Colonoscopy with polypectomy in anticoagulated patients.

BACKGROUND: According to current practice guidelines for performance of colonoscopy in patients requiring long-term anticoagulation, polypectomy is considered a high-risk procedure for which anticoagulation must temporarily be discontinued. However, these guidelines are based on expert opinion, and the bleeding risk after polypectomy in anticoagulated patients is not known. OBJECTIVE: Measure the risk of postpolypectomy bleeding in patients who undergo colonoscopic polypectomy while anticoagulated. DESIGN: Retrospective review of patients who underwent polypectomy without discontinuation of anticoagulation. SETTING: Veterans Administration Palo Alto Health Care System. PATIENTS: Forty-one polypectomies were performed in 21 patients. All patients had been receiving long-term anticoagulation with warfarin; the average international normalized ratio was 2.3 (range 1.4-4.9; normal 0.9-1.2). To prevent supratherapeutic anticoagulation, warfarin was withheld for 36 hours before the procedure while the patients were on a liquid diet. The average polyp size was 5 mm (range 3-10 mm). INTERVENTIONS: All patients underwent polypectomy followed immediately by prophylactic application of one or two clips to prevent bleeding. MAIN OUTCOME MEASUREMENTS: Rate of postpolypectomy bleeding. RESULTS: There were no episodes of postpolypectomy bleeding. The 95% CI for the risk of bleeding was 0% to 8.6% when analyzed per polypectomy and 0% to 15% when analyzed per patient. LIMITATIONS: Small single-center retrospective study. CONCLUSIONS: Our experience suggests that small polyps can be removed with a very low risk of bleeding when clips are applied immediately after polypectomy. If these results can be confirmed in a larger multicenter study, our protocol may become an alternative to withholding anticoagulation in patients at high risk of thrombosis.