Chapter 41: Critical Care of Patients With Neurologic Emergencies

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Welcome back to the Deep Dive.

Okay, forget wading through textbooks.

We're jumping straight into the real pressure cooker,

neurocritical care.

Yeah, it's intense stuff.

Today, we're basically distilling that high -stakes knowledge you absolutely need for managing the big neurologic emergencies,

stroke, traumatic brain injury,

TBI, and brain tumors.

Right, these are probably some of the most time -sensitive and honestly complex patients you'll encounter in the hospital.

Our source material gives us a really solid look at the foundations of neurocritical care nursing.

And it really boils down to two main concepts.

Keeping the brain fed, that's perfusion, we'll focus on that with stroke, and keeping the system stable, which is all about cognition, that's our angle for TBI.

Got it.

So that's our mission today, right?

Yeah.

A kind of shortcut to understanding how you rapidly spot and manage when those systems start to fail.

Okay, before we really dive in, let's do a quick terminology check.

Snail down some key terms you're going to hear over and over.

So when we say stroke, we mean infarction, basically cell death, because perfusion got interrupted.

Aphasia, that's trouble with speech or language.

And if you hear hemiparesis or hemiplegia, just think one -sided weakness or paralysis.

Exactly.

These terms are like the everyday language on a neuro unit.

Grasping them helps you catch those subtle signs, the ones that might show up before things get really bad.

Speaking of things showing up before it gets bad, let's start with a really critical warning sign, one that sometimes gets, well, dismissed.

The transient ischemic attack, or TIA.

Ah, the TIA.

It's a contemporary neurologic dysfunction.

The symptoms are definitely real, but they disappear.

So why is this brief interruption in brain blood flow usually gone in under an hour?

Why is it such a huge deal for critical care folks?

Because simply put, a TIA is like a giant flashing neon sign pointing towards an impending stroke.

It's a major warning.

Even though the symptoms might vanish within 30, 60 minutes, maybe stretch out to 24 hours sometimes.

The underlying issue, that temporary perfusion failure, it's still there.

Clinically, you need to be watching for some very specific things, often sensory or motor.

Visual stuff is common, like blurred vision, diplopia, that's double vision or hemianopsia where you lose part of your visual field.

Feel cuts, right.

Exactly, or motor imbalance things like ataxia, that lack of muscle control that messes with their walking.

And if we see someone after a TIA, the immediate job is figuring out the risk, yeah, we use that ABCD assessment tool.

That's right.

ABCD looks at age, blood pressure, the clinical features like that unilateral weakness you mentioned and the duration of the symptoms.

Higher score means higher risk, faster action needed.

Makes sense.

Absolutely.

And the cause behind it usually is a plumbing problem basically.

Carotid stenosis that's hardening and narrowing of the big artery feeding the brain, often because of atherosclerotic plaque building up.

Or it could be an electrical issue stemming from the heart like atrial fibrillation, sending off little clots.

So management is all about stopping the next one, the permanent one.

Exactly.

Lifestyle changes, of course.

But pharmacologically, antiplatelet drugs like aspirin or clopidogrol are key.

And maybe surgery, like a carotid endarterectomy or stenting to open up that artery and boost cerebral perfusion.

Okay, so that sets the stage for the main event.

The full blown stroke, the brain attack.

We know the brain has like zero reserves of oxygen or glucose.

So when blood flow stops, even for a few minutes, infarction happens fast, cell death.

Now if treatment is so time critical, often involving those clot busting drugs, how do we quickly figure out the cause?

Is it a clot or is it a bleed?

Because the treatments are totally opposite, right?

That is the fundamental question right at the start because yeah, treating a clot when it's actually a bleed, that's catastrophic.

So we group them into two big categories.

First, acute ischemic stroke or AIS.

That's caused by an occlusion, a blockage.

And these break down further based on how they formed.

Thrombotic strokes.

They tend to develop kind of slowly, minutes to hours, usually from that plaque buildup, atherosclerosis right in the brain or carotid arteries.

Then you have embolic strokes.

These are sudden,

rapid onset of problems caused by an embolus, a clot that forms somewhere got dislodged and traveled to the brain, often from the heart, especially with AFib.

Right.

And then the second major type, hemorrhagic stroke.

This is where a blood vessel breaks and you've got bleeding happening.

Exactly.

And hemorrhagic strokes are incredibly dangerous.

You've got intracerebral hemorrhage, ICH.

That's bleeding right into the brain tissue itself, often linked to long -term, uncontrolled high blood pressure.

Retention again.

Yeah.

Or sometimes sudden triggers like cocaine use.

Then there's suberacnoid hemorrhage, SAH.

That's bleeding into the space around the brain, the suberacnoid space, often from a ruptured aneurysm or maybe an AVM, an arteriovenous malformation.

Looking at the risk factors,

it seems like there's a huge overlap with heart health.

Smoking, obesity, diabetes,

and especially hypertension, you said that's the most common risk factor.

By far the most common across the board, which, you know, the silver lining is that many of these are preventable.

Yeah.

Following those ABCS of heart health really matters here.

We do need to acknowledge, though, the sources point out a tough reality.

Black men and women and also American Indian and Alaskan Native groups, they face significantly higher rates of stroke and, unfortunately, higher mortality.

That's a critical point.

Health disparities are definitely part of the picture.

Okay.

Let's shift to the acute care setting.

Patient comes through the emergency department doors.

Priority one is obviously ABCS, airway, breathing, circulation.

Always.

But when time is brain, what's the absolute first most critical nursing assessment you need to nail down in those first 10 minutes?

You have to get a complete neurologic assessment done, mandatory within 10 minutes, and it needs to use a standardized tool, usually the National Institutes of Health Stroke scale, the NIHSS.

NIHSS, okay.

That scale is crucial because it helps determine if the patient is even eligible for certain treatments, like the plot busters.

But beyond just the score,

the immediate safety concern is often impaired airway defense.

You gotta check that.

Meaning?

Meaning, can they protect their own airway?

Do they have an adequate cough?

Do they have dysphagia difficulty swallowing?

Because if they can't swallow safely, they're at massive risk for aspiration pneumonia.

That's a serious complication we can often prevent.

Right.

Aspiration, huge risk.

And the specific problems we see, the deficits, they totally depend on where the stroke hit in the brain, don't they?

Absolutely.

Location, location, location.

Left hemisphere damage, that's usually the dominant side for language.

You're gonna expect problems with speech, language, logical thinking.

Things like aphasia or acalculia, difficulty with math.

And the right side.

Right hemisphere injury.

That tends to affect visual spatial awareness.

You might see unilateral neglect, where the patient literally ignores one side of their body or their environment.

They might also be impulsive.

Maybe disoriented.

You mentioned vision issues earlier too.

Yes, vision gets hit often.

A specific pattern is homonymous hemianopsia.

That's blindness in the same half of the visual field in both eyes.

Super important for nurses because you have to position things and approach the patient from the side they can see.

Okay, that makes sense.

Let's talk acute interventions then, specifically for the ischemic strokes, the blockages.

The two big options seem to be IV fibrinolytic therapy and endovascular stuff.

Correct.

The gold standard, if they qualify, is IV alteplas.

That's the clot busting drug.

But the clock is ticking loudly.

How loud?

It must be given within three hours of when the symptoms first started.

Three hours.

That window can sometimes be extended to 4 .5 hours for certain patients, but that three hour mark is the main target.

And giving it its high stakes, dosage is strictly weight -based, 0 .9 milligrams per kilogram.

And there's this metric, door -to -needle time.

From the moment they hit the ED door to starting the drug infusion, the target is 45 minutes.

Forty -five minutes.

Wow.

That's incredibly fast -paced.

It has to be.

And safety during and after that infusion must be intense.

What are the absolute must -do nursing safety priorities when you're giving a drug that powerful?

Okay, number one.

The patient has to be in a critical care setting, like an ICU or a dedicated stroke unit.

The biggest immediate risk is bleeding, specifically converting the ischemic stroke into a hemorrhagic one.

Ah, right.

So you have to be super aggressive about managing blood pressure.

Keep it strictly below 185 systolic and 110 diastolic.

You'll likely be using rapid -acting IV meds, like Lobetalol, to achieve that.

Below 185 -110.

Got it.

And also, to minimize any potential bleeding sites, absolutely no invasive tubes, no NG tubes, no Foley catheters, for at least 24 hours after the alteplase.

Makes sense.

Okay, but what if someone shows up late outside that tight IV window?

Or maybe they have a really big clot in a large artery.

That's where the endovascular interventions come in.

Things like intra -arterial thrombolysis, giving the clot buster directly at the site, or mechanical embolectomy where they physically go in and pull the clot out.

Carotid stenting might also be an option.

These are alternatives, or sometimes used in addition to IV alteplase.

Okay, so looking a bit longer term now, after the immediate crisis,

swallow safety is still a big deal.

Huge deal.

You absolutely must keep the patient NPO nothing by mouth until they've had a formal swallowing assessment, usually by a speech -language pathologist, an SLP.

NPO until cleared.

Clear rule.

Very clear rule.

If dysphagia is confirmed, then the nurse and the SLP work together closely on strategies.

Thicken liquids, specific food consistencies, positioning,

whatever it takes to prevent aspiration.

And what about communication?

And if the stroke caused aphasia,

say expressive or Broca's aphasia, where they understand but just can't get the words out.

Or maybe receptive, Wernicke's, where they can talk but it doesn't make much sense.

Yeah, communication is a massive challenge.

As the nurse, you need patience first and foremost.

Use simple, clear, one -step commands.

Speak slowly.

Give them time.

Avoid rushing or finishing their sentences for them, even though it's tempting.

Pictures or communication boards can help too.

Good tips.

Okay, let's shift gears now.

We've covered perfusion with stroke.

Let's move to cognition and talk about traumatic brain injury, TBI.

Totally different starting point here.

We're not talking about blood vessel blockages initially.

TBI is damage from an external mechanical force.

Like a car crash, a fall, an assault.

Exactly.

It's often an acceleration -deceleration injury.

The head gets suddenly thrown into motion or a moving head suddenly stops.

Either way, the brain slams against the inside of the skull, causes bruising, contusion, or even shearing of nerve fibers.

And we grade the severity using the Glasgow Coma Scale, the GCS.

GCS Core helps classify it as mild, moderate, or severe.

A concussion is generally considered a mild TBI.

But even with mild TBI, some people develop post -concussion syndrome.

They can have headaches, dizziness, trouble concentrating for weeks, even months afterwards.

Okay, so the initial hit is the primary TBI, but you mentioned the real threat often comes later.

Yes, the secondary brain injury.

This is the damage that happens after the initial impact.

And crucially, it's often preventable or at least manageable with good critical care.

And what causes that secondary injury?

It boils down to the brain not getting what it needs,

oxygen and glucose.

Two main culprits are hypotension low blood pressure, specifically a mean arterial pressure, or MAP, below 70 millimeter Hg in hypoxemia.

Low oxygen levels in the blood, like a PO2 below 80 millimeter Hg.

So low flow and low oxygen are the hidden killers after the trauma.

Pretty much.

They disrupt that vital delivery pipeline to the brain cells that are already vulnerable from the initial injury.

And this whole cascade leads straight to that really dangerous complication, increased intracranial pressure or ICP.

Exactly.

The skull is a closed box, right?

There's brain tissue, blood, and cerebrospinal fluid, CSF.

If you add swelling from the injury or maybe bleeding inside, there's nowhere for the pressure to go but up.

What's normal ICP?

Normal is usually considered 10 to 15 millimeters of mercury.

When that pressure stays consistently above 20, that's really detrimental.

Increased ICP is actually the leading cause of death after severe head trauma.

Okay, so monitoring for rising ICP is paramount.

Are there specific types of bleeding inside the head we watch more closely with TBI?

Yes, two main types of hematomas or blood collections.

First, the epidural hematoma, EDH.

This is bleeding between the dura, the tough outer layer covering the brain, and the skull itself.

It's usually arterial bleeding, so it can happen fast.

Arterial means high pressure, fast bleeding.

Right.

The classic, although not always present, sign is the lucid interval.

The patient might get knocked out, wake up and seem okay for a bit, and then suddenly deteriorate rapidly as the hematoma expands.

And EDH is a true neurosurgical emergency.

Need surgery now.

Okay, epidural is fast and arterial.

What's the other one?

The subdural hematoma, SDH.

This is bleeding underneath the dura, between the dura and the brain.

It's usually venous bleeding, so it tends to develop more slowly.

Slower venous bleed.

Yeah.

It can be acute, showing up within hours to days, subacute, maybe days to weeks, or even chronic, developing over weeks to months, especially in older adults or people on anticoagulants.

Got it.

Now, for the critical rescue alert moment, if we need to catch rising ICP super early, what's the absolute first sign a nurse needs to recognize?

Before we get to those really late ominous signs like the Cushing Triad, that scary combo of severe hypertension, wide pulse pressure, and slow heart rate that means brain herniation is likely imminent.

It's the most sensitive indicator,

a declining level of consciousness, LOC.

Even subtle changes matter, increased restlessness, new confusion, more drowsiness.

Any change from their baseline LOC needs immediate attention and reporting.

Don't wait for pupil changes or vital sign changes that LOC changes first.

LOC first.

Crucial point.

So if ICP is rising, how do we manage it from a nursing perspective?

Positioning seems key.

Hugely important.

Standard practice is to elevate the head of bed to 30 to 45 degrees.

This helps promote venous drainage from the head.

Also, keep the head in a midline neutral position.

No neck twisting.

Why midline?

Because turning the head or flexing the neck can compress the jugular veins and impede that venous outflow which would just raise ICP more.

Also, avoid sudden sharp flexion of the hips as that can increase intra -abdominal pressure which indirectly raises ICP.

Okay.

HOB up.

Head midline.

Avoid hip flexion.

Anything else?

Yes.

A really important one.

Avoid clustering nursing procedures.

Don't try to do the bath, linen change, suctioning, and turning all at the exact same time.

Each of those activities can temporarily spike ICP.

Spacing them out gives the brain time to recover between stimuli.

Right.

Don't overwhelm the patient.

We also need to maintain good cerebral perfusion, control fever, sometimes even using therapeutic hypothermia, cooling the patient, and manage ventilation carefully.

Why ventilation?

Because carbon dioxide levels in the blood have a direct impact on cerebral blood vessels.

High CO2 causes vasodilation, widening the vessels which increases blood volume in the head and raises ICP.

Low CO2 causes vasoconstriction which can reduce blood flow too much.

So ventilation needs careful management to keep CO2 in the right range.

Fascinating how interconnected it all is.

Okay.

Finally, let's briefly touch on brain tumors.

Whether they start in the brain primary or spread their metastatic, they also cause major neuro problems, right?

Similar mechanisms to TBI in some ways.

In terms of the consequences, yes.

The tumor itself takes up space.

It causes inflammation in the edema or swelling around it.

It can compress brain tissue and obstruct CSF flow.

All of this leads to deficits and again, that risk of increased ICP.

And the specific symptoms depend on where the tumor is located.

Exactly.

We often talk about supratentorial tumors, those in the main cerebral hemispheres.

They might cause seizures, weakness, or paralysis on one side, cognitive changes, language problems.

Then there are infratentorial tumors located in the brain stem or cerebellum, kind of the lower back part of the brain.

These are more likely to cause problems with balance and coordination, ataxia, maybe nausea and vomiting, or dysfunction of the cranial nerves, controlling eye movements, facial muscles, swallowing.

Treatment can range quite a bit, from chemo and radiation to really specialize things like stereotactic radiosurgery, SRS, like the gamma knife.

Right.

SRS uses highly focused beams of radiation to target and destroy the tumor cells, often without needing general anesthesia or a traditional surgical incision.

It's pretty amazing technology for certain types of tumors.

But often, the main management involves actual brain surgery, a craniotomy, where they open the skull.

Correct.

A craniotomy is a major operation.

And the post -operative care is intense, really focused on preventing complications, especially that rise in ICP from swelling or bleeding at the surgical site.

Okay, post -op priority time.

How does nursing care, specifically positioning, differ after brain surgery depending on the location?

Good question.

It's critical.

For supratentorial surgery up in the cerebrum, you typically want the head of bed elevated 30 degrees, similar to TBI management, to help drainage.

But for infratentorial surgery down near the brain stem cerebellum, the positioning is often flat, or maybe elevated only 10 degrees, and usually side -lying alternating sides.

This is to prevent pressure directly on that posterior fossa incision site and also reduce the risk of aspiration, as cranial nerves controlling swallowing might be affected.

Flat or low for infratentorial, 30 degrees for supratentorial.

Got it.

And neurochecks.

Frequent and meticulous.

Every 15 to 30 minutes, initially right after surgery, checking LOC, pupils, vital signs, motor strength.

You also monitor the dressing closely.

Report any excessive drainage, like more than 50 millimel, in an eight -hour shift immediately, as that could signal a CSF leak or hemorrhage.

Wow, okay.

So let's try to tie this all together.

What's the big takeaway for someone learning critical care facing these complex neuropatients, whether it's stroke, TBI, or post -craniotomy?

What's the common thread?

The absolute bottom line, connecting both profusion and cognition, is that time is brain.

Period.

Early recognition of even subtle changes is everything, and the single most important subtle change to catch.

Declined level of consciousness.

Exactly.

That is your highest priority assessment skill across all these conditions.

Catching that change early can make all the difference.

So your core skills are stabilizing ABCs, making sure the brain is getting enough blood flow, maintaining that cerebral profusion, pressure recognizing and adapting care for those sensory deficits like unilateral neglect or hemianopsia.

And ensuring immediate swallow safety, plus using the right communication strategies for patients with aphasia.

Remember the fast mnemonic for stroke recognition, too?

Face, arms, speech, time to call 911, it's simple but saves lives.

Yeah, it does.

Okay, this deep dive has definitely laid out the essential groundwork for managing these really complex neurologic emergencies.

It's all about safety, profusion, and that constant vigilance.

Now here's a final thought for you to chew on as you continue learning.

We talked a lot about hypertension being a major risk factor and how crucial strict blood pressure control is after, say, thrombolytic therapy for stroke.

So practically speaking, day to day at the bedside, what strategies do you think are as effective for actually maintaining that strict BP control in a patient who might be anxious and pain or just physiologically unstable?

Keep exploring these vital concepts.