Impact of Previous Open Abdominal Surgery on Open Abdominal Aortic Repair: A Study from the NSQIP Database

Abstract

While endovascular aneurysm repair has become a first-line strategy in many centers, open surgical repair (OSR) of abdominal aortic aneurysms (AAAs) is still the best option for certain patients. A significant number of patients who are offered OSR for AAA have been previously submitted to other open abdominal surgeries (PAS). It is unclear, however, how this may impact their outcomes. The purpose of this study was to determine if there is an association between PAS and outcomes of OSR of AAA. This is a retrospective cohort study based on clinical data from the American College of Surgeons National Surgical Quality Improvement Program database, including all patients undergoing elective OSR for AAA between 2011 and 2017. Excluded were patients with missing data on prior abdominal surgery, supramesenteric clamping, or urgent repairs. Patients with prior abdominal surgery (PAS) and patients without prior abdominal surgeries (nonPAS) were compared. The primary outcome was 30-day postoperative mortality. Secondary outcomes were operating time, ischemic colitis, postoperative complications, and lengths of hospital stay. Of the 2034 patients included, 27% had previous open abdominal surgery and 73% did not. Overall, the median age was 71(interquartile range 65-76), 72% of patients were male, 44% were smokers, and the average body mass index was 27kg/m2. Univariate analysis showed no difference in postoperative 30-day mortality (4.0% PAS vs. 4.1% nonPAS, P=0.91) or overall postoperative complication rates (33% PAS vs. 29% nonPAS, P=0.07). Previous open abdominal surgery was significantly associated with longer operating times (P=0.032) and an almost doubled rate of ischemic colitis (4.7% PAS vs. 2.6% nonPAS, P=0.02). Postoperative intensive care unit and hospitalization were also significantly longer in patients with prior abdominal surgery (P=0.005 and P=0.014, respectively). Finally, there were significantly less patients discharged home, as opposed to institutionalized care (75.7% PAS down from 82.4% nonPAS, P=0.001). Despite these initial univariate analysis results, on multivariate analysis, PAS actually did not prove to be a statistically significant independent risk factor for 30-day mortality, ischemic colitis, or longer operating times. This study suggests that patients who have undergone PAS may have some disadvantages in OSR of AAA. However, these negative trends do not go so far as to statistically significantly identify PAS as an independent risk factor for 30-day mortality, ischemic colitis, or longer operating times. As such, we suggest that a history of previous open abdominal surgery, in and of its own, should not exclude patients from consideration for open aortic abdominal aneurysm repair.