Altered liver function in patients undergoing veno-arterial extracorporeal membrane oxygenation (ECMO) therapy

Multiple organ dysfunction can occur in patients undergoing Veno-arterial Extra Corporal Membrane Oxygenation (VA-ECMO); however, liver function has not been well studied in this setting.

In a review of our institutional ECMO database (n=162), we collected aspartate (AST) and alanine (ALT) transaminases, total bilirubin and international normalized ratio (INR) at time of ECMO initiation (baseline) and once daily during therapy in patients who survived for at least 24 hours. Elevated liver enzymes (ELE) were defined if AST and/or ALT were > 200 UI/L, and acute liver failure (ALF) as the presence of an INR ≥ 1.5, new onset encephalopathy and an elevated total bilirubin concentrations.

On a total of 80 patients undergoing VA-ECMO, 69 patients met the inclusion criteria (cardiogenic shock, n=52; refractory cardiac arrest, n=15; cardiac failure following severe ARDS, n=2). Of them, 45 (65%) had early ELE after ECMO initiation (median highest AST and ALT were 528 [251-2606] UI/L and 513 [130-1031] UI/L, respectively). Two thirds of patients with ELE (N = 30) had a progressive reduction in AST and ALT, but the levels were normalized only after 5 [5-6] days. Among patients with ELE, 21/45 (47%) had AST and/or ALT levels above > 1000 UI/L. A total of 14/69 (20%) patients developed ALF. However, mortality rate was not significantly higher in patients with ELE or ALF when compared to others.

A substantial proportion of patients needing VA-ECMO have early ELE, which usually improves over days. The prognostic implications are not evident.