Cardiac surgery with cardiopulmonary bypass: does aprotinin affect outcome?

Background. Aprotinin, a non-specific serine protease inhibitor, has been used for two decades to reduce perioperative blood loss and the risk for allogeneic transfusion in cardiac surgery. This study evaluated the effects of aprotinin on outcome (mortality, cardiac events, renal failure, and cerebrovascular events) in such patients undergoing cardiac surgery with cardiopulmonary bypass. Methods. Data were obtained in patients who received a strict blood conservation protocol: no antifibrinolytic therapy when at low risk (n=854) and aprotinin (n=1210) when at high risk for blood transfusion. Relative risk of different pre- and intra-operative variables was calculated for the different outcome variables. Backward stepwise logistic regression analysis was used to identify the independent risk factors associated with the different outcome variables. Statistical significance was accepted at P < 0.01. Results. Postoperative mortality and morbidity were higher in the aprotinin group but this was related to an increased incidence of perioperative risk factors. Mortality was similar to that predicted by the Euroscore. Complex surgery was the only independent variable associated with postoperative cardiac events. Preoperative heart failure, preoperative creatinine > 1.5 mg dl(-1), urgent, and redo surgery were the independent variables associated with postoperative haemodialysis. Age > 70 yr was identified as the only independent variable associated with neurologic dysfunction. Conclusions. In the present study, patients receiving aprotinin as part of a strict blood conservation strategy represent a population at high risk for postoperative complications. For the outcome variables studied, aprotinin administration was not identified as an independent risk factor.