From the Guidelines
For procedures with low risk of bleeding, it is recommended to hold Warfarin (Coumadin) for up to 1 week and allow the INR to normalize without substituting UFH, as stated in the 2014 AHA/ACC/HRS guideline for the management of patients with atrial fibrillation 1. The goal is to achieve an INR of 1.5 or less on the day of the procedure.
- Check the INR the day before or the morning of the procedure to ensure it has reached the target level.
- If the INR is still above 1.5, consider administering low-dose oral vitamin K (1-2 mg) to reverse the anticoagulation more quickly. For patients at low risk of thromboembolism, stopping warfarin for up to 1 week and allowing the INR to normalize without substituting UFH is a recognized approach, as per the 2014 AHA/ACC/HRS guideline 1.
- Warfarin is then resumed after adequate hemostasis has been achieved.
- This approach balances the need to reduce bleeding risk during the procedure while minimizing the time the patient is without anticoagulation. The shorter hold time for low-risk procedures reflects the lower likelihood of significant bleeding complications, while still allowing enough time for the anticoagulant effect to diminish sufficiently, as noted in the 2014 AHA/ACC/HRS guideline 1.
- The use of bridging anticoagulation with UFH or LMWH may be considered for patients at higher risk of thromboembolism, but this is not typically necessary for low-risk procedures.
- The 2003 American Heart Association/American College of Cardiology Foundation guide to warfarin therapy also provides guidance on the management of anticoagulated patients who require surgery or other invasive procedures, but the 2014 AHA/ACC/HRS guideline is more recent and takes precedence 1.
From the Research
Recommended Duration to Withhold Warfarin
- The recommended duration to withhold Warfarin (Coumadin) prior to a procedure with low risk of bleeding is not explicitly stated in all studies, but according to 2, for low-risk procedures, it is not necessary to adjust anticoagulation.
- However, for procedures that incur a high risk of bleeding, Warfarin should be discontinued four to five days beforehand 2.
- Another study 3 recommends that Warfarin should be discontinued or international normalized ratio (INR) be normalized to 1.4 or less for high-risk procedures and 2 or less for low-risk procedures based on risk factors.
- It is essential to consider the patient's risk for thromboembolic events balanced against the risk for perioperative bleeding when deciding whether to interrupt anticoagulant therapy 4.
Considerations for Withholding Warfarin
- Patient characteristics, such as age, renal function, and drug interactions, must be considered when deciding whether to withhold Warfarin 5.
- The type of procedure and its associated bleeding risk should also be taken into account when making this decision 5, 3.
- For patients on Warfarin with a high risk for thromboembolic events, a perioperative bridging therapy with a low-molecular-weight heparin may be recommended 6, 5.