eP401 - Unplanned Hospital Resource Utilization Between Diverting Loop Ileostomy Formation and Reversal

Purpose/Background: A diverting loop ileostomy (DLI) is commonly constructed for protection of high-risk or low pelvic anastomoses to reduce the morbidity of an anastomotic leak. Unfortunately, DLIs have their own associated morbidity resulting in unplanned hospital resource utilization (UHRU). The morbidity directly attributable to the DLI itself in the entire interval between its creation and reversal is not well studied. Therefore, we aimed to determine the incidence of UHRU events directly related to the DLI in a multi-institutional cohort of patients.Methods/Interventions: Patients undergoing DLI reversal from January 2012 through December 2021 across three sites of a multistate health system were identified within each institution’s American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. The institutional-level electronic medical record was reviewed to collect data points of interest not included in the ACS-NSQIP database and to link the patients back to their original operation. This allowed the capture of all hospital resource utilization between stoma formation and closure, which is beyond the traditionally reported ACS-NSQIP 30-day window. The primary outcome was incidence of DLI-related UHRU, which was defined as any ED visit or hospital readmission that was directly attributable to the DLI. Secondary outcomes included total number of UHRU events and total unplanned days spent in the hospital secondary to the DLI. To avoid introducing bias from patients with prolonged diversion, any patient who still had their DLI 36 weeks after formation was excluded. Kaplan-Meier survival analysis was used for time-to-event analysis of DLI-related UHRU.Results/Outcomes: A total of 482 patients underwent DLI closure (Institution A, n=331 [68.7%]; Institution B, n=77 [16.0%]; and Institution C, n=74 [15.3%]). Median age at surgery was 54 years (interquartile range [IQR] 37-64) with just over half of the patients being male (n=250; 51.9%). The most common diagnosis at index operation was cancer (n=211, 43.8%), followed by ulcerative colitis (n=144, 29.9%) and diverticular disease (n=81, 16.8%).A total of 48 patients (10.0%) had at least one DLI-related UHRU event from the time of stoma creation to reversal (Figure 1). These patients had a median number of 1 (IQR 1-2) UHRU events. Across all UHRU events, patients spent a median of 5 days (IQR 3-8) in the hospital, which resulted in a total of 328 unplanned days in the hospital. The most common reasons for a DLI-related UHRU event were dehydration/acute kidney injury (n=42, 58.3%) and partial small bowel obstruction/parastomal hernia (n=23, 31.9%).Conclusion/

Discussion: DLIs carry considerable morbidity intrinsic to themselves as reflected by the high rate of UHRU between formation and reversal, without considering the additional operation and hospital stay after their reversal. Surgeons must weigh this morbidity versus the risk of an anastomotic leak when deciding whether to divert a patient.Figure 1. Kaplan-Meier curve for diverting loop ileostomy-related unplanned hospital resource utilization events.