UMEM Educational Pearls

Category: Pharmacology & Therapeutics

Title: Subcutaneous UFH as Anticoagulation Bridge

Keywords: anticoagulation, warfarin, heparin, bridge, DVT (PubMed Search)

Posted: 11/5/2016 by Michelle Hines, PharmD
Click here to contact Michelle Hines, PharmD

Question

Do you have a patient with renal insufficiency who is in need of an anticoagulation bridge to warfarin? Subcutaneous unfractionated heparin (UFH) as an initial dose of 333 Units/kg subcutaneously followed by a fixed dose of 250 Units/kg (actual body weight) every 12 hours may be an alternative to admission for heparin infusion with monitoring.

Answer

Practical Considerations:

  • UFH 20,000 Units/1 ml vial size is available – call the pharmacy to ensure it is in stock.
  • The patient will need a prescription for syringes.
  • To minimize the potential for dosing errors, it may be safest to avoid using subcutaneous UFH for outpatients >80 kg, so that only 1 vial will be used per dose (250 Units/kg x 80 kg = 20,000 Units).
  • The mean weight in a study assessing the safety and efficacy of this regimen was 82 +/- 19 kg. The mean weight in a study pharmacokinetic study comparing the peak antithrombin effect between subcutaneous UFH and low molecular weight heparins was 108 +/- 27.2 kg. 

References

  1. Kearon C, Ginsberg JS, Julian JA, et al. Comparison of fixed-dose weight-adjusted unfractionated heparin and low-molecular-weight heparin for acute treatment of venous thromboembolism. JAMA 2006; 296:935-42. [PMID 16926353]

  2. Morris TA, Jacobson A, Marsh JJ, et al. Pharmacokinetics of UH and LMWH are similar with respect to antithrombin activity. Thromb Res 2005; 115:45-51. [PMID 15567452]

  3. Holbrook A, Schulman S, Witt DM, et al. Evidence-based management of anticoagulant therapy: antithrombotic therapy and prevention of thrombosis, 9th ed: American College of Chest Physicians evidence-based clinical practice guidelines. CHEST 2012; 141(2)(Suppl):e152S-e184S. [PMID 22315259]

Follow me on Twitter @mEDPharmD