A membrane oxygenator of high gas transfer performance is used as extracorporeal membrane oxygenator for acute respiratory failure (ECMO), too. The membrane oxygenator used in ECMO is required to have a long life and to prevent hemolysis. We completed the multilayer and hollow fiber type membrane oxygenator for ECMO and developed control system of perfusion rate. The material of the membrane of both oxygenators is microporous polypropirene. The multilayer type oxygenator had low pressure drop, high O2 and CO2 transfer rate and prevented hemolysis during 24 hours perfusion with dogs. It was observed with SEM that coagulation and platelets adhesion on the membrane surface was very little. The hollow fiber type oxygenator had high O2 transfer rate, but its CO2 transfer rate was not enough. Its pressure drop was very high for ECMO in long term. The ECMO control system was very useful for long term perfusion.
