Tranexamic acid reduces bleeding risk during coronary artery surgery

Patients who received tranexamic acid while undergoing coronary artery surgery had a lower risk of bleeding but a higher risk of postoperative seizures compared with a placebo group, according to a randomized trial.

The tranexamic acid and placebo groups had similar rates of death and thrombotic complications within 30 days following surgery. Tranexamic acid is a lysine analogue and antifibrinolytic agent.

Lead researcher Paul S. Myles, MPH, of Alfred Hospital and Monash University in Melbourne, Australia, and colleagues published their results online in the New England Journal of Medicine on Oct. 23. The findings were also presented at the American Society of Anesthesiologists annual meeting in Chicago.

This study, which had a 2-by-2 factorial design, included 4,662 adults who were at an increased risk for major complications related to age or coexisting conditions and were undergoing on-pump or off-pump coronary artery surgery. The researchers enrolled patients at 31 sites in seven countries.

Patients received intravenous tranexamic acid or 0.9 percent saline (placebo) more than 30 minutes after anesthesia. For the tranexamic acid group, the researchers tried to maintain an effective plasma concentration for approximately 6 to 8 hours. In the tranexamic acid group, 758 patients received the drug at a dose of 100 mg per kilogram of body weight, while 1,553 patients received the drug at a dose of 50 mg per kilogram of body weight.

Within the first 30 days after surgery, 16.7 percent of patients in the tranexamic group and 18.1 percent of patients in the placebo group died or had thrombotic complications. Meanwhile, 11.6 percent and 12.9 percent of patients, respectively, had an MI within 30 days. The rates of death, stroke, pulmonary embolism, renal failure and bowel infarction were also similar between the groups.

Meanwhile, the tranexamic group had significantly lower rates of blood loss during surgery, units of red cells and other transfused blood products and blood transfusions. Postoperative seizures occurred in 0.7 percent of patients in the tranexamic group and 0.1 percent of patients in the placebo group.

The researchers mentioned that the tranexamic group received 46 percent fewer units of blood products, which they estimated would save approximately 57 units of blood products for every 100 patients treated.

They added that the study had a few limitations, including that it did not include many patients at the highest risk for bleeding or thrombosis and included only a small percentage of patients undergoing off-pump surgery. In addition, some attending anesthesiologists were aware of the treatment-group assignment.