Arterial Pressure Tracing in Critical Care

Many of our patients will have an arterial line at some point during their stay in the ICU. The values that we get will help to guide a lot of different therapies and treatments that we can offer. But there is more to an arterial line than just the numbers. In this lesson, we're going to talk about what it is that you're actually seeing with the arterial pressure tracing. All right, you guys, this is Eddie Watson, and welcome back to another video lesson from ICU Advantage, where my goal is to give you guys the confidence to succeed in the ICU by making these complex critical care topics easy to understand. I truly hope that I'm able to do just that, and if I am, I do invite you to subscribe to the channel down below. When you do, though, make sure you hit that bell and select all notifications, that way you never miss out when I release a new lesson. Now, to test your knowledge at the end of this lesson, head over to icuadvantage.com or follow the link down in the lesson description and check your learning while also being entered into a weekly gift card drawing. And also don't forget that the notes for this lesson as well as all of the others are available to the YouTube and Patreon members along with some other great benefits. You can find links to both of those in the lesson description down below. So with all that out of the way, let's go ahead and get started here. In the last lesson, I talked about the basics of an arterial line. including the reasons that we use them. I briefly talked about the monitor that our A-line is hooked up to. Now this monitor is where we get our values for our pressures, but along with those numbers, we also see a visualization of these pressures. This is what we call the arterial pressure tracing. It's important to understand what's going on with this pressure tracing, along with some of the things that it can tell us, especially in regards to the accuracy of our line. So let's start off talking about the basics of our pressure tracing. So here is an example of a basic arterial pressure tracing. There are a few parts of this that I do want you guys to know. First is going to be the large rapid upward tracing. This is what we call the systolic upstroke. So this is formed by the rapid increase in arterial blood pressure as the heart is ejecting blood. Where the waveform begins its rise is where the aortic valve actually opens and marks the beginning of systole. Now next along here we have the peak of this wave. And this is the peak systolic. pressure. This is what's going to register as our patient's systolic blood pressure, or SBP. Essentially, this is the highest pressure at the strongest point of contraction of the left ventricle. Now, following the peak systolic pressure, we have the waveform moving downward, and this is actually called the systolic decline. Important to know, though, is that the heart is still in systole here. The heart is still contracting, but the left ventricle has ejected most of the blood it will eject, and this is the remaining bit of contraction which is not as strong. hence the decrease in pressure. But it is still a much higher pressure than the baseline. So then the next part of the waveform is going to be this slight upward wave before continuing further downward. And this is what we call the dichrotic notch. The significance of the dichrotic notch is this is when the aortic valve closes. As the valve closes, we see the pressure in the aorta bounce back off the aortic valve, giving us this slight upward movement in pressure. The dichrotic notch also signifies the end of systole. As I mentioned, we have systole that starts here at the upstroke and ends here at the dichroic notch. This whole area underneath the pressure wave is all systole. Now after the dichroic notch, we see a decline in pressure. And this is what we call the diastolic runoff. This is the pressure in the arteries equalizing back down after the increase from systole. So this continues until we reach the lowest point just before the aortic valve opens. and we begin again. From the dichrotic notch to the start of the systolic upstroke, this is all diastole. The lowest point that we have here is our minimum diastolic pressure, and is what's going to be registered as our patient's diastolic blood pressure, or DBP. Now, knowing all of these parts, we can actually get a little more information from the waveform. Now, the difference between the peak systolic pressure and the minimum diastolic pressure, this is what we refer to as our pulse pressure. Now, if we take the sum of all of this area under this waveform, this gives us an indication of our patient's mean arterial pressure or their MAP. Now, from here, even more information can be attained with analysis from more advanced monitors. While this is going to be beyond the scope of this series, it is useful to understand the basic principles here. So here, if we look at the slope of this systolic upstroke, which is how quick the upstroke is going, this is actually correlated to contractility. The area under the systolic curve is a representation of our patient's stroke volume. This can then be multiplied by the heart rate to determine cardiac output. Then we have the slope of our diastolic runoff is going to be correlated with vascular resistance. So that gives us a good breakdown of the different components of the arterial pressure tracing and what each of those mean. The last thing that I do want to discuss with this pressure tracing here is going to be the alignment with our patient's ECG. So here is actually a corresponding ECG tracing aligned with this pressure tracing. The thing that really stands out here is that the QRS complex occurs before the systolic upstroke. As a result, the arterial pressure tracing will trail behind the ECG tracing. The reason for this is that the ECG is measuring the electrical impulse. The electrical activity takes place followed then by corresponding muscle contraction in the heart. There's approximately 180 millisecond delay from the R wave of our QRS complex to the start of the systolic upstroke. All right, so now that we have an understanding of what the arterial pressure tracing is, I want to talk about something that I talked about in the last lesson, but I did want to cover in a little bit more detail here, and that's going to be distal pulse amplification. Now, as mentioned in that previous lesson, the more distal our pressure reading is, the higher the peak systolic pressure that we see. So again, this is due to the reflection of the pressure wave against those smaller vessels further down the line. And what happens is we see an augmentation of the arterial pressure tracing. That reflective wave is going to augment or increase that systolic blood pressure. So this is shown with the following tracings. So here we're looking at a tracing from the aorta, the brachial, radial, femoral, and dorsalis pedis. As you can see, the further from the heart we go, the greater the peak systolic pressure and the less defined the dichrotic notch. So to really help to understand this, you need to know that there are actually two pressure waves that are at work here. So we have the pressure wave of the forward flow of blood, best represented by the aortic pressure wave. So this is as the heart contracts, that pressure wave that's created and is going to travel out and about through this system. Then we have another wave, which is going to be the rebound pressure wave. Again, the further out we go, the stronger this becomes. These two pressure waves actually get added together and are represented as the arterial pressure tracing that we see, which, as I showed you, will vary depending on where we have our arterial line. All right, now that we understand about our normal pressure tracing, we need to discuss situations where we would see abnormal pressure tracings. The first of these we can talk about. together and they have to do with something that we call damping. Damping is essentially the influence of reducing our pressure tracing. Now the simplest way that we can think about this is like the loss of energy from a bouncing ball. As a ball is bounced, it loses energy each time and each successive bounce is smaller. This is essentially damping of the bounce of the ball. Now this is essentially the same concept, but this is now going to be damping our pressure wave. And so I will be talking about this more in the next lesson, but we do use a short, very stiff tubing from the arterial catheter to the pressure transducer to actually record our patient's blood pressure waves. This stiff tubing helps to reduce the loss of energy or that damping of that pressure wave as it travels along the tubing. The length of the tubing can also play a role in this damping as the longer the tubing, the more the damping that we see. So sometimes we can have an influence on the system that can either increase how much damping can take place, causing a reduction in the energy of the wave, or it can actually work the other way, adding energy to this wave. And so the first situation with damping that I do want to talk about is something that we call over-damped. And this is when there is more damping or more loss of energy than is to be expected. So when this occurs in our arterial line setup, we're actually going to see decreased heights of our waveform, meaning a falsely lowered systolic blood pressure. Now, oftentimes we're also going to see an increase in our diastolic blood pressure, giving us a narrower pulse pressure. Now there can be a multitude of reasons for this happening, which I am going to discuss in a future lesson looking at troubleshooting. The end result though is a systolic blood pressure and possibly a diastolic blood pressure that are not true. This could of course lead to improper clinical decision making. Fortunately again, one advantage of the arterial line is that the MAP is generally not going to be impacted, and one of the reasons that we primarily use this in critical care. Now the other damping situation is going to be something that we call underdamped. So sometimes the opposite exists where we actually see more energy added to the waveform giving us less damping. Now this can seem a little counterintuitive, but I heard a great analogy to remember the difference between overdamped and underdamped. And this analogy uses your hair. If it's wet or damp, then it's going to lie flat. In the case of our A-line, an overdamped pressure will be a flatter pressure. Hopefully that'll help you guys to be able to distinguish between over and underdamped, and what you would expect to see with your waveform. So the result of underdamping is that we're going to see falsely high systolic blood pressure, and falsely... lower diastolic blood pressure. The added energy causes the waveform to oscillate more, which is why we see this happen. So this is going to give us a larger pulse pressure. Again, there can be several causes of this, which I will discuss in the next lesson. And again, this can lead to improper clinical decision. But once again, fortunately, the map will generally remain accurate. All right, so that was kind of a lot to unpack with damping. It's definitely not something that we normally think about in terms of critical... care and the things that we're doing for our patients, but it definitely will have an effect on our A-line and its accuracy. And so that actually leads right into something that I want to talk about that's called the square wave test. So now that we know our pressure tracing can be inaccurate due to damping, what we are needing is what we refer to as a optimally damping of our waveform. Knowing this waveform is accurate is imperative as some of the treatment options will depend on the accuracy of these numbers. Fortunately, we have a very easy test that we can do in order to check the dampening of our system, and this is called the square wave test. Now, you may also hear it referred to as the fast flush or the dynamic response test, but they are all the same thing. So the way to do the test is by activating the flush from the transducer. When we do this, the flush rate is drastically increased and causes our waveform to quickly jump up and off of the screen. After just a second, we release the flush, and what we expect to see is an almost as quick drop back down. and this creates what appears to be the top of a square, hence the name square wave test. Now when the wave form comes back down, it will overshoot our baseline. The normal pressure on the system, aka our patient's blood pressure, is going to push back trying to level back out to its baseline. This leads to an overshooting above the baseline, and just like the bouncing ball, we see this oscillation until we reach the baseline. Now we expect to see one to two oscillations when we do this test. If we see this, then this we consider to be be optimally damped. Now for the cases of over damping. If our system has too much damping or over damped, we would expect a flatter wave in our tracing. This also has an effect on the square wave test. The upstroke is not going to be as quick, nor will the downstroke be when it's released. There will be no oscillation when returning to the baseline, and in fact this return to baseline might even be slow and exaggerated. So when this happens, you are going to need to troubleshoot the arterial line and repeat this test. So if our system has too little damping or underdamped, we'd expect an exaggerated waveform. Once again, this has an effect on our square wave test. The upstroke and downstroke are going to be quick as we expect them, but we are going to see additional oscillations while it's trying to return to baseline. Again, think that we have too much energy, so imagine the bouncing ball analogy. The ball will be bouncing more than expected until that energy is lost. So if we have more than two oscillations, then this is an indication that we have underdamping. And once again, we're going to need to troubleshoot that arterial line and then repeat this test. All right, so I know the concept of overdamping and underdamping can get a little confusing, especially when you're trying to remember what one's flatter and what one's larger. And so I did want to put up just a couple examples for you guys here. All right, so this is going to be an example square wave test. So if you perform this test on your patient and this was the square wave test that you got, what would you consider this to be? Hopefully you looked at this and you saw a quick upstroke, a quick downstroke, and just a couple oscillations here. And so this tells us that we actually have an optimally damped arterial line. And what does this mean for our patient and our A-line? This means that our arterial line is going to be giving us accurate numbers. All right, so again, let's put up another example of another square wave test here. So if you saw this result when you perform the square wave test, what would this be? Well, hopefully, again, you saw that quick upstroke and quick downstroke, but you saw an exaggerated number of oscillations at the end, and this would be an indication of underdamped. Now, knowing this information, what would you expect to see with your patient's arterial blood pressure tracing? Hopefully, this would tell you that you would see too much energy in the system, thus an exaggerated waveform, giving us that higher systolic and lower diastolic blood pressure. Alright, one last example here. So here again we do a square wave test and this is what you get. What would this be? Well here hopefully you saw that slower upstroke and that long exaggerated downstroke with no oscillation at the end. This would be an indication of over-damped. Knowing this, what would you expect to see for your patient's arterial blood pressure tracing? Well, hopefully this should tell you that there is a loss of energy in the system. Therefore, you are going to see a flatter waveform, giving us a lower systolic and possibly a higher diastolic blood pressure. All right, so hopefully some of these examples help to cement some of this information in there. And then hopefully this lesson was a good review of what it is that we're actually seeing with that arterial pressure tracing. It helps to have an understanding of what's happening at these different points and what that tracing actually tells us. So. I really hope that you guys enjoyed this lesson. If you did, please go down below and leave this lesson a like, as well as leave me a comment. I love reading your comments and trying to respond to just about everybody there. Also, make sure you subscribe to this channel if you haven't done so already. Special shout out to the awesome YouTube and Patreon members out there. The support that you guys are willing to show me and this channel is truly valued and appreciated, and so a big thank you to you guys. For the rest of you guys, if you'd be interested in showing support for this channel, you can join the YouTube membership down below. or head over to the Patreon page and check out some of the additional perks that you guys get for doing just that. You can also support this channel by following some of the links down in the lesson description, as well as checking out some of the awesome t-shirt designs I have down there as well. Make sure you stay tuned for the next lesson in this series, otherwise check out a couple awesome lessons I'm going to link to right here. As always, thank you guys so much for watching, and have a great day.

I truly hope that I'm able to do just that, and if I am, I do invite you to subscribe to the channel down below. When you do, though, make sure you hit that bell and select all notifications, that way you never miss out when I release a new lesson. Now, to test your knowledge at the end of this lesson, head over to icuadvantage.com or follow the link down in the lesson description and check your learning while also being entered into a weekly gift card drawing. And also don't forget that the notes for this lesson as well as all of the others are available to the YouTube and Patreon members along with some other great benefits. You can find links to both of those in the lesson description down below.

So with all that out of the way, let's go ahead and get started here. In the last lesson, I talked about the basics of an arterial line. including the reasons that we use them.

I briefly talked about the monitor that our A-line is hooked up to. Now this monitor is where we get our values for our pressures, but along with those numbers, we also see a visualization of these pressures. This is what we call the arterial pressure tracing. It's important to understand what's going on with this pressure tracing, along with some of the things that it can tell us, especially in regards to the accuracy of our line. So let's start off talking about the basics of our pressure tracing.

So here is an example of a basic arterial pressure tracing. There are a few parts of this that I do want you guys to know. First is going to be the large rapid upward tracing.

This is what we call the systolic upstroke. So this is formed by the rapid increase in arterial blood pressure as the heart is ejecting blood. Where the waveform begins its rise is where the aortic valve actually opens and marks the beginning of systole.

Now next along here we have the peak of this wave. And this is the peak systolic. pressure. This is what's going to register as our patient's systolic blood pressure, or SBP.

Essentially, this is the highest pressure at the strongest point of contraction of the left ventricle. Now, following the peak systolic pressure, we have the waveform moving downward, and this is actually called the systolic decline. Important to know, though, is that the heart is still in systole here.

The heart is still contracting, but the left ventricle has ejected most of the blood it will eject, and this is the remaining bit of contraction which is not as strong. hence the decrease in pressure. But it is still a much higher pressure than the baseline. So then the next part of the waveform is going to be this slight upward wave before continuing further downward. And this is what we call the dichrotic notch.

The significance of the dichrotic notch is this is when the aortic valve closes. As the valve closes, we see the pressure in the aorta bounce back off the aortic valve, giving us this slight upward movement in pressure. The dichrotic notch also signifies the end of systole. As I mentioned, we have systole that starts here at the upstroke and ends here at the dichroic notch. This whole area underneath the pressure wave is all systole.

Now after the dichroic notch, we see a decline in pressure. And this is what we call the diastolic runoff. This is the pressure in the arteries equalizing back down after the increase from systole.

So this continues until we reach the lowest point just before the aortic valve opens. and we begin again. From the dichrotic notch to the start of the systolic upstroke, this is all diastole.

The lowest point that we have here is our minimum diastolic pressure, and is what's going to be registered as our patient's diastolic blood pressure, or DBP. Now, knowing all of these parts, we can actually get a little more information from the waveform. Now, the difference between the peak systolic pressure and the minimum diastolic pressure, this is what we refer to as our pulse pressure. Now, if we take the sum of all of this area under this waveform, this gives us an indication of our patient's mean arterial pressure or their MAP. Now, from here, even more information can be attained with analysis from more advanced monitors.

While this is going to be beyond the scope of this series, it is useful to understand the basic principles here. So here, if we look at the slope of this systolic upstroke, which is how quick the upstroke is going, this is actually correlated to contractility. The area under the systolic curve is a representation of our patient's stroke volume.

This can then be multiplied by the heart rate to determine cardiac output. Then we have the slope of our diastolic runoff is going to be correlated with vascular resistance. So that gives us a good breakdown of the different components of the arterial pressure tracing and what each of those mean. The last thing that I do want to discuss with this pressure tracing here is going to be the alignment with our patient's ECG. So here is actually a corresponding ECG tracing aligned with this pressure tracing.

The thing that really stands out here is that the QRS complex occurs before the systolic upstroke. As a result, the arterial pressure tracing will trail behind the ECG tracing. The reason for this is that the ECG is measuring the electrical impulse. The electrical activity takes place followed then by corresponding muscle contraction in the heart.

There's approximately 180 millisecond delay from the R wave of our QRS complex to the start of the systolic upstroke. All right, so now that we have an understanding of what the arterial pressure tracing is, I want to talk about something that I talked about in the last lesson, but I did want to cover in a little bit more detail here, and that's going to be distal pulse amplification. Now, as mentioned in that previous lesson, the more distal our pressure reading is, the higher the peak systolic pressure that we see.

So again, this is due to the reflection of the pressure wave against those smaller vessels further down the line. And what happens is we see an augmentation of the arterial pressure tracing. That reflective wave is going to augment or increase that systolic blood pressure. So this is shown with the following tracings.

So here we're looking at a tracing from the aorta, the brachial, radial, femoral, and dorsalis pedis. As you can see, the further from the heart we go, the greater the peak systolic pressure and the less defined the dichrotic notch. So to really help to understand this, you need to know that there are actually two pressure waves that are at work here.

So we have the pressure wave of the forward flow of blood, best represented by the aortic pressure wave. So this is as the heart contracts, that pressure wave that's created and is going to travel out and about through this system. Then we have another wave, which is going to be the rebound pressure wave. Again, the further out we go, the stronger this becomes.

These two pressure waves actually get added together and are represented as the arterial pressure tracing that we see, which, as I showed you, will vary depending on where we have our arterial line. All right, now that we understand about our normal pressure tracing, we need to discuss situations where we would see abnormal pressure tracings. The first of these we can talk about.

together and they have to do with something that we call damping. Damping is essentially the influence of reducing our pressure tracing. Now the simplest way that we can think about this is like the loss of energy from a bouncing ball. As a ball is bounced, it loses energy each time and each successive bounce is smaller.

This is essentially damping of the bounce of the ball. Now this is essentially the same concept, but this is now going to be damping our pressure wave. And so I will be talking about this more in the next lesson, but we do use a short, very stiff tubing from the arterial catheter to the pressure transducer to actually record our patient's blood pressure waves. This stiff tubing helps to reduce the loss of energy or that damping of that pressure wave as it travels along the tubing. The length of the tubing can also play a role in this damping as the longer the tubing, the more the damping that we see.

So sometimes we can have an influence on the system that can either increase how much damping can take place, causing a reduction in the energy of the wave, or it can actually work the other way, adding energy to this wave. And so the first situation with damping that I do want to talk about is something that we call over-damped. And this is when there is more damping or more loss of energy than is to be expected. So when this occurs in our arterial line setup, we're actually going to see decreased heights of our waveform, meaning a falsely lowered systolic blood pressure. Now, oftentimes we're also going to see an increase in our diastolic blood pressure, giving us a narrower pulse pressure.

Now there can be a multitude of reasons for this happening, which I am going to discuss in a future lesson looking at troubleshooting. The end result though is a systolic blood pressure and possibly a diastolic blood pressure that are not true. This could of course lead to improper clinical decision making.

Fortunately again, one advantage of the arterial line is that the MAP is generally not going to be impacted, and one of the reasons that we primarily use this in critical care. Now the other damping situation is going to be something that we call underdamped. So sometimes the opposite exists where we actually see more energy added to the waveform giving us less damping.

Now this can seem a little counterintuitive, but I heard a great analogy to remember the difference between overdamped and underdamped. And this analogy uses your hair. If it's wet or damp, then it's going to lie flat. In the case of our A-line, an overdamped pressure will be a flatter pressure.

Hopefully that'll help you guys to be able to distinguish between over and underdamped, and what you would expect to see with your waveform. So the result of underdamping is that we're going to see falsely high systolic blood pressure, and falsely... lower diastolic blood pressure. The added energy causes the waveform to oscillate more, which is why we see this happen.

So this is going to give us a larger pulse pressure. Again, there can be several causes of this, which I will discuss in the next lesson. And again, this can lead to improper clinical decision.

But once again, fortunately, the map will generally remain accurate. All right, so that was kind of a lot to unpack with damping. It's definitely not something that we normally think about in terms of critical... care and the things that we're doing for our patients, but it definitely will have an effect on our A-line and its accuracy.

And so that actually leads right into something that I want to talk about that's called the square wave test. So now that we know our pressure tracing can be inaccurate due to damping, what we are needing is what we refer to as a optimally damping of our waveform. Knowing this waveform is accurate is imperative as some of the treatment options will depend on the accuracy of these numbers.

Fortunately, we have a very easy test that we can do in order to check the dampening of our system, and this is called the square wave test. Now, you may also hear it referred to as the fast flush or the dynamic response test, but they are all the same thing. So the way to do the test is by activating the flush from the transducer. When we do this, the flush rate is drastically increased and causes our waveform to quickly jump up and off of the screen. After just a second, we release the flush, and what we expect to see is an almost as quick drop back down.

and this creates what appears to be the top of a square, hence the name square wave test. Now when the wave form comes back down, it will overshoot our baseline. The normal pressure on the system, aka our patient's blood pressure, is going to push back trying to level back out to its baseline.

This leads to an overshooting above the baseline, and just like the bouncing ball, we see this oscillation until we reach the baseline. Now we expect to see one to two oscillations when we do this test. If we see this, then this we consider to be be optimally damped. Now for the cases of over damping. If our system has too much damping or over damped, we would expect a flatter wave in our tracing.

This also has an effect on the square wave test. The upstroke is not going to be as quick, nor will the downstroke be when it's released. There will be no oscillation when returning to the baseline, and in fact this return to baseline might even be slow and exaggerated. So when this happens, you are going to need to troubleshoot the arterial line and repeat this test. So if our system has too little damping or underdamped, we'd expect an exaggerated waveform.

Once again, this has an effect on our square wave test. The upstroke and downstroke are going to be quick as we expect them, but we are going to see additional oscillations while it's trying to return to baseline. Again, think that we have too much energy, so imagine the bouncing ball analogy. The ball will be bouncing more than expected until that energy is lost.

So if we have more than two oscillations, then this is an indication that we have underdamping. And once again, we're going to need to troubleshoot that arterial line and then repeat this test. All right, so I know the concept of overdamping and underdamping can get a little confusing, especially when you're trying to remember what one's flatter and what one's larger. And so I did want to put up just a couple examples for you guys here. All right, so this is going to be an example square wave test.

So if you perform this test on your patient and this was the square wave test that you got, what would you consider this to be? Hopefully you looked at this and you saw a quick upstroke, a quick downstroke, and just a couple oscillations here. And so this tells us that we actually have an optimally damped arterial line.

And what does this mean for our patient and our A-line? This means that our arterial line is going to be giving us accurate numbers. All right, so again, let's put up another example of another square wave test here. So if you saw this result when you perform the square wave test, what would this be? Well, hopefully, again, you saw that quick upstroke and quick downstroke, but you saw an exaggerated number of oscillations at the end, and this would be an indication of underdamped.

Now, knowing this information, what would you expect to see with your patient's arterial blood pressure tracing? Hopefully, this would tell you that you would see too much energy in the system, thus an exaggerated waveform, giving us that higher systolic and lower diastolic blood pressure. Alright, one last example here.

So here again we do a square wave test and this is what you get. What would this be? Well here hopefully you saw that slower upstroke and that long exaggerated downstroke with no oscillation at the end. This would be an indication of over-damped. Knowing this, what would you expect to see for your patient's arterial blood pressure tracing?

Well, hopefully this should tell you that there is a loss of energy in the system. Therefore, you are going to see a flatter waveform, giving us a lower systolic and possibly a higher diastolic blood pressure. All right, so hopefully some of these examples help to cement some of this information in there.

And then hopefully this lesson was a good review of what it is that we're actually seeing with that arterial pressure tracing. It helps to have an understanding of what's happening at these different points and what that tracing actually tells us. So.

I really hope that you guys enjoyed this lesson. If you did, please go down below and leave this lesson a like, as well as leave me a comment. I love reading your comments and trying to respond to just about everybody there. Also, make sure you subscribe to this channel if you haven't done so already.

Special shout out to the awesome YouTube and Patreon members out there. The support that you guys are willing to show me and this channel is truly valued and appreciated, and so a big thank you to you guys. For the rest of you guys, if you'd be interested in showing support for this channel, you can join the YouTube membership down below.

or head over to the Patreon page and check out some of the additional perks that you guys get for doing just that. You can also support this channel by following some of the links down in the lesson description, as well as checking out some of the awesome t-shirt designs I have down there as well. Make sure you stay tuned for the next lesson in this series, otherwise check out a couple awesome lessons I'm going to link to right here. As always, thank you guys so much for watching, and have a great day.

Transcript for:Arterial Pressure Tracing in Critical Care

Transcript for:
Arterial Pressure Tracing in Critical Care