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 fibrinolysis inhibition has demonstrated some benefit in uncontrolled intracranial or intraabdominal hemorrhage, the prothrombotic effect may put the patency of peripheral vascular reconstructions for arterial injuries at risk. While 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 outcomes of arterial reconstruction following vascular injuries to the lower extremity. The PROspective Observational Vascular Injury Treatment (PROOVIT) registry captures in-hospital trauma-specific outcomes related to vascular injuries across 25 U.S. trauma centers. The registry was queried for patients with lower extremity arterial injuries undergoing open reconstruction from 2012-2021. 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 undergoing reconstruction during the study period, 33 (14.2%) received TXA. TXA recipients demonstrated greater physiologic derangement and transfusion requirements (SBP 99 vs. 125 mmHg; lactate 6.2 vs. 4.2 mmol/L; 7.7 vs. 4.2 units pRBC in 24 hours). There were fewer fractures among TXA than non-TXA limbs (24.2% vs. 44.2%, p=.049), but concomitant venous injury was similar (39.4% vs. 36.7%, p=.917). 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 endpoint of arterial reconstruction thrombosis or immediate reoperation (24.2% vs. 11.6%; RR 2.10, 95% CI 1.00-4.40; p=0.048). 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 more proximal injury distribution in TXA recipients and no difference in overall complication rate. 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 towards a procoagulant state. While 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.