From 1991 to 1994 the Dutch Health Insurance Council financed research on Extracorporeal Membrane Oxygenation (ECMO). This is a technique for providing cardiopulmonary bypass to patients with pulmonary and/or cardiac failure. Most often, these patients are premature neonates. During ECMO, blood is drained from the right atrium, pumped along a membrane where gas exchange takes place, and then redirected to the aorta. To prevent blood clotting, heparin is added. However, with the heparin added, the risk of hemorrhage is considerably increased. Therefore, both the chance of surviving and the chance of severe disability are higher with ECMO than with conventional treatment (i.e., ventilator support).