Abstract
To develope a safer and simpler ECMO for pediaic respiratory failure, the new ECMO circuit with an automatically controlled blood pump (Takagi's pump) was studied in eleven small dogs. The ECMO circuit without a reservoir did not require, negative pressure during expansion of a blood chamber, and consisted of a small sized pump and a membrane oxygenator (Merasilox). Its whole priming volume was 120ml. The results were (1) 80 to 90% of the cardiac output was bypassed, and PaO2 increased and PaCo2 decreased significantly during ECMO. (2) the bypass flow was controlled automatically in response to changes in venous return and arterial pressre. (3) blood pressure remained stable for a long period at 50% bypass flow, but fell gradually to circulatory failure at higher bypass flow.