Abstract:Objective To review the clinical experience of cardiopulmonary bypass (CPB) in 186 infants with a body weight of less than 10 kg (8.4±0.67 kg ) during the open heart operation.Methods All patients received the congenital heart disease correction operation with cardiopulmonary bypass. The prime volume was 750~1 150 ml, HCT was 23.5±1%, and total plasma protein was 35.5±5 g/L. The average total CPB time and aortic cross clumping time were 62±5.7 min and 35.8±17 min respectively. In 30 infants, who had complex cardiac malformation, moderate hypothermia was used at a rectum temperature of 23~25℃ with a lower perfusion flow of 0.82±0.1 L/m 2(37.6±5.5 ml/kg per min) per min. Results All patients smoothly passed CPB. Twelve cases (12/186) died due to low heart output syndrome after operation. Three of them (3/12) suffered from neurologic complications.Conclusions The cardiopulmonary bypass is an adequate strategy for open heart surgery in infants with a body weight of less than 10 kg.