Abstract
This study concerns the relationships between the changes of pH and perfusion pressures. The experiments were performed with (Group I) and without (Group II) oxygenation. Group I, which had a total priming volume of 2000ml including 80ml of 7% NaHCO3. Perfusion pressure rose rapidly when pH values exceeded 7.90 and severe deformity and blood mass formation (echinocyte and discocyte) were observed through the scanning microscope. Group II, which had a total priming volume of 2000ml was classified into 12 subgroups according to volumes of NaHCO3 and priming blood. There were no correlations between the volumes of NaHCO3 and perfusion pressures. The mild formation of echinocyte and discocyte were seen on the surface of the membrane oxygenatoos. It has been suggested that keeping the conditions described below is very important for safety in operations: 7% NaHCO3; within 50ml, Priming blood; within 400ml, No oxygenation, Recirculation time; within 60 minutes, pH; below 7.9
