Hemostatic efficacy of dipyridamole, tranexamic acid, and aprotinin in coronary bypass grafting

Sixty patients (four groups of 15 patients) were entered in a randomized, controlled study to compare the efficacy of prophylactic treatment with dipyridamole, tranexamic acid, and aprotinin to reduce bleeding after elective coronary artery bypass grafting. Only patients with a preoperative platelet count of less than 246 × 109/L were selected because a previous study showed that these individuals are at risk for increased postoperative bleeding. Compared to control subjects, postoperative blood loss 6 hours after operation was significantly reduced by tranexamic acid (674 ± 411 versus 352 ± 150 mL; p < 0.05) and by aprotinin (270 ± 174 mL; p < 0.01). Dipyridamole did not reduce postoperative blood loss and was associated with complications in 3 patients. We conclude that hemostasis after cardiac operations can be improved with tranexamic acid and aprotinin. Dipyridamole appeared to be ineffective.