The role of the centrifugal pump in hemolysis during neonatal extracorporeal support.

While the use of the centrifugal vortex ECMO pump as an alternative to a roller-occlusion pump offers distinct advantages, unacceptable hemolysis may occur during its use in newborn infants. The authors studied 87 consecutive neonatal patients with respiratory failure supported with venoarterial ECMO using a centrifugal vortex pump. Baseline mean plasma free hemoglobin level for all patients during the first 48 hours of bypass was 31.3 +/- 3.1 md/dl. In 51 patients, an abrupt rise in the plasma free hemoglobin occurred. In 48 of 51 patients, the pump head alone was changed at 91.9 +/- 6.6 hours after initiation of bypass. Mean plasma free hemoglobin decreased to baseline values following pump head change. The authors could not determine any factors that distinguish the infants who developed hemolysis from those who did not. Changing only the pump head provides a simple approach to hemolysis during use of the centrifugal vortex pump on newborn infants.