Wednesday, August 14, 2013

Kcentra Administration

After the inclusion of Kcentra to the armamentarium for acute reversal of anticoagulation, a few practical issues have come up that are worth sharing.

1) Product contents:
Depending on the products previously used at a given institution (here it was Profilnine), there are several differences in the contents compared to Kcentra. One particular of note is that Kcentra contains approximately 40 units of heparin for every 500 FIX units.  Therefore a patient could receive anywhere from 200 to 400 units of heparin per dose of Kcentra.  Because of this, there is a risk of exacerbation/reactivation of HIT. In fact, Kcentra is contraindicated in patients with history of HIT (per PI).  Thus, the prospect of actually removing an item from formulary when adding an alternative may not be possible, since keeping Profilnine is necessary for patients with history of HIT. Alternatively, FEIBA contains no heparin, but may have higher relative risk of thrombosis (theoretically).

2) Administration and dilution:
Kcentra is supplied as a lyophilized powder which requires reconstitution with SWFI.   However, no further dilution is recommended. Normally not a problem for small doses (less than 50 mL volume) can be infused via syringe pump. But larger volumes require empty evacuated containers for administration. Conceptually, this may not be an issue, but practically, it is. In a hospital pharmacy, trying to find an evac bag (which are on shortage), or reconstituting the drug at the bedside (where evac bags do not exist), administration issues/delays can occur. There is no information I can find as to why it cannot be diluted further in say, 100mL of NS, but potential studies are in the works.

3) INR recheck:
It seems that the critical INR recheck 15 min after the end of the infusion is simply not being done. Partially as a result of poor education for all parties involved (pharmacy, nursing, PA, physician, lab), and partially because of poor communication at the time of the order to ensure that, "no this isnt a duplicate order, we need another INR 15min after the infusion."

Lastly, the still "unpublished" data comparing Kcentra to FFP which led to the FDA approval is still... unpublished. I am growing more and more concerned as to why, and fearing there is more to the significant 6.1% increase in the incidence of death in the Kcentra arm vs FFP...

More to come on the evolution of the Kcentra, PCC, FEIBA, Novoseven saga.