The Selection of Patients for Ambulatory Endovascular Aneurysm Repair of Elective Asymptomatic Abdominal Aortic Aneurysm

Objectives: To identify candidates undergoing elective endovascular aneurysm repair (EVAR) of asymptomatic infrarenal abdominal aortic aneurysm who are eligible for early (≤6 hours) hospital discharge or to have EVAR performed in free-standing ambulatory surgery centers.

Methods: A retrospective medical record review of all elective EVAR performed at a university medical center over 5 years was undertaken. Potential candidates for early discharge or to have EVAR performed in a free-standing ambulatory surgery setting were defined as those who used routine monitoring services only or had self-limited minor adverse events (AE) that were identified, treated, and resolved within 6 hours of surgery. Risk factors for ineligibility were determined by logistic regression. Sensitivity, specificity, negative and positive predictive values were measured to determine the veracity of the risk factor profile.

Results: There were 272 elective EVARs; the mean patient age was 74 years (range, 52-94 years), and 75% were male. Twenty-five operative major AEs (MAE) occurred in 21 patients (7.7%): bleeding (5.9%), thrombosis (1.8%), and arterial injury (1.8%). Percutaneous EVAR (PEVAR) attempted in 260 patients (96%) was successful in 238 (88%). Failed PEVAR was associated with operative MAE (P < .001). Combined operative/postoperative MAE occurred in 43 patients (15.8%); 17 (6%) required intensive care admission; 88% directly from the operating room/postanesthesia care unit. Only two MAE (0.7%) occurred beyond 6 hours; (congestive heart failure at 24 hours, thrombosis/reoperation at 15 hours). Other AE included nausea (17%), blood pressure alteration (15%), and urinary retention (13%). Need for nonroutine services or treatment of other AE occurred in 131 (48%) patients with 79 (29%) developing or requiring treatment ≥6 hours postoperatively. However, 22 (8%) were treated/resolved in <6 hours; 30 (11%) patients required monitoring only and 36% had no complications, so, overall eligibility for same-day discharge/free-standing ambulatory surgery center was 55%. Failed PEVAR (odds ratio [OR], 2.37; 95% confidence interval [CI], 1.25-4.49; P = .008), PEVAR performed outside of instructions for use (IFU) criteria (OR, 2.84; 95% CI, 1.07-7.56; P = .037), Endologix AFX graft (OR, 1.66; 95% CI, 1.19-2.33; P = .003) were independent predictors of MAE or AE occurring/requiring treatment >6 hours postoperatively; EVAR, which did not require an additional aortic cuff, was associated with a lower incidence (OR, 0.17; 95% CI, 0.04-0.65; P = .01). Neither aortic nor limb IFU were independent predictors. Profiles using PEVAR IFU, PEVAR failure, and graft type demonstrated only moderate sensitivity (63%), specificity (71%), positive predictive value (70%), and negative predictive value (63%).

Conclusions: More than one-half of all patients who undergo EVAR are ready for discharge within 6 hours postoperatively. Failed PEVAR, aortic cuffs, and Endologix AFX graft were independent predictors of MAE or AE occurring/requiring treatment for ≥6 hours. However, sensitivity parameters of this profile were insufficient to advocate EVAR in free-standing ambulatory surgical units at this time, but hospital-based ambulatory admission with same-day discharge would be a viable option because of easy inpatient transition for those requiring continued care.

Keywords: Endovascular aneurysm repair (EVAR); Risk factor profiling; Same-day discharge (SDD).