Postpolypectomy bleeding is the most common complication of colonic polypectomy , occurring in 0.3 to 6.1 percent of polypectomies in various reports [2-7]. Bleeding can occur immediately following polypectomy or be delayed from hours to up to 29 days [2,5,6]. The severity of bleeding ranges from arterial pumping to minor oozing. The risk is related to the type and size of the polyp, the location of the polyp, the technique of polypectomy, and the coagulation status of the patient [3-5,8-11]. Bleeding can be controlled endoscopically in the majority of patients. Thus, those who perform polypectomy should also have the ability to perform hemostasis and should have the necessary tools available.
This topic will review bleeding after colonic polypectomy, including measures to decrease the risk of bleeding and the management of bleeding. Other issues related to colonoscopy and polypectomy are discussed separately. (See "Overview of colonoscopy in adults" and "Endoscopic removal of large colon polyps".)
Immediate bleeding has been observed in approximately 1.5 percent of polypectomies [2,12]. The risk is increased when blended current (rather than pure coagulation current) is used  and when the snare is pulled through larger polyps without the use of cautery ("cheese wiring") (although bleeding is not a problem with small polyps [ie, less than 1 cm] removed in this manner ). Bleeding is also more likely with large polyps (particularly if the patient is anticoagulated), polyps with a thick stalk, and polyps that are sessile .
In a multicenter study, immediate bleeding was observed in 2.8 percent of 9336 polypectomies . Independent risk factors for bleeding included age ≥65 years, cardiovascular or chronic renal disease, use of anticoagulants, polyp size greater than 1 cm, polyp morphology, poor bowel preparation, cutting mode of electrosurgical current, and inadvertent cutting of a polyp before current application. This is similar to our experience, where the risk of significant bleeding is greatest with sessile polyps larger than 2 cm in diameter, followed by those with a thick stalk; significant bleeding is unlikely to occur if a small polyp is removed with a snare without cautery.
Polyps up to 1 cm in diameter have been safely removed in patients on warfarin therapy. In some cases, the warfarin has been discontinued warfarin for 36 hours (to avoid a supratherapeutic INR). In a report of 225 polypectomies in 123 anticoagulated patients, three patients bled (one requiring treatment) . All patients in the study had prophylactic endoscopic clips applied to their polypectomy sites. In a randomized trial, 70 patients with a total of 159 polyps up to 1 cm in diameter underwent polypectomy while taking warfarin . Patients were assigned to have their polyps removed either with a cold snare technique or electrocautery. Immediate bleeding occurred in 10 of 70 patients (14 percent) and was more common in patients who had their polyps removed using electrocautery (23 versus 6 percent).