Is epsilon-aminocaproic acid as effective as aprotinin in reducing bleeding with cardiac surgery? A meta-analysis

Background-Although aprotinin is known to be effective in reducing postoper ative hemorrhage after cardiac surgery, epsilon-aminocaproic acid, an alter native antifibrinolytic, is considerably less expensive. Because the result s of 3 small randomized clinical trials comparing these 2 agents directly w ere inconclusive, we performed a meta-analysis to compare the relative effe ctiveness and adverse-effect profile of these 2 agents against placebo. Methods and Results-Data from 52 randomized clinical trials published betwe en 1985 and 1998 involving the use of epsilon-aminocaproic acid (n=9) or ap rotinin (n=46) in patients undergoing cardiac surgery were abstracted. Our primary outcomes were total blood loss, red blood cell transfusion rates an d amounts, reexploration, stroke, myocardial infarction, and mortality. The meta-analysis revealed substantial reductions in total blood loss with eps ilon-aminocaproic acid and low-dose aprotinin (each with a 35% reduction ve rsus placebo, P<0.001) and high-dose aprotinin (53% reduction, P<0.001). Th ere were identical reductions in total postoperative transfusions with epsi lon-aminocaproic acid (61% reduction versus placebo, P<0.010) and high-dose aprotinin (62% reduction, P<0.001). The proportion of patients transfused was similarly reduced with epsilon-aminocaproic acid (OR, 0.32; 95% CI, 0.1 5 to 0.69) and high-dose aprotinin (OR, 0.28; 0.22 to 0.37). Although both drugs reduced rates of reexploration to similar degrees, this effect was st atistically significant only with high-dose aprotinin (OR, 0.39; 0.24 to 0. 61), epsilon-Aminocaproic acid and aprotinin had no effect on risks of post operative myocardial infarction or overall mortality. Conclusions-Because the 2 antifibrinolytic agents appear to have similar ef ficacies, the considerably less-expensive epsilon-aminocaproic acid may be preferred over aprotinin for reducing hemorrhage with cardiac surgery.