Thromboelastography (TEG) - APSA Practice Gaps 2019

What says, for intermediate sternal gunshot wound? It is it is a gunshot wound, but it's not it's not about. It's not about gunshot wounds. It's about the gun. It's about coagulation. Right, right. Guns don't kill. It's not blunt trauma, so. So Steve is distancing himself. Okay, uh, this scenario is a 13-year-old male who sustains a transmedia stinal gunshot wound. And in the emergency room, the child's intubated, bilateral chest tubes are placed. And there's some significant hemorrhage occurring. So they've activated the massive transfusion protocol and have decided to go to the operating room because the child is having extanguinating hemorrhage. In the emergency room, they have the ability to do a tag or a thromboelastography, a point of care test to measure clot formation. And on that test, it's been reported to you as a surgeon that the R time is prolonged. The question is, what is the most appropriate next step in the treatment of this patient with this tag result? Platelets, frozen plasma, transic amin transic amic acid, or factor seven. So, tag, this is known as two different, it's it's known by two different terms, tag or rotem. And they are basically the same test. It's just the machine, the way the machine makes the cot is just a little bit different. And it is a point of care test. So in other words, um it can be done well, relatively rapidly without having to actually send it to the laboratory. The machine is, it can be available in the operating room, it can be available in the emergency department. And what it looks at is it looks at the clotting cascade and identifies what might be the best product to use to help with abnormal clot formation. And there was a there was a really nice, there it is. Okay. So this is basically the output that you would get from a tag or rotem. And the thing that's the things that are important are um basically in oh, it doesn't there's not a pointer. But so the the first thing you look at is the R time, and that's actually the time that it takes for the clot to start forming. And that depends upon your coagulation factor. So if your R time is prolonged, you should give fresh row plasma. The next thing that you look at is the K time, and that's actually the time until the clot reaches its it's its fixed strength. And this is dependent upon fibrinogen. So if your K time is abnormal, then you should administer cryo because that's where most of the fibrinogen is is available. The alpha angle is actually the speed of fibrin accumulation and it's it's related to the kinetics of the clot and again it's it's it's dependent upon fibrinogen, so cryo precipitate can be used to uh help with those issues. The the the alpha angle or the the maximum amplitude is the highest vertical amplitude of your tag, which is the maximum strength of your clot, and that depends upon your platelets. And not only the number of platelets, but platelet function. So if you have an adequate number of platelets, you may want to consider giving DDAVP to help with platelet function or transfuse platelets as needed. And then your your your L30 is actually the the time the 30-minute clot lysis. So in other words, the the percentage of clot lysis 30 minutes after your maximum amplitude and that is related to excess fibrinolysis. So if you have issues with that, you should um you should provide the patient with transx transxamic acid or um aminocaproic acid. Um, there are a lot of uh institutions that are trying to institute the use of tag in the trauma situation. It has been commonly, fairly commonly used in cardiac surgery and um liver transplant surgery. And I'm interested to see how many people are trying to use this at their institution for trauma. So everyone has written no that they've never heard of tag in so far. No one has written yes yet. Um, so I just like to What about what are we doing? What about the audience here? We do. We use tag um as part of our work up for trauma and we use it obviously in the operating room for for patients who have significant coagulopathy or in the Q, but yes, we do use it as part of our. Um and we and I think it does help you be much more directed rather than, you know, you guys were talking earlier about sort of one to one kind of transfusion and it allows you to be a little bit more precise about how how you're responding to what you're seeing in front of you. Um, do you think in this case, you know, tranexamic acid was obviously one of the options, would you give both? I mean, we talk about tranexamic acid, the crash 2 study and stuff like that as a as something that's indicated in trauma patients with significant hemorrhage. Would you give both or would you just start with with FFP and see how? I would start with FFP. So how were you able to implement or get tag implemented into your. We have it at our institution with with transplant, but we have not been able to adapt it for trauma or uh other aspects. Yeah, so I I and I'm going to hedge a little bit here because I'm not entirely sure whether we actually have the ability to do rapid tag in the in the bay, but we can send tags um to the lab and get them back. We use them for ECMO obviously as part of our ECMO program and and we've integrated it because of also the cardiac ORs and and the fact that they use it from perfusion. But all of our ECMO patients get a tag, you know, at least once a day if not twice a day if they're having coagulopathy issues. So, uh I need this dumbed down for me a little bit. So uh let's go through this again. So you get the tag, you order tag, the tag test, it comes back and how do you get like what does the result look like? And do you have to have this table in front of you to? So the result looks like that diagram down there. So how does? Well, it depends upon your laboratory. Some laboratories will provide you with, they'll say your R time is prolonged, suggest FFP administration. They'll give you the suggestion. Yes, it depends upon your lab. We're not that fancy. If not, you need to have, you need to have a table like do you just know off the top of your head or do you have to look it up in the table? It's somewhat it depends on how frequently I've been using it when we've had a bunch of kids on ECMO, it sticks more and then but a lot of times I do have to go back to it and reremind myself, okay, wait, this is that. But as you use it more, it it it seems very complicated when you look at it initially and trying to remember each of the pieces, but I think as you use it more, it becomes. It makes sense to me that this would be a simple thing to implement to have a result that comes back like that recommended uh would be blah, blah, blah and probably eliminate some error of interpretation. Um, so this was and it comes back within an hour usually or. Well, it it depends upon if you have rapid tag or not. Um it can take up to three hours to come back if it's not a rapid tag. Um rapid tag is about less than an hour, 30 minutes to an hour. Okay. All right. It also depends on your institution and whether or not if the machine's warmed up, how often you're using it because I know that was something for us at my institution when we first started incorporating it. Um, we just didn't use it very often. So we had to call the lab and tell them, like, hey, we're going to run a tag. Can you warm it up? But when it is live, uh if you have the capacity to watch the results as they're coming in, you can get three of those four like key pieces of information within 10 minutes because really the only thing you're waiting for the full half hour on is the 30. Is your 30. So you can kind of respond in real time. Um, and there's a great resource on uh we can put it up. if you Google uh for like life in the fast lane tag, they have a great breakdown for analyzing uh these diagrams that you see here and then a nice nice little mnemonic based on like whether it looks more like a wine glass or like a a a tumbler, um, for how you should be responding. So, and then finally, we just recorded a podcast on this topic with Dr. Adam Vogel from Texas Children, so that's going to be something that'll be coming out in the next uh couple months for people to have on their horizon. Um, explain to me the trans transic acid or how do you even pronounce it? Transic acid. Transic acid. Talk to me about that. When I don't know when do you use that. Yeah, so there, I mean, I don't know, I'm probably not the most up to date on on answering this question, but there the crash 2 study looked to study transic acid in adults particularly and in in life threatening hemorrhage after trauma and demonstrated that it it had a significant benefit. Um, and so the major counter indication to it is head injury. And so you you can't use it in kids with in kids or adults with significant head. And this is also this is TXA. This is TXA, which is how people like me pronounce it. Yeah. Okay. Um, and this is and this is also was uh greatly discussed by Notrica about the use of TXA in trauma. Um, in uh one of the previous uh courses. All right. Comments, questions? I think that physiologically, this really makes a lot of sense to use, but it it's been out for a while now and it hasn't really caught on as much as you would think something would in this nature, even for ECMO. I mean there's still we still follow the activated clotting time. It's just much easier, much quicker and and has the same random pattern that a tag probably would have to in the situation. So I don't know. Why is tag not just become the standard of care at this point? Well, that's why we need courses like this. It it it is amazing how this type of dissemination and and the point that Apsa makes that doing it at everyone's conference. You know, if the same topic is presented over and over again at multiple different conferences, you will see what we saw with Gipps, that it was an overnight trend. just a a little point. The the it used to be that when the first Nissen was done, the first laparoscopic Nissen, it was 10 years until it was adopted. Our adoption rate has gone down to about a less than a year now because of digital, because we can now disseminate things much faster. You can get other people's input and opinions on things that are usually what is necessary to get it to be put into practice. They might read about it but not implement it. Now things are happening much more rapidly. So I think that within a year or two instead of 10 years, we're going to see this being implemented more. I think that the question that I think Dr. was pointing to is also just utilization and how we, you know, that one of the advantages to ACTs over the tag is how rapidly you can get them back. So you're standing at the bedside and you're having a hard time figuring out what to do with your ECMO patient who's having circuit issues or whatever, you get that information much more quickly. Whereas there there is a delay to tag. I think the rapid tag helps a little bit with that delay because you can get that at least especially the initial information more quickly, but you have to A know how to use it and and be have the infrastructure to be able to get it as quickly as possible. So that does create some obstacles I think to implementation and probably. Perfect. I think she just hit the primary issue is infrastructure. Yeah, good point. Yep. Okay. Uh,