Introduction
Hemolysis is a frequent complication of different extracorporeal circulation and membrane oxygenation (ECMO) support systems. Usually it is assessed by measuring the levels of haptoglobin or the concentrations of free hemoglobin in the plasma, but automated biochemical laboratory analyzers now detect the hemolysis index (HI) of all blood samples as a measure of sample quality. We studied whether this simple index could detect populations at high risk of active hemolysis and whether it is correlated with outcome.