The importance of colloid osmotic pressure during open heart surgery in infants.

Fifty-five infants with transposition of the great arteries and with total anomalous pulmonary venous return underwent intracardiac repair under combined surface/perfusion hypothermia and total circulatory arrest in 1975 to 1983. Although cardiopulmonary bypass (CPB) time is limited when hypothermic circulatory arrest is employed, fluid balance derangement is one of the major postoperative complications. Fluid balance at the end of CPB averaged +299.5 ml (+63.4 ml/kg) when hemodilution with lactated Ringer's was utilized (Group A). Since colloid osmotic pressure (COP) plays an important role in regulating fluid balance, colloid hemodilution prime (whole blood and plasma) was employed in the last 3 years (Group B). COP and total protein concentration during CPB with colloid prime were maintained at around 19 mmHg and 5 g/100 ml, respectively. In Group B, fluid balance at the end of CPB averaged +81.1 ml (+16.3 ml/kg) and was significantly less than in Group A (p less than 0.01). The ICU stay period for survivors in Group B (average 10.9 days) was reduced to half the period in Group A (average 20.6 days) (p less than 0.05). The mortality rate in Group A was 42%, whereas 23% in Group B. It was concluded that well-maintained COP levels during CPB with colloid hemodilution prime reduced fluid accumulation in the body and made patient care easier following open heart surgery in infants.