Oral vitamin K (1 mg) was more effective than subcutaneous vitamin K at achieving a therapeutic INR the day after administration (57.7% vs 24.0%; OR 4.32; 95% CI 1.13-17.44; P=0.015).
RCT (n=51)
Yes
Does oral vitamin K improve INR correction compared to subcutaneous vitamin K in asymptomatic patients with supratherapeutic INR on warfarin?
Oral administration of 1 mg vitamin K is significantly more effective than subcutaneous administration for rapidly correcting supratherapeutic INRs in asymptomatic patients on warfarin.
Odds Ratio: 4.32 (95% CI 1.13–17.44)
Absolute Event Rate: 57.7% vs 24%
p-value: p=0.015
BACKGROUND: Excessive anticoagulation due to warfarin use is associated with hemorrhage. Subcutaneously administered vitamin K has not been evaluated for the treatment of warfarin-associated coagulopathy, yet it is widely used. OBJECTIVE: To show that oral vitamin K is more effective than subcutaneous vitamin K in the treatment of warfarin-associated coagulopathy. DESIGN: Randomized, controlled trial. SETTING: Two teaching hospitals. PATIENTS: Patients with an international normalized ratio (INR) between 4.5 and 10.0. INTERVENTION: Warfarin therapy was withheld, and 1 mg of vitamin K was given orally or subcutaneously. MEASUREMENTS: The primary outcome measure was the INR on the day after administration of vitamin K. Secondary outcome measures were hemorrhage and thrombosis during a 1-month follow-up period. RESULTS: 15 of 26 patients receiving oral vitamin K and 6 of 25 patients receiving subcutaneous vitamin K had therapeutic INRs on the day after study drug administration (P = 0.015; odds ratio, 4.32 95% CI, 1.13 to 17.44). CONCLUSION: Oral vitamin K lowers INR more rapidly than subcutaneous vitamin K in asymptomatic patients who have supratherapeutic INR values while receiving warfarin.
Crowther et al. (Tue,) conducted a rct in Warfarin-associated coagulopathy (n=51). Oral vitamin K vs. Subcutaneous vitamin K was evaluated on Therapeutic INR on the day after administration of vitamin K (OR 4.32, 95% CI 1.13-17.44, p=0.015). Oral vitamin K (1 mg) was more effective than subcutaneous vitamin K at achieving a therapeutic INR the day after administration (57.7% vs 24.0%; OR 4.32; 95% CI 1.13-17.44; P=0.015).