Got a call from an intern covering our local Veteran’s Hospital regarding a male inpatient who had thoracentesis performed earlier in the day and now was bleeding into his thoracic cavity. He is on prophylactic enoxaparin and, per on-call Heme/Onc, should be receiving FFP, not protamine sulfate. Trust me, this is more history than we usually get. So this morning at Rounds we scratched our heads and wondered silently to ourselves, Hmm… is anticoagulation secondary to LMWH as reversible with protamine sulfate as is anticoagulation secondary to unfractionated heparin?
It turns out that reversal is achieved with protamine sulfate, but according to Hirsch et al., unlike its efficacy with unfractionated heparin, protamine does not completely abolish the anti-Xa activity of LMW heparins. However, for patients who experience bleeding while receiving LMW heparin, protamine sulfate (1 mg/100 anti-Xa units of LMW heparin) may reduce clinical bleeding, presumably by neutralizing the higher molecular weight fractions of heparin within the product, which are thought to be most responsible for this complication. Smaller doses are needed if the LMW heparin was injected more than 8 hours before the event requiring neutralization. Chest 2008; 133:141S.
It also turns out on-call Heme/Onc did recommend reversal with protamine sulfate (nothin’ but LOVE and RESPECT), but for many likely reasons, that information was relayed incorrectly.
Posted in Clinical Pathology
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Sign in nowI already knew this. I learned this in medical school in our second year. I’m pretty sure it was on the USMLE Step 1. But, I’m glad you learned that today.
Bottom line: never ever trust an on-call intern….Amen!
I can dig it.
Please don’t also forget to restick the patient just in case it is a mechanical issue with the stick.
Excellent point, Doctor.