Venous thromboembolism is a common medical problem. Recently, the emphasis has been on a switch to outpatient low molecular weight heparin therapy. Previous warfarin nomograms have been developed only for inpatients. We prospectively assessed a warfarin initiation nomogram in 105 consecutive outpatients; the nomogram requires International Normalized Ratio (INR) testing on only days 3, 5, and 8. Eighty-three percent had a therapeutic INR by day 5 and 98% by day 8. There were no major bleeds and only 6 instances of INR >4.5. This outpatient warfarin nomogram appears to be safe and efficacious in obtaining timely therapeutic levels of warfarin and deserves further study.
© 2002 S. Karger AG, Basel
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Dr. Michael J. Kovacs
Room 2760, Phase 1, London Health Sciences Centre
800 Commissioners Road East
London, Ontario N6A 4G5 (Canada)
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Received: Received: October 10, 2001
Accepted in revised form: June 20, 2002
Number of Print Pages : 3
Number of Figures : 1, Number of Tables : 0, Number of References : 10
Pathophysiology of Haemostasis and Thrombosis
Official Journal of the ‘Mediterranean League against Thromboembolic Diseases’
Vol. 32, No. 3, Year 2002 (Cover Date: May-June 2002 (Released October 2002))
Journal Editor: H.C. Hemker, Maastricht
ISSN: 1424–8832 (print), 1424–8840 (Online)
For additional information: http://www.karger.com/journals/pht
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