Incidence and risk factors of delayed postpolypectomy bleeding: a retrospective cohort study

Delayed bleeding is a serious complication that occurs after polypectomy. Many risk factors for delayed bleeding have been suggested, but there is little analysis of procedure-related risk factors. The purpose of this study is to identify a wide range of risk factors for delayed postpolypectomy bleeding (DPPB) and analyze the correlations of those potential DPPB risk factors.

In this retrospective cohort study, 5981 polypectomies in 3788 patients were evaluated between January 2010 and February 2012. Patient-related, polyp-related, and procedure-related factors were evaluated as potential DPPB risk factors.

Delayed bleeding occurred in 42 patients (1.1%). Multivariate analysis revealed that polyp size >10 mm [odds ratio (OR), 2.785; 95% confidence interval (CI), 1.406-5.513; P=0.003], location in the right hemi-colon (OR, 2.289; 95% CI, 1.117-4.693; P=0.024), and endoscopist's experience (<300 total cases of colonoscopy performed; OR, 4.803; 95% CI, 2.631-8.766; P=0.001) were significant risk factors for DPPB. Especially protruded type polyps (Ip, Isp) larger than 1 cm in the right-side colon were associated with increased risk. Right-side polypectomy by a nonexpert endoscopist was a significant risk factor for DPPB, especially with procedures in the cecum area. Taking the 1.5% DPPB incidence as cutoff value, the learning curve of colonoscopic polypectomy may be estimated as 400 cases of polypectomy.

Polyp size, endoscopist's experience, and right hemi-colon location were identified as potential risk factors for DPPB development.