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Stroke: Part 1

S1 E10 · The Neuro Power Hour

33 Plays1 month ago

Time to talk stroke! In the first episode of a multi-part series on stroke, Dr. Michael Powers discusses stroke risk factors, the importance of early detection including the value of BEFAST and HINTS, and presentations of common vascular syndromes. Along the way, you'll learn about the differences between ischemic and hemorrhagic strokes, and how despite these differences the functional outcomes between these types of strokes is fairly similar. As 1 in 4 adults over the age of 25 will sustain a stroke in their lifetime, this is a vital topic for all physical therapists regardless of practice area!

Key Takeaways

Prevalence/incidence of stroke
Stroke risk factors
PT role in educating patients on modifiable risk factors
Time is brain
Early detection: FAST, BEFAST, and HINTS
Ischemic vs hemorrhagic stroke - differences in medical management, similarities in functional outcomes
Vascular syndromes: ACA, MCA, PCA, which is most common?
Hemispheric differences

References

All music courtesy of Free Music Archive and used via attribution 4.0 international license.

Intro and Outro: Stylin' by JMHBM
Transitional: Our Reality by Ketsa

Connect

email: neuropowerhour@drmichaelpowers.com
LinkedIn

Transcript

Introduction to NeuroPowerHour

00:00:05

Speaker

I'm

00:00:10

Speaker

Welcome to the NeuroPowerHour. I'm your host and neurological navigator, Dr. Michael Powers, physical therapist, board-certified in neurologic physical therapy, and clinical electrophysiology.

00:00:20

Speaker

Let's get started.

Series Overview: Stroke Awareness

00:00:22

Speaker

Today I'll be talking about stroke, and this will be a first in a multi-part series regarding stroke. It's such a big topic, we're not going to be able to fit everything into one episode, so I'm going to break it down into a series of episodes to tackle the topic of stroke.

00:00:37

Speaker

Today, I'll be focusing on a general overview in terms of prevalence, incidence, overall disability, what are we even looking at in terms of stroke. Then I'll turn my attention towards the importance of early detection, medical management, including some clinical tests and measures we can use to help us in terms of early detection.

00:00:57

Speaker

And then we'll conclude with three common vascular syndromes. I'll also outline which ones are most common and review hemispheric differences. So at the very end of today, hopefully you'll have a good sense of if you're doing a chart review, getting ready to see a patient, you have a good understanding of the most common vascular syndromes, what to look out for for hemispheric differences, and that'll really set you up well for when we start in the next episode talking about how to approach the examination.

Understanding Stroke and TIA

00:01:26

Speaker

A lot of information in today's episode, so let's get right into it. First, let's start with some general terminology. I use the term stroke, and I do want to define what we're even talking about when we say stroke.

00:01:38

Speaker

You may also hear the term cerebrovascular accident, or CVA, and I'll use the term stroke and cerebrovascular accident interchangeably. Essentially what we're talking about with a stroke or a CVA is an interruption of the blood supply to the brain, and this can also be associated with cerebral edema and increased intracranial pressures.

00:02:00

Speaker

So beyond just the interruption of the blood supply to the brain, you can have these secondary effects from increased pressure, which causes further damage. Before going further with stroke, I did want to take a mention or stop to take a mention of the transient ischemic attack or TIA.

00:02:17

Speaker

This looks like a stroke, but with a TIA, the focal neurologic deficits last under 24 hours. So you may hear it also called mini-stroke. In this podcast, I'm going to call it TIA, but if you hear the term mini-stroke, that's what we're talking about.

00:02:34

Speaker

The good news with the TIA is the neurologic symptoms are relatively short-lived, right? They're done or they're mostly resolved within 24 hours. The bad news is that this can often be a precursor or a warning sign of either subsequent stroke and or heart attack. So a mini stroke or TIA is something that absolutely warrants not only further medical workup, but probably involves some lifestyle and medical modifications as well.

00:03:01

Speaker

We'll find as we talk later about risk factors that we'll see most of the risk factors are cardiovascular in nature. So even if the neurologic deficits from a TIA are transient in nature, it's really indicating there's some problems in the system that we need to look out for.

Stroke Impact: Mortality and Disability

00:03:19

Speaker

Turning our attention back to stroke, stroke is highly prevalent. It's the fifth leading cause of death in the U.S. and the leading cause of long-term disability. If you're a physical therapist, you're going to be working with someone who's had a stroke.

00:03:34

Speaker

Even if you're in an outpatient setting or more of an ortho setting, odds are you're going to interact with people who've had a stroke. Maybe you're working with a patient who's got shoulder pain, but they have a prior history of stroke.

00:03:46

Speaker

And the reason I'm saying this is the evidence indicates one in four adults over the age of 25 will experience a stroke in their lifetimes. That's an extremely high incidence and prevalence of stroke. Expanding our view to worldwide, the worldwide incidence is 100 million people.

00:04:04

Speaker

I previously used the bathtub analogy when talking about prevalence and incidence. So prevalence is the water that's in the tub. It's the current existing cases, and worldwide, the prevalence of stroke is 100 million.

00:04:17

Speaker

The incidence, or the water coming out of the faucet, is going to be 12 million per year. So we've got 100 million people living with stroke worldwide, and we're adding 12 million every year into that tub water.

00:04:30

Speaker

Let's then talk about risk factors. We have this very... prevalent condition, what are the risk factors associated with stroke?

Risk Factors for Stroke: Lifestyle Emphasis

00:04:38

Speaker

Common risk factors identified for sustaining a stroke include hypertension, diabetes, cardiac arrhythmias, high cholesterol, smoking and tobacco use, heart disease, obesity, lack of physical activity, poor nutritional status, and lack of sleep.

00:04:56

Speaker

These are all identified as risk factors, and many of these could be considered modifiable or lifestyle risk factors. The two risk factors I want to zoom in on are going to be high blood pressure and smoking because these confer just such an increased risk for stroke that they warrant additional consideration.

00:05:15

Speaker

The data shows that a blood pressure of less than 120 over 80, so not high blood pressure, but what would be considered normal or even a little bit below normal, and I'm using that term kind of an air quote, so if you're maintaining a blood pressure consistently less than 120 over 80,

00:05:32

Speaker

you have less than half of the lifetime risk of stroke compared to someone with hypertension or high blood pressure. Additionally, hypertension increases the risk of recurrent stroke. And what what's happening here is that increased pressure on those blood vessel walls increases is creating increased strain over time, can lead to weakening of vessels, can contribute to aneurysms.

00:05:56

Speaker

So that increased pressure, that increased blood pressure over time, is really setting people up for problems down the road. And I've heard the term sometimes used that hypertension is the silent killer, or it's a silent condition, because the people with hypertension may feel completely fine, but the damage is being done to the blood vessels, and that's kind of hidden.

00:06:19

Speaker

So high blood pressure is a risk factor. It's not something to be taken lightly. I bring this up to take a big picture view for us as physical therapists. Even before someone's had a stroke, we should be working and talking to our patients about modifiable risk factors.

00:06:35

Speaker

If you're working with a patient that has high blood pressure, hopefully we're talking about lifestyle modifications. We're working with them, ensuring they're getting the medical follow-up that they're needing. We're not just looking at high blood pressure as, I did a chart review, and they have high blood pressure, great.

00:06:52

Speaker

No, we really want to take a holistic view, and even though this episode is called Stroke and I'm focusing on patients and condition the condition of stroke, I do want us to think about, well, if I'm working with someone who hasn't had a stroke but has some modifiable risk factors, can we make a difference upstream and hopefully avoid or minimize the risk of stroke down the road? Smoking is the other big risk factor, and it still surprises me, but in this day and age, people some people still smoke, and I'm stunned because we have such overwhelming evidence of the adverse effects of smoking. the risk of stroke is going to be two to four times higher in smokers. So smoking cessation is a key part of modifying the risk for stroke.

00:07:40

Speaker

The other thing I wanna mention is if we think about these risk factors and we're working with someone who's sustained a stroke, It's possible that these individuals have lifestyle patterns, habits that have put them at an increased risk for stroke. And then we're coming in and asking someone whose cardiovascular system maybe is not optimized. And we're asking them or advising them to engage in high-level physical activity, maybe high-intensity gait training.

00:08:07

Speaker

And we know the data says, and we'll get to this in a future episode, high-intensity training is great, but it's good to keep in mind that even though we're conceptualizing the condition of stroke as a neuro condition, it absolutely is a cardiovascular condition as well. And we need to keep that in mind, not only when looking at the risk factors before a stroke, but also down the road when working with our patients who've had a stroke, we need to keep a close eye on how their cardiovascular system is doing.

Early Detection Techniques: FAST, BEFAST, HINTS

00:08:43

Speaker

Now that we've covered risk factors, let's move on to the importance of early stroke detection. The phrase here that I want you to remember, and it's very easy to remember, is that time is brain.

00:08:54

Speaker

When we're talking about early detection for stroke, keep in mind then that time is brain. Early detection is going to be critical to avoid further injury and to initiate the appropriate medical management and treatment. In terms of early detection, for our purposes, I'm going to be talking about the acronyms FAST, BE FAST, and HINTS.

00:09:16

Speaker

We're going to talk about all of these here because they can all be beneficial in terms of early detection of stroke. You may have heard about FAST. FAST is face, arm, speech, and time.

00:09:29

Speaker

And expanding that out a little bit, it's face drooping, arm weakness, speech difficulty, time to call 911. This is commonly put up on stroke educational websites.

00:09:41

Speaker

It's good for community and patient education. And that's been the historic acronym. More recently, FAST has been amended to BEFAST.

00:09:52

Speaker

And what we've added here is BALANCE and I. So with BEFAST, we've got BALANCE changes, BALANCE problems, I or vision changes,

00:10:04

Speaker

face drooping, arm weakness, speech difficulty, time to call 911. So very briefly, BFAST, balance, eye, face, arm, speech, time to call 911.

00:10:18

Speaker

The reason that FAST was amended or expanded to BFAST is the evidence indicated that by adding balance and eye changes, it provided better diagnostic value in terms of acute ischemic strokes.

00:10:31

Speaker

So FAST is a good starting point, but I would recommend for our purposes we expand that out to BFAST because we capture better diagnostic utility. So if you're on the community, you're educating patients in general about stroke detection, I would advise that you go with the BFAST model because that's just going to be overall more useful.

00:10:53

Speaker

One additional point I wanted to make about the face drooping is because there's a condition known as Bell's palsy, which affects the facial cranial nerve, and that can have an entire half of the face drooping. So let me back up.

00:11:07

Speaker

If we're talking stroke or Bell's palsy, you're going to see drooping on half of the face, so either right side or left side of the face. And if it's Bell's palsy, the forehead is affected.

00:11:19

Speaker

If it's a stroke, the forehead is spared. So what may look to be worse, that the half of the face, the entire side, including the forehead, is having difficulty. That's actually not as bad. That's usually indicative of Bell's palsy.

00:11:37

Speaker

Whereas if the forehead is spared, that's usually indicative of stroke. Other differentiators here would be if it's Bell's palsy, it's isolated to the facial nerve, you should not have arm symptoms, balance symptoms, etc. etc So that's a distinguishing feature.

00:11:55

Speaker

i would say, though, if in doubt at all, better safe than sorry. But if you're really wondering about distinguishing between Bell's palsy and stroke, check the forehead, then check for arm and balance because those should be different between Bell's palsy and stroke.

00:12:12

Speaker

Let's then talk about the HINTS exam. This is Head Impulse Nystagmus Test of SKU. This is a test item cluster designed to assess for stroke in patients presenting with acute vestibular syndrome.

00:12:24

Speaker

This was really initially established in for use in the yeah ER. r Patients would come in with acute vestibular syndrome, so dizziness, maybe some vomiting, and providers were wanting to figure out, well, is this from a central cause like a stroke?

00:12:40

Speaker

Or is this from a peripheral vestibular problem? And this test item cluster has excellent diagnostic utility. It's reported to be 100% sensitive and 96% specific for stroke.

00:12:52

Speaker

Remember, the general guideline is highly sensitive tests are helpful for ruling out. So sensitive is your snouts ruling out. Highly specific tests are your spins you're ruling in. So it's got excellent sensitivity and specificity. This test item cluster involves, again, three items, head impulse test, and in order for you to be thinking that it could be going towards a central cause, believe it or not, you would see the head impulse test be negative or normal.

00:13:22

Speaker

A positive head impulse test argues more for a peripheral problem. So here, though, we're not making the consideration of ruling in a stroke based on one individual item. We're going to look at the test item cluster.

00:13:37

Speaker

a normal head impulse test, spontaneous nystagmus, And an abnormal test of skew or seeing the skew would all argue for a central cause.

00:13:49

Speaker

Nystagmus is pretty straightforward, and here we're looking for that to be spontaneous nystagmus. And for test of skew, the test here is the patient's looking at your nose with both eyes open.

00:14:01

Speaker

They cover one eye, and when they uncover the eye, did that eye deviate? So it's in a different position than the eye that was kept open. That it would be a test of skew. And there's videos of this online.

00:14:14

Speaker

When you see it, it looks it just looks wrong. You don't even have to use a medical term. It looks wrong. So head impulse test, nystagmus test of skew, that's your Hintz exam, gives you excellent diagnostic utility.

00:14:27

Speaker

To recap then for early detection, we've got a couple helpful acronyms. We can use FAST, but I've recommended we expand that out to BFAST because the evidence is a little better there.

00:14:38

Speaker

So BFAST, again, is balance, eye, face, arm, speech, time to call 911. And for the HINTS exam, we're combining the head impulse test, nystagmus, and the test of skew.

00:14:53

Speaker

Now it's important, I previously mentioned time is brain, so this early detection is critical.

Stroke Types: Ischemic vs Hemorrhagic

00:14:59

Speaker

It's important to detect stroke early. Once that person is receiving medical care for a suspected stroke, the big thing now to determine is, is this an ischemic or a hemorrhagic stroke?

00:15:12

Speaker

Is this from a clot, thrombus, or amelus? Is there a blockage? Or is this more of what's called a brain bleed? Now, we're going to find that the majority of strokes are going to be ischemic.

00:15:25

Speaker

They're going to come from clots and or conditions producing low perfusion pressures. This lack of blood flow to the brain then, if we have a blood vessel that has a clot, blood cannot get through to the brain tissue.

00:15:38

Speaker

And this lack of blood flow is going to result in tissue injury and death. Along with this, there can be buildup of cerebral edema that causes secondary complications, secondary tissue injury, and tissue death.

00:15:51

Speaker

Hemorrhagic strokes are much less common than ischemic strokes. Hemorrhagic strokes, you can think of these as brain bleeds, maybe a ruptured cerebral vessel, maybe trauma. With hemorrhagic stroke, it's noted that patients may say, this is the worst headache yeah in my life.

00:16:08

Speaker

um I've heard the term a thunderclap headache. So if you're working with a patient or you're working with someone, even if they have a history of headaches, if someone's saying, I'm having the worst headache of my life, or they're using that term thunderclap headache, I would absolutely start on your radar. You're starting to think, could this potentially be a hemorrhagic stroke?

00:16:29

Speaker

With hemorrhagic stroke, in addition to the actual bleeding that's happening, because the bleeding is going into these as extravascular areas, there's going to be a rapid rise in intracranial pressures. This can lead to significant problems, including death.

00:16:43

Speaker

Along these lines, we're going to see a difference in mortality between the two types of stroke, so a different risk of death between the two types. Hemorrhagic stroke has a much higher three-month mortality rate, estimated to be anywhere between 35% and 65%, versus ischemic strokes have about a 15% to 25% three-month mortality rate, so much lower than hemorrhagic stroke.

00:17:11

Speaker

Interestingly enough though, from a physical therapy perspective, regardless of initial stroke type, the rehab course and functional outcomes is going to be relatively similar between the two types.

00:17:23

Speaker

As you're doing then your chart review or looking at the medical history of your patient, we do want to acknowledge and determine what type of stroke someone had, especially if we're in the acute setting because the medical management, pharmacologic management may be a little bit different.

00:17:40

Speaker

However, in terms of prognosis, I would argue that it's really not going to matter. So if I'm doing the chart review, whether someone's had an ischemic or a hemorrhagic stroke, I'm not changing what I think in terms of my ultimate outcomes.

00:17:55

Speaker

Now let's say someone comes into the hospital, they've been medically assessed, and they've been determined to have an ischemic stroke.

Ischemic Stroke Treatment Innovations

00:18:02

Speaker

First line treatment is going to be what are known as thrombolytics.

00:18:06

Speaker

I learned this early on as clot busters. You may still hear that term, and this term makes intuitive sense. If you've got a clot that's producing the problem, you're going to get some medications in there to essentially bust the clot.

00:18:20

Speaker

Really what you're doing is you're dissolving the clot and trying to restore blood flow to the areas previously that didn't have it. Most commonly used initially what' is what's called TPA or tissue plasminogen activator.

00:18:33

Speaker

More recently, there's been a move towards TNK, tenecteplase. These are both in the category of thrombolytics or clot busters. Current evidence I've seen emerging is that TNK may provide better functional outcomes and reduce disability to a greater extent than TPA.

00:18:52

Speaker

So there does seem to be a move towards TNK as compared to TPA. This may be more patient-specific, but we are seeing that transition. The other interesting thing is that the window for administering TNK is expanding.

00:19:06

Speaker

I remember when I was initially working in stroke rehab, I learned we have a critical window. We really talked a lot about that first hour, but now that window has expanded to about four and a half hours for using TNK for acute ischemic stroke.

00:19:23

Speaker

And there's more evidence coming out that for certain patients, the window may be expanding towards the first 24 hours. This is great because that critical window now is expanding. We want to keep in mind still time is brain.

00:19:36

Speaker

We're not wanting to sit on... hemming and hawing as someone maybe having a stroke, but it's good to hear that that window is expanding. Medical advancements are just really incredible in many ways. So that window for ischemic stroke is continuing to expand.

00:19:54

Speaker

And now let's think about this. This really drives home the point of the importance of figuring out whether the stroke is ischemic, because if it is, if the stroke is from a clot, then the use of thrombolytics is 100% appropriate.

00:20:09

Speaker

The medical team is going to want to administer thrombolytics to dissolve the clot, restore blood flow to the area. A lot of early recovery is going to depend upon that early treatment with thrombolytics. I do want to mention, though, everything does carry an opportunity cost.

00:20:26

Speaker

So there is a potential risk of what's called conversion to hemorrhagic stroke with the use of thrombolytics. So the treatment for an ischemic stroke is using a thrombolytic, going to remove the clot and improve blood flow to the area.

00:20:40

Speaker

But because of the mechanism of action of the thrombolytics, it's a known risk that in rare cases, about 2% to 6%, you can get a conversion from ischemic to hemorrhagic stroke. So you could be treating one problem and potentially creating another.

00:20:54

Speaker

Not meant to scare people when I say that, but I do think that's worth mentioning and understanding. And I think that's a good concept to have in mind just in general within medicine and healthcare is there's many things that do carry opportunity costs.

00:21:08

Speaker

We're just getting comfortable with thinking of treatments in general as risks and what's a good treatment in one area could actually be risky or carries a risk in another area. And going along those lines, so we talked about conversion from ischemic to hemorrhagic, let's now talk about management of hemorrhagic stroke.

Managing Hemorrhagic Strokes

00:21:29

Speaker

And absolutely, you're not going to want to treat someone who's had a hemorrhagic stroke with clot busters or thrombolytics. This is someone who's had a hemorrhagic stroke. They're bleeding out.

00:21:40

Speaker

We're not going to administer agents that are going to increase the risk of bleeding out or increase the chances that more blood is going into that extravascular space. This, again, is why it's really important for early detection and early diagnosis, figuring out which category of stroke a patient is having.

00:21:57

Speaker

So if someone's been diagnosed with a hemorrhagic stroke, first-line treatment is going to be about managing that intracranial pressure. And this can be accomplished across multiple modalities, including elevating the head of the bed about 20 to 30 degrees, administration of osmotic agents,

00:22:14

Speaker

and possible surgery such as craniotomy and or aspiration, again, to try and manage that intracranial pressure. To recap then what we've talked about in this segment, early detection is vital.

00:22:27

Speaker

Time is brain. We've got BFAST. We've got HINTS. And then in terms of medical management, really what's important is determining, is this an ischemic stroke? Is this a hemorrhagic stroke? And then treating accordingly.

00:22:40

Speaker

ischemic, looking at thrombolytics, if we can get in within that four and a half hour window, and that four and a half hour window may be expanding. For hemorrhagic stroke, medical management's really going to be focused on managing that intracranial pressure through positioning, possible medication, possible surgery.

Exploring Vascular Syndromes: ACA, MCA, PCA

00:23:03

Speaker

Let's finish up then by talking about common vascular syndromes or what we may see clinically in terms of large vessels that could be either occluded or that could be bleeding. And the ones that we'll mention here today are going to be anterior cerebral artery, middle cerebral artery, posterior cerebral artery, or for ease of saying them, I'm going to abbreviate and say ACA, MCA, PCA.

00:23:26

Speaker

And as someone who started out in the clinic before transitioning over to teaching, I always liked looking at patterns. and And when I was reviewing charts, I really wanted to categorize what I thought I would expect, not to put a bias in there, but really to prep myself for the exam and to plan out what I thought I would see.

00:23:43

Speaker

So I'm going to approach the vascular syndromes here in the same way by discussing what's most common in terms of what you'll see clinically. And then I want to recap a little bit from our prior discussion about the cortex in terms of hemispheric differences.

00:23:57

Speaker

Here I'm kind of conceptualizing. i want this information to be helpful to you clinically. We're reviewing a chart. We see a certain vascular pattern and we've identified a hemisphere. And I think that's going to help you in terms of the patterns that you're likely to see. If we approach it this way, we're gonna see that MCA strokes are going to be by far the most common, about 50 to 60 or so percent of large vessel strokes. So MCA, this is the one that you wanna have a great understanding of because you're gonna see it most of the time clinically.

00:24:29

Speaker

Next most common is going to be PCA, and then ACA is going to be the least common amongst the three. Before we go into detail though about these vascular syndromes, let's recap hemispheric differences.

00:24:41

Speaker

Recall that generally speaking we have some hemispheric differences left to right, Let's talk about the left side first. Remember, for most people, the left side is the dominant hemisphere.

00:24:52

Speaker

Even when you account for people who are left-handed, when you pool everything together for the vast majority of people, left side is dominant, and therefore that is where the language centers are for most people.

00:25:03

Speaker

Those language centers, again, Broca and Wernicke's area. So if you're reviewing a chart and you see someone's had a left-sided stroke, you're immediately starting to think, okay, I need to consider receptive and expressive communication.

00:25:16

Speaker

That's automatically on your radar. Again, that'll be dependent on what vascular syndrome someone had. But right off the bat, just start thinking about, okay, language and communication, I'm going to be on the lookout for if it's left-sided.

00:25:29

Speaker

The other things that yeah I'm really looking for with someone who's had a left-sided stroke is they're going to be more cautious and hesitant. These are the people that may need encouragement. They may be more reluctant to move.

00:25:41

Speaker

Left-sided may also have more difficulty with sequential processing, so keeping instructions simple is going to be key. And then obviously, if it's a left-sided stroke, we're going to see contralateral sensory and motor control issues, so we'll see right-sided hemisensory loss, right-sided hemiplegia.

00:25:59

Speaker

So that's our left side. Really big picture, I'm thinking language, communication, cautious if I had to distill it down. Right-sided, I'm going to really need to pump the brakes with these patients. And I chuckled a little bit because it's not funny, but you have to be on alert more of the time with patients who've had a right-sided stroke.

00:26:19

Speaker

Because these are the individuals that have minimal safety awareness, don't have insight into their deficits, they're at higher risk of having perceptual problems, maybe spatial and or visual deficits.

00:26:30

Speaker

If they're a fall risk, if you don't haven't worked with a patient who's had a right hemisphere stroke, I'm not walking away even when they're up in their chair. I'm really closer to them in terms of a safety perspective until they've proven that they're not a huge safety risk. From a sensory motor perspective, the deficits will be contralateral. So hemisensory loss, hemiplegia is going to be affecting the left side if it's a right-sided stroke.

00:26:56

Speaker

Big picture then, compare and contrast, left-sided hemisphere, we're thinking communication, cautious, right-sided, we're thinking they're the opposite of cautious, poor safety awareness, poor insight, perceptual problems. Those, for me, are clinically the big take-home picture differences between left and right.

00:27:16

Speaker

Let's move on then to talking about the vascular syndromes, and we'll start by talking about MCA. MCA is going to supply the entire aspect of your hit cerebral hemisphere, getting frontal, temporal, parietal lobes, a lot of subcortical structures. The big thing we're going to see here is that contralateral hemiparesis and contralateral hemisensory loss. We can think back to the somatotopic organization.

00:27:40

Speaker

So when we think about the hemiparesis or the one-sided weakness for MCA, we're thinking it's mostly going to be the arm and the face. There is typically lower extremity involvement, but the leg is more spared. So if you think MCA, you're thinking face and arm more involved than leg.

00:27:59

Speaker

So typically you're going to see worse involvement, heavier involvement in the arm and the leg, and then through the recovery process, you might notice that function in the leg returns more quickly than function in the arm.

00:28:11

Speaker

Sensory difficulties or the hemi-sensory loss is going to follow that same pattern. Depending on the hemispheric differences we talked about before earlier, motor speech impairment if it's affecting Broca's area, we may see receptive speech impairment if it's affecting Wernicke's area,

00:28:27

Speaker

You may also get what's called global aphasia, that's non-fluent speech with poor comprehension, makes communication very difficult. However, if it's a right-sided MCA, we're thinking more along the lines of possible perceptual deficits.

00:28:42

Speaker

I would argue, as we're thinking about MCA in general, this is the prototypical or standard stroke that most people think about. If you close your eyes and envision someone who's walking, who's had a stroke, and maybe in your mind's eye you see the involved upper extremity kind of in that flex position, you see that the patient is able to be up and walking, but you might see some circumduction of the leg or you may see some gait deviations.

00:29:09

Speaker

That's pretty typical for an MCA presentation. And again, the key distinguishing feature here is going to be which hemisphere is involved. Left-sided, we're thinking more about communication difficulties. Maybe the person's more cautious.

00:29:22

Speaker

Right-sided, we worry more about safety awareness and perceptual difficulties. Let's move on to the PCA, or the posterior cerebral artery. Here, we're supplying the occipital and portions of the temporal lobe, also the upper brainstem, medbrain, and most of the thalamus. We can see then that we're working here with the occipital lobe, so we have multiple options of challenges with vision.

00:29:44

Speaker

We could be looking at contralateral homonymous hemianopsia. You could even get bilateral homonymous hemianopsia homonymous hemianopsia, and I've practiced a lot to be able to say that term, it's a tongue twister, is the loss of the entire visual field on one side. And it's very interesting if you haven't been exposed to this before, because it's not the loss of an entire side of vision. So it's not as though someone can't see to their left at all.

00:30:14

Speaker

If it's, let's say, a right-sided problem, is that they've lost the left visual field in both the eyes. So it creates an interesting pattern of difficulty seeing.

00:30:26

Speaker

And obviously, if it's bilateral, the person is not blind per se, but their their field of vision or their ability to see is markedly reduced. The other big thing I want to mention here is because PCA supplies the thalamus, you could be talking about thalamic pain in these instances. And I've worked with multiple patients who've had thalamic pain.

00:30:48

Speaker

Thalamic pain is relatively intractable or it's hard to treat. It'll cause spontaneous pain, sensory impairments across all all modalities, and it's challenging because you're working with someone trying to work on improving function, and depending on the person's sensitivity or amount of pain, you may not be able to provide as much tactile cueing or stimulation on the affected side because of the pain response. Finally, ACA, anterior cerebral artery, relatively rare. You might still see it, but the least common of the major large vessel vascular conditions.

00:31:25

Speaker

ACA is supplying parts of the frontal and parietal lobes, basal ganglia, anterior aspect of the corpus callosum. Here, if we have ACA involvement, you can kind of think of ACA being a mirror image in some ways of MCA, or being the same but flipped. And what I mean by that is MCA, we said face and arm are most involved, leg less so.

00:31:48

Speaker

ACA is going to be opposite. So ACA is going to have more leg involvement, face and arm less so. And as physical therapists, the hemisensory loss, the hemiplegia, that's some of the biggest impairments we're working on.

PT Involvement in Stroke Prevention

00:32:03

Speaker

So I think it's helpful to keep in mind ACA is in many ways the inverse from a hemisensory loss, hemiplegia perspective.

00:32:11

Speaker

of MCA. To summarize then, we've laid the foundation for thinking about stroke. Hopefully now you have a good understanding that stroke is very prevalent. Remember we said globally 100 million cases worldwide with 12 million cases being added per year.

00:32:28

Speaker

So you're going to see patients with stroke if you're out on clinicals, when you're in clinical practice. No matter what you're setting, you're going to be working with patients who've had a stroke. Remember, it's estimated that one in four adults over the age of 25 will experience a stroke sometime in their lifetimes. There's multiple cardiovascular and lifestyle risk factors associated with stroke, and I would highly encourage all of us to think about our role as PTs in educating our patients on these risk factors even prior to stroke.

00:32:59

Speaker

And I don't think we need to come off as preachy. I think we need to provide the space to have these conversations. I think we need to care enough and see patients holistically to really be working with our patients on lifestyle modifications for overall health, not just from a stroke perspective,

00:33:15

Speaker

But again, since this episode is titled Stroke, really thinking about those risk factors that we can modify for stroke risk.

Episode Recap: Key Takeaways

00:33:22

Speaker

I think if we can help modify some of these risk factors, we're really helping our patients out tremendously.

00:33:28

Speaker

Remember that time is brain, so early detection is vital. Keep in mind your acronyms of BEFAST and HINTS. BEFAST, again, balance, eyes, face, arm, speech, time.

00:33:44

Speaker

Hence, it's gonna be head impulse nystagmus test of skew. Then once the diagnosis of stroke is made, it's really important for the medical team to determine is this an ischemic stroke or a hemorrhagic stroke. Hemorrhagic strokes carry a higher mortality risk early on,

00:34:01

Speaker

However, over time, ischemic and hemorrhagic strokes have similar functional outcomes. Ischemic strokes are going to be treated via thrombolytics. We've got a four and a half hour window. That window may be expanding.

00:34:13

Speaker

Hemorrhagic strokes are going to be treated across a combination of treatments aimed to manage intracranial pressures. As it relates to the vascular syndromes, MCA, middle cerebral artery, by far the most common. That's what you're going to see clinically.

00:34:28

Speaker

Big PT take-home there is for MCA. The face and the arm are more involved in terms of hemisensory loss, hemiplegia. leg a little less so involved, and then keep your hemispheric differences in mind.

00:34:41

Speaker

Left side is going to be communication centers, more cautious. Right side is going to be perceptual difficulties and less safety awareness, less insight.

00:34:52

Speaker

So as you're reviewing your chart, hopefully that helps you. Most likely you're going to see MCA. You've got your hemispheric differences in mind. It'll give you a little bit of an idea of what to expect as you're prepping your clinical exam.

00:35:04

Speaker

So thanks for listening to the NeuroPowerHour. I'm your host, Dr. Michael Powers, and I hope to catch you next time to continue learning.