What to do for a patient with an elevated INR (International Normalized Ratio) of 6.9 on Coumadin (warfarin) 2.5 mg?

Management of Elevated INR of 6.9 on Warfarin 2.5 mg

For a patient with an INR of 6.9 on warfarin 2.5 mg, we recommend holding warfarin, administering 2.5-5 mg oral vitamin K, and monitoring INR every 24 hours until it returns to therapeutic range.

Immediate Management

The risk of major bleeding increases exponentially when INR exceeds 4.5 and rises steeply above an INR of 6.0 1. For an INR of 6.9, the following steps should be taken:

1. Hold warfarin doses immediately
2. Administer vitamin K:
   • If no active bleeding: 2.5-5 mg oral vitamin K 2
   • If bleeding present: 5-10 mg intravenous vitamin K 2
3. Monitor INR within 24 hours after vitamin K administration 2

Additional Considerations Based on Clinical Status

For patients WITHOUT active bleeding:

• Oral vitamin K (2.5-5 mg) is preferred over intravenous administration to avoid risk of anaphylaxis 2
• Avoid high doses of vitamin K (>5 mg) in patients with mechanical heart valves as it may cause resistance to warfarin for several days 2
• Consider hospital admission for monitoring if the patient has additional risk factors for bleeding (elderly, renal failure, alcohol use) 3

For patients WITH active bleeding:

• Administer 5-10 mg vitamin K intravenously 1, 2
• Consider prothrombin complex concentrate (PCC) based on INR level:
  • For INR >6: 50 units/kg (maximum 5000 units) 2
• Fresh frozen plasma may be considered if PCC is unavailable, though it is less effective 1
• Monitor INR every 6-12 hours until stabilized 2

Resuming Anticoagulation

Once the INR returns to therapeutic range:

1. Restart warfarin at a reduced dose (10-20% lower than previous dose) 2
2. Monitor INR more frequently initially (2-3 times per week) until stable 4
3. Investigate potential causes of elevated INR:
   • Drug interactions
   • Changes in diet
   • Acute illness
   • Diarrhea (can significantly elevate INR) 5
   • Alcohol consumption 3

Special Considerations

• Mechanical heart valves: Complete reversal should be avoided unless life-threatening bleeding is present 2
• Elderly patients (≥75 years): Consider a lower target INR of 2.0-2.5 when resuming therapy 2, 6
• Concurrent antiplatelet therapy: Increases bleeding risk; may require lower target INR 2

Follow-up Plan

1. Verify INR 24 hours after vitamin K administration 2
2. Continue daily INR monitoring until stable in therapeutic range
3. Adjust warfarin dose upon reinitiation (generally 10-20% reduction) 2
4. Educate patient on importance of medication adherence and consistent vitamin K intake 2

Common Pitfalls to Avoid

• Excessive vitamin K: Using doses >5 mg can cause warfarin resistance for days 2
• Delayed monitoring: Failure to check INR within 24 hours after intervention
• Inadequate investigation of the cause of elevated INR
• Restarting at the same dose: Failure to reduce warfarin dose when resuming therapy
• Overlooking diarrhea as a potential cause of INR elevation 5

Remember that the goal is to safely return the patient to therapeutic anticoagulation while minimizing both bleeding and thrombotic risks.