Tranexamic acid is associated with thrombosis and reoperation of vascular reconstructions for lower extremity arterial injuries.

Abstract

Tranexamic acid (TXA) is commonly administered to injured patients presenting with hemorrhagic shock. While TXA's inhibition of fibrinolysis has demonstrated some benefit in uncontrolled intracranial or intra-abdominal hemorrhage, the prothrombotic effect may put the patency of peripheral vascular reconstructions performed for arterial injuries at risk. Although TXA has been associated with venous thromboembolism, its impact on vascular reconstruction following arterial injury has not been elucidated. We aimed to examine the association between TXA and the outcomes of arterial reconstruction following vascular injuries to the lower extremity. The PROspective Observational Vascular Injury Treatment registry captures in-hospital, trauma-specific outcomes related to vascular injuries across 25 US trauma centers. The registry was queried for patients with lower extremity arterial injuries who underwent open reconstruction between 2012 and 2021. Cases were categorized based on documented administration of TXA. The primary outcome measurement was a composite of reconstruction thrombosis and/or immediate reoperation. Among 232 lower extremity injuries that underwent reconstruction during the study period, 33 patients (14.2%) received TXA. TXA recipients demonstrated greater physiologic derangement and transfusion requirements (systolic blood pressure, 99 vs 125 mmHg; lactate, 6.2 vs 4.2 mmol/L; 7.7 vs 4.2 units packed red blood cells in 24 hours). There were fewer fractures among TXA-treated limbs compared with non-TXA-treated limbs (24.2% vs 44.2%; P = .031), but concomitant venous injury was similar (39.4% vs 36.7%; P = .765). Autologous vein interposition or bypass was the most common reconstruction (66.8%), and repair type, anticoagulation use, and limb loss did not differ between groups. TXA was associated with a 2.1-fold increase in the composite end point of arterial reconstruction thrombosis or immediate reoperation (24.2% vs 11.6%; relative risk, 2.10; 95% confidence interval, 1.00-4.40; P = .048). Administration of TXA in patients undergoing open lower-extremity reconstruction for arterial injuries was associated with a twofold increase in the risk of early reconstruction failure, despite a more proximal injury distribution in TXA recipients and no difference in overall complication rates. The standard bolus + 8-hour infusion protocol of TXA may extend antifibrinolytic activity into the operative period when the coagulopathy of trauma has already shifted toward a procoagulant state. Although TXA remains an important resuscitative tool, these findings support further investigation into the risk-benefit profile of current dosing protocols in patients undergoing extremity arterial reconstruction and early collaboration between trauma and vascular surgery teams when vascular injury is suspected.