Tranexamic acid (Cyklokapron) is not necessary to reduce blood loss after coronary artery bypass operations

The contribution of fibrinolysis to postoperative bleeding after cardiopulmonary bypass led to routine use of tranexamic acid, a potent antifibrinolytic drug, for a period of time. Two hundred patients undergoing elective coronary artery bypass operations were studied, one group of 100 patients given tranexamic acid (40 mg/kg) (group I) after bypass and one subsequent group of 100 patients (group II) serving as a control group. All patients were treated by the same team, and the groups were comparable in all major clinical parameters. The mean mediastinal drainage in group I was 565 +/- 239 ml versus 656 +/- 257 ml in group II. Univariate and multivariate analysis revealed statistical significance (p = 0.02) when corrected for body surface area. However, applying a consistent blood conservation protocol, including removal of autologous blood before bypass for retransfusion after bypass, returning of all oxygenator and tubing contents to the patients, and autotransfusion of the mediastinal shed blood up to 18 hours postoperatively, resulted in nearly identical hemoglobin concentration at discharge (119 +/- 14 gm/L in group I and 121 +/- 14 gm/L in group II). The prevalence of postoperative myocardial infarction included five patients in group I compared with one patient in group II. Although not statistically significant (p = 0.2), the difference is of concern. Tranexamic acid has a beneficial effect on reducing postoperative bleeding after coronary artery bypass operations. The routine use of the drug is not recommended, however, because its effect is a weak one, and it may be of potential hazard by precipitating thrombosis and eventual myocardial infarction.