Conservative treatment of overanticoagulated patients

To determine the outcome of over-anticoagulated patients who were treated with vitamin K and those who were treated conservatively by holding doses and increasing monitoring frequency. A secondary objective was to compare conservative management with American College of Chest Physicians (ACCP) treatment guidelines when followed.

Retrospective chart review of all patients with international normalized ratios (INRs) of 6 or greater and concurrently receiving warfarin between November 1993 and February 1994.

A Veterans Affairs Medical Center providing inpatient and outpatient care. Patients receiving warfarin are managed by an established anticoagulation clinic.

Fifty-one consecutive patients receiving warfarin who had an INR of 6 or greater were reviewed.

Data collection included INR, risks for bleeding, indication for anticoagulation, interventions, and patient outcomes.

INRs ranged from 6.1 to 81.8. Forty-eight patients (94%) did not receive vitamin K; they were treated by withholding doses and increasing monitoring frequency. One developed minor bleeding. Three patients (6%) received vitamin K. Two of these patients died of unrelated problems. The third patient required 47 days of heparin therapy prior to achieving therapeutic oral anticoagulation.

This trial showed that conservative treatment of nonbleeding overanticoagulated patients is safe. A prospective trial comparing the ACCP guidelines with a conservative approach is needed.