(482) Management of Hemostasis on ECMO in Postoperative Pediatric Liver Transplant Patients

Introduction: Expanded use of extracorporeal membrane oxygenation (ECMO) necessitates modified management strategies for unique populations, such as pediatric orthotopic liver transplant (OLT) recipients. A study noted 63% mortality in pediatric OLT patients receiving ECMO, with non-survivors having more thrombotic and hemorrhagic complications. We describe coagulation management in 3 pediatric OLT patients supported with venovenous ECMO.

Description: Patient A was a 10 mo with biliary atresia cannulated secondary to ARDS 4 days after OLT. Fibrinogen target was 150 mg/dL and platelet (plt) target 50,000/uL. Bivalirudin was used for anticoagulation with initial diluted thrombin time (dTT) 0.4-0.8 ug/mL and PTT Hepzyme 50-70 sec. He had a small cerebellar hemorrhage on ECMO day 5 that was successfully managed with increasing plt goal to 80,000/uL and decreasing dTT to 0.1-0.3 ug/dL. He was decannulated on ECMO day 8. Patient B was a 17 yo with autoimmune hepatitis and hepatopulmonary syndrome (HPS) cannulated 2 months after OLT due to sepsis and ARDS. Plt target was 100,000/uL, which was decreased to 50,000/uL after stabilizing on ECMO. Fibrinogen goal was 200 mg/dL, initial dTT target 0.4-0.8 ug/dL, and PTT Hepzyme 50-70 sec. He came off ECMO on day 32. Patient C was an 11 yo with hereditary hemorrhagic telangiectasia requiring OLT followed by ECMO cannulation 1 month later due to persistent HPS. Plt goal was 100,000/uL, fibrinogen 200 mg/dL, initial dTT target 0.5-1.0 ug/mL, and PTT Hepzyme 50-70 sec. She was decannulated on ECMO day 24 after lung transplant. All patients had goal INR < 2.5 and maintained normal liver function throughout their ECMO course. There were no significant thrombotic or neurologic complications of ECMO.

Discussion: Managing hemostasis in pediatric OLT recipients on ECMO requires a strategic approach. Thrombocytopenia is the most common coagulation abnormality in pediatric OLT recipients, and lower transfusion thresholds are often adopted to mitigate risk of hepatic artery or portal vein thrombosis. Targeting lower anticoagulation levels on ECMO can effectively support these patients while minimizing the need for blood product transfusions. Utilizing a combination of dTT and PTT Hepzyme for bivalirudin monitoring enables precise and safe anticoagulation management post-OLT.