Standardized selective clipping for persistent immediate bleeding after cold snare polypectomy of small colorectal polyps: a prospective cohort study

Abstract

Background and study aims: Delayed bleeding after cold snare polypectomy of 4–9 mm nonpedunculated colorectal polyps is rare, but persistent immediate bleeding is relatively common and lacks a standardized management framework. We prospectively evaluated 30-day outcomes of a standardized selective clipping protocol for persistent immediate bleeding after cold snare polypectomy. Patients and methods: In this prospective single-center cohort study, consecutive adults with at least one eligible 4–9 mm nonpedunculated colorectal polyp resected by cold snare polypectomy between 1 January and 31 December 2024 were enrolled. All bleeding defects were irrigated and observed for 60 seconds, and clips were applied only for persistent oozing according to a standardized selective clipping protocol. The primary endpoint was delayed bleeding within 30 days after polypectomy. Results: Among 2176 patients with 4343 polyps, 315 patients (14.5%) and 369 lesions (8.5%) required clipping for persistent immediate bleeding. Delayed bleeding occurred in 5 patients (0.23%), all confirmed by repeat colonoscopy. Patient-level delayed bleeding rates were 0.63% (2/315) in the selective-clipping group and 0.16% (3/1861) in the group without clipping. Lesion-level delayed bleeding rates were 0.54% (2/369) in clip-treated lesions and 0.13% (5/3974) in unclipped lesions. Exploratory analysis suggested chronic kidney disease and five or more synchronous polyps as candidate risk factors. Conclusions: Under a standardized selective clipping protocol, delayed bleeding after cold snare polypectomy of 4–9 mm nonpedunculated colorectal polyps was infrequent in both groups, and all confirmed bleeding events were successfully managed endoscopically.