Part One: Warfarin Dosing Guidelines

Management of Warfarin During Invasive Procedures

• For subtherapeutic or normal INR: Hold warfarin for 3–5 days pre-procedure

• Low Dose Heparin (LDH): Low-dose heparin (5,000 IU SQ BID); hold warfarin 3–5 days pre-procedure and begin LDH therapy 1–2 days pre-procedure

• Adjusted Dose Heparin (AdjDH): Same as LDH but higher doses of heparin (between 8,000–10,000 IU BID or TID) to achieve an aPTT in upper range of normal or slightly higher  midway between doses

• Full Dose Heparin (FDH): full doses of heparin, IV continuous infusion, to achieve a therapeutic aPTT (~1.5–2x control); implement as for LDH

• Restart heparin or warfarin post-op when considered safe to do so

Notes:

Full dose heparin should be discontinued approximately 4 hours preoperatively to allow the APTT to fall to normal during the invasive procedure. Thereafter, heparin can be restarted when considered safe to do so depending on the procedure. Adjusted dose subcutaneous heparin or low dose subcutaneous heparin should be discontinued approximately 12 hours pre-procedure.

About this presentation:

The content of these pages is from a presentation called  "Management of Oral Anticoagulant Therapy: Principles & Practice," prepared by the American Heart Association's Post-Graduate Education Committee of the Council on Clinical Cardiology.  Supported by an educational grant from DuPont Pharmaceuticals.

Authors: Jack Ansell, M.D., Jack Hirsch, M.D., Nanette K. Wenger, M.D.

Data current as of October 1999.

Endorsed by the Anticoagulation Forum and the American Heart Association Council on Atherosclerosis, Thrombosis, and Vascular Biology.

The entire PowerPoint presentation is available from the American Heart Association.