SS14 - Tranexamic acid is associated with thrombosis and reoperation of vascular reconstructions for lower extremity arterial injuries

Objectives: 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.

Methods: The PROspective Observational Vascular Injury Treatment (PROOVIT) registry captures in-hospital trauma-specific outcomes related to vascular injuries across 14 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.

Results: 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; 7.7 vs 4.2 total units of PRBCs). There were fewer fractures among TXA than non-TXA limbs (32% vs 44% p=0.031), but the incidence of concomitant venous injury was similar (39% vs. 37%, p=0.77). Injury distribution was predominately confined to the popliteal and femoral artery with TXA patients more likely to sustain femoral artery injuries (Table 1). Autologous bypass was the most common arterial reconstruction (67%), and the distribution of repair types did not differ between groups. Systemic anticoagulation was used in 67% of TXA and 73% of non-TXA cases (p=0.43). Limb loss was similar (9.5% TXA, 15% non-TXA, p=0.52), however TXA was associated with a twofold increase in arterial reconstruction thrombosis or immediate reoperation (RR 2.10, 95% CI 1.00 – 4.40; p=0.047, Figure 1).

Conclusions: Administration of TXA in patients undergoing open lower extremity reconstruction for arterial injuries was associated with graft thrombosis or immediate reoperation. This increased risk was observed despite more proximal arterial injuries in TXA recipients and in the absence of a difference in overall complication rates, raising concern for a potential adverse effect of TXA on early arterial patency. The risk of arterial thrombosis should be considered in the decision to administer TXA and more judicious use of TXA is warranted in trauma patients who will undergo extremity arterial reconstruction.