Evaluation of Nexpowder Application to Prevent Delayed Bleeding After Colorectal Endoscopic Mucosal Resection

Evaluation of Nexpowder Application to Prevent Delayed Bleeding After Large Colorectal Endoscopic Mucosal Resection

Delayed bleeding is the most frequent (5 to 15%) and challenging complication after large colorectal polypectomy. Different preventive treatments, such as the prophylactic use of clips, have been tried to prevent the occurrence of delayed bleeding, but to date, no treatment has clearly shown its effectiveness. In addition, preventive hemostasis with clips is difficult and costly. A newly developed endoscopic hemostatic powder generating gelation effect (Nexpowder) may be an effective alternative to prevent post polypectomy bleeding in patients treated by endoscopic mucosal resection (EMR) for large superficial colorectal lesions.

Inclusion Criteria:

• More than 18 years old

• Indication of EMR for a superficial nonpedunculated colorectal lesion

• Higher risk of bleeding (score GSEED RE2 ≥ 7*)

  *Score GSEED RE2 (Albeniz et al GIE 2020):

• Proximal location (cecum to transverse included) : 3 points

• Antiplatelets or anticoagulation use: 3 points

• Lesion size ≥ 40 mm: 1 point

• ASA III-IV or major comorbidity: 1 point

Exclusion Criteria:

• Patients susceptible to allergic reactions to certain substances in Nexpowder
• More than one colorectal lesion
• Suspicion of invasive cancer (Kudo V, Sano IIIb, Connect III), macronodular more than 1 cm, depressed area (Paris IIc)
• Pedunculated polyps (Ip from Paris classification) or ulcerated polyps (III)
• Recurrent or residual lesion after endoscopic or surgical resection
• Poor bowel preparation quality (Boston score < 6)
• Inflammatory bowel disease (IBD)
• Patients with a platelet count of 50,000/mm3 or less
• Patients with acquired (non-medicated) or inherited bleeding disorders
• Patients with advanced cancer or inflammatory bowel disease, including ulcerative colitis (with colonic involvement)
• Contraindication to general anesthesia
• Women who are pregnant or who wish to become pregnant during the study or women who are breastfeeding.
• Children, immunocompromised persons and persons over 90 years of age
• Patients already participating or scheduled to participate in other clinical trials
• Lesion previously resected by endoscopy
• Patient with an initial metastatic lesion before colonoscopy
• Patient unable to give personal consent
• Lack of signed informed consent