Tranexamic acid in open aortic aneurysm surgery: a randomised clinical trial.

BACKGROUND:Bleeding and transfusions affect mortality in aortic surgery. Although tranexamic acid significantly reduced bleeding in multiple settings, its role in major vascular surgery was never studied. The aim of this study was to determine if tranexamic acid reduces blood loss in open abdominal aortic aneurysm (AAA) surgery. METHODS:A total of 100 patients undergoing elective open AAA repair were randomised to receive tranexamic acid (a loading dose of 500 mg and a continuous infusion of 250 mg h-1) or placebo. The primary outcome was intraoperative blood loss, and the secondary outcomes were the number of patients receiving red blood cells, occurrence of thromboembolic events, and mortality. Data were analysed using the intention-to-treat principle. RESULTS:Fifty patients were randomised into each group. Median (inter-quartile range) intraoperative blood loss was 400 (300-1050) ml in the tranexamic acid group vs 500 (360-1000) ml in the placebo group (P=0.44). Transfusion rate was seven/50 (14%) in the tranexamic group vs 12/50 (24%) in the placebo group (P=0.20). No thrombosis was recorded. In a post hoc analysis, postoperative blood loss was reduced in the tranexamic group both at 4 h (60 [40-80] ml vs 100 [60-140] ml, P<0.001) and 24 h (180 [120-275] vs 275 [190-395] ml, P=0.003) after surgery. At 1 yr, three patients were dead, all in the placebo group (P=0.24) and all after 28 days. CONCLUSIONS:Tranexamic acid did not reduce intraoperative blood loss or blood transfusions in open AAA repair, although it may reduce postoperative blood loss without increasing adverse effects. CLINICAL TRIAL REGISTRATION:NCT02335359.