Are right-sided colectomies for neoplastic disease at increased risk of primary postoperative ileus compared to left-sided colectomies? A coarsened exact matched analysis

Introduction The objective of this study was to determine whether right-sided colectomies (RC) were associated with a higher incidence of primary postoperative ileus (pPOI) compared to left-sided colectomies (LC). Methods Patients who underwent elective colectomy for neoplastic disease between 2012 and 2016 were identified using the American College of Surgeons National Surgical Quality Improvement Program database. RC and LC were defined as having an ileocolic or colocolic/colorectal anastomosis, respectively. Coarsened Exact Matching (CEM) was used to balance the two groups (1:1) on important confounders. The association between type of colectomy and pPOI, defined as POI in the absence of intra-abdominal sepsis, was then assessed in a multiple logistic regression analysis of the matched data. Results Of 40,636 patients who underwent a colectomy for neoplastic disease, 15,231 underwent a RC and 25,405 a LC. After CEM, 12,949 matched patients remained in each group, and all important confounders were well balanced. The incidence of pPOI was higher in the RC group (11.5% vs. 8.8%,p < 0.001). On multiple logistic regression, RC was associated with a 35% higher odds of developing pPOI compared to LC (OR 1.35, 95% CI 1.25-1.47). RC was also associated with increased risk for NSQIP-defined major morbidity (OR 1.10, 95% CI 1.01-1.20), 30-day readmission (OR 1.16, 95% CI 1.06-1.27), and increased length of stay (beta = 0.16 days, 95% CI 0.11-0.22). Conclusion pPOI is more common after RC than LC. Future research should aim at better understanding the pathophysiology behind this increased risk and identifying interventions to mitigate pPOI in this population.