Urgent Colonoscopy in Hospitalized Patients with Hematochezia: A Systematic Review and Meta-Analysis

Introduction: Lower gastrointestinal bleeding is a common cause of morbidity and mortality. Colonoscopy is indicated in all hospitalized patients with lower gastrointestinal bleeding, yet the time frame for performing colonoscopy remains unclear. Prior studies of outcomes in urgent versus elective colonoscopy have yielded conflicting results and were often underpowered. We performed a meta-analysis to compared outcomes between urgent and elective colonoscopy, including localization of bleeding sources, use of therapeutic interventions, re-bleeding rates, transfusion rates, adverse events, and mortality, in hospitalized patients with hematochezia. Methods: Systematic review and meta-analysis of studies comparing urgent and elective colonoscopy in patients with hematochezia. Results: Thirteen studies met inclusion criteria, with a total sample size of 10,219 patients in the urgent colonoscopy arm and 14,354 patients in the elective colonoscopy arm. Urgent colonoscopy was associated with increased use of endoscopic therapeutic intervention (RR 1.87 95% CI 1.19-2.92). There were no differences in bleeding source localization (RR 1.04 95% CI 0.92-1.19), adverse event rates (RR 1.05 95% CI 0.65-1.71), re-bleeding rates (RR 1.14 95% CI 0.74-1.78), transfusion requirement (RR 1.02 95% CI 0.73-1.41), or mortality (RR 1.17 95% CI 0.45-3.02). Conclusion: Urgent colonoscopy was associated with increased use of therapeutic intervention without a significant difference in source localization, adverse events, or mortality. Urgent colonoscopy should be considered for early risk stratification in hospitalized patients with hematochezia, as it is safe and well tolerated.