Risks of colonoscopy

Although colonoscopy is a safe procedure in general speaking, risks exist. Risks include perforation, bleeding, complications of sedation, post-polypectomy coagulation syndrome, and rarely splenic rupture. In fact, complications of colonoscopy, particularly perforation or hemorrhage, occur most commonly in patients who undergo polypectomy. Hemorrhage after removal of a polyp is called post-polypectomy bleeding. Bleeding can occur immediately following polypectomy or be delayed up to thirty days. The risk is related to the type and size of polyp, the technique of polypectomy, and the coagulation status of the patient. In most of cases, postpolypectomy bleeding can be controlled endoscopically.

Fisher, D. A., Parra-Blanco, A., Tolliver, K. A., Feagins, L. A., Witt, D. M., Shioji, K., Liaquat, H., Hui, A. J., Shiffman, M. L., Anderson, M. A., Ferrari, E., Darvish-Kazem, S., Acosta, R. D., Ootani, A., Gibbs, D. H., Waye, J. D., Sawhney, M. S., Kim, H. S., Giorgio, P. D., … Yousfi, M. (2018, November 1). Colonoscopy, polypectomy, and the risk of bleeding. Medical Clinics of North America. https://www.sciencedirect.com/science/article/abs/pii/S0025712518300944?via%3Dihub

Hong, S. P. (2012, September). How do I manage post-polypectomy bleeding?. Clinical endoscopy. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3429752/