Effects of aprotinin on prostaglandin metabolism and platelet function in open heart surgery.

The effects of the protease inhibitor, aprotinin, on plasma prostaglandin levels and platelet function during and after cardiopulmonary bypass (CPB) were studied in a group of 23 patients which consisted of 11 untreated patients (control group) and 12 aprotinin-treated patients (aprotinin group). Thromboxane B2 (TXB2, a stable metabolite of thromboxane A2) and beta-thromboglobulin levels in the control group increased significantly during CPB compared with preoperative values. These increases were significantly suppressed in the aprotinin group. 6-Keto-PGF1 alpha (stable metabolite of prostacyclin) increased significantly during CPB in both groups, and there was no significant difference between the two groups. In the aprotinin group, the TXB2/6-Keto-PGF1 alpha ratio decreased significantly during CPB compared with the preoperative value, whereas no significant decrease was observed in the control group. Platelet counts decreased significantly during and after CPB in both groups. Platelet aggregability decreased significantly during CPB in the control group, whereas no significant decrease was found in the aprotinin group. In conclusion, aprotinin treatment improved prostaglandin metabolism and preserved platelet function during open heart surgery.