Underwater Endoscopic Mucosal Resection Versus Metal Clips With Hot Snare Polypectomy for Resection of Big Pedunculated Colorectal Polyps：a Randomized Controlled Trial

Underwater Endoscopic Mucosal Resection Versus Metal Clips With Hot Snare Polypectomy for Resection of Big Pedunculated Colorectal Polyps：a Randomized Controlled Trial

Underwater Endoscopic Mucosal Resection Versus Metal Clips With Hot Snare Polypectomy for Resection of Big Pedunculated Colorectal Polyps：a Randomized Controlled Trial

Endoscopic resection of pedicled polyps mainly focuses on how to prevent bleeding, and also needs to pay attention to the convenience of resection and the integrity of resection, which means that different endoscopic resection strategies should be adopted for pedicled polyps with different pedicle sizes. The head larger than 20mm or pedicle larger than 5mm are defined as large pedicle polyps, which are at greater risk of bleeding. Current guidelines recommend hot removal by snare following preoperative saline injection, ligation of the pedicle with a nylon ring or metal clip, depending on the size of the polyp head and pedicle. However, the use of snares and metal clamps does not appear to reduce delayed postoperative bleeding, and the technical requirements of nylon ligation are relatively high. Recent studies have found that Underwater endoscopic mucosal resection (UEMR) is also safe and effective for the treatment of large and medium colorectal stemless polyps. Therefore, it is still necessary to further explore new safe and effective endoscopic resection strategies and techniques.

underwater endoscopic mucosal resection achieves similar rates of complete resection with comparable safety, with lower rates of recurrence and fewer repeat procedures.

Current guidelines recommend preoperative hot snare polypectomy after preoperative saline injection, nylon ring, or metal clip ligation of the tip and pedicle of the polyps

Immediate bleeding was defined as an intraoperative bleeding immediately after polypectomy. Level 2, Level 1 was defined as continuous exudation for 1 minute, and level 2 was defined as active blood spray

Any symptoms of gastrointestinal bleeding (e. g. hematochezia) occurred within 30 days after polypectomy and were classified as mild or severe according on the severity of the bleeding

Inclusion Criteria: 1. Patients undergoing endoscopic resection of small and medium pedicled polyps in the First Affiliated Hospital of Ningbo University from October 2023 to August 2026; 2. Age 18-75 years old; 3. Patients who voluntarily agreed to participate in this study and signed informed consent. Exclusion Criteria: 1. Persons under 18 years of age 2. Persons unwilling or unable to provide informed consent 3. Treatment or radiotherapy for malignant diseases, severe chronic heart or lung diseases, coronary or cerebrovascular events requiring hospitalization within the last 3 months 4.Malignant polyps have infiltrated the pedicle 5. Abdominal symptoms such as severe abdominal pain, abdominal distension, and nausea 6.Patients with inadequate intestinal preparation 7. Patients with lifelong anticoagulant therapy or severe bleeding diseases, patients who have recently taken anticoagulant drugs or antiplatelet drugs (within 1 week) 8.Pregnant or lactating