BACKGROUND: While general anesthesia (GA) has been the common choice of anesthesia for patients undergoing endovascular aneurysm repair (EVAR), local anesthesia (LA) has been proposed as an effective alternative for eligible patients. However, the choice of anesthesia in emergency EVAR situations remains less explored. Therefore, this study aimed to perform a retrospective analysis to compare the 30-day outcomes of patients who underwent emergency infrarenal EVAR receiving either LA or GA. METHODS: Patients who underwent emergency infrarenal EVAR were identified in the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) targeted database from 2012 to 2022. Exclusion criteria included age less than 18 years, acute intraoperative conversion to open surgery, and intraoperative anesthesia conversion. The 1:1 propensity-score matching and multivariable logistic regression were separately used to balance preoperative factors between patients who received LA and GA. Thirty-day postoperative outcomes were examined. RESULTS: There were 258 (14.58%) and 1512 (85.42%) patients who underwent emergency EVAR under LA and GA, respectively. After multivariable analysis, patients who were under LA had lower mortality (11.24% vs 13.96%, aOR=0.61, 95% confidence interval [CI]=0.395-0.944, p=0.03), pulmonary complications (10.85% vs 17.59%, aOR=0.495, 95% CI=0.322-0.76, p<
0.01), renal complications (5.04% vs 7.47%, aOR=0.545, 95% CI=0.303-0.983, p=0.04), wound complications (0.39% vs 3.64%, aOR=0.089, 95% CI=0.012-0.649, p=0.02), and 30-day readmission (6.59% vs 11.24%, aOR=0.564, 95% CI=0.334-0.953, p=0.03). Moreover, patients under LA had shorter operative time (p<
0.01) and shorter length of stay (p=0.02). CONCLUSION: The LA is associated with better 30-day outcomes in emergency infrarenal EVAR. Therefore, in emergency EVAR, it may be advisable to consider LA over GA for eligible patients. Prospective studies in the future can be warranted to further support this anesthesia practice. CLINICAL IMPACT: The choice of anesthesia in emergency endovascular aneurysm repair (EVAR) remains unexplored. This study performed a retrospective analysis to compare the 30-day outcomes of patients who underwent emergency infrarenal EVAR receiving local anesthesia (LA) or general anesthesia (GA). After propensity-score matching/multivariable analysis to balance preoperative differences, patients under LA were found to have lower 30-day mortality, pulmonary, renal, and wound complications, 30-day readmission, shorter operative time, and shorter hospital stay. In emergency EVAR, it may be advisable to consider LA over GA for eligible patients. Prospective studies in the future can be warranted to further support this anesthesia practice.