Things are not always what they seem: A rare and serious complication in a child on veno-venous ECMO ABSTRACT: Introduction: ECMO-related complications may conceal serious underlying problems. Case report: A 22 month-old male patient was put on veno-venous ECMO for respiratory failure using a 19 French dual-lumen cannula, with an additional cannula in the iliac vein to optimize drainage. Following the development of abdominal distention, a peritoneal tap returned fresh venous blood. Iliac vein perforation by the cannula was suspected. Urgent laparotomy revealed against all odds, a perforated duodenum, which was primarily repaired. Discussion: The management of vessel perforation by the ECMO cannula is a nightmare: Limited cannulation sites; hemodynamic instability; Cessation of anticoagulation; massive transfusions; transfer to radiology for a CT scan. These concerns may divert the attention from other serious underlying complications. Conclusion: With increasing use of ECMO, more attention should be given to rare complications related to the underlying diseases. This is the first reported case of a duodenal perforation in a child on ECMO. Introduction: Extracorporeal membrane oxygenation (ECMO) is a method of supporting the heart and or the lungs while native organ function recovers. During the last 2 decades, the role of veno-venous (VV) ECMO for refractory respiratory failure in the pediatric population has been established as a lifesaving technique (1). However, despite extraordinary technical progress, ECMO-related complications remain a real concern in 40% of the cases (1,2). Common complications include bleeding, infection, and thromboembolic events (2,3). Less common complications include the dislodgment of a cannula, or the perforation of a cannulated vessel (2-4). Critically ill children may also present unique complications rarely encountered in the current era; a perforated bleeding duodenal ulcer is a rare occurrence in modern day medicine (5).This potentially fatal complication may present insidiously, especially when all fingers point at the cannulas in a patient on ECMO. To the best of our knowledge, this is the first reported case of a duodenal perforation in a child on ECMO. Case: A 22 month-old boy was transferred to our institution after 17 days in ICU for acute respiratory failure secondary to H1N1 infection. V-V ECMO was initiated using a 19 French dual lumen cannula. Suboptimal venous drainage necessitated the insertion of a second drainage cannula, ideally in the inferior vena cava. The only available short 14 French cannula didn’t reach the vena cava, and was positioned in the iliac vein. Despite appropriate support with ECMO, the patient remained critical with borderline vital signs and urine output. There were no signs of infection; he was on broad spectrum antibiotic therapy, antiviral treatment with oseltamivir, total parenteral nutrition, and gastric protection with ezomeprazole. Laboratory work including chemistries, coagulation parameters, and urinalysis were all within normal limits. All ttempts at enteral nutrition were not tolerated. On ECMO day 5, the patient started developing increasing abdominal distension, with significant ascitis on ultrasound. A drop in hemoglobin from 9.8 to 8.0 g/dl was attributed to circuit hemolysis. Ultrasound guided peritoneal tap returned 900 ml of fresh venous blood, and continued draining fresh blood. Injury to the iliac vein by the inappropriate venous cannula was immediately suspected. Although the patient was hemodynamically stable, it was deemed risky to waste time performing a CT scan, and he was taken directly to the operating room. The femoral cannula was removed but no perforation was identified. Tracking the source of bleeding lead to the right upper abdominal quadrant. Hepatic vein injury from the tip of the dual lumen cannula was then suspected, but no perforation was found. Further dissection revealed some bile efflux from an area involving the transverse colon and the duodenum. The exploration of this inflammatory and fibrous area exposed a 1cm perforation (figure 1A) involving the first portion of the duodenum. The aspect of the surrounding necrotic tissues was suggestive of chronicity. The perforation was closed and reenforced with an omental patch. The post-operative course was uneventful, and ECMO support was continued using the initially inserted dual-lumen cannula for 34 days. The child is currently going through rehabilitation physical therapy. Because of the chronic aspect of the perforation, we retrieved the abdominal x-rays taken upon arrival to the hospital, and discovered a large pneumoperitoneum (figure 1B). Discussion: Even though survival rates are improving, the journey while on ECMO is fraught with complications. The most common complications for pediatric patients on VV ECMO include cannula-related bleeding 16%, other cannula-related problems 15%, culture-proven infections 10.3%, cerebral hemorrhage 7%, and gastro-intestinal hemorrhage 4.9% (1,2).Few studies discussed cannula related perforations, reporting percentages reaching 2% (3,4,6). In addition to being an emergency, it is a dreaded complication and its management is a nightmare: Limited alternative cannulation sites; hemodynamic instability; Cessation of anticoagulation; massive transfusions needs, adding to lung injury; transfer of a critically ill, bleeding patient on ECMO for a CT scan; and the need for urgent surgery. We decided to avoid this series of challenges by operating before hemodynamic instability, with the presumed diagnosis of vessel perforation. Our diagnosis proved to be incorrect, but all intensivists and surgeons with ECMO expertise didn’t regret this decision. Senior intensivists and non-cardiac pediatric surgeons considered for a moment a gastrointestinal cause for the bleeding, but were overwhelmed by the prevailing diagnosis of vessel perforation and its potential consequences. Perforated peptic ulcer in children is a rare cause of acute abdomen today, due to the decreased prevalence of Helicobacter Pylori, and the improved efficacy of proton pump inhibitors (5). While the literature about this disease is outdated in western countries, it is still reported in developing nations, most cases being secondary to an underlying etiology including steroid therapy, severe illness ( meningitis, malaria, and lymphoma), or increased intracranial pressure (7,8). On the other hand, several rare gastrointestinal complications have been reported in children on ECMO, including hemorrhage, emphysematous gastritis and gastric perforation (9). In our patient, duodenal perforation occurred probably in the referring hospital, during the first 2 weeks, when he was battling a severe respiratory infection with H1N1, because the pneumoperitoneum was present upon arrival; had the perforation been diagnosed early enough, the patient’s condition would have probably improved without ECMO. In the adult population, 1 case of fatal perforated peptic ulcer was reported following ECMO removal, and not during the ECMO run (10). Conclusion With the increasing indications for ECMO in critical care, it remains important to spread awareness about the less common complications related to the underlying diseases. References: 1. Berdajs D.Bicaval dual-lumen cannula for venovenous extracorporeal membrane oxygenation: Avalon cannula in childhood disease.Perfusion. 2015 Apr;30(3):182-6. 2. Vaquer S, De Haro C, Peruga P, Oliva JC,ArtigasA.Systematic review and metaanalysis of complications and mortality of veno-venous extracorporeal membrane oxygenation for refractory acute respiratory distress syndrome.Ann Intensive Care2017;7:51-63. 3. Bisdas T, Beutel G, Warnecke G, Hoeper MM, Kuehn C, Haverich A, Teebken OE. Vascular Complications in Patients Undergoing Femoral Cannulation for Extracorporeal Membrane Oxygenation Support, Ann Thorac Surg 2011;92 (2):626–31. 4. S.M Johnson, Itoqa N, Garnett GM, Kilcommons M, Puapong DP, Woo RK. Increased risk of cardiovascular perforation during ECMO with a bicaval, wire-reinforced cannula, Journal of Pediatric Surgery 2014;49(1):46–50. 5. Morrison S, Ngo P, Bill Chiu B. Perforated peptic ulcer in the pediatric population: A case report and literature review. J Pediatr Surg Case Rep 2013;1(12):416-419. 6. Rupprecht et al. Pitfalls in percutaneous ECMO cannulation. Heart, Lung and Vessels 2015;7(4):320-326 7. B. Drumm, J.M. Rhoads, D.A. Stringer, P.M. Sherman, L.E. Ellis, P.R. Durie. Peptic ulcer disease in children: etiology, clinical findings, and clinical course. Pediatrics 1988;82(3Pt 2):410-414. 8. M.C. Hua, M.S. Kong, M.W. Lai, C.C. Luo. Perforated peptic ulcer in children: a 20-year experience. J Pediatr Gastroenterol Nutr 2007;45(1):71-74. 9. Ashfaq A, Chapital AB. Emphysematous gastritis in a patient with coxsackie B3 myocarditis and cardiogenic shock requiring veno-arterial extra-corporeal membrane oxygenation, Int J Surg Case Rep2015;14:121–124. 10. Huang CT, Tsai YJ, Tsai PR, Ko WJ. Extracorporeal membrane oxygenation resuscitation in adult patients with refractory septic shock. J Thorac Cardiovasc Surg 2013;146(5):1041-1046.
