The risk factors for post-polypectomy bleeding and establishment of a risk-scoring model for small colorectal polyps (<1.5cm) in an ambulatory surgery center: a retrospective analysis

Background: As one of the most common complications of colonoscopy, the risk factors of post-polypectomy bleeding (PPB) has been rarely explored in an ambulatory surgery unit. We aim to develop a risk-scoring model to predict the risk of PPB forsmall colorectal polyps (<1.5cm) in an ambulatory surgery unit. Methods: The patients with single small colorectal polyps (<1.5cm) who underwent endoscopic polypectomy in the Ambulatory Surgery Center of our hospital between January 2014 and June 2017 were included and retrospectively reviewed. We analyzed patient’s clinical characteristics, morphological and pathological characteristics of polyps, polypectomy techniques, and the occurrence of PPB. Risk factors of PPB were identified with a multivariable logistic regression model. In addition, a risk-scoring system was developed and validated eventually. Results: Among the 771 patients enrolled, 26 (3.4%) patients suffered PPB. The male gender, elderly age (≥ 60 years), using hot biopsy forceps as polypectomy technique adenoma in histopathology, complicated withhypertension, use of anticoagulant or antiplatelet agents, and early excessive activities significantly increased the risk of PPB (P＜0.05) as indicated by the results of multivariable logistic regression analysis. The area under the ROC curve (AUC) in the model group (0.890) and validation group (0.924) indicated that the risk-scoring model could predict the occurrence of PPB effectively. Conclusions: This risk-scoring method may help to predict the risk of PPB forsmall colorectal polyps, fit well in the Ambulatory Surgery Center, and provide a new approach to help reduce the incidence of hemorrhage after colorectal polypectomy.Trial registration: This study was retrospectively registered and approved by the Ethics Committee of West China Hospital of Sichuan University (IRB number: ChiCTR1800020201).