Chapter 23: Eye, Ear & Neurologic Conditions in Children

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Welcome back to the Deep Dive.

We are tackling something today that I think is going to be incredibly useful, not just for the nursing students in our audience, but really for anyone who has ever looked at a toddler and thought, how do you even know if that little system is working right?

It's a great question, a really fundamental one,

because unlike adults, they can't tell you, hey, I have a blind spot in my left eye or my ears are ringing.

Not at all.

You have to be a detective.

A detective, exactly.

You're piecing together clues from observations, what the parents tell you from these very subtle signs.

A detective with a stethoscope.

So we're focusing specifically on the learner today.

That's our listener persona who wants the high yield info, the really critical stuff, wants it to stick.

Right.

Not just memorization for a test, but deep understanding that you can apply on the floor.

And our source material is the heavy hitter.

Chapter 23 from Leifers Introduction to Maternity and Pediatric Nursing in Canada.

A classic text.

It's a cornerstone for a reason.

And we're going to be very disciplined today.

We are walking through this chapter in the exact order it's written.

No jumping around.

No jumping around.

We're starting with the eyes, moving to the ears, and then diving deep into the nervous system.

Which makes sense logically, doesn't it?

It's like we're starting with the sensory input, how the child perceives the world, and then moving to the processor, the brain.

That has to make sense of it all.

Precisely.

And because this is a Canadian text and we want to be true to that, we are going to be highlighting some specific guidelines from the Canadian Pediatric Society, or CPS.

Okay, good to know.

So if you're practicing up north, pay close attention.

But honestly, the physiology, the core concepts, they apply everywhere.

All right, let's do it.

Section one, the eyes.

And when I say beginning, I mean beginning.

The embryology here is faster than I expected.

It's surprisingly fast.

It's one of those things that just, it blows your mind a little bit.

If you look at the development timeline, the eyes actually begin as an outgrowth of the forebrain.

An outgrowth of the brain itself.

Yes.

When the embryo is just four weeks old.

Four weeks.

I mean, think about that.

Most people barely know they are pregnant at that point.

And the entire architecture for vision is already being laid down.

But the text makes a really critical distinction, and I want to zero in on this.

The difference between the eye being formed and the eye being ready.

A huge, huge difference.

And this is vital for anyone working in a neonatal intensive care unit, the NICU.

It comes down to the retinal vessels.

The blood supply.

The blood supply that feeds the back of the eye, the retina.

Those muscles don't fully vascularize.

They don't finish growing until 40 weeks of gestation.

So a full term baby.

Right.

So if you have a baby born at say 28 or 30 weeks, those vessels are incomplete.

They're fragile.

They're not ready for the outside world for the changes in oxygen pressure.

And this sets the stage for what?

What's the risk here?

This is the setup for a condition called retinopathy of prematurity.

We see it in preemies.

It's like the hardware just wasn't finished installing before the system was turned on.

It can lead to serious vision problems, even blindness.

Okay.

So that's the preemie.

Now let's assume we have a healthy full term newborn.

The parents are gazing into the baby's eyes.

What is the baby actually seeing?

Because there's this myth that they are blind at birth.

They aren't blind, not at all, but they definitely aren't seeing 4K high definition.

Not even close.

The text estimates newborn visual acuity at around 2 ,400.

Let's unpack that number for a second.

2020 is the standard we all know, 2 ,400.

That means what I can see clearly at 400 feet, the baby has to be 20 feet away to see.

Is that the right way to think about it?

That's exactly it.

It's extremely blurry.

If you hold a finger up from across the room, they probably don't even register it as a shape.

It's all just light and shadow.

But they can focus, can't they?

They can, but it's a very limited focus.

The text notes that they can fixate on an object, hold their gaze, but only for a few seconds.

Crucially, only if it's about 8 to 12 inches away from their face.

Which conveniently is the exact distance between a baby's face and the mother's face during breastfeeding.

Evolutionary biology at its finest, isn't it?

They are hardwired to see what they absolutely need to see.

The caregiver's face, the source of food and comfort, everything else is just background noise.

And the text mentions that the shape of the eyeball is actually different in newborns.

That surprised me.

It is.

It's less spherical, a little shorter.

As the child grows, the globe of the eye actually changes shape and elongates, which is part of what improves that acuity.

So it's not just the brain learning to see.

The hardware itself is upgrading.

The hardware is still under construction.

By age two or three, they're getting close to 2030.

And then typically by age six or seven, that's when they finally hit that 2020 standard.

There's a developmental milestone timeline here that seems really important for nurses to have memorized because missing these cues could mean delaying a critical diagnosis.

Let's walk through the first six months.

Let's do it.

So first month,

newborn, they stare.

They'll fixate briefly on that face eight inches away, but they aren't tracking objects yet.

If you move a toy slowly from left to right, they'll just lose it.

The eyes don't move together smoothly.

Then we get to the two to four month window.

What changes?

This is the big shift.

Now they can coordinate those eye muscles enough to follow an object.

We call it tracking.

It should be smooth.

If you have a four month old who still just stares blankly while you wave a bright red toy in front of them,

that's a red flag.

Something isn't connecting.

And what about tears?

I was surprised by this.

I thought babies cried tears immediately.

They make the sound, but the plumbing isn't quite ready yet.

The lacrimal ducts, the tear ducts, they don't usually produce a full flow of tears until about four to five months of age.

So a dry cry in a two month old is totally normal.

Totally normal.

A dry cry in a six month old, on the other hand, might make you start thinking about dehydration.

Context is everything in pediatrics.

I want to talk about the connection the text makes between vision and motor skills.

I think often we silo these things, he's clumsy, check his legs, but the text says, no, check his eyes.

It's the concept of hand -eye coordination,

but stripped down to its absolute basics.

Think about a six month old.

One of their big developmental tasks is passing a block from the left hand to the right hand.

To do that, the eyes have to lock on to the object, the brain has to calculate the distance and the relative position of both hands, and then it has to guide the other hand to meet it in the middle.

It's an incredibly complex neurological feat.

And if the vision is blurry, or if they lack depth perception?

They can't do the transfer.

They'll miss, they'll drop it.

So a delay in that specific motor milestone could actually be a vision problem in disguise.

That's a great clinical pearl.

And the book mentions depth perception specifically kicks in around nine months.

Around nine months, yes.

Which is right when they start crawling and pulling to stand.

It's no coincidence they need to be able to perceive depth to navigate the world safely.

If a child is really terrified of movement or falls constantly, you have to ask,

can they see where the floor is?

Can they judge that distance?

That leads us right into screening.

We can't just wait for them to bump into walls.

What does the Canadian Pediatric Society recommend for formal vision checks?

They are quite specific about this.

They recommend a formal vision screening for every child between the ages of three and five.

This is the critical preschool check.

Why that window specifically, three to five?

Because the visual system is still plastic.

It's still developing and adaptable.

If you catch amblyopia, a lazy eye, or a significant refractive error at age four, you can often intervene and fix it completely.

And if you wait until age ten?

If you wait until age ten, those neural pathways in the brain are pretty much cemented.

You've likely missed the boat for effective treatment.

The brain has learned to ignore that eye.

Let's get into the nitty gritty of the assessment, what you're actually doing in the clinic.

The text references figure 23 .2, which is about pupil response.

It uses a notation format that I've seen in charts, but it can look like algebra if you don't know the code.

It says 31B.

Let's decode that because it is the industry standard shorthand.

It saves a lot of writing.

You have three variables packed in there.

Okay.

The first number is the pupil size in millimeters at rest in normal room light.

So let's say it's a three, a three millimeter pupil.

Okay, that's the starting point.

You shine your pen light directly into that eye.

The pupil should constrict, right?

It should get smaller to block out the bright light.

The second number is the size after the light stimulus.

So if it shrinks down to one millimeter, you write 31.

So start size and size make sense.

Exactly.

And the letter tells you about the speed of that reaction.

B stands for brisk.

It's snapshot fast.

That's a healthy normal response.

That's what we want to see.

What are the bad letters?

What are the warnings?

S for sluggish is a concern.

It constricted, but it took its sweet time about it.

That can suggest some swelling or pressure on the nerve.

And N for nonreactive.

You shine the light and absolutely nothing happens.

And that's a huge red flag.

That is a major neurological alarm bell.

And obviously you are comparing the left eye to the right eye.

Always.

Symmetry is the golden rule in a neuro exam.

If one eye is a perfect 31B and the other is a 54S, you have a massive localized problem.

You need to investigate immediately.

Beyond the flashlight, what are the observational red flags?

The things a nurse or parent might notice.

The text lists things like head tilting.

Head tilting is a classic condensation mechanism.

If a child has double vision, which is called diplopia, they learn very quickly that if they tilt their head to a specific angle, the images from their two eyes will align.

So they're self -correcting.

They're self -correcting.

So a parent might just think, oh, he just looks cute when he tilts his head like that.

But the nurse sees a potential strabismus or cross eyes.

It's a sign the eyes aren't working together.

And squinting.

Squinting is another one.

It physically changes the shape of the eye slightly.

And more importantly, it limits the amount of light entering, which can sharpen the focus temporarily.

It's nature's way of trying to create a pinhole camera effect to see better.

The text also brings up epicansal folds.

Can you explain what those are?

Sure.

These are the small skin folds at the inner corner of the eye, the campus.

In children of Asian descent, these folds are a very common, completely normal anatomical variation.

But if you see prominent epicanthal folds in a child of non -Asian descent, especially when coupled with other signs like a flattened nasal bridge or low -set ears, it can be a marker for certain chromosomal abnormalities.

The most well -known is Down syndrome or trisomy 21.

The text also warns that these folds can cause an optical illusion, right?

Yes, and this is a really important point to avoid unnecessary worry.

It's called pseudostrabismus.

Fake strabismus.

Exactly.

The fold of skin covers the inner white part of the eye, the sclera.

So it looks like the eye is turned inward, like it's crossed, even though the visual axis is perfectly straight.

The nurse needs to be able to use a light reflex test to tell the difference between a true eye turn and this illusion.

Let's move to the warning signs table in the chapter table 23 .1.

We can't list them all, but it highlights a few that require an immediate referral to an ophthalmologist.

The absolute do -not -pass -go, do -not -collect $200 signs are these.

Leuka curia, we'll talk about that more with tumors later, but it's that white reflex in the pupil.

Irregular pupils, pupils should be round.

If one looks like a keyhole or a teardrop, that suggests a congenital defect or a past trauma.

Untamed.

And pain.

A child with persistent unexplained eye pain needs to see a specialist.

It's not something you just watch and wait on.

Let's transition to the common conditions.

The bread and butter of pediatric eye care that you'd see in a primary care clinic.

Infection and inflammation.

Okay, so we have to start with the eyelid.

The first one is blepharitis.

This is simply an inflammation of the lid margins.

It looks like dandruff on the eyelashes.

Crusty, scaly, red, and itchy.

It's often caused by staphylococcus aureus.

And then there's the stye.

Everyone knows what a stye is.

A stye or a hortiolum.

It's essentially a pimple on the eyelid.

It's an infection of one of the tiny sebaceous glands right at the base of an eyelash follicle.

It's tender, it's red, it's swollen.

Treatment for both of these is pretty low tech, right?

Very low tech.

The cornerstone is warm compresses.

And I mean warm, not hot.

You aren't trying to squeeze it or pop it.

You apply warmth to help liquefy the blockage in the gland and encourage it to drain on its own.

Good lid hygiene is key.

Okay, now for the big one.

Conjunctivitis.

Pink eye.

The scourge of preschools and daycares everywhere.

It is so highly contagious.

And the text really emphasizes the importance of distinguishing between viral and bacterial causes because that dictates treatment.

How can you tell the difference?

The biggest clue is the discharge.

Bacterial conjunctivitis usually has that thick yellow -green purulent discharge, the kind that crusts the eyes shut in the morning.

Viral is often more watery, maybe a little stringy mucus and is frequently accompanied by other cold symptoms.

The nursing care here focuses heavily on preventing the spread.

And there's a specific wipe direction role mentioned.

Yes, inner cancers downward and away.

Why that specific vector?

Why does it matter so much?

Think about the anatomy of the face.

The tear duct, the nasolacrimal duct, drains into the nose right at that inner corner.

If you wipe up or in, you risk pushing that bacteria right into the tear duct system, which can cause a secondary infection.

And if you wipe across the nose, you could easily contaminate the other eye.

So you always wipe down and away from the face to clear the debris safely and prevent spread.

One clean tissue per wipe.

Good to know.

And what's the rule for sending a kid back to school or daycare?

The text is clear on this.

Once antibiotic drops or ointment have been used for a full 24 hours, the child is generally considered non -contagious and can return to their activities.

Let's talk about a condition that can mimic pink eye but isn't an infection at all.

Decreosthenosis.

Blocked tear ducts.

This is a purely mechanical issue.

It's very common.

In about five to seven percent of newborns, the thin membrane at the bottom of the tear duct just doesn't pop open at birth like it's supposed to.

So the tears have nowhere to go.

Exactly.

They can't drain into the nose, so they just pool in the eye and spill over under the cheek.

Parents will say, my baby's eye is always watery.

So you'll have a watery eye, maybe some eucacy gunk from the pooling.

But the eye itself, the white part, isn't red and angry like it is with pink eye.

Correct.

That's a key differentiator.

And the treatment is very hands -on.

The nurse teaches the parents how to massage the lacrimal sac.

How does that work?

You place your clean finger right at the inner corner of the eye next to the nose, and you apply firm downward pressure.

You're trying to use hydrostatic pressure to pop that little membrane open from the top.

It resolves on its own in most cases with this massage.

OK, moving from plumbing issues to trauma, ifema.

This sounded painful just from reading the word.

It is, and it's scary to look at.

A hyphaena is blood pooling in the anterior chamber of the eye.

That's the space between the clear cornea and the colored iris.

And this is usually from a direct hit.

Usually from a direct impact.

A baseball, a fist, an airbag, even a hard snowball.

You look at the eye, and you can literally see a fluid level of red blood sitting at the bottom of the colored part of the eye.

It's a medical emergency.

The treatment protocol is strict bed rest.

Very strict.

And specifically elevating the head of the bed 30 to 45 degrees.

Why the specific angle?

It's all about gravity.

You want that blood to settle down at the bottom of the chamber away from the optical axis, which is the pupil.

This prevents it from staining the cornea or blocking vision.

It also helps lower the intraocular pressure, which is usually high after an injury like this.

And there is a huge medication warning here, a big do not use E sign.

Yes, no NSAIDs.

That means no ibuprofen, no duproxen, no aspirin.

Why not?

Because those drugs inhibit platelet function.

They thin the blood.

You have an active bleed inside the eyeball.

The absolute last thing you want to do is make it harder for the body to form a clot.

Tylenol or acetaminophen is okay for pain, but you have to steer clear the anti -inflammatories.

Let's shift gears now to visual acuity dysfunction.

The stuff that leads to glasses.

Refractive errors.

This is your classic nearsightedness, which is myopia and farsightedness, which is hyperopia.

The text makes an interesting point that most children start out a little bit hyperopic, a little farsighted, and then they grow out of it as their eyeball elongates.

But myopia nearsightedness is on the rise.

It is.

And a big part of the assessment is figuring out how to test a three -year -old who doesn't know the alphabet.

You can't just put a standard Snellen chart up and say, read line four.

Right.

So what do you do?

We get creative.

We use what's called the tumbling E chart.

It's a chart full of the letter E, but they're all facing in different directions, up, down, left, or right.

And you ask the child.

You turn it into a game.

You say, this is a little table with three legs.

Point your fingers the same way the legs of the table are pointing.

For even younger kids, we might use picture cards with simple objects, like a house or a car.

I want to spend some real time on strabismus.

Cross eyes.

Because I think people sometimes dismiss it as just a cosmetic issue.

His eye wanders a bit.

It gives him character.

But the brain does something really drastic if you ignore this.

It does.

This is a critical concept for every nursing student to understand.

It's called suppression.

If the eyes are misaligned, say one is looking straight ahead and the other is turned inward,

the brain is receiving two completely different pictures.

The brain hates that.

It cannot function with constant double vision.

So what does it do?

It can't fuse the images.

It acts like a video editor and just cuts the feed from the wandering eye.

It actively suppresses the signal.

It learns to completely ignore it.

And if it ignores that signal for too long during those critical developmental years?

That neural pathway from the eye to the brain atrophies from disuse.

The eye itself might be physically perfect, but the brain forgets how to use it.

That is amblyopia, which we call lazy eye.

And after a certain age, usually around six or seven, you often can't get that vision back.

It can be permanent functional blindness in that eye, strictly from being ignored by the brain.

And that explains the treatment, which I think a lot of parents find confusing and counterintuitive, the patching paradox.

Right.

The treatment is to put a patch on the good eye.

And the kid hates it, I imagine.

Of course they hate it.

You just covered up the only eye they can see clearly with.

Now they are forced to stumble around using their blurry, weak, lazy eye.

But that struggle is the therapy.

How so?

It forces the brain to pay attention to that input again.

It reestablishes and strengthens that neural connection.

It's literally weightlifting for the visual cortex.

The text distinguishes between paralytic and non -paralytic strabismus.

What's the difference?

Non -paralytic is the more common type.

It's usually due to a muscle imbalance that the child is born with.

The degree of the eye turn is constant, no matter which way they look.

Paralytic is more concerning.

Why?

Because it means one of the cranial nerves that controls eye movement is damaged or paralyzed,

so the eye won't move in a specific direction.

If a child suddenly develops crossed eyes after a fall or with a headache, you have to worry about nerve damage or increased intracranial pressure.

It's a much more urgent situation.

Before we close the book on eyes, we have to discuss the most serious condition in this section,

retinoblastoma.

Yes, this is a malignant tumor of the retina.

It's the most common intraocular cancer in children.

There is a classic sign that often shows up in family photos, and parents are sometimes the first to spot it.

The cat's eye reflex,

or the medical term leukocuria.

Normally, when you take a flash photo, you get red eye, right?

That's the light from the flash reflecting off the blood -rich retina at the back of the eye.

In a child with retinoblastoma, the tumor is sitting on the retina, blocking that view.

So instead of a red reflection, you see a white or yellowish glow in the pupil.

It looked like a cat's eye caught in a headlight.

So if a parent ever shows you a photo on their phone and says, why does his eye look weird here, you don't ignore it.

Never.

You tell them to go see an ophthalmologist immediately.

That is an urgent referral.

Early treatment can save the eye and the child's life, often using laser therapy or chemotherapy.

Late treatment often means enucleation, the surgical removal of the eyeball, to stop the cancer from spreading up the optic nerve to the brain.

Wow.

Okay, that's a lot for the eyes.

A really comprehensive overview.

Shall we travel down the Eustachian tube?

Let's do it.

Section two, the ears,

hearing and balance.

We hear about ear infections constantly in pediatrics.

It feels like a rite of passage for toddlers.

But why?

Why are kids so much more prone to this than adults?

It all comes down to the architecture,

specifically the architecture of the Eustachian tube.

This is the little tube that connects the middle ear space behind the eardrum to the back of the throat.

And its job is to drain fluid and equalize pressure, like when your ears pop on a plane.

Exactly.

Now, in an adult, that tube is relatively long and it's angled steeply downward.

Think of it like a steep water slide.

Any fluid that gets in there drains easily by gravity right into the throat.

Okay, so it's efficient.

Very.

But in an infant or a toddler, that tube is much shorter, it's wider, and this is the most important part, it's almost completely horizontal.

So the water slide is flat.

Exactly.

It's less of a slide and more of a swamp.

The fluid just sits there.

It stagnates.

And because the tube is shorter and wider, bacteria from the throat can easily swim upstream and set up shop in that warm, stagnant fluid.

It's a recipe for infection.

There is an assessment technique the text highlights for actually looking into the ear with an otoscope, the pinna pole.

Yes, and it's different for kids versus adults.

Because the ear canal is curved differently in a small child, to get a straight line of sight to the eardrum in a child under three, you need to gently pull the pinna, the outer ear down and back.

And for an adult.

In an adult or older child, you pull up and back.

If you pull the wrong way on a toddler, you're just going to be looking at the canal wall and you'll miss the pathology on the eardrum.

And speaking of the outer ear, the text mentions checking its alignment on the head.

This is part of your general inspection of any newborn or child.

You draw an imaginary line from the outer corner of the eye, straight back to the back of the head.

The very top of the ear where it connects to the scalp should fall on or just above that line.

And if it's below that line, they have low said ears.

Low said ears can be a subtle marker for a variety of congenital anomalies and genetic syndromes.

Interestingly, the ears and the kidneys develop at the exact same time in the embryo.

So if I see malformed or low set ears, one of my first thoughts is, I wonder how those kidneys are working.

It's a potential clue.

Let's talk about otitis externa versus otitis media,

or swimmer's ear versus the standard middle ear infection.

How do we tell them apart clinically?

It's all about the location of the pain.

Otitis externa is an infection of the skin of the outer ear canal.

It's essentially like having a boil or a pimple in your ear canal.

It's superficial.

So if you touch the external ear, if you wiggle the pinna or press on the tragus, that little flap of cartilage in the front, the pain is excruciating.

So you can use the wiggle test.

Exactly.

If they scream when you wiggle the ear, you're thinking otitis externa.

Otitis media is an infection deep behind the eardrum.

Wiggling the outer ear usually doesn't hurt nearly as much.

The pain is a deep internal throbbing pressure.

And when you look inside with the otoscope, the eardrum will be bulging and bright red.

The textless bottle propping as a major and preventable risk factor for otitis media.

This is a huge education point for parents.

If you prop a bottle up for a baby who is lying flat on their back, gravity pulls the milk or formula to the back of their throat.

And because of those flat horizontal eustachian tubes we just talked about, the milk can easily pool there and wash right into the middle ear space.

And milk is full of sugar.

It's basically serving up a fae to any bacteria that happen to be around.

Here is some warm sugary liquid in a dark damn space.

Enjoy.

It's almost guaranteed to cause an infection.

So we always teach parents to feed the baby in a more upright position.

The treatment for these infections has shifted over the years.

I remember getting pink amoxicillin for every single earache.

Now the text suggests a wait and see approach.

It's called watchful waiting.

We came to realize that a huge percentage of ear infections are actually viral, so antibiotics won't touch them.

Or they're mild bacterial infections that the child's own immune system can clear in 48 hours.

And we were creating superbugs.

We were creating antibiotic resistance by throwing amoxicillin at everything.

So now the Canadian Pediatric Society guidelines say that if the child is over six months old and not severely ill, no high fever, no intense pain, we manage the pain with acetaminophen or ibuprofen and we wait 48 to 72 hours.

If it's not better by then, then we prescribe antibiotics.

But for the chronic kids, the ones who have infection after infection month after month, we have surgery.

Meringotomy.

A moringotomy is when an ENT surgeon makes a tiny incision in the eardrum to relieve the pressure and drain out all the trapped fluid or pus.

Often, during that same procedure, they'll insert tympanoscomy tubes.

Ear tubes.

Right.

They're tiny little plastic or metal grommets that they place in that incision to keep the hole open.

This allows air to get into the middle ear and fluid to get out, effectively bypassing the dysfunctional eustachian tube.

And a classic call a clinic nurse gets is from a parent panicking because the tube fell out.

I found a tiny piece of plastic in his earwax.

And we can reassure them that this is good news.

It means the ear has healed and the eardrum has naturally pushed the tube out on its own.

They usually last about 6 to 12 months and then fall out.

Let's briefly touch on hearing impairment.

The text differentiates between conductive and sensorineural loss.

A simple way to think about it is this.

Conductive hearing loss is a roadblock.

There's something physically blocking the sound waves from getting to the inner ear nerve.

It could be earwax, fluid from an infection, or a hole in the eardrum.

It's mainly a volume problem.

And sensorineural.

Sensorineural is a hardware failure.

The nerve itself, the auditory nerve, or the delicate hair cells inside the cochlea are damaged.

This is often permanent and it affects the clarity of sound, not just the volume.

Speech can sound distorted.

And when communicating with a hearing impaired child, the text gives some specific do's and don'ts.

Absolutely.

Do get down on their eye level, face them directly so they can see your lips and facial expressions, speak clearly, and use short, simple sentences.

What shouldn't you do?

Don't shout.

Shouting actually distorts the sound and can be painful for someone with a hearing aid.

And surprisingly, the text advises not to over -exaggerate your lip movements.

Really?

I would have thought that helps with lip reading.

You would think so, but it actually distorts your face and makes the normal, subtle cues of lip reading harder to decipher.

Just speak naturally and clearly.

One final air topic.

Barotrauma.

Airplane ear.

The bane of every parent flying with a baby.

This goes right back to that Eustachian tube in pressure equalization.

On descent in an airplane, the cabin pressure increases, pushing the eardrum inward.

It's painful.

We need to pop our ears to let air into the middle ear and push it back out.

But a baby can't chew gum or hold their nose and blow.

Right.

So what do we do?

We make them swallow.

The best way to do that is to feed them.

Breastfeed or give them a bottle during descent.

The act of sucking and swallowing engages the very muscles that pull the Eustachian tube open.

It's natural autoinflation.

A great tip.

Okay.

Moving on to the heavyweight champion of this chapter.

Section three.

The nervous system.

The command center.

This is where the stakes get very high, very fast.

The assessments are critical and the warning signs can be subtle.

Let's start with development again, just like we did with the eyes.

The neural tube.

This is the embryonic structure that eventually becomes the brain and the spinal cord.

And the timeline here is absolutely unforgiving.

The neural tube fuses.

It basically zips itself shut from the middle outwards during weeks three and four of gestation.

Weeks three and four.

Again, that's a theme before many women have even confirmed they're pregnant.

Exactly.

This is the entire basis for the public health recommendation that all women of childbearing age should take a folic acid supplement.

Not just women who are actively trying to conceive.

If you wait until you get that positive pregnancy test, the neural tube has already closed.

Or it has failed to close.

The window of opportunity for prevention is over.

When we assess the nervous system in a child who is sick or injured, we can't use adult tools directly.

The Glasgow Coma Scale, or GCS, is the gold standard for assessing level of consciousness.

But the verbal section asks questions like, what year is it?

Or who is the prime minister?

Which a six month old is obviously going to fail.

So we use the modified pediatric GCS.

It's adapted for preverbal children.

We assess the verbal score based on age -appropriate sounds and interactions.

Can you give me an example of how that works?

Sure.

A perfect score of five.

The best verbal response would be an infant who smiles, coos, and babbles appropriately.

A score of four is a child who is crying, but they can be consoled.

A three is a persistent, inappropriate cry or a high -pitched scream.

They are inconsolable.

And lower than that.

A two is just grunting and responsive pain.

And a one is no response at all.

So you see, we are judging the quality of their vocal interaction with the world, not the content.

There is a vital sign pattern mentioned here that is absolutely crucial for nurses to recognize.

It relates to increased intracranial pressure, or ICP.

Now, in shock, we usually see low blood pressure and a high heart rate.

Right.

The heart race is to try to compensate for the low pressure and perfuse the organs.

But with increased ICP, when they're swelling or bleeding inside the rigid box of the skull, we see the opposite pattern.

This is a late and very ominous sign called Cushing's response or Cushing's triad.

As the pressure builds up inside the skull, the brain starts to get squished and it's not getting enough blood flow.

It starts to suffocate.

So it sends out an SOS.

It sends out a desperate SOS signal.

In response, the body jacks up the systemic blood pressure to try and force blood into the compressed brain.

The barrel receptors in the body detect this dangerously high blood pressure and say, Whoa, slow everything down.

So the heart rate drops, becoming bradycardic.

The pressure on the brain stem also affects the respiratory center.

So the triad is high blood pressure, low pulse, and an irregular or decreased respiration rate.

Exactly.

If you see that triad in a patient with a head injury,

the pressure in their head is critically high.

It's a sign of impending brain herniation and it is a dire emergency.

Let's talk about posturing.

Figure 23 .20 in the text shows this.

This is what you see when the brain is severely damaged and is being disconnected from the spinal cord.

We look for two specific involuntary positions in response to a painful stimulus.

They are decorticate and decerebrate posturing.

Let's start with the corticate.

To corticate.

Think core.

The arms are flexed tightly into the chest, into the core of the body.

The fists are clenched.

The legs are extended and internally rotated.

This indicates damage to the cerebral cortex, the higher thinking part of the brain.

And decerebrate.

Decerebrate is different.

The arms are extended stiffly down by the sides, the elbows are straight, and the hands are hyperpronated, twisted outward.

The legs are also stiffly extended.

This indicates damage that has reached the brain stem.

Which one is worse?

Decerebrate is generally considered a worse prognostic sign.

The brain stem controls your most basic life functions.

Breathing, heart rate, consciousness.

If the damage has progressed that deep into the brain, survival is much less likely.

The text mentions that the full neurological exam involves checking reflexes and all the cranial nerves.

There's a really helpful diagram of a clock face figure 23 .8.

The cranial nerve clock.

It's a great study tool for students.

It maps the 12 cranial nerves to where you would physically check for their function on the face and head.

So it's a practical guide.

It is.

For example, you can see the nerves 3, 4, and 6 are all about eye movement.

So simply by having a child follow your finger or a toy in all directions, you've just tested 3 nerves at once.

Nerve 7 is for facial movement, so you have them smile or puff out their cheeks.

Nerve 12 is the tongue, so you have them stick it out and move it side to side.

It helps you be systematic.

Let's move to section 4.

Congenital disorders.

We talk about how the neural tube is supposed to zip itself shut.

What happens when it doesn't?

That leads to spina bifida.

Spina bifida literally means divided spine.

It's a spectrum of defects where the vertebrae, the bony parts of the spine, don't close properly around the spinal cord during development.

The text describes two main types, occulta and cystica.

Right, occulta means hidden.

The bony defect is there, usually low down in the back at L5 or S1, but the spinal cord and its coverings are tucked safely inside the spinal canal.

Often, the only outward sign is a small dimple, a patch of dark hair, or a red spot on the skin over the area.

These kids are often asymptomatic.

But cystica is the visible one.

Cystical means there is a cyst, a visible sac protruding from the back, and this then splits into two important subcategories, meningoshell and meningomyosel.

Those are a mouthful.

Can you break them down?

Let's do it.

A meningoseli.

The sac that pokes out contains the meninges, which are the membranes that cover the spinal cord, and it contains cerebrospinal fluid.

But, and this is key, the spinal cord itself is still safely inside the spinal canal.

These kids often have normal leg function because the wiring isn't in the sac.

Okay, so that's the less severe of the two.

What about meningomyosel?

That's the most severe form of spina bifida.

The myelo part refers to the spinal cord.

In this case, the sac contains the membranes, the fluid, and the spinal cord nerves themselves.

The wiring has been pulled out of the spine and is now inside this fragile bubble on the baby's back.

Which means?

Which means there will be some degree of paralysis, loss of sensation, and bowel and bladder dysfunction below the level of the sac.

The nursing care for a newborn with that open sac on their back is incredibly specific and urgent.

It is the number one priority.

You have a very thin membrane separating the central nervous system from the outside world full of bacteria.

If that sac ruptures, bacteria get in, it causes meningitis, and it can be fatal.

So what are the steps to protect it?

First, positioning.

The baby is always positioned prone on their belly to keep all pressure off the sac, absolutely no holding them up against your chest.

Second, we cover the sac with a sterile dressing soaked in warm sterile saline to keep it from drying out, cracking, and leaking.

Long term, these kids face a lot of health challenges.

One is bladder management.

The text mentions something called the cre -day method.

Since the nerves that till the bladder when it's full and when to squeeze are often damaged, the bladder doesn't empty on its own.

It just fills and fills until it overflows, which can back urine up into the kidneys and cause damage.

The cre -day method involves the parent or caregiver applying gentle but firm manual pressure on the lower abdomen right over the bladder to physically push the urine out.

It becomes part of their daily routine.

There is also a fascinating and very specific allergy warning for patients with spina bifida, latex.

Yes, this is so important for nurses to know.

It's sometimes called the latex fruit syndrome.

Because these children have so many surgeries and urinary catheterizations starting from the day they are born, they have massive and repeated exposure to latex products.

And their bodies develop a sensitivity.

They develop a high rate of sensitization, leading to a true type I latex allergy.

But it's not just about rubber gloves and balloons.

There's a cross -reactivity.

What does that mean?

It means the protein structure in latex is very similar to the protein structures in certain foods.

The most common ones are bananas, avocados, and kiwis.

So if you have a patient with spina bifida, you have to create a latex -safe environment, but you also have to watch their diet.

An allergic reaction to an avocado could be just as severe as a reaction to a latex glove.

Let's start with meningitis.

Inflammation of the meninges, those membranes we just talked about.

This is a true pediatric emergency.

It has a peak incidence between 6 and 12 months of age.

The symptoms are classic, but can be hard to spot in an infant.

Nuchel rigidity.

A fancy way of saying stiff neck.

But let's explain why the neck gets stiff.

The meninges cover the brain and run all the way down the spinal cord.

When they are infected and inflamed, they are swollen and angry.

If you try to bend the child's head forward to touch their chin to their chest, you are physically stretching those inflamed tissues all the way down their back.

It causes excruciating pain.

So the child will instinctively resist any neck flexion.

And in severe cases, they do the opposite, right?

Opisotinos.

Yes, figure 23 .13 in the book shows this really well.

The baby involuntarily arches their back backward, creating a rigid C shape with their body.

They are trying to relieve the tension on the inflamed spinal cord by shortening the distance from head to tailbone.

It's a grave sign.

There is a specific rash associated with the most dangerous type, meningococcal meningitis.

Yes, a rash of patechia or purpura.

These are small purple or red dots.

They're actually tiny hemorrhages under the skin.

It happens because the bacterial toxins are damaging the blood vessels.

How do you tell them apart from a simple viral rash?

The tumbler test or the blanching test.

If you press a clear glass tumbler or even just your finger firmly on a normal rash, the skin underneath will turn white or blanch for a second.

Patechia do not blanch.

They stay red because the blood has already leaked out of the vessel.

If you see a non -blanching rash on a feverish child, that is a medical emergency.

Call for help immediately.

Section 6, structural defects and hydrocephalus.

Hydrocephalus.

The literal translation is water on the brain.

It's an imbalance between the production and the absorption of cerebrospinal fluid or CSF.

The text uses the analogy of a sink.

I find that helpful.

It's a perfect analogy.

You have a faucet, the choroid plexus in the brain, that is constantly dripping CSF into the brain's ventricles.

And you have a drain, the arachnoid villi, that is constantly absorbing it back into the bloodstream.

The system is usually in perfect balance.

But with hydrocephalus...

Either the drain is clogged, which is called non -communicating hydrocephalus, or the pipe just isn't absorbing the fluid properly, which is communicating hydrocephalus.

Either way, the sink overflows.

But the skull is a rigid box.

It can't expand,

usually.

In an adult or older child, no.

The pressure just builds and builds, which is life -threatening.

But in an infant, the fontanels, the soft spots, are still open, and the bony suture lines of the skull haven't fused yet.

So the head literally gets bigger.

It balloons out to accommodate all that extra fluid.

And this leads to some classic signs, like a rapidly increasing head circumference, bulging fontanels, and the setting sun eyes.

The setting sun sign is very dramatic.

The pressure inside the brain is so high that it physically pushes down on the part of the skull that forms the roof of the eye orbits.

This forces the eyeballs to look downwards, so you can see the white sclera above the pupil, making it look like the sun setting on the horizon.

The fix for this is essentially a plumbing bypass, a shunt.

The most common type is a ventricular peritoneal, or VP shunt.

A surgeon places a thin, flexible tube into one of the brain's ventricles.

That tube runs under the skin, behind the ear, down the neck and chest, and the end of it is placed into the peritoneal cavity, the belly.

The excess CSF drains harmlessly into the belly, where the body just reabsorbs it.

Section 7, seizure and epilepsy disorders.

This is a massive topic.

It is.

So first, let's get the terminology right.

A seizure is a single event, a sudden abnormal burst of electrical activity in the brain.

Epilepsy is a chronic neurological condition that is defined by having two or more unprovoked seizures.

The classification system for seizures changed in 2017.

Yes, so we're trying to move away from the old terms like grand mal and pity mal.

The new system focuses on where the seizure starts.

Focal onset means the electrical storm begins in one specific spot, or network, in one side of the brain.

Generalized onset means the abnormal activity starts on both sides of the brain at the same time.

Febrile seizures are the most common type of seizure in children.

And by far the most terrifying for parents to witness.

A previously healthy child gets a fever, and suddenly they are convulsing.

The key thing to understand is that it's caused by the rapidity of the temperature spike, not necessarily how high it gets.

It usually happens with a temperature over 38 .8 degrees Celsius.

The text has a specific warning against a common home remedy, sponge backs.

Yes, do not use tepid or cool sponge baths to bring down a fever.

It sounds logical, right?

Cool body down from the outside.

But the cool water on the skin makes the child shiver.

And shivering generates heat.

Shivering is a metabolic activity that generates heat.

So you are actually driving the core temperature up while you're cooling the skin.

It can make the seizure risk worse.

The correct approach is to give an antipyretic, like acetaminophen or ibuprofen, and remove excess layers of clothing.

No cold baths.

Let's review seizure first aid.

There are still so many myths out there.

The biggest one is, he's going to swallow his tongue.

Which is as possible, right?

Anatomically impossible.

Your tongue is anchored to the floor of your mouth.

The real danger is someone trying to help by putting a spoon, a wallet, or their fingers in the person's mouth.

You will break their teeth, or they will bite your finger to the bone.

Don't do it.

So what do you do?

The three S's.

Stay safe side.

Stay with the person.

Keep them safe by moving furniture away and cushioning their head.

And as soon as the convulsion stops, gently roll them onto their side into the recovery position so they don't choke on any saliva or vomit.

And time the seizure.

If it lasts longer than five minutes, you need to call 911.

We have to mention medication side effects.

The book lists many.

But phenytoin, which is dilanthine, causes something very specific in the mouth.

Gum hypertrophy or gingival hyperplasia.

The gums literally grow thick and puffy, sometimes covering the teeth.

It's cosmetically difficult for the child and can lead to serious dental disease.

Any child on phenytoin needs meticulous, aggressive oral hygiene brushing, flossing, and gum massage.

Finally, section eight.

Trauma.

Head injuries and submersion injuries.

Concussion management is a huge topic now.

The text emphasizes a really dangerous phenomenon called second impact syndrome.

This is why the when in doubt, set them out rule is so important in sports.

If a brain is still recovering and vulnerable from an initial concussion and it takes a second hit, even a seemingly mild one before it's fully healed, the brain's ability to regulate blood flow can fail catastrophically.

The brain swells massively and instantly.

It has a 50 % mortality rate.

It's rare, but it's devastating.

And submersion injury.

The terminology has changed here.

We don't say near drowning anymore.

No, the correct term is submersion injury.

The old term implied you either drowned, meaning you died, or you were near it and were fine.

The new term acknowledges that significant injury can happen to the lungs and brain, even if the person survives the initial event.

And the 24 -hour rule is the big nursing takeaway here.

It's absolutely critical.

A child falls in the pool, they're pulled out, they cough up some water, and within a few minutes, they seem totally fine.

The parents are relieved and want to take them home.

The answer from the nurse must be NO.

Why?

What's the risk?

It's called secondary drowning or delayed pulmonary edema.

The water that was aspirated into the lungs can wash away surfactant, which is the soapy coating that keeps the little air sacs open.

Hours later, those air sacs can start to collapse.

Fluid builds up, oxygen levels crash, and the child can go into severe respiratory distress.

They can die in their sleep hours after leaving the pool.

All submersion victims need at least 24 hours of close observation in a hospital.

That is a very sobering note to end on, but a potentially life -saving one.

And that's really the theme of this whole chapter, isn't it?

Whether it's spotting that subtle white reflex in the eye, or the non -blanching patechial rash, or understanding the risk of delayed drowning symptoms,

the observant, knowledgeable nurse is the safety net.

The learner definitely has a lot to think about.

We've covered the senses, the brain, the spine.

It's an incredibly complex system.

But I think understanding the why, the anatomy and the physiology

makes the what to do so much easier to remember.

If you know what normal development looks like, the abnormal just screams at you.

And that's our job, to hear it.

Thank you so much for joining us on this deep dive.

This was fantastic.

My pleasure.

It was a great conversation.

This has been a production of the Last Minute Lecture Team.

Thanks for listening.

Keep your eyes open and keep learning.