Impact of time to repair on outcomes in patients with lower extremity arterial injuries

Background: Six hours has long been considered the threshold of ischemia after peripheral artery injury. However, there is a paucity of evidence regarding the impact of operative delays on morbidity and mortality in patients with lower extremity arterial injuries. Methods: We analyzed the records of 3,441,259 injured patients entered into the National Trauma Data Bank Research Dataset from 2012 to 2015. Patients (≥16 years) with lower extremity arterial injuries were identified by International Classification of Diseases, Ninth Revision injury and procedure codes. Patients with crush injuries, patients with prehospital or emergency department cardiac arrest, those not transferred directly from point of injury, and patients in whom a nonoperative management strategy was attempted were excluded from analysis. Results: We examined the data from 4406 patients with lower extremity arterial injuries; 85% of the patients were male, with a mean age of 35 years. The overall mortality in this cohort was 3.2% (143/4406); the amputation rate was 11.3% (499/4406). Using a multivariate logistic regression model, blunt mechanisms of injury, increased time from injury to operating room arrival, nerve injury, associated lower extremity fractures, increased age, and Injury Severity Score were associated with increased amputation risk. The amputation rate in those undergoing repair within 60 minutes was 6% compared with 11.7% and 13.4% in those undergoing repair after 1 to 3 hours and 3 to 6 hours, respectively. Conclusions: Optimal limb salvage is achieved when revascularization of lower extremity arterial injury occurs within 1 hour of injury. To improve survival and recovery after extremity arterial injury, efforts should be focused on strategies to expedite reperfusion of the injured limb.