NCCEd: Neurocritical Care Education for Residents

There's a lot here, so let's go through this systematically. Note that the Deranged Physiology page referenced below gives excellent examples of this systematic process of reviewing ROTEM data. The EMRA page on a simplified approach to TEG and ROTEM also provides a nice algorithm for it. The system for reviewing the results is echoed from both of these sites. The ROTEM graphics were adapted from that page, which in turn were adapted from the official ROTEM documentation. Reference ranges given are from our institution's labs and the results are presented in the same overall appearance that we'd see in our own institutional practice.

First, the clotting times (CT) are all normal based on the reference ranges given, which tells us that the coagulation factors are all functioning well. (Fresh frozen plasma (FFP) and prothrombin complex concentration (PCC) have most of the coagulation factors.) However, the clot formation times (CFT) are higher than normal, which indicates that there's an issue with clot propagation. This could be secondary to thrombocytopenia, poor platelet function, or hypofibrinogenemia.

Next, we can see that the alpha angles are normal. The speed of clot formation/propagation is thus normal.

Finally, we can see that the amplitudes (A10, A20) and mean clot formation (MCF) are all low. This indicates poor clot stability, and could be attributed to thrombocytopenia, poor platelet function, hypofibrinogenemia, or hyperfibrinolysis.

A lot of possibilities here, so we really need to narrow this down. If we look over at FIBTEM, we can see the values (see the normal amplitudes and MCF) are normal. Thus, fibrinogen is not the problem here. That leaves us with thrombocytopenia or poor platelet function.

So, let's look at the patient's platelet count from their CBC. Let's say it's 135k. We've thus narrowed this down to be a problem with poor platelet function. Why would this be? Looking at the patient's medical history, we see that she has a coronary stent that was placed several years ago. She must be on ASA81 monotherapy; review of her medical record confirms this.

If we were to give anything, we'd give a single 5-pack of platelets. However, should we?

We actually have some data to help guide us here. PATCH was an RCT published in 2016 that sought to answer whether platelet transfusion versus standard of care would result in a change in the primary outcome of death or dependence as rated by the modified Rankin score at 3 months for patients taking an antiplatelet within the past 7 days of presenting with a spontaneous supratentorial ICH. This study actually found that patients who did receive the platelet transfusion actually had higher odds or death or dependence. 2022 AHA/ASA guidelines recommend against platelet transfusions for these patients unless they're undergoing emergent surgical intervention; in that case, platelet transfusion might help reduce postoperative bleeding and mortality.