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Updated: Jun 22, 2026
11:17
Rapid Point-of-Care Assay of Enoxaparin Anticoagulant Efficacy in Whole Blood
Published on: October 12, 2012
Practical application of the 10-mg warfarin initiation nomogram.
Philip S Wells1, Grégoire Le Gal, Sarah Tierney
1Thrombosis Program, Division of Hematology, Department of Medicine, University of Ottawa, Ontario, Canada. pwells@ohri.ca
Summary
The 10-mg warfarin initiation nomogram effectively achieves therapeutic international normalized ratio (INR) targets within 5 days for most patients. This warfarin dosing guideline demonstrates a good safety profile in real-world clinical practice.
Area of Science:
- Pharmacology
- Clinical Medicine
- Thrombosis Management
Background:
- Warfarin therapy initiation presents clinical challenges.
- A 10-mg warfarin initiation nomogram was previously validated in a randomized controlled trial.
- Real-world efficacy and safety data for this nomogram are needed.
Purpose of the Study:
- To evaluate the efficacy and safety of a 10-mg warfarin initiation nomogram in daily clinical practice.
- To assess the achievement of therapeutic international normalized ratio (INR) targets.
- To determine the safety profile, including bleeding events, during warfarin initiation.
Main Methods:
- Retrospective cohort study of outpatients initiating warfarin and low-molecular-weight heparin.
- Analysis of 841 patients over a 24-month period.
- Assessment of nomogram adherence and INR monitoring.
Main Results:
- 640 patients (76.1%) were initiated on the 10-mg nomogram.
- 86% of nomogram-managed patients reached the therapeutic INR target (2.0-3.0) within 5 days.
- 3.7% of patients experienced an INR of at least 5.0 within the first 4 weeks.
Conclusions:
- The 10-mg warfarin initiation nomogram is effective in achieving early therapeutic INR.
- The nomogram demonstrates a favorable safety profile in real-life clinical practice.
- This dosing strategy facilitates efficient warfarin initiation.
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