). Forty-one percent of patients were discharged the same day as surgery with 9% of patients utilizing postoperative intensive care unit resources and only 5% receiving postoperative invasive mechanical ventilation. Postoperative complications (7%), readmission (6%), and reoperation (6%) were infrequent, with no mortality. CONCLUSION: COVID-19+ children requiring surgery have a favorable postoperative course and short-term outcomes compared to the reported adult experience. TYPE OF STUDY: Prognosis Study. LEVEL OF EVIDENCE: Level IV.

The arrival of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to the United States resulted in a drastic change to our healthcare system as healthcare resources were optimized to deal with the impending pandemic. As our surgical community adapts to these changes, uncertainty remains around perioperative care and potential postoperative complications related to Coronavirus Disease-2019 (COVID- 19) .

The current COVID-19 literature has evaluated surgical outcomes; however, it is limited to adults. [1] [2] [3] By the end of August, approximately 8% of laboratory-verified or clinically confirmed COVID-19 cases occurred in children. [4] Pediatric patients develop similar symptoms as adults with the most prevalent including fever, dyspnea, and cough; however, the disease course is typically milder and death is exceedingly rare. [5, 6] Nevertheless, COVID-19 manifests as a wide spectrum of disease states in children, ranging from asymptomatic infection to multi-system inflammatory syndrome in children in critical cases. [7] [8] [9] Adult surgical patients with COVID-19 have higher rates of surgical mortality, pulmonary and thrombotic complications compared to patients without COVID-19 [1, 3] with few studies evaluating outcomes in children. [10] [11] [12] [13] The possibility of postoperative complications in children with COVID-19 is an important consideration in assessing the risks and benefits of both elective and urgent surgery. The paucity of data regarding the effects of COVID-19 on the pediatric postoperative course has raised questions concerning timing and appropriateness of surgical interventions.

Due to the limited evidence in an evolving COVID-19 environment, policies in surgical care of children are constantly changing. Descriptive studies by Ingram et al. [13, 14] evaluated local pediatric surgical policy changes from 38 well-known North American children's hospitals. Common changes included decreased staff coverage and limitations to work for providers with underlying medical conditions, pregnancy, or > 65 years of age. Similarly, operative management of acute surgical conditions such as appendicitis has been adjusted at some children's hospitals to preserve hospital resources and prepare for a possible COVID-19 surge. [15] Pediatric surgical protocols and procedures continue to change as we improve our understanding of COVID-19 in children. Therefore, the purpose of this study was to describe our institutional experience in the surgical management of children, to briefly describe perioperative protocols and characterize the short-term clinical outcomes in children with COVID-19 who underwent surgery at a free-standing children's hospital. We hypothesized that children with COVID-19 have favorable postoperative outcomes compared to the reported adult experience.

On March 22 nd , Texas Governor Greg Abbott released an executive order directing all licensed health care facilities to postpone all surgeries and procedures not immediately medically necessary, reflecting recommendations from the CDC, the U.S. Surgeon General and the American College of Surgeons [16] . On April 17 th , Governor Abbott issued a new executive order loosening elective surgery restrictions with an essential caveat: the hospital would reserve at least 25% of its hospital capacity for treatment of COVID-19 patients. As the state of Texas began to reopen with increasing laxity towards social restrictions, the Texas Medical Center in Houston experienced a surge of COVID-19 cases with a peak of 2,962 new cases on July 14 th . [17] We performed a retrospective cohort study at Texas Children's Hospital, a freestanding children's hospital with two community campuses, in Houston, TX. After IRB approval (H-48227), we reviewed surgical cases for children 18 years of age who had surgery from April 1 st to August 14 th 2020. We identified 73 patients who underwent a surgical procedure and had perioperative SARS-CoV-2 RT PCR positive test results.

Two patients were excluded who initially presented with COVID-19 pneumonia, receiving invasive mechanical ventilation with eventual transition to either venoarterial or venovenous extracorporeal membrane oxygenation. Five additional patients were excluded with initial negative preoperative surveillance test, and subsequent positive test results during their hospitalization within 4 days of surgery. On institutional review of their contact history, these patients were likely in the early incubation period at the time of their initial presentation and were felt to be in a different time course of their COVID-19 infection relative to those with confirmed preoperative COVID-19. The preoperative diagnoses were thigh abscess, septic arthritis, gram negative bacteremia, and obesity with respective surgical procedures including incision and drainage, incision and drainage, central line removal, and elective sleeve gastrectomy. The patient who underwent sleeve gastrectomy had a diagnostic laparoscopy on postoperative day 3 due to persistent fever to rule out staple line leak. The fever was determined to be secondary to COVID-19 following negative laparoscopy and confirmatory test. No patients experienced significant postoperative complications. Preoperative, intraoperative, and postoperative data were collected. Preoperative data included age, sex, race, ethnicity, weight, body mass index (BMI), ASA class, comorbidities, surgical diagnosis, preoperative symptoms, preoperative laboratory assessment, preoperative chest imaging, and preoperative respiratory support. Operative data included surgical specialty, surgical procedure, Analyses were performed using Stata version 16 (StataCorp, College Station, TX).

We drafted guidelines for classification of elective and urgent surgeries while conforming to state-wide mandates and recommendations from national health organizations and surgical societies. [16, 18] Our guidelines have continued to evolve over the course of the pandemic with Figure 1 highlighting various components in effect in early April 2020.

Preoperative test with SARS-CoV-2 RT PCR nasopharyngeal swab was performed for all patients undergoing surgery. In life-threatening and emergent cases, the patient was treated as a "Patient Under Investigation" (PUI) and taken to the operating room within the appropriate time period prior to final test results. For urgent, semiurgent, and non-urgent surgical cases, the preoperative test is resulted prior to proceeding to the operating room.

All elective, outpatient cases received surveillance testing within 3 days prior to the surgical procedure. This is performed through our institution at a predetermined campus via drive-through stations. Following surveillance testing the patient and family members quarantined until the day of surgery. If the preoperative surveillance results were positive, elective procedures were classified by the attending surgeon as medically necessary or elective, respectively causing cases to proceed or defer.

All providers and visitors were screened upon arrival to our institution with a brief symptom survey and temperature check. While in the hospital, surgical masks were mandatory. Only one parent or guardian was allowed to stay with the child in the hospital. Perioperative protocols were developed regarding operating room preparation, patient transportation, and operating room cleaning. All operating room staff was required to complete personal protective equipment (PPE) training. Postoperative cleaning was completed after a 30 minute wait time to allow for dissipation of possible aerosolized SARS-CoV-2.

We set up multiple precautions to limit exposure through the perioperative process guided by recommendations from the Anesthesia Patient Safety Foundation [19] and the American Society of Anesthesiologists [20] . These recommendations are based on previous Centers for Disease Control and Prevention experience with SARS-CoV and Middle Eastern respiratory syndrome coronavirus. [21, 22] Environmental adaptation included limiting family members and transporting patients directly to and from the operating room with a universal masking policy. Workflow adaptations included reinforcing frequent hand hygiene and proper donning and doffing of PPE. All providers used N-95 respirators, goggles, gloves, and gowns during intubation and care of COVID-19+ patients. Personnel was limited during airway manipulation. Rapid sequence induction was used to secure the airway with goals of securing the airway centered on rapid placement of an endotracheal tube (ETT) and elimination of aerosolization or secretions during intubation. Placement of an ETT was immediately followed with clamping the ETT and attachment to either an electrostatic filter or a high quality Heat and Moisture Exchanging Filter, capable of removing >99.97% of airborne particles >0.3 microns, between the Y-piece of the breathing circuit prior to instituting ventilator support. Extubation was performed deep and with limited staff to mitigate aerosolization exposure. Extubation was immediately followed by placement of a surgical mask with recovery occurring in the operating room prior to their final disposition.

Our institution has continued to perform minimally invasive procedures. During a surgical procedure for a PUI or COVID-19+ patient, all providers are required to wear PPE, including eye protection and N-95 respirators. Disposable insufflation cables and trocars are utilized. A closed smoke evacuation system is used for CO 2 evacuation and electrocautery. The operating surgeon aims to limit "leaking" of CO 2 through trocars, and utilizes low-power electrocautery at their discretion. Aspiration of residual CO 2 is performed at the conclusion of the operation via the closed filter system.

Same Day discharge has continued to be utilized for appropriate cases. To limit exposure in the post-anesthesia care unit at the beginning of the pandemic, patients were discharged directly from the operating room after extubation, recovery, and re-evaluation by the surgical team. However, patients are now transferred to an isolation room in postanesthesia care unit and discharged from the post-anesthesia care unit after recovery.

All patients that require postoperative hospitalization are transferred from the operating room to an isolation unit. The isolation unit limits provider exposure and all rooms have necessary isolation precautions and PPE. Following admission, the pediatric hematology team is consulted to evaluate the patient for postoperative prophylactic anticoagulation. Daily laboratory monitoring is performed with CBC with differential, DIC panel (PT, aPTT, PTT hepzyme, thrombin time, fibrinogen, D-dimer), and Creactive protein during hospitalization to assess changes in thromboembolic risk. The patient is evaluated for > 1 of the following risk factors: decreased mobility, obesity, D-Dimer > 2 times the upper limit of normal, and laboratory evidence of ongoing inflammation with C-reactive protein and Fibrinogen. Based on patient risk factors and daily labs, the hematology team makes final recommendations for postoperative prophylactic anticoagulation. Once all surgical discharge criteria are met, patients are discharged directly from the isolation unit.

A total of 66 patients underwent surgery with a preoperative positive SARS-CoV-2 RT PCR. The median age of patients was 9.5 years (IQR 5 -14) with 65% male, and 70% Hispanic White ( Table 1 ). The median weight and BMI were 41.6 kg (IQR 21.6 -63.8) and 21.5 kg/m 2 (IQR 17.0 -26.2), respectively. Ninety-one percent of patients initially presented to the emergency room, with only 9% of patients presenting for elective procedures. Half of the elective cases (3/6) were oncologic cases (retinoblastoma, osteosarcoma x2) with the remaining cases requiring surgery due to progressive pathology. Sixty-five percent of patients had 0 comorbidities with only 5% of patients having two or more comorbidities. The most common comorbidities were obesity (9%) and pulmonary/prematurity (8%) ( Table 1) . The most common preoperative symptom was abdominal pain (65%) and the least common was dyspnea (0%), with 23% of patients having no COVID-19 related symptoms ( Table 1) . Symptoms were further stratified by operating surgical specialty and surgical diagnosis (Figure 2) . General surgical patients presented significantly more often with abdominal pain (general surgeon 87%; other surgical specialties 19%; p = 0.0001) and nausea/vomiting (general surgeon 69%; other surgical specialties 14%; p = 0.0001 (Figure 2A) . Conversely, all other surgical specialty patients presented significantly more often with no COVID-19 related symptoms (general surgeon 5%; other surgical specialties 57%; p =0.0001) (Figure 2A) .

Similarly, patients with gastrointestinal pathology presented significantly more often with abdominal pain (gastrointestinal 91%; soft tissue infection/extremity fracture 0%; "Other" 33%; p=0.0001) and nausea/vomiting (gastrointestinal 72%; soft tissue infection/extremity fracture 9%; "Other" 17%; p = 0.0001). Patients with a soft tissue abscess or extremity fracture presented significantly more often with no COVID-19 related symptoms (gastrointestinal 2%; soft tissue infection/extremity fracture 82%; "Other" 42%; p=0.0001) ( Figure 2B) . The most common preoperative laboratory assessment performed was complete blood count in 45 patients with median values indicating mild leukocytosis (11.7 (IQR 8.9 -16.1), lymphopenia (16.5 (IQR 6.4 -30.8)), and normal platelet count (260 (IQR 217 -372). A substantial majority of patients had no preoperative chest imaging (82%) with abnormal chest X-ray (2%) and abnormal thoracic computed tomography (3%) in a minority of patients. Preoperative respiratory support was utilized for a single patient by non-invasive nasal cannula (1-2 Liters/minute) which was used at baseline for pre-existing chronic lung disease.

The most common operating surgical specialty was general pediatric surgery (68%) followed by orthopedic surgery (11%) with all remaining specialties performing 4 cases ( Table 2) . Appendicitis was the most common diagnosis (47%) with uncomplicated appendicitis occurring almost three times as often as complicated appendicitis. After appendicitis, the most common diagnoses were extremity fracture (9%) and soft tissue abscess/foreign body (8%) with all other diagnoses representing 3 cases ( Table 2) . Reflective of the surgical diagnoses, laparoscopic appendectomy (47%), laparotomy (11%), extremity fracture fixation (9%), and soft tissue incision and drainage or foreign body removal (8%) were the most common procedures performed ( Table 2) .

Abdominal minimally invasive surgery was the most common type of surgical intervention at 52% ( Table 2) Forty-one percent of all patients underwent same day discharge and only 9% utilized ICU resources ( Table 3) . Fifty-nine percent (16/27) of the same day discharges were patients with uncomplicated appendicitis. Fifty percent of patients were admitted to an isolation unit utilizing resources common to a postoperative acute care floor. Nightytwo percent of patients did not receive any postoperative oxygen support, and only 5% received postoperative mechanical ventilation ( Table 3) . All patients who received postoperative invasive mechanical ventilation were extubated within 48 hours.

Postoperative prophylactic anticoagulation was initiated in 17% of all patients and 28% (11/39) of hospitalized patients ( Table 3) . The median hospital length of stay was 2 days (IQR 1 -4 days). Postoperative complications occurred in 5 patients (7%). These complications included two intra-abdominal abscesses after complicated appendicitis, wound dehiscence after excision of a thigh sarcoma, small bowel obstruction after an enterectomy for blunt abdominal trauma, and upper extremity seroma after osteosarcoma resection. Readmission occurred in 4 patients (6%), which included two intra-abdominal abscesses, wound dehiscence, and small bowel obstruction, as mentioned above.

Reoperation occurred in 4 patients (6%), which included 2 percutaneous drain placements for intra-abdominal abscesses, complex wound closure after wound dehiscence, and diagnostic laparoscopy converted to laparotomy following small bowel obstruction.

There were no postoperative deaths.

COVID-19+ children undergoing surgery at a free-standing children's hospital in the 4 th largest metropolitan area in the nation presented primarily with general surgery pathology with postoperative complications and mortality occurring less frequently than the adult population. [1, 3] A majority of our patients were Hispanic White males > 6 years of age without comorbidities. Compared to similar pediatric cohort studies in the United States, our results show COVID-19 occurred more frequently in the Hispanic population. [5, 8, 9] Less than 10% of patients were <1 year old with pyloric stenosis diagnosed for 3/5 patients. Additionally, a majority of our patients were previously healthy without any significant pulmonary symptoms at presentation with <10% of patients with pre-existing cardiopulmonary disease. Therefore, these findings may not be represented <10% of patients in our cohort. Over our study period >100 elective cases were cancelled due to positive preoperative results. Surgeons proceeded with cases based on both surgeon preference with approval from operative leadership and our operative classification system (Figure 1) . Preoperative laboratory testing was primarily limited to complete blood count with the most notable finding of lymphopenia, a known lab abnormality related to COVID-19. [29, 30] Pediatric general and orthopedic surgeons performed a majority of all surgical cases. The most common surgical pathologies were appendicitis, extremity fractures, and soft tissue abscess or foreign bodies, while the most common procedures were laparoscopic appendectomy, laparotomy, incision and drainage of soft tissue abscesses, and extremity fracture fixation. Uncomplicated appendicitis was diagnosed almost three times as often as complicated appendicitis. We had expected worsened disease severity for all appendicitis patients during the pandemic secondary to delayed presentation due to reluctance to seek medical care, as evidenced in recent reports. [31] However, the proportion of simple versus complicated appendicitis did not differ from historical institutional trends at the population level. Prior to the pandemic, the nonoperative success rate of appendicitis in the pediatric population has ranged from 62 -76%. [32] [33] [34] [35] Several authors have described performing nonoperative management of appendicitis during the current pandemic. [36, 37] Kvasnovsky et al. reported over half of all appendicitis cases failed initial nonoperative management, which was defined as persistence of pain, fever, or emesis after 12 -24 hours. [36] Of the 30 patients undergoing surgical intervention, over half were diagnosed with uncomplicated appendicitis. The authors explain the reason for their lower success rate was due to the majority of patients not meeting published guidelines for nonoperative management and the need for prompt decision-making to proceed with surgery if nonoperative management appeared to be failing within 12 -24 hours of admission to preserve available hospital resources. Ultimately, if hospital resources are not significantly strained at a given institution, our results suggest initial surgical intervention can be considered. An additional negative consequence of possibly delaying surgical intervention is increasing length of stay; however, Kvasnovsky et al. showed that initial failed nonoperative management only increased median length of stay by approximately 6 hours. [36] At our institution, we continued surgical care for appendicitis with emphasis on same day discharge from the recovery room to decrease hospital length of stay.

Another concern in the surgical community during the COVID-19 pandemic is possible provider contraction of SARS-CoV-2 during aerosol generating procedures (AGP), specifically laparoscopic procedures. Anecdotally, some institutions have resorted to performing common minimally invasive procedures, such as appendectomy and pyloromyotomy, via open approach to eliminate the risk associated with AGP. The European Society of Pediatric Endoscopic Surgeons published guideline recommendations related to minimal invasive surgery, which we incorporated in our perioperative care protocol, such as utilizing closed-system CO 2 insufflation and limiting use of laparoscopic electrocautery [38] . An advantage of continuing to perform minimally invasive surgery when feasible is to minimize hospital length of stay for COVID-19+ patients. In our cohort, patients undergoing abdominal minimally invasive surgery had an expected shorter hospital length of stay compared to open abdominal surgery. Similarly, performing minimally invasive can allow for same day discharge, as was possible for > 40% of our COVID-19+ patients. An additional recommendation for AGP is limiting the time period of aerosolization. Only three surgical pathologies were treated laparoscopically: appendicitis, pyloric stenosis, and ovarian torsion, which collectively had median surgical time <40 minutes. However, a counterargument can be made to defer interventions if patients require a prolonged hospital length of stay to reserve hospital resources and potentially protect providers from possible contraction.

Ensuring provider safety is of paramount importance when creating and implementing triage/classification algorithms to guide surgical decision-making and its timing. Our classification system (Figure 1 ) was implemented in the spirit of delivering necessary care and to do so while protecting providers. Many factors play a role including the type of surgery and expected postoperative resource utilization. Nevertheless, a key element is the robustness of PPE supply as one category to minimize provider exposure risk for those urgent/medically necessary surgeries that must proceed. We believe that with appropriate AGP protocols and robust surgical PPE supply the benefits of minimally invasive surgery with respect to resource utilization, provider safety, and patient care outweigh the risks.

Several adult single center studies and case series have identified increased postoperative morbidity and mortality secondary to COVID-19. [1] [2] [3] Postoperative morbidity is primarily related to cardiac and pulmonary complications with some studies reporting 50% of patients experience postoperative pulmonary complications with a wide range of postoperative mortality from 24% -75%. [1] [2] [3] There is currently limited evidence suggesting whether similar postoperative morbidity and mortality occurs in children undergoing surgery. [10] [11] [12] [13] Our results highlight a substantially smaller proportion of children required postoperative ICU resources compared to adults. Of the six patients requiring ICU resources, three patients required postoperative mechanical ventilation with extubation to room air or nasal cannula within 48 hours. Of these three patients, only one required preoperative oxygen support with nasal cannula; however, this was the patient's baseline respiratory support due to pre-existing lung disease.

Interestingly, none of these patients had significant pulmonary symptoms at presentation, and the decision for postoperative mechanical ventilation was made based on intraoperative findings and concern for potential worsening respiratory status after surgery. The remaining three patients were admitted to the ICU for hemodynamic monitoring and resuscitation with either blood products (oncologic patient with pancytopenia who presented with hematochezia secondary to ileocolic intussusception) or crystalloid (septic shock secondary to complicated appendicitis) without the need for vasopressors. Therefore, the ICU admission for only half of the patients was primarily literature has identified two additional concerning pathologies: a hypercoagulable state [39] [40] [41] [42] and multi inflammatory syndrome in children [8, 9] . Our study is limited as a single center review; however, it is the first study evaluating postoperative outcomes of children with SARS-CoV-2 requiring surgical care.

Also, a majority of our patients were healthy children with minimal pulmonary symptoms, limiting generalizability to pediatric patients with significant comorbidities or pulmonary symptoms. Future multi-institutional studies will need to be performed to 

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