INR monitoring

[Stephanie Gilbreath]

I am wondering about the experience of other hemodialysis pharmacists in terms of their (if any) involvement with INR monitoring (eg. algorithms, day-to-day workload).  We are expanding our HD pharmacist staffing and am wondering if this is something that we should involve ourselves with.  We would like to improve the current process somehow through pharmacist involvement.  Thanks

[Elena Sze]

Hi Stephanie,

At our site, we have a small number of hemodialysis out-patients that we follow for Warfarin dosing. Thankfully, they all come during the same hemodialysis days, so it helps with workflow. We only dose patients on a referral basis, and these patients must be scheduled for dialysis during the daytime shifts at the hospital (no satellite sites, no evenings/nocturnals) to ensure that we can provide proper follow-ups. When we first started dosing Warfarin, we had a larger number of patients. But as the years went on, some of the patients were able to discontinue Warfarin or switch to a DOAC, so we do have as many patients now.

Elena

[Jaspreet Nijjar]

Hi Stephanie,

At our site, the nurse practitioners mostly monitor the weekly INRs and manage warfarin. The pharmacists are involved with following INR/warfarin by referral mostly for patients with difficult to manage INR and low time in therapeutic range. The pharmacist is then involved in assessing factors that could be contributing to the out of range INR (i.e drug interactions, adherence) and also with helping develop strategies to improve TTR (i.e. written dosing information, warfarin calendars).

A new initiative we are also now involved with is quarterly warfarin report cards for patients on warfarin. These reports highlight the TTR for the past quarter and include indication for warfarin therapy as well as previous TTRs. These are shared with the team on a quarterly basis and it allows for targeting patient’s with low TTRs as well as reassessing the choice of warfarin therapy in some cases.

Jaspreet

[Jennifer Lowry]

In Grand River Hospital in Kitchener we had a pharmacy student trial dosing warfarin for a small number of patients and develop an algorithm a few years ago.  Unfortunately we did not continue the pilot project although it was successful.  I believe it was a significant workload and hard to support on evenings/weekends with our current staffing.

[Derrick Soong]

Hi Stephanie,

Sorry for the late reply … we’ve been dosing warfarin / doing anticoagulation consults since 2010. We not only dose the warfarin, we also manage the intradialytic heparin / LMWH, bridging certain warfarin patients when needed, etc.

I know the BC group has an RN driven algorithm … but I believe it just causes more unnecessary bloodwork that needs to be drawn. If the pharmacist tracks it and asks the appropriate questions / patient history, managing warfarin / anticoagulation isn’t that much work … I personally find it satisfying.

For a population of 260 renal patients (inpatients + outpatients), we have 34 patients on warfarin that we manage. We order INRs weekly (MON or TUES) … and rarely do we order extra INRs (ie new start dialysis, started cotrimoxazole, etc). We do have a suggested dosing algorithm for the evening patients if we don’t get the lab results back before we finish rounds … it’s easy … unless they’re bleeding or have an INR that is 0.5 above the accepted target range, continue on their regular dose that night and we’ll call the patient the following day. Otherwise, hold that night’s dose (ie bleed / supratherapeutic INR). We can order Vitamin K without the MD, but that’s a really rare instance.

Perhaps you can trial it with one HD group and compare with how your current practice is.

– derrick

[Author]

Posts