A Sensitive Matter: Performance of Contemporary Outcomes Measures in Detecting Complications in Complex Endovascular Aortic Repair

Abstract

Agency for Healthcare Research and Quality Patient Safety Indicators are quality improvement indicators used to determine hospital performance and, increasingly, to rank surgical programs. The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) and the Society for Vascular Surgery Vascular Quality Initiative (SVS-VQI) databases are also frequently used to compare outcomes, but definitions of complications vary between the systems, and the optimal system for tracking complications in complex endovascular repair remains unclear. Herein we assess the three outcomes tracking systems and their ability to capture complications in fenestrated endovascular (FEVAR) and open aortic aneurysm (OAR) repair at a large complex aortic program. Demographic and operative data for patients undergoing repair of juxta- or pararenal aortic aneurysms between 2004 and 2018 via both open and fenestrated endovascular (FEVAR) approaches at the Johns Hopkins Medical Institutions were compiled in a prospectively maintained retrospective database. Postoperative complications were defined according to the SVS-VQI, ACS-NSQIP and data dictionaries and were compared between surgical approaches as well as eras before and after the introduction of FEVAR. Complication rates between the classification systems were compared using proportion testing and strength of correlation between the systems was evaluated with Spearman’s rank test. Statistical analysis was performed with Stata version 15.1 (StataCorp, Cary, NC). Introduction of fenestrated technology was associated with a decrease in the overall number of complications (37.2% to 20.6%; P = .036). By classification systems, VQI identified the most complications (39.9% of the entire cohort and 25% of FEVAR cases), followed by NSQIP (29.0% and 33.3%, respectively) and PSI (4.1% and 5%, respectively). The two clinically focused databases were found to correlate well with a surgeon-designed classification system as well as each other (Spearman ρ ≥ 0.735) but not with PSI (ρ < 0.23). Proportion testing demonstrated the rate of complications identified by PSI to be significantly less than either VQI or NSQIP (P < .001). Specifically, PSI did not effectively identify renal complications (1.4% vs 9% by NSQIP and 27.3% by VQI definitions; P < .001). The introduction of FEVAR is associated with an overall reduction in complications in this study, mostly owing to a reduction in respiratory complications. The clinically relevant VQI and NSQIP databases show good concordance in capturing complications; however, PSI did not correlate with either and captured significantly fewer complications. This highlights the value of high scrutiny classification systems to track endovascular complications and suggests that PSI are insufficient to rank complex aortic programs with high levels of FEVAR use.