Removal of small colorectal polyps in anticoagulated patients: a prospective randomized comparison of cold snare and conventional polypectomy

Gastrointest Endosc. 2014 Mar;79(3):417-23. doi: 10.1016/j.gie.2013.08.040. Epub 2013 Oct 11.


Background: The bleeding risk after cold snare polypectomy in anticoagulated patients is not known.

Objective: To compare the bleeding risk after cold snare polypectomy or conventional polypectomy for small colorectal polyps in anticoagulated patients.

Design: Prospective randomized controlled study.

Setting: Municipal hospital in Japan.

Interventions: Anticoagulated patients with colorectal polyps up to 10 mm in diameter were enrolled. Patients were randomized to polypectomy with either cold snare technique (Cold group) or conventional polypectomy (Conventional group) without discontinuation of warfarin. The primary outcome measure was delayed bleeding (ie, requiring endoscopic intervention within 2 weeks after polypectomy). Secondary outcome measures were immediate bleeding and retrieval rate of colorectal polyps.

Results: Seventy patients were randomized (159 polyps): Cold group (n = 35, 78 polyps) and Conventional group (n = 35; 81 polyps). The patients' demographic characteristics including international normalized ratio and the number, size, and shape of polyps removed were similar between the 2 techniques. Immediate bleeding during the procedure was more common with conventional polypectomy (23% [8/35]) compared with cold polypectomy (5.7% [2/35]) (P = .042). No delayed bleeding occurred in the Cold group, whereas 5 patients (14%) required endoscopic hemostasis in the Conventional group (P = .027). Complete polyp retrieval rates were identical (94% [73/78] vs 93% [75/81]). The presence of histologically demonstrated injured arteries in the submucosal layer with cold snare was significantly less than with conventional snare (22% vs 39%, P = .023).

Limitation: Small sample size, single-center study.

Conclusions: Delayed bleeding requiring hemostasis occurred significantly less commonly after cold snare polypectomy than conventional polypectomy despite continuation of anticoagulants. Cold snare polypectomy is preferred for removal of small colorectal polyps in anticoagulated patients. (

Clinical trial registration number: NCT 01553565.).

Trial registration: NCT01553565.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adenoma / surgery*
  • Aged
  • Aged, 80 and over
  • Anticoagulants / adverse effects
  • Arteries / injuries
  • Blood Loss, Surgical
  • Colon / blood supply
  • Colonic Polyps / surgery*
  • Colonoscopy / adverse effects*
  • Colonoscopy / methods*
  • Colorectal Neoplasms / surgery*
  • Female
  • Hemostasis, Endoscopic
  • Humans
  • International Normalized Ratio
  • Male
  • Middle Aged
  • Postoperative Hemorrhage / etiology*
  • Postoperative Hemorrhage / therapy
  • Rectum / blood supply
  • Vascular System Injuries / etiology
  • Warfarin / adverse effects


  • Anticoagulants
  • Warfarin

Associated data