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Published on: August 1, 2019
Colonoscopy with polypectomy in anticoagulated patients
1Stanford University, and Veterans Administration Palo Alto Health Care System, 3801 Miranda Avenue-G1 111, Palo Alto, CA 94305, USA.
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.
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