|A: The risk of withdrawing anticoagulation therapy with coumadin, aspirin or any other antiplatlet therapy must be weighed against the relative risks and benefits. The original indication for the blood thinner and the risks associated with its withdrawal (blood clots, unstable angina, heart attack, stroke etc.) must be weighed against the strength of the indication for the endoscopic procedure. Sometimes colonoscopy can be performed without stopping the anticoagulation or antiplatelet therapy at all. Another alternative is for the physician to prescribe Heparin or Lovenox injection therapy pre and postoperatively to replace coumadin in the high risk patient. In the final analysis, each physician must help his patient to decide on an appropriate course of action. As with so many therapeutic decisions in medicine there is no single right answer.
A2: The duration of time for discontinuation of coumadin therapy prior to an endoscopic procedure depends on several factors. The level of the protime inr blood test results and the preoperative anticoagulation treatment goals will determine how many days it will take for the coumadin to get out of the system. The doctor can hurry this process by administering Vitamin K, or in very urgent circumstances by transfusing fresh frozen plasma if active bleeding is suspected. There are, however, additional risks associated with these approaches. If for example, the usual PT inr blood test is 2.0 then withholding the coumadin for 3-4 days may be sufficient. If the PT inr result was 3.0 then a longer period of avoidance may be required. Individual circumstances however may differ and the physician can always check the protime preoperatively for a definitive confirmation. This may be necessary if a biopsy or removal of a polyp is being considered.