R. Behman1, P. Karanicolas1, A. Nathens1, J. Jung1, N. Look Hong1 1University of Toronto,Department Of Surgery,Toronto, Ontario, Canada
Introduction:
Adhesive small bowel obstruction (aSBO) is one of the most common reasons for general surgery admission. Current guidelines advocate for a trial of conservative management (TCM) in patients without signs of bowel ischemia. However, emerging evidence suggests conservative management may be associated with increased risk of recurrence. Furthermore, when TCM fails, patients undergoing delayed operative management experience increased mortality and morbidity. The purpose of this decision analysis is to compare two competing strategies for the management of aSBO: early operative management (EOM) and the current standard of care, TCM.
Methods:
We performed a decision analysis with microsimulation and Markov modeling to compare short- and long-term outcomes following treatment with either TCM or EOM at the index admission for aSBO. We defined EOM as operative management within 24 hours. The TCM strategy could succeed or fail and result in delayed operation (>24 hours). Patients’ disease course was modeled over a 10-year time horizon using probabilities derived from 18 previously published studies. Outcomes modeled included the total number of recurrences, complications, and bowel resections as well as the overall probability of an aSBO-related mortality associated with each treatment strategy. Sensitivity analyses were performed to test the robustness of the model.
Results:
Over a 10-year time horizon, patients treated with EOM are less likely to experience a recurrence of aSBO than those treated with TCM (36% vs. 52%) and are 36% less likely to experience two or more recurrences. Patients treated with EOM are more likely to undergo bowel resection (32% vs 16%) and are more likely to experience complications (34% vs. 24%). A sensitivity analysis was performed to account for potential confounding by indication associated with the use of retrospective data. When controlling for patients in the EOM arm who were likely assigned to this treatment due to signs of bowel ischemia, the two treatment strategies had similar complication rates (29% with EOM and 26% with TCM). Peri-admission mortality over the 10-year time horizon was also similar between the two groups (0.06 vs 0.056).
Conclusion:
Over a 10-year time horizon, EOM is associated with lower recurrence. Complication rates are similar in the two treatment strategies when controlling for patients who likely had signs of bowel ischemia at pesentation. EOM may be a suitable treatment strategy for patients with aSBO without signs of bowel ischemia. Future studies should focus on cost-effectiveness in order to further assess the impact of different treatment strategies on the healthcare system and to effect changes in clinical practice.