A safe, effective, and easy to use warfarin initiation dosing nomogram for post-joint arthroplasty patients

J Arthroplasty. 2010 Jan;25(1):121-7. doi: 10.1016/j.arth.2008.09.015. Epub 2008 Dec 5.

Abstract

Venous thromboembolism (VTE) is a complication after joint arthroplasty, and pharmacologic prophylaxis is recommended to reduce this risk. Warfarin is often used, but initial dosing and management can be difficult. We studied a single-center prospective cohort of consecutive (n = 351) post-joint arthroplasty/revision patients who were initiated on warfarin using a new initiation nomogram and then discharged to home with home health services. The mean time to an international normalized ratio (INR) of 2.0 or higher was 5 days, with a mean INR of 2.1 on the fifth postoperative day. Two patients (0.6%) had an INR higher than 5 in the first 10 days of therapy. Adverse events were uncommon: 4 patients (1.14%) had VTE, 1 had major bleeding episode, and 6 patients (1.7%) had minor bleeding. A specific warfarin dosing nomogram managed by an anticoagulation service and used in joint arthroplasty/revision patients who are discharged to home with home health services leads to effective anticoagulation with few associated adverse events.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Anticoagulants / administration & dosage*
  • Anticoagulants / adverse effects
  • Arthroplasty, Replacement, Hip* / adverse effects
  • Arthroplasty, Replacement, Knee* / adverse effects
  • Female
  • Humans
  • International Normalized Ratio
  • Male
  • Middle Aged
  • Nomograms*
  • Venous Thromboembolism / etiology
  • Venous Thromboembolism / prevention & control*
  • Warfarin / administration & dosage*
  • Warfarin / adverse effects
  • Young Adult

Substances

  • Anticoagulants
  • Warfarin