Adjustment of maintenance warfarin dosing based on the RE-LY trial

INR	Adjustment in total mg of warfarin per week
≤1.5	Increase 15 percent per week
1.51 to 1.99	Increase 10 percent per week*
2 to 3	No change
3.01 to 4	Decrease 10 percent per week
4.01 to 4.99	Hold one dose; restart with dose decreased by 10 percent per week
5 to 8.99	Hold until INR is 2 to 3; restart with dose decreased by 15 percent per week

The table provides an algorithm for monitoring and adjustment of maintenance warfarin dosing with a goal of maintaining the INR between 2 and 3. The maintenance dose algorithm requires that INR measurements are made at a maximum interval of every four weeks, with at least weekly monitoring for out of range INRs (<2 or >3). All percent changes in warfarin dosage are adjusted based on the current INR value and calculated based upon the sum of the previous seven days of warfarin doses (also known as mg of warfarin per week). The increase or decrease in warfarin dose per week is distributed over the following week, preferably as evenly as possible to avoid large fluctuations.
This algorithm is not applicable to selecting a warfarin starting dose or for adjusting the starting dose during the first week of treatment. Refer to UpToDate content on the use of warfarin for details.

RE-LY: Randomized Evaluation of Long-term anticoagulation therapY; INR: international normalized ratio.
* As an example, a patient taking 30 mg of warfarin per week with an INR of 1.8 would increase the dose by 10 percent (increase by 3 mg to 33 mg per week). The new weekly dose (33 mg) could be distributed as 5 mg daily on six days of the week and 3 mg on the remaining day. Several alternate means of distributing the dose could also be used (eg, 5 mg daily on five days of the week and 4 mg daily on the remaining two days).

Data from: Van Spall HG, Wallentin L, Yusuf S, et al. Variation in warfarin dose adjustment practice is responsible for differences in the quality of anticoagulation control between centers and countries: an analysis of patients receiving warfarin in the randomized evaluation of long-term anticoagulation (RE-LY) trial. Circulation 2012; 126:2309.

Graphic 87435 Version 5.0

خرید پکیج

Adjustment of maintenance warfarin dosing based on the RE-LY trial