QS122 - Time to Return of Bowel Function Following Ileostomy Reversal

Purpose/Background: Ileostomies are often created to divert intestinal contents to protect the gastrointestinal tract distal to the ostomy. Time to reversal remains variable, but is typically performed 2 months after ileostomy creation to avoid operating in a hostile abdomen. Reversals can be performed using a midline incision, laparoscopically, or by local takedown. A key marker of reversal success is having return of bowel function (ROBF) (e.g. flatus or bowel movement (BM)). Currently, limited data exists regarding the time to ROBF as it relates to ileostomy reversal; thus, the purpose of this study is to evaluate the relationship between the time to ileostomy reversal and time to ROBF.

Methods/Interventions: This is a retrospective cohort study of patients undergoing ileostomy reversal at a single university hospital system. Subjects were grouped into < 2 months ( < 2mo), 2-6 months (2-6mo), 6-12 months (6-12mo), and ≥12 months (≥12mo) from the index operation to the ileostomy reversal. The primary outcome was time to ROBF defined as passing flatus or having a BM. Univariate and bivariate analyses were performed. A multivariable linear regression evaluated the relationship between time to ROBF and each of the covariates.

Results/Outcomes: 145 subjects underwent ileostomy reversal between 2017-2021. The duration between index surgery and ileostomy reversal was < 2mo for 14 subjects, 2-6mo for 59 subjects, 6-12mo for 47 subjects, and ≥12mo for 25 subjects. The average number of days until ROBF for < 2mo was 2.7±1.6, 2.3±1.4 for 2-6mo, 3.7±3.6 for 6-12mo, and 2.8±1.8 for ≥12mo (p < 0.05). The rates of adverse events were 26%, 20%, 34%, and 32% for < 2mo, 2-6mo, 6-12mo, ≥12mo, respectively (p = 0.29). Demographic data did not differ between groups. More than 30% of subjects whose ileostomy was reversed after 6 months had end ileostomies, whereas the more than 80% of subjects whose ileostomy was reversed in less than 6 months had diverting loop ileostomies. On the multivariable linear regression analysis, having a post-operative adverse event (beta 1.41 (95%CI 0.4-2.4) p< 0.05) and an end ileostomy (beta 1.32 (0.1-2.5), p< 0.05) were significantly associated with delayed ROBF.

Conclusion/Discussion: On multivariable linear regression, a delayed ROBF had statistically significant associations with ileostomy type and adverse events. Importantly, the average time to ROBF was earlier for subjects whose ileostomy was reversed 2-6mo compared to ≤2mo, 6-12mo, and ≥12mo which suggests that optimal timing of ileostomy reversal with the shortest time to ROBF should be 2-6 months from the index operation.