Preoperative Biologics Exposure Predisposes Ulcerative Colitis Patients to a Distinct Delayed Postoperative Ileus Syndrome After Colectomy

BACKGROUND Postoperative ileus (POI) remains the most common complication after colectomy for inflammatory bowel disease (IBD). Delayed POI (DPOI) can develop late (>14 days) after colectomy in clinical settings, with unknown etiology. The aim of this study was to address a novel entity of POI after colectomy for ulcerative colitis (UC). MATERIAL AND METHODS The data of 263 UC patients who underwent colectomy from Jan 1, 2013 to May 31, 2021 were collected. DPOI was defined as POI occurring on or after postoperative day (POD) 14 with apparent resolution from obligatory POI. Univariate and multivariate analysis were conducted to identify the risk factors for DPOI. RESULTS The rate of canonical prolonged POI and DPOI were 11.7% (31/263) and 9.9% (26/263), respectively. The pathophysiological process of DPOI demonstrated an ileus-dysbiosis-recovery triad. Two DPOI cases were diagnosed with UC-related severe enteritis and underwent re-laparotomy. Multivariate analysis showed preoperative biologics exposure was an independent risk factor for DPOI (OR 3.100 95% CI 1.261-7.619, P=0.018) and the number of biologics session/course moderately predicted the occurrence of DPOI (AUC=0.639, 95% CI=0.578-0.697, P=0.0129). CONCLUSIONS A distinct pattern of ileus was identified in a tertiary IBD center. Clarification of this syndrome complemented the spectrum of post-IPAA complications and offered experience to treat this condition.