The Effect of Hyperosmolar Water-Soluble Contrast for the Management of Adhesive Small-Bowel Obstruction: A Systematic Review and Meta-Analysis

INTRODUCTION: Guidelines recommend using water-soluble contrast (WSC) to treat adhesive small-bowel obstruction (aSBO). Its effectiveness is uncertain. METHODS: A systematic review and meta-analysis was performed (January 1, 1990 to November 1, 2021). Study quality was assessed by the Cochrane risk-of-bias and the Newcastle-Ottawa tools. Enhanced versions of Consolidated Standards of Reporting Trials and Strengthening the Reporting of Observational Studies in Epidemiology checklists were also included. Randomized controlled trials (RCTs) and observational studies were analyzed separately. The therapeutic effect of WSC was assessed by operative rate and hospital length of stay (HLOS) in nonsurgical patients. Rate of bowel resection, complication, mortality, time-to-operation, and quality-of-life assessments were also analyzed. RESULTS: We identified 11 eligible RCTs that included 817 patients and 9 observational studies of 3,944 patients. HLOS in nonsurgical patients decreased by 1.95 days (95% CI 0.56 to 3.3) in the RCTs and could not be assessed in the observational studies. The RCTs showed no effect of WSC on operative rate, but there were fewer operations in the WSC group (11%) compared with controls (16%) within the observational studies (risk ratio 0.56, 95% CI 0.39 to 0.82). There was no effect of WSC on rate of bowel resection, complication, or mortality. Additional outcomes could not be assessed given insufficient reporting. There was substantial heterogeneity among the studies, in part, due to a lack of standardized WSC protocols (Fig. 1).CONCLUSION: Operative rate and HLOS in nonsurgical patients may be reduced by the administration of WSC in aSBO. The current literature is heterogeneous with considerable design limitations. High-quality RCTs are needed using standardized protocols to determine the true benefits of WSC for the management of aSBO.