RETRACTED: INFLUENCE OF APROTININ ON THE THROMBOMODULIN PROTEIN-C SYSTEM IN PEDIATRIC CARDIAC OPERATIONS (Retracted article. See vol. 161, pg. 1562, 2021)

Thirty consecutive children scheduled for pediatric cardiac operation with cardiopulmonary bypass were included in the study. Before the operation, the patients were randomly divided into two groups: with aprotinin (n = 15, 30,000 U/kg after induction of anesthesia, 30,000 U/kg added to the prime of the cardiopulmonary bypass system followed by additional 30,000 U/kg every hour until the end of cardiopulmonary bypass or without aprotinin (n = 15). Thrombomodulin, (free) protein S, protein C, and thrombin/antithrombin complex were measured from arterial blood samples taken after induction of anesthesia (at baseline, before aprotinin) and before, during, and after cardiopulmonary bypass until the first postoperative day. Standard coagulation parameters (antithrombin III, fibrinogen, platelet count, and partial thromboplastin time) were without differences between the groups. Thrombomodulin plasma concentrations were within normal range (<40 mu g/L) and were similar in both groups at baseline. During cardiopulmonary bypass and until 5 hours after cardiopulmonary bypass, however, thrombomodulin plasma levels mere significantly lower in the children treated with aprotinin. No further differences were observed on the first postoperative day. Protein C and protein S plasma levels did not differ between the two groups. Thrombin/antithrombin III-complex plasma concentrations increased significantly during cardiopulmonary bypass, however, without showing differences between children with (225 +/- 49 mu g/L) and without (149 +/- 31 mu g/L) aprotinin treatment. Blood loss and the need for homologous blood and blood products did not differ significantly between the two groups. We concluded that administration of aprotinin resulted in reduced thrombomodulin plasma levels in pediatric patients undergoing cardiac operation without altering protein C/protein S plasma concentration. The exact role of aprotinin in endothelium-derived coagulation should be further studied.