Optimal timing of anticoagulation pre- and post-colonoscopy with polypectomy

An increasing number of patients are treated with anticoagulation for many medical conditions. Our practice is to suspend warfarin 5-7 days, aspirin 3 days, and clopidogrel (Plavix) 7 days prior to colonoscopy that may require polypectomy. Generally, we accept an INR of ≤1.5 as safe. However, there are no published case series documenting when it is safe to resume these medications after polypectomy. Therefore, the management of anticoagulation after polypectomy varies. We sought to evaluate the safety of our practice with regard to anticoagulation and polypectomy.

We conducted a retrospective review of all patients over the age of 18 who underwent colonoscopy with polypectomy while on anticoagulation for various medical comorbidities at our institution over a 15-month period (July 2007 to September 2008). All morbidity and mortality that occurred for the first 3 weeks post-polypectomy was recorded. The Mann-Whitney test was performed using SPSS 15.5.

From July 2007 to September 2008, we performed 579 colonoscopies with polypectomy on patients who were on anticoagulation therapy during the study period. Seven (1.2%) patients presented to the Emergency Room or were hospitalized within 3 weeks after polypectomy for lower gastrointestinal bleeding. Distribution of anticoagulants was listed: 2 (28.6%) patients on warfarin, 4 (57.1%) on aspirin, and 1 (14.3%) on clopidogrel. Warfarin was held for, on average, 4 days pre-polypectomy and 1 day post-polypectomy. Aspirin was held, on average, 3 days both pre- and post-polypectomy. Clopidogrel was held, on average 6.5 days pre-polypectomy but restarted immediately post-polypectomy. No statistically significant difference was found between the number of days that anticoagulation was held pre- or post-polypectomy in individuals who did and did not bleed.

We found that our practice of resuming anticoagulation or antiplatelet agents (warfarin, aspirin, and clopidogrel) post-polypectomy was safe and did not prove to significantly affect the post-polypectomy rate of hemorrhage.