My last post covered coagulation tests for oral anticoagulants and antiplatelet agents, as well as target levels of reversal. Today, I’ll share more of the Austrian consensus paper on actual reversal of anticoagulants. I’ll also add a little commentary to some of the answers.
This is a lengthy section in the paper, so I’ll split it into antiplatelet agents today, the vitamin K antagonists tomorrow, and the direct oral anticoagulants (DOACs) after that.
Q1. Should desmopressin (DDAVP) be administered to reverse the effect of platelet inhibitors?
Answer: No recommendation. (My answer: no)
DDAVP accelerates platelet adhesion. Very few papers have looked at using DDAVP in patients with platelet inhibition, and those that did had low numbers of subjects. The only positive study showed a reduction in hematoma of only 0.5 cc (in hemorrhagic stroke patients, by the way, not trauma). This is not clinically significant. It is likely that the nonfunctional platelets do not really respond to DDAVP, so this drug is not very useful.
Q2. Should TXA be used in patients receiving platelet inhibitors?
Answer: No recommendation. (My answer: no)
There are few, if any, studies that address this. A CRASH-2 subset with TBI showed no significant difference in intracranial hematoma size after TXA. Only one very small (80 patient) study showed a decreased total hematoma after TXA administration (2cc vs 4cc). I’m not sure how clinically significant this is. CRASH-3 did not address it. Overall there is too little data to make a decision regarding this one. It’s value, if any, is very subtle.
Q3. Should platelet concentrate be administered to reverse the effect of platelet inhibitors?
Answer: No
There are no studies that have shown any clear benefit to giving units of platelets to these patients. And a meta-analysis showed no survival benefit. Giving platelets sounds like a good idea, but remember that the drug that poisoned the patient’s platelets is still circulating. It can and does poison the new platelets as well. So adding more platelets that are destined to stop functioning doesn’t seem like a good idea.
In my next post, I’ll dig into the recommendations for reversing Vitamin K antagonists (warfarin).
Reference: Diagnostic and therapeutic approach in adult patients with traumatic brain injury receiving oral anticoagulant therapy: an Austrian interdisciplinary consensus statement. Crit Care 23:62, 2019.