How to treat a patient with APS on warfarin with a dangerously high INR?
Most patients will not have excessive major bleeding risk unless the INR is >5. Most of the time you can instruct the patient to hold warfarin until the INR decreases to the desired range.
If you must decrease it more quickly, the patient can be given 1 mg of vitamin K orally or IV (not SC).
This will decrease the excessive anticoagulation within 12 hours without making them resistant to warfarin for several days, which happens if vitamin K is given SC. If the patient has a high INR and is severely bleeding, they need to receive fresh frozen plasma to replace coagulation factors acutely. However, this will put them at risk for clotting.
