Comprehensive assessment of factors associated with in-hospital mortality after elective abdominal aortic aneurysm repair

Abstract

Importance: Patient- and hospital-level factors affecting outcomes after open and endovascular abdominal aortic aneurysm (AAA) repair are each well described separately, but not together. Objective: To describe the association of patient- and hospital-level factors with in-hospital mortality after elective AAA repair. Design, Setting, and Participants: Retrospective review of the Nationwide Inpatient Sample database (January 2007-December 2011). The review included all patients undergoing elective open AAA repair (OAR) or endovascular AAA repair (EVAR) and was conducted between December 2014 and January 2015. Main Outcomes and Measures: Factors associated with in-hospital mortalitywere analyzed for OAR and EVAR using multivariable analyses, adjusting for previously defined patient- and hospital-level risk factors. Results: Of the 166 443 surgeries (131 908 EVARs and 34 535 OARs) that were performed at 1207 hospitals, 133 407 patients (80.2%) were men, 123 522 patients (89.6%) were white, and the mean (SD) age was 73 (0.04) years. Overall in-hospital mortality was 0.7%for EVAR and 3.8% for OAR. Mortality after EVAR was significantly higher among hospitals with high general surgery mortality (mortality quartile ≥ 50%; odds ratio [OR], 1.37; 95% CI, 1.01-1.86; P = .04) and there was no difference in mortality among hospitals meeting the Leapfrog criteria for AAA repair (OR, 0.64; 95% CI, 0.38-1.09; P = .09). Mortality after OAR was significantly lower among hospitals performing at least 25% of AAA repairs using open techniques (OR, 0.68; 95% CI, 0.52-0.88; P = .004). Neither hospital bed size nor teaching status was significantly associated with mortality after either EVAR or OAR. Overall, OAR (OR, 6.07; 95%CI, 4.92-7.49) and intrinsic patient risk (Medicare score; OR, 4.81; 95%CI, 3.45-6.72) were most likely associated with in-hospital mortality after AAA repair, although hospitals with poor general surgery performance (OR, 1.31; 95%CI, 1.06-1.63) and those with at least a 25% proportion of open cases (OR, 1.39; 95%CI, 1.10-1.75) were also significantly associated with mortality (all P < .002). Notably, the proportion of institutions performing at least 25% open cases fell from 41% in 2007 to 18% in 2011 (P < .001). Conclusions and Relevance: Patient-level factorswere associated with in-hospital mortality outcomes after elective AAA repair. Hospital case volume and practice patterns were also associated. This demonstrates the importance of adequate institutional experience with OAR techniques, which appear to be critically declining. Based on these data, appropriate patient selection and medical optimization appear to be the most important means by which we can improve outcomes following elective AAA repair, although patient referral to high-volume aortic centers of excellence should be a secondary consideration.