Conservative oxygen therapy in extracorporeal membrane oxygenation for post-transplant refractory hypoxemia in a pediatric liver transplant recipient with very severe hepatopulmonary syndrome: A case report

Rationale: Extracorporeal membrane oxygenation (ECMO) is an effective treatment for post-transplant refractory hypoxemia in pediatric liver transplant recipients with very severe hepatopulmonary syndrome (HPS), which has high mortality. Conservative oxygen therapy (COT) during ECMO for these patients may be helpful to avoid excessive oxygen toxicity while ensuring tissue oxygen supply. However, there is no prior report on this specific strategy. This study is the first successful report on ECMO with COT strategy in the treatment of the above-mentioned patients. Patient concerns: We report a 5-year-old patient who was admitted to the hospital due to recurrent gastrointestinal bleeding accompanied by long-term hypoxemia. The patient had a medical history of biliary atresia and had previously undergone the Kasai procedure. Diagnoses: Based on the laboratory results such as liver CT and liver function, combined with the history of Kasai operation for biliary atresia and repeated gastrointestinal bleeding, the child was diagnosed with liver failure. Upon evaluation with contrast-enhanced transthoracic echocardiography and abnormal arterial oxygenation, a diagnosis of HPS was established. Based on the preoperative arterial oxygen pressure measured at 45 mm Hg on room air, she was classified with very severe HPS. Interventions: After liver transplantation (LT), her liver function was gradually recovering. However, she required veno-arterial ECMO for severe respiratory and circulatory failure. During ECMO, COT strategy was applied. Outcomes: By the 10th day post-LT, her liver function had returned to normal completely. However, the refractory hypoxemia related to intrapulmonary arteriovenous shunting caused by HPS was not corrected immediately. Until the 38th day post-LT, with the support of the ECMO with COT strategy, HPS was completely cured. Lessons: This case demonstrates the effectiveness of combining LT and ECMO for very severe HPS, emphasizing the importance of COT combined with ECMO management.