Association between the ulcer status and the risk of delayed bleeding after the endoscopic mucosal resection of colon.

Abstract

Bleeding is the most common adverse event following colonoscopic endoscopic mucosal resection (EMR). We aimed to assess the clinical outcomes of a colon EMR according to the post-EMR ulcer status and determine the risk factors of delayed postpolypectomy bleeding (DPPB) based on the post-EMR ulcer status. The medical records and endoscopic images of patients who underwent EMR of colon polyps with diameters of ≥5mm were retrospectively reviewed by us. If any exposed vessels were observed on the post-EMR ulcer, the types of exposed vessels were classified into cut and uncut vessels. The coagulation injuries on the post-EMR ulcer were categorized as grades 1, 2, or 3. In total, 505 patients with 728 polyps were examined. Exposed vessels were present in 416 post-EMR ulcers, including cut vessels in 11 (1.5%) and uncut vessels in 405 (55.6%). With regard to coagulation injury, 113 (15.5%), 443 (60.9%), and 172 (23.6%) post-EMR ulcers had grades 1, 2, and 3 injuries, respectively. DPPB was observed in 20 lesions (2.7%). Multivariate analysis indicated that a polyp size >10mm (odds ratio [OR], 3.354; 95% confidence interval [CI], 1.229-9.154), cut vessels (OR, 18.913; 95% CI, 3.106-115.187), and grade 3 coagulation injury (OR, 16.796; 95% CI, 1.825-154.556) were associated with DPPB. Cut vessels and severe coagulation injury on post-EMR ulcers, as well as larger polyp size, are risk factors for DPPB. Careful inspection of post-EMR ulcers and prophylactic hemostasis, if necessary, may improve the clinical outcomes of colonoscopic EMR.