Overview
This is a feasibility study of uninterrupted warfarin with a one time dose of Vitamin K before a surgical procedure.
Description
Historically, warfarin is held for 5 days before a surgical procedure to obtain a safe INR (international normalized ratio) that minimizes bleeding risk. However, there is a strong rationale for continuing warfarin uninterrupted in the perioperative space and giving a one-time vitamin K dose to get a safe INR pre-operatively. This feasibility study will recruit patients who use warfarin and will measure their INR response after receiving a single pre-procedure vitamin K dose. This study will also assess the use of a one-time "loading" dose immediately post-operative to help the INR return to the therapeutic range sooner than continuing with the standard warfarin dosing.
Eligibility
Inclusion Criteria:
- Warfarin therapy for ≥3 months
- Use of home INR testing equipment
- Scheduled for a surgical procedure that requires INR ≤ 1.5 (typically achieved with warfarin interruption)
- INR ≤ 4 on day 7-10 prior to procedure
Exclusion Criteria:
- Surgical procedure does not require INR ≤1.5 (typically achieved with warfarin interruption)
- Surgical procedure with a high risk of bleeding or complications (urologic procedures, bronchoscopy, epidural injections, nerve blocks, spinal surgery)
- Warfarin therapy for \< 3 months
- Lack of English language proficiency
- Use of a Heartmate II or HVAD left ventricular assist device
- Recent thrombotic event (within 3 months)
- CHA2DS2-VASc score \>6
- INR \>4 on day 7-10 prior to procedure
- Hypersensitivity to any component of Vitamin K or simple syrup (used in the compounding process)
