Safety and efficacy of tranexamic acid in major non-cardiac vascular surgery: a systematic review and meta-analysis

Abstract

Background: Tranexamic acid (TXA) is a synthetic lysine analogue that inhibits fibrinolysis. The effectiveness of TXA in obstetrics, trauma and orthopaedic and cardiac surgery is well established. However, concerns regarding its prothrombotic potential remain, which is an important consideration for vascular surgery. We aimed to evaluate the safety and efficacy of TXA in adults undergoing major non-cardiac vascular surgery. Methods: A pre-specified protocol (PROSPERO CRD42023427282) was followed. Relevant databases (PubMed, MEDLINE, EMBASE) were searched for randomised controlled trials (RCTs). Data extraction and risk of bias assessments were performed in duplicate. A random effects model was used to synthesise data from RCTs. Measures of effect were reported as relative risk (RR) with 95% confidence intervals (CIs). The primary safety outcome was a composite of arterial and venous thromboembolic events (composite of myocardial infarction, non-haemorrhagic stroke, peripheral arterial thrombosis and symptomatic proximal venous thromboembolism). Certainty of evidence was assessed using the GRADE approach. Results: After screening 1989 records, three RCTs were included, cumulatively enrolling 1,560 participants. In all trials, patients received either TXA (intravenously or orally) compared with placebo. There was no evidence of the effect of intravenous TXA on thromboembolic events (RR 1.10, 95% CI 0.89 to 1.36, two RCTs, 1460 participants, low certainty of evidence) or on critical bleeding (composite of life-threatening, critical and major organ bleed) (RR 0.85, 95% CI 0.65 to 1.11, two RCTs, 1460 participants, low certainty of evidence). TXA may reduce postoperative blood loss, especially at 0–4 hours (Cliff’s delta −0.41, 95% CI −0.19 to −0.59) and 0–24 hours (Cliff’s delta −0.37, 95% CI −0.14 to −0.55) after surgery. There was no evidence of an effect of TXA on reducing perioperative red blood cell (RBC) transfusion requirements (RR 0.66, 95% CI 0.11 to 3.95, one RCT, 100 participants). One RCT assessed oral TXA and found no evidence of an effect on type II endoleak post endovascular aneurysm repair. No thrombotic complications were reported in this RCT during the study period. Conclusions: We found no evidence of an effect of TXA on thromboembolic complications. While TXA appears to reduce early postoperative bleeding, the clinical relevance of this is uncertain. Due to limitations of study design and the variety of vascular procedures, the role of TXA in vascular surgery is still unclear. Ongoing trials may reduce this uncertainty. Registration: Prospectively registered on PROSPERO (CRD42023427282)