Management of Prolonged INR

Assessment and Management

The American Geriatrics Society recommends first assessing for the presence of bleeding and risk factors for bleeding when encountering a patient with elevated INR, and determining the INR level to categorize the severity of elevation (mild: INR 3-5, moderate: INR 5-9, severe: INR >9) 1, 2
For patients with mildly elevated INR (3.0-5.0) without bleeding, the American Geriatrics Society suggests reducing or omitting the next dose of warfarin, and resuming therapy at a lower dose when INR returns to therapeutic range 1, 2
For patients with moderately elevated INR (5.0-9.0) without bleeding, the American Geriatrics Society recommends withholding 1-2 doses of warfarin, and administering vitamin K1 1.0-2.5 mg orally for patients at higher bleeding risk 1, 2
For patients with severely elevated INR (>9.0) without bleeding, the American Geriatrics Society suggests withholding warfarin therapy, and administering vitamin K1 2.5-5 mg orally 1, 2

The American College of Cardiology recommends using lower doses of vitamin K (1.0-2.0 mg) for patients with mechanical heart valves to avoid rapid reversal that could increase thrombosis risk, and targeting INR between 2.0-3.0 or 2.5-3.5 based on valve type and location 3, 4
For patients requiring urgent surgery, the American College of Cardiology suggests considering low-dose oral vitamin K (1-2.5 mg) for minor procedures with INR 1.5-1.8, and more aggressive reversal with vitamin K and clotting factors for major procedures 5, 6
For elderly patients, the American Geriatrics Society recommends considering lower doses of vitamin K (1.0 mg) due to increased sensitivity, and more frequent monitoring due to higher bleeding risk 2

After INR normalization, the American Geriatrics Society suggests identifying and addressing the underlying cause of the elevation, and adjusting maintenance dose of warfarin if necessary 1, 2
The American Geriatrics Society recommends increasing frequency of INR monitoring until stability is achieved, and educating patients about medication interactions, dietary consistency, and signs of bleeding 2