The risk factors for delayed bleeding after endoscopic resection of colorectal tumors: a meta-analysis.

Introduction: The most common complication of post-colorectal endoscopic resection is delayed bleeding. The assessment of risk factors for delayed bleeding provides important and useful information in standard clinical operations. The risk factors have been previously reported; however, they remain inconsistent across different studies.

Areas Covered: In this meta-analysis, the patient conditions, lesion-related factors, and operation-related factors were compared between delayed bleeding and no bleeding. PubMed, Cochrane, Embase, China National Knowledge Infrastructure (CNKI), and Wanfang Database were searched to identify eligible studies. Pooled odds ratio (OR) and 95% confidence intervals (CI) were calculated along with heterogeneity.

Expert Opinion: This study is the first meta-analysis to investigate risk factors for colorectal delayed bleeding. We found several risk factors contributing to this condition: colorectal tumors located in the proximal colon, a history of antithrombotic drug use, high-grade intraepithelial neoplasia or early cancer, piecemeal resection, intraoperative hemorrhage, no clip placement, and severe submucosal fibrosis. Despite our findings, we also conclude that more high-quality, large-scale clinical randomized controlled studies are needed due to limited retrospective studies at present. Future therapeutic colonoscopies should focus on precise diagnosis, treatment safety, and management during the perioperative period.