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Cardiac Labs – What and When to Use Them

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***Previously Recorded***

Do you need a troponin or a CK-MB? What about a CK-MM? BNP?! In this session, we will cover all those pesky labs that deal with your cardiac patients and what they ACTUALLY mean.

Video Transcript

Alright. Can you guys hear me now? Yeah. Alright. Is that better? Cool. Yeah. Sorry. Sometimes it’s really picky with the feed sometimes. All right. Yeah, let’s do this. Let me get back to the screen, the screen share screen. Okay, cool. Yeah, no worries. All right, so, um, you don’t on screen. Okay, great. Cool. So in the instance of, uh, this, this demand going up and the heart or the cardiovascular system for whatever reason, it causes us decrease in oh two. So there’s an increased demand for OTU but the body can’t keep up. So it causes necrosis. Now I want to show you guys something else. Um, so you have cardiogenic, uh, they’re there. Let me back up. There were two reasons why you would have a, the main dischemia and the first one is going to be, oh no, there we go. Um, and the first one is going to be cool.
Uh, the first one is going to be this cardiogenic, uh, acute coronary syndrome. That’s going to be, hey, there is maybe some atherosclerosis. Um, there’s some sort of blockages that kind of stuff. Um, unstable angina. That would be, that would cause the main aschemia without the heart attack. Um, just because there’s no, uh, um, Brian’s has heart failure and not necessarily, um, more, it has to do with lower profusion. I’m gonna show you guys something really cool in a second. Then there’s obviously non cardiogenic. Um, so let’s say you have somebody that has, uh, let’s say their kidneys aren’t functioning right, so you have changes in the Renin angiotensin system, right? So that gets messed up. So then you get this hypertension, you get this squeezing down in the clamping of those heart vessels and now you have decreased. You can end up getting decreased profusion.
That’ll cause the other one is sepsis. The sepsis ends up being shock and that shock equals decreased, uh, decreased perfusion. And guess what? Decreased perfusion equals and increase in tropes. So just because a patient, like if you do cardiac levels and you get a hydroponic, and you have to understand that it’s not specific, it doesn’t, that’s not the indication that there’s a heart attack. You have to do more than just that. They’ll have questions. The president phone is not the hallmark lab because it can be elevated. Not necessarily so Eliana. Oh, okay. Yeah. So you have to, the thing you’ll always hear me talk about is that I drive this point home all the time is you can’t just, um, pay attention to numbers. Like, just because a truck comes back doesn’t mean that it’s a heart attack. Is my patient complaining of chest pain or are they complaining of any sort of chest pain or they’re complaining of nausea, vomiting? What is your EKG showed this? Do they have segment elevation? Have they uh, had, um, a cath had they have, they had a previous stent where their Litho does look like there’s a lot of other values that go into it. So one value doesn’t mean one thing. So let me show you guys something really cool. Uh, I show you around here. I gotta put it up there. How many of you have actually been inside the academy to look at this bio digital?
dude, if you haven’t, go do it. So cool. I love this stuff. All right, so this is actually inside the academy. You can go into the library if you’re in an unlimited user, if you’re chatting, I know you can. Um, cause that means you’re on limited. So if you go in here, you can actually click and do all this stuff. So what I’m actually going to show you, check this out. So I’m going to zoom it in. Okay. If you look, let me see if I can click off of it. Okay. You can see like right here, it’s a nice and bread, kind of like pink and looking healthy. But as you, I’m struggling to take this up. Oh my goodness. Do this with a different house. You can see how all of this tissue down here is actually dark and looks in a chronic. So let’s zoom in a little bit. We’re gonna zoom in, Zoom. Use any,
Oh, too far. Too Far. Cool. You can look and see right here. Guess what? There’s my atherosclerosis because my patient has coronary artery disease and all of a sudden part of it breaks off a clot forms. The blood is supposed to be going down. This, uh, um, down. This pathway right here is not going. And now I’ve got an issue here. Now I’ve got this clot and now my patients, um, now my patients, uh, tissue is all is all done. So that’s what I wanted to show you guys there because that’s really interesting and it kind of drives from that point. I will why those, um, those cardiac myocytes die because you’ll get that. Um, you’ll get that, um, decreased perfusion. So let’s go onto another one for English purpose. What do you consider as the lab related presence of an MMI, if not for pony? Well, let’s take a look. Okay, hold on. Let me make sure what’s your mind.
we’ll go through it. We’ll come back to BMP. They actual value is, um, so CJ kratom kindness. Creating kinase is a value that has to do with the breakdown of muscle. So if we look, there are actually three that we paid attention to and these are actually called [inaudible]. Thank you. I still enzymes.
So there’s damage to the muscle and you have these three variants. You have c, k, m, m, which is skeletal muscle. So this would be associated with maybe some sort of trauma. Then you have CKMV, which is cardiac muscle, and then you have CK bebe, which is actually, um, it’s an enzyme secreted in the brain when there’s trauma to the brain or maybe some sort of inflammatory process and the cells die. Uh, that’s where that’s going to happen. The one we want to look at as this guy is c k m B. So let’s go to, it’s a CK-MB normal values 2.4 and integrates for Mil. So it’s less than that. So it’s really low. The thing about CK-MB is it’s detectable three to six hours. It peaks in 12 to 24 in the c k n you can use the CK-MB instead of the truck. So if for whatever reason you don’t have that capability, you can, that’s going to be the one you want. So the way I remember it is c k m m is for muscle. So you want to look, um, so let me go back. The amz mean muscle.
Two B’s meaning brain and what’s left is cardiac.
So yeah, some people will do this UK MB. When it’s combined with proponent, a troponin typically will peak a lot sooner than an a. Then the CJ envy. Well, so let’s see, I’ve got some questions in here. So in lieu of that you can actually do it. So yeah, the, it’s detectable and three to six hours. I’d have to look up a specific lab. I’d have to look it up, but it’s, it’s gonna depend on facility, but it’s usually like one to two hours is it? But troponins aren’t like the gold standard for um, detecting an MRI. So let’s go back. We’re going back for a second. We’re going to go back to the other cardiac lab. We want to talk about his BNP. She is brain nature etic on it. Peptide. This is a protein found and there’s three of them. There’s a and P, B and P and CNP. The one we were want is the B and p and it doesn’t make sense B, but the longer one is this one BNP. So inside the heart, okay, here’s a picture of the heart. So as you’re probably one of the best parts I’ve ever drawn. All right. So ventricle here, let me change.
we change my color real quick so I can show you ventricle, ventricle, Atria, Atria, right? So what you’re looking for is as these, as you get more pressure inside,
The, um, the ventricles, they stretch. Okay? So there’s more, there’s more pressure and they push outward. And when you get that stretch, you actually get an increase in BNP secretion from these overstretched ventricles. What happens is the, the heart assumes that because there’s too much pressure in here, that there’s too much volume. So this increase in volume triggers this B and p release. I think it’s actually on the next slide. I wrote this up. I don’t want to just draw it right now. You get this BMP release. This BMP release ends up turning, um, turns on the kidneys and says, hey, we need to increase urine output. And because we get urine output, we get a decreased intra vascular volume. That means that the volume inside the bar, the cardiovascular system decreases. Therefore, this increased volume and pressure decreases. Therefore the stretch is reduced and the heart isn’t overworked. Do I need to do that again? Okay. Does everybody, does everybody have their writing utensils? Alright, everybody’s ready? Yeah, it’s uh, it is a, hold on Brian. Let me tell you, the parts of it are a positive feedback loop and parts of our, a negative feedback loop.
For the most part it’s a negative feedback loop because we want to turn it off because it’s positive to a degree. But overall it’s a negative. I wouldn’t worry so much about positive versus negative feedback loop. What I wouldn’t focus more on is what’s going on. Alright, so increased volume in the ventricles means increased stretch. That’s telling the heart that there is too much volume and that equals too much work.
Okay, so what happens? The P is excreta and BMP tells the kidneys increase urine output because we want to get rid of intravascular volume. We want to reduce the workload on the heart, increase urine output production. So it promotes diarrhesis, which is nature uses. And what happens essentially is in a, that’s the sodium. So it tells to kick out sodium and the waterfall is the sodium. That’s what natural means. So this increase in urine output means that you have a decreased intra vascular volume. That’s an everything’s working right. Obviously this doesn’t work all the time. And I’ll explain them about heart failure. A second ancient of vascular volume and decreased intravascular volume. That means old decreased workload on the heart.
Uh, it’s going to be days, it’s, it literally is days. So Brian has, does this happen in minutes or hours? It’s never going to happen in minutes. I mean, even if you gave like one of the most powerful diuretics, lasix, it’s not going to happen. So imagine this, imagine you have this constant pressure, pressure, pressure, pressure, pressure, pressure, pressure, pressure, pressure, pressure, pressure. Remember the heart is a pump. So the pump weakens over time. So even if we’re able, even if the increase in BMP is still staying up and the kidneys are still trying to diaries, well guess what the heart is that the pump is broken now. So now you get this increase in this BMP and it starts to go into the blood. So imagine. So what they do is that actually categorize a BMP or um, heart failure based on the BNP levels. So a hundred to 300 is mild heart failure greater than 300 is moderate and then greater than 900 is severe.
So basically this heart is not working and can’t, even if it does want to to kick out a BMP to the kidneys, it’s not going to be able to efficiently because it just can’t call. So that’s how a part failure plays into it. Actually. Basically what we wrote is just here, right? It would be painted digital is increased volume plus plus a weakened heart that makes that BMP go up. Now an increased VMP does not equal heart failure. You need a combination of these things. You need, you need to check on an ed tray and you’re looking for Cardio Omega Lane and you also need an echo. You need to look at something called a fractional shortening or
um, e f which is ejection fraction. This is the one that really concerned about ETF is not only 50 to 60%. So basically the, when the heart pumps, it’s pumping out 50 to 60% of, um, I’m sorry, it’s pumping out. Uh, it’s leaving in 50 to 60% of the blood. Now what’s happening is, uh, patients that have congestive heart failure have decreased ies of like 20. So basically it’s only 20% efficient. So those are the ones that are gonna look at. All right, let’s go through some questions. I’m jumping around and today we go wide arrives in the emergency department complaining of chest pain that began four hours ago at chipotle. I, let’s ask, some specimen is obtained and the indicate
a level of 0.6 nanograms per mil. The nurse determines that this result indicates which finding you guys tell me which one it is. Three, three, three, three, three. Yeah. Threes, threes, threes. It’s pretty, I love, actually I’d been, I’d be jumping. Um, so a normal level, no, cause remember we want to be less than 0.03. Um, so some people say 0.1, some p, some facilities, state 0.01. Um, a low value. It’s not low. It’s high. So we know it’s not that one. Um, a level that indicates the presence of Angina. Angina is a symptom. Um, not necessarily a disease process. We’re worried about what’s going to be the most indicative of what’s going on. So we get that. Sharon and I, we are dealing with,
that’s correct. You guys are all right. So this is all a high trust level. All right, next one. That was pretty, pretty straight forward. Alright, cool. Client arrives in the emergency department complaining of difficulty breathing. BMP, blood specimen is obtained and results indicate a level of 4,200 picograms per mil. The nurse determines that this result indicates which finding level normal level severe heart failure or mild heart failure.
so mild heart failure is from what range?
okay, so what it is.
Moderate is
Wow, Liz, great. On the 300, what is severe, right? Or the 900. What does our patients B and p level 4,200.
So is this mild, moderate or severe? This is severe, severe heart failure. I think that’s the highest I ever saw was like 4,200. This guy would be on the list for a new heart? Pretty much. So yeah. These are, these are in click style questions in the sense that they’re similarly at least set up. I’m not necessarily sure that, uh, that you would see exactly these style of questions or these like set up this way. What I’m wanting you to do here at this point is recognize what’s normal, what’s indicated by these cause I think they’ll help you more in a clinical setting. All right. All right. A client arrives in the emergency room with a suspicion, heart attack, complaining of chest pain and nausea that provide our staff or as a stack trope, the lab reports that analyze it for the deponent machine is not functioning. Which of the following tests would the nurse then suggest to confirm the diagnosis of a myocardial infarct? It says, or if CK-MB or key says too. All right, so number one, creating kinase. We use that to look at damage to overall skeleton muscle. So it’s not that one B and p is the test we would use for congestive heart failure. C K M M is an ISO enzyme that tests what type of muscle. Mm. Number three, right? The skeletal Muscle
C K M B is four.
MB not being not beebee. Beebee is for brain. So CK MB cardiac possible. Right. So number four is the one that you can do in lieu of entrepreneur.
That’s it guys. Good job. Yeah. The thing, the thing I really wanted to drive home with those is that a, is that I want you to know the difference and saying, Hey, look, I’ve got a patient that’s got, um, I’ve got a patient that is, uh, maybe they’re have some chest pain. Is that BMP really gonna help me for my chest pain patient, not likely you need tropes and C can be, I’ve got a patient that has some mild elevations of your opponent, but they’re also in renal failure. Well, maybe demand ischemia because all the other patients symptoms are fine. Like, I want you to start to process and learn these a little bit more, but there’s a longer time period. Yeah. So it’s going to take a little bit longer, um, too, uh, for that, that CK-MB to rise. But think about it like this from the time of actually onset, um, to the time he’s actually into the door in the door to the time you get the value until the time he goes to the lab and the time you get it back, what do you, it’s gonna be a few hours so you can actually set it elevates in three to six hours.
You’ll see an elevation in three to six hours for, for a, um, for STK MV, they stay elevated for 12 and 12 to 24, something like that. Um, your trip, troponins are going to elevate faster, but they’re going to stay in the system longer. They gonna you’re gonna start to see an increase, um, you’re gonna start seeing increased sooner. They will peak later and stay longer, if that makes sense. So the value looks like this virtual opponent, it starts to go up and then it starts to go up and up and up and up and up. And that’ll stay that way. But that’s why down here, where’s my finger. And that’s why the sensitivity level is so much lower because the normal value should be basically nil. So any sort of elevation, a company plus all their symptoms totally puts them in a qualification. For some, I was talking to a heart attack 24 to 48 hours presented er. Um, but it stopped. I wouldn’t be, I wouldn’t be concerned if a patient is having a heart attack for 24 to 48 hours
or is it where she or he or if it was a female patient, they didn’t have normal symptoms. You’ll see those tropes go up, the tropes will go up. The biggest thing is determining if their chest pain is significant enough to do anything about. So for instance, my phone on long had a heart attack in our house. Um, not fun by the way, cause I was like, uh, last year nursing school and I thought I was everything and that was a very humbling experience because I couldn’t figure it out. I was like, oh, I don’t know. Um, but uh, he didn’t present a typical way either. He had been just nauseated all day and he’d had just a touch, just a little bit of like the dull ache, chest pain, nothing radiating, nothing crushing. And they were like, you need to go. So, all right guys, my time is up.
I’m willing to check out here for today. Um, we’ve got some more sessions yet. Yet he went to the Er. He was in ICU for, um, I guess I didn’t finish the story, please. They, er, they tried to send them, they couldn’t send him. He was in the ICU for three days. Then there’s a triple bypass on him, and he stayed with us for a month. So I got to live with my father a lot for him. It was nuts. I gave you one hell of a time. All right guys, uh, you guys go out and have a kickass rest of your day. Um, and as we always say, happy nursing.