Comparison of Outcomes of Management of Bowel Obstruction (COMBO) Trial

About This Grant

ABSTRACT Millions of Americans each year experience adhesion-related small bowel obstruction (aSBO), a condition associated with significant morbidity and prolonged hospitalization. Adhesions formed after previous abdominopelvic surgery can cause twisting of the bowel resulting in injury and a cascade of inflammation that results in progressive bowel wall edema with narrowing of the bowel lumen. This can lead to or worsen the bowel obstruction. Evidence from both clinical practice and animal models suggests that reversing this inflammation can hasten the return of bowel function and avoid surgery for people with aSBO. For example, intravenous dexamethasone is effective in avoiding surgery in patients with a form of SBO related to malignancy (malignant ascites or metastatic disease). A Cochrane review evaluated three RCTs and found “evidence that dexamethasone…may bring about the resolution of bowel obstruction”. An underappreciated aspect of these RCTs is that almost all patients had a history of abdominopelvic surgery. Since it is difficult to distinguish the extent to which an SBO is caused by adhesions from prior surgery or mass effect related to malignant ascites or metastases, we hypothesize that dexamethasone may be efficacious in resolving aSBO as well. The proposed, Comparison of Outcomes of Management of Bowel Obstruction (COMBO) trial is a double-blinded randomized study of a short course of dexamethasone + supportive care vs. placebo + supportive care. The primary outcome is non-operative resolution of aSBO without major complications as defined using modified National Surgical Quality Improvement Program (NSQIP) criteria. Secondary outcomes–clinical, healthcare utilization and patient- reported outcomes–will be compared overall and across subgroups (e.g., based on severity of aSBO, number of prior aSBO events, sex). Reducing inflammation with dexamethasone–a readily available and safe intervention–may improve the likelihood of non-operative management of aSBO and could change the management of millions of patients with this condition.