Tranexamic acid is effective in decreasing postoperative bleeding and transfusions in primary coronary artery bypass operations: a double-blind, randomized, placebo-controlled trial

Abstract

We evaluated the effects of tranexamic acid (TA) administered before and after cardiopulmonary bypass (CPB) in a prospective, randomized, placebo-controlled, double-blind study of adult patients undergoing primary coronary artery bypass grafting surgery. Patients received placebo (n = 30) or TA 15 mg/kg before CPB, followed by a TA infusion of 1 mg x kg(-1) x h(-1) for 5 h (n = 30) or TA 15 mg/kg after CPB, followed by a TA infusion of 1 mg x kg(-1) x h(-1) for 5 h (n = 30). Demographic, medical, surgical, laboratory, mediastinal chest tube drainage (MCTD), hemoglobin loss, transfusion, and outcome data were collected. Allogenic blood product administration was tightly controlled. The demographic, medical, and surgical characteristics were similar in all three groups. The median postoperative MCTD and hemoglobin loss in the pre-CPB TA group (710 mL, 8.6 g) was significantly less (P < 0.001) compared with the control (1202 mL, 44.2 g) and post-CPB TA groups (1020 mL, 23.4 g). The percentage of patients who received no allogenic blood products was 27% for the pre-CPB TA group and 33% for the post-CPB TA group (not significant). These percentages were significantly lower than those in the placebo group (66%, P < 0.001). The median number of allogenic blood products administered to the pre-CPB TA group (0 units) was significantly less compared with the control group (4.5 units). The thromboelastogram and fibrinogen split product levels in the pre-CPB TA group indicated better platelet function and less activation of the fibrinolytic system compared with the other two groups (P < 0.05). There were no intergroup differences in reoperation, myocardial infarction, stroke, infections, or death. These data support the use of pre-CPB TA to decrease patient exposure to postcardiopulmonary bypass allogenic blood products.

Implications: In this randomized, placebo-controlled trial, we investigated the efficacy of tranexamic acid to decrease bleeding and blood transfusions after open-heart operations. Tranexamic acid administered before and during the operation was effective in decreasing both bleeding and transfusions. When tranexamic acid was administered immediately after the operation, it had a minor beneficial effect.