Abstract No. 112 Differences in Postoperative Outcomes of Elective EVAR Performed Under General Anesthesia versus Monitored Anesthesia Care or Intravenous Sedation

Endovascular aortic aneurysm repair (EVAR) carries lower short-term mortality risk and is often preferred to open repair for abdominal aortic aneurysms in high-risk patients. There is a paucity of existing literature evaluating the optimal anesthetic modality for elective EVAR, the majority of what exists being limited to single-center and low sample size comparisons. The goal of this multi-center retrospective analysis is to assess the impact of primary anesthetic type on short-term outcomes of elective infrarenal EVAR. The 2015 to 2019 American College of Surgeons National Surgical Quality Improvement Program database was queried to identify all patients who underwent EVAR for non-ruptured infrarenal aortic aneurysms with either general anesthesia (GA, n = 11,883) or monitored anesthesia care/IV sedation (MAC/IV, n = 831). Coarsened Exact Matching (CEM) was implemented to control for significantly different demographic and preoperative variables. Differences in peri-operative and 30-day complications between the matched cohorts were analyzed for statistical significance (Man-Whitney U test and Fisher's exact test). CEM generated matched cohorts for GA (n = 9,147) and MAC/IV (n = 757) that were controlled for differences in demographics and pre-operative characteristics. Compared to their MAC/IV counterparts, the CEM-matched GA patients had significantly longer operative times (p < 0.001) and remained hospitalized for longer post-operatively (p = 0.001). In aggregate, the GA cohort demonstrated increased risk of having any tracked complication (RR = 1.32, p = 0.008), any major complication (RR = 1.31, p = 0.043), or any minor complication (RR = 1.48, p=0.008). The GA cohort also demonstrated significantly greater rates of postoperative renal complications (RR = 5.39, p = 0.015) and blood transfusions (RR = 1.43, p = 0.047) compared to the MAC/IV sedation cohort. Controlling for differences in patient characteristics, patients who underwent endovascular repair for non-ruptured infrarenal abdominal aortic aneurysm with GA demonstrated increased overall morbidity compared to patients treated with MAC/IV. While GA may remain preferred for more complex repairs requiring longer operative duration, MAC/IV should be strongly considered as an alternative in the appropriate clinical setting. Future prospective studies are indicated to further analyze the impact of anesthetic technique on outcomes following endovascular procedures such as EVAR.