Value of Routine Flexible Sigmoidoscopy and Potential Predictive Factors for Colonic Ischemia after Open Ruptured Abdominal Aortic Aneurysm Repair

Abstract

Background and Objectives: colonic ischemia (CI) after ruptured abdominal aortic aneurysm (rAAA) repair is associated with increased morbidity and mortality. CI may be detected by using flexible sigmoidoscopy, but routine use of flexible sigmoidoscopy after rAAA is not clearly proven. The objective of this study was to evaluate the efficacy of routine flexible sigmoidoscopy in detecting CI after rAAA repair, and to identify potential hemodynamic, biochemical, and clinical variables that can predict the development of CI in the patients who underwent rAAA surgery. Materials and Methods: we retrospectively included all rAAA cases treated in Viborg hospital from 1 April 2014 until 31 August 2017, recorded the findings on flexible sigmoidoscopy, and the incidence of CI. We collected specific hemodynamic, biochemical, and clinical variables, measured pre- and perioperatively, and the first three postoperative days. The association between CI and possible predictors was analyzed in a logistic regression model. Results: a total of 80 patients underwent open rAAA repair during the study period. Flexible sigmoidoscopy was performed in 58 of 80 patients (73.5%) who survived at least 24 h after open rAAA surgery. Perioperative variables lowest arterial pH (p = 0.02) and types of operations—aortobifemoral bypass vs. straight graft (p = 0.04) showed statistically significant differences between CI groups. The analysis of the postoperative variables showed statistically significant difference in highest lactate on postoperative day 1 (p = 0.01), and lowest hemoglobin on postoperative day 2 (p = 0.04) comparing CI groups. Logistic regression model revealed that postoperative hemoglobin and lactate turned out to be independent risk factors for the development of CI (respectively OR = 0.44 (95% CI = 0.29–0.67) and OR = 1.91 (95% CI = 1.2–3.05)). Conclusions: flexible sigmoidoscopy can identify patients being at higher risk of mortality after open rAAA repair. The postoperative lactate and hemoglobin were found to be independent risk factors for the development of CI after open rAAA repair. Further larger studies are warranted to demonstrate these findings.

Detection of Ischemic Colitis on Routine Lower Endoscopy and Its Implications After Repair of Ruptured Abdominal Aortic Aneurysm

“…Of the 12 studies, four involved rAAA and the reported rates of IC were 22-39%. Most recently in 2020, Urbonavicius published IC rates detected on routine endoscopy after OSR which was 33% (n = 58) 30 . Our institution’s prior study from 2007 is currently the only other to report the rate of IC detected on routine lower endoscopy after EVAR for rAAA which was 23%, 9 and our current study confirms a similar rate of 20% for EVAR.…”

“…Of the 12 studies, four involved rAAA and the reported rates of IC were 22-39%. Most recently in 2020, Urbonavicius published IC rates detected on routine endoscopy after OSR which was 33% (n = 58) 30 .…”

“…2,28,29 With routine endoscopic surveillance, our surgical intervention rate of 7.9% was not increased when compared to other similar studies (3.9 to 14.5%). 9,10,26,27,30 Surgical intervention after rAAA repair portends a poor outcome given that 5 of 9 patients after abdominal exploration died. Data was not collected to determine if and how routine endoscopy influenced the inclination for surgical intervention.…”