Abstract
This study was done to determine the effect on blood components during extracorporeal circulation between Bio-Pump and Roller-pump. During six hours bypass plasma free hemoglobin increased a little in control group (1.88mg/dl/h) and Bio-Pump group (1.85mg/dl/h). It increased significantly in Roller-Pump group (12.60mg/dl/h). Lactate dehydrogenase value showed same change of free hemoglobin.