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Think you know all there is to know about managing warfarin? Think again.

Last Updated: February 5, 2016
Result type: Tools

You know that warfarin has been used for more than 60 years to prevent blood clots. And you know that it works; its effectiveness is well-established. You’re probably also aware that warfarin therapy can be challenging — with diet restrictions, drug interactions, and the need for regular INR monitoring.

So, what’s the best way to manage warfarin therapy: a family doctor’s office, a specialized anticoagulation clinic, or patient self-testing and self-management? If you think you know the answer, you might be in for a surprise.

Based on the best available evidence, it turns out that there isn’t a lot of difference in patient outcomes between different models of care. See the CADTH recommendations for more information.

What matters is having a structured care plan in place.

How often have you “eyeballed” a warfarin dose because you didn’t have a validated nomogram at hand? Have you ever had a patient go for months without an INR test? Has a patient missed vital education because every member of the care team thought someone else would do it? Patients can slip through cracks in the health system, but a structured care plan can help catch them.

Things to consider when developing a structured plan

  • Patient follow-up. When is the next INR due? When is the next office visit?
  • INR monitoring. Who will receive and triage the results? Who will contact the patient? Is this answer different for in-range versus out-of-range INRs?
  • Dose adjustment. If a dose adjustment is needed, which validated tool will be used? Is it electronic or paper-based, and where do we keep it?
  • Patient education. Who is responsible for patient education? How will we ensure ongoing patient education and adherence, as well as caregiver engagement?
  • Monitoring. Who is responsible to monitor for side effects and complications?

Bottom line

  • Optimal management of warfarin is possible in all practice settings. It’s not that difficult, but it needs a bit of attention and a structured care plan.