INTRAOPERATIVE ANTIFIBRINOLYSIS AND BLOOD-SAVING TECHNIQUES IN CARDIAC-SURGERY - PROSPECTIVE TRIAL OF 3 ANTIFIBRINOLYTIC DRUGS

Sixty consecutive patients undergoing elective open-heart surgery were prospectively enrolled in a study to compare the efficacy of 3 differ ent antifibrinolytic drugs to reduce postoperative bleeding and to red uce homologous blood requirements in combination with blood-saving tec hniques and restrictive indications for blood transfusion. The patient s were randomized to 1 of 4 intraoperative treatment regimens: 1) cont rol (no antifibrinolytic therapy); 21 epsilon-aminocaproic acid (10 g IV at induction of anesthesia, followed by infusion of 2 g/h for 5 hou rs); 3) tranexamic acid (10 mg/kg IV within 30 minutes after induction of anesthesia, followed by infusion of 1 mg/kg per hour for 10 hours) , or 4) high-dose aprotinin (2 million KIU IV at induction of anesthes ia and 2 million KIU added to the extracorporeal circuit, followed by infusion of 500 thousand KIU/h during surgery). Hemoconcentration and reinfusion of blood drained from the operative field and the extracorp oreal circuit after operation were used in all patients. Indications f or blood transfusion were hypotension, tachycardia, or both, with hemo globin values < 8.5 g/dL; or severe anemia with hemoglobin values < 7 g/dL. Compared with the blood loss in the control group, patients rece iving aprotinin and epsilon-aminocaproic acid showed significantly les s postoperative blood loss at 7 hour (control, 128 +/- 94 mL, aprotini n, 54 +/- 47 mL, p = 0.01; and epsilon-aminocaproic acid, 69 +/- 35 mL , p = 0.03), this trend continued at 24 hours after operation (control , 724 +/- 280 mL; aprotinin, 344 +/- 106 mL, p < 0.0007, and epsilon-a minocaproic acid, 509 +/- 148 mL, p = 0.01). Aprotinin was significant ly more efficient than epsilon-aminocaproic acid (p = 0.002). Tranexam ic acid did not have a statistically significant effect on blood loss. Homologous blood requirements were not significantly different among the groups; postoperative hematologic values and coagulation limes wer e also comparable. Despite the efficacy of aprotinin and E-aminocaproi c acid shown in the present study, the blood requirements were not sig nificantly different from those that are found when transfusions are r estricted autotransfusions are used, and blood from the operative fiel d and extracorporeal circuit is concentrated and reinfused. Therefore, intraoperative antifibrinolysis may not be indicated in routine cardi ac surgery when other blood-saving techniques are adopted.