Effects of aprotinin on the inflammatory response induced by cardiopulmonary bypass

Objective: To observe the effects of high dose aprotinin and low dose aprotinin on the inflammatory response induced by cardiopulmonary bypass (CPB). Methods: Thirty two patients who underwent heart valve replacement were randomized in double blind fashion into three groups: control group (n=6), low dose group (n=13) and high dose group (n=13). Blood samples were taken from radial artery at three times intervals: before CPB, at the end of CPB and 2 hours after termination of CPB. Neutrophil CD 11b integrin expression, plasma level of tumor necrosis factor α (TNF α) and interleukin 6 (IL 6) were measured. Results: The high dose group demonstrated no significant change in neutrophil CD 11b expression and in plasma level of TNF α, but a significant decrease in plasma level of IL 6. However, the low dose group only demonstrated a lower CD 11b expression and a lower TNF α level at 2?h after CPB termination. Conclusion: Aprotinin has a dose reponse effect. High dose aprotinin is more effective in the reduction of inflammatory response induced by cardiopulmonary bypass.