Post-Polypectomy Bleeding: Is It Normal?

What Polypectomy is and why it can bleed

Polypectomy is the endoscopic resection of polypoid mucosal lesions, most commonly in the colorectum, performed during colonoscopy. The technique involves removal of the polyp using a diathermic snare (cold or with electrocautery) or, for larger lesions, endoscopic mucosal resection (EMR).

Bleeding originates from injury to submucosal vessels at the resection site. Its occurrence depends on several variables:

• Polyp size and morphology (large pedunculated polyps and non-pedunculated lesions ≥20 mm in the right colon carry higher risk)
• Resection technique: pure cutting current is associated with a higher risk of immediate bleeding, while pure coagulation current correlates more often with delayed bleeding
• Ongoing antiplatelet or anticoagulant therapy at the time of the procedure
• Patient comorbidities, including chronic kidney disease and coagulopathies

Immediate vs delayed bleeding

Within digestive endoscopy, it is useful to distinguish two distinct clinical presentations, both included under the umbrella of bleeding after polypectomy.

Immediate bleeding occurs during the procedure itself and is directly visualized by the endoscopist, who can treat it in real time with mechanical or pharmacological hemostasis. With cold snare technique, incidence is generally below 1%, while it is more frequent with hot snare polypectomy of large pedunculated polyps.

Delayed post-polypectomy bleeding (DPPB) typically occurs within 14 days of the procedure, most often between the first and second week, presenting as hematochezia or melena. It is the most common major adverse event of endoscopic resection and, according to the latest ESGE guideline (Ferlitsch et al., Colorectal polypectomy and endoscopic mucosal resection: ESGE Guideline – Update 2024, Endoscopy 2024;56:516–545), is the focus of the leading prevention and management recommendations.

When bleeding is considered normal

Minimal, self-limiting bleeding, with traces of blood in the first bowel movements after the procedure, generally falls within the expected clinical course and requires no intervention. The same applies to mild oozing observed by the endoscopist during the procedure, if promptly controlled with standard hemostatic maneuvers.

It becomes a warning sign, however, when the following occur:

• Heavy or persistent rectal bleeding beyond 24-48 hours
• Onset of melena, dizziness, tachycardia, or hypotension
• Severe abdominal pain associated with blood loss
• More than two to three bloody bowel movements within a few hours

In these cases, prompt clinical and, if needed, endoscopic reassessment is indicated, since delayed treatment of significant DPPB can lead to the need for transfusion or, rarely, surgical or angiographic intervention.

Risk factors and prevention strategies

The 2024 ESGE guideline recommends prophylactic closure of the mucosal defect after EMR of non-pedunculated lesions ≥20 mm in the right colon, where the risk of delayed bleeding is higher. For large pedunculated polyps (head ≥20 mm or stalk ≥10 mm), prophylactic mechanical hemostasis and/or injection of diluted adrenaline before or after resection is generally recommended.

Other key elements in prevention include:

• Pre-procedural assessment of antithrombotic therapy, with possible interruption or bridging according to ESGE recommendations and relevant scientific society guidelines
• Selection of the most appropriate resection technique based on polyp size, morphology, and location
• Adequate endoscopist experience in managing complex lesions