Cervical Spine Protection in Airway Management (not a substitute for formal training)

DR. MAHADEVAN: Hi,
this is Dr. Mahadevan

of Stanford University
School of Medicine.

I'm here with my good friend--

SAL KHAN: Sal.

DR. MAHADEVAN: --Sal Khan.

And we're following up to
our earlier discussions

about cervical spine
injuries, or neck injuries.

And we're going
to talk about some

of things you might do to
manage a patient who might have

a cervical spine
injury in the case

that you had to do
something invasive,

like manage their airway.

SAL KHAN: Right.

When you say manage
their airway,

there might be something
stuck in their airway,

or blocking their airway.

DR. MAHADEVAN: Usually
the tongue falls back

and blocks the airway.

But you're right.

If your airways blocked, you
can't get air to your lungs.

And if you can't get air
to your lungs, you die.

SAL KHAN: Right.

And when you said, usually
your tongue falls back,

that's normal-- wait, what
are you talking about?

DR. MAHADEVAN: When
you're unconscious,

the musculature, or the muscles
that control your tongue,

relax.

Because you're unconscious,
your tongue falls back exactly.

And it falls back into
your pharynx, which

is a posterior part
of your throat, there,

and that blocks the air
from either going either

through your mouth or your
nose into your trachea,

and then into your lungs.

SAL KHAN: Really?

So if someone's
just unconscious,

and they fall back
like that, that

might cause them
to stop breathing?

DR. MAHADEVAN: That would
obstruct their ability

to breathe, and so even if
they were trying to breathe,

they wouldn't be able to move
as much air into their lungs.

SAL KHAN: OK.

So it could be
literally something

as simple as moving the
tongue out of the way.

DR. MAHADEVAN: Exactly.

And that's really what these
first two diagrams show.

The one with the
young boy, there,

is showing a technique called
the head tilt-chin lift.

SAL KHAN: Head tilt.

OK, so he's laying down,
they're pushing on his-- OK,

they're pushing on that hand,
down on the top of his head,

and then lifting up there.

DR. MAHADEVAN: Exactly.

And in doing so, in
sort of tilting the head

and pulling the chin up,
what you're effectively doing

is pulling that
tongue out of the way,

and opening the airway so
air can get into your lungs.

SAL KHAN: I see.

And this is a little
off topic, but where

did you get these pictures?

DR. MAHADEVAN:
These are actually

pictures of my children.

SAL KHAN: Yeah, I
thought he was joking,

because they're
clearly drawings.

I thought he lived in some
type of animated reality.

But no, apparently
they are your children.

DR. MAHADEVAN: That's my son,
[? Auditya, ?] on the left,

and my daughter,
[? Lavinya, ?] on the right.

SAL KHAN: OK, so someone
traced them afterwards.

They aren't--

DR. MAHADEVAN: Absolutely,
a very excellent

medical illustrator
changed them from pictures

into illustrations.

SAL KHAN: Very cool.

So sorry, that was off topic.

DR. MAHADEVAN: And so
the head tilt-chin lift.

But as we talked about earlier,
if you had a spine injury,

moving the neck, or
tilting the head,

could potentially
cause an injury.

And so in trauma
victims, we tend

to avoid using this
particular technique.

And we use the one
there on the right.

SAL KHAN: I see, I see.

Because something
might have happened

to their spine or their neck.

DR. MAHADEVAN: And the
last thing you want to do

is turn their neck, or
flex or extend their neck.

SAL KHAN: I see.

Right, because this is going
to put a little pressure

on the neck around that area.

DR. MAHADEVAN: Exactly.

Exactly.

And the bones can move,
and if the bones move,

they can injure the spinal cord.

SAL KHAN: This is, whoever this
person who's hands these are--

DR. MAHADEVAN: My wife's hands.

SAL KHAN: Oh, these
are your wife's hands?

Really?

It's a family affair.

And so what is it
she doing exactly?

DR. MAHADEVAN: She's
doing a maneuver which

we would use in someone
who potentially could have

an injury to the neck,
called the jaw thrust.

And essentially
what she's doing is,

she's grasping the angle of the
mandible, exactly right there,

kind of like a little 90
degree angle that we have,

and pulling that
mandible forward.

And in doing that,
what she's doing is,

she's doing the same thing
as the head tilt-chin lift,

just she's not flexing the
neck or extending the neck.

SAL KHAN: So you're just kind of
just moving the jaw as opposed

to everything else.

DR. MAHADEVAN: And
in moving the jaw,

you're pulling that
tongue forward,

and opening the airway.

SAL KHAN: I see, because
the tongue's in there.

OK.

That makes sense.

DR. MAHADEVAN: And so
this is the technique

that we use for trauma victims.

And the reason that
this is important

is really shown in the x-rays.

And what you see
is, the same person.

And in the first
x-ray, you can see,

as we talked about earlier,
their spine is well aligned.

So if you were to
check their alignment,

anterior vertebral body line--

SAL KHAN: Yeah, I'm an
expert at this, now.

DR. MAHADEVAN: --posterior
vertebral body line,

spinolaminar line, and
spinous process line

all look fine in this
particular circumstance.

But what you can see, is
if you remove the lines,

you can see that there
is a small fracture--

SAL KHAN: Right here.

DR. MAHADEVAN: --right there.

Exactly.

And right in front
of that fracture,

there's a bunch of swelling.

All that stuff right there
is your soft tissues,

and so they're swollen.

And what you can't see is
that your whole cervical spine

is held together by ligaments.

And sometimes they can
be torn, and you may not

be able to see
them on the x-ray.

SAL KHAN: I see.

How did you know there
was swelling here?

DR. MAHADEVAN: If you
look at the x-ray,

you can see that the distance
between the front of the spine,

and the front of the
soft tissues, is widened.

SAL KHAN: Than what
you would normally see.

DR. MAHADEVAN: Exactly.

SAL KHAN: I see

DR. MAHADEVAN: Exactly.

It's usually very
small, very narrow

in that part of
the cervical spine.

SAL KHAN: I see.

It makes sense.

DR. MAHADEVAN: And
what you realize

is, if a person were to come
and try to open the airway,

what happens on the next
radiograph could occur.

So if I were to--

SAL KHAN: So if they used this
technique right over here.

DR. MAHADEVAN: Exactly if they
were to use the head tilt-chin

lift, and were to
tilt that head back--

SAL KHAN: Oh, yeah, put
that pressure right there.

DR. MAHADEVAN: Exactly.

What could happen,
the next x-ray shows--

SAL KHAN: They push the--
I wanted to use magenta,

It's easier to see.

So they push that back--

DR. MAHADEVAN: Exactly.

SAL KHAN: And then
[? wow. ?] OK.

DR. MAHADEVAN: And now if you
were to draw your lines again,

specifically, the anterior
you might get away with--

SAL KHAN: Yeah, but
this one right--

[INTERPOSING VOICES]

DR. MAHADEVAN: Definitley the
posterior line is abnormal.

And again, the key fact
here is that, right

behind that line that you
drew is your spinal cord.

SAL KHAN: Yes,
which is important.

Right.

DR. MAHADEVAN: And so one of the
tenets of Emergency Medicine,

and medicine in
general, is do no harm.

And here, in an attempt to
open the air way, by this head

tilt-chin lift
maneuver, we potentially

could do harm to the patient.

SAL KHAN: Yes.

Wow, wow.

Do no harm.

It's a good first rule of thumb.

Right, right.

DR. MAHADEVAN: The next
step that we would take,

if just simply
opening the airway

wasn't adequate to get
someone breathing again,

potentially would be to actually
intubate them, or insert

a plastic breathing
tube into their trachea,

and allow them to breathe.

What you can see there
is the act of intubation.

SAL KHAN: So yeah, I've heard
this word intubate a lot.

My wife is a
physician, and I always

hear-- so this is
literally you're

inserting a tube
to clear things?

DR. MAHADEVAN: You're
inserting a tube

to create a passageway from
the oxygen-rich atmosphere,

and directly into your lungs.

And again, if your
tongue has fallen back,

and you can't keep it out
of the way, or you vomited

and you're
unconscious, this would

be something that
would help you breathe.

SAL KHAN: How far
does this tube go?

DR. MAHADEVAN: It starts
right at your mouth,

and it goes all the way down--

SAL KHAN: It's a flexible
tube, I'm assuming.

DR. MAHADEVAN: It's
a flexible tube,

and it would go right in between
this cartilage right here.

So it would kind of go
right there, exactly.

Right through the larynx,
and right there where

you've got the pointer, there,
is where your vocal cords are.

And it would go just
beyond the vocal cords,

right into your trachea.

SAL KHAN: I see.

DR. MAHADEVAN: Exactly, exactly.

SAL KHAN: And that's
because that's

where you normally have
something blocking.

DR. MAHADEVAN: That is
the connection between

the oxygen-rich environment--

SAL KHAN: Oh, yeah.

After that, then
the oxygen can get

to you, at least some
part of your lungs.

DR. MAHADEVAN: You've
got a tube now.

You've got an airway, and
you can give, deliver oxygen

to a patient through that tube.

SAL KHAN: I see.

I see.

And what are they doing here?

What are they pinching?

DR. MAHADEVAN: In this
particular diagram,

what they're doing
is a couple things.

There's actually
three people there.

One person who looks
like they're pinching

is actually putting
pressure on your cartilage,

your cricoid cartilage.

And they're doing that
to push back and occlude

your esophagus.

SAL KHAN: Occlude the esophagus.

What is occlude?

DR. MAHADEVAN: They want
to close off the esophagus

because the esophagus
connects to the stomach.

The stomach is full of
whatever you had to eat.

SAL KHAN: Oh, I see.

So you might be continuing
to-- fluid could be coming out

and all of that.

I see.

So there could be stuff
coming out from the stomach.

DR. MAHADEVAN:
Right and that tube.

The esophagus runs right back
here, and it could come up.

SAL KHAN: Sorry.

Shows how much I know
about [INAUDIBLE].

DR. MAHADEVAN: Exactly.

Running right behind
your airway, right there,

and by pushing back, you
collapse the esophagus

and prevent any of what we
call passive regurgitation or--

SAL KHAN: I see.

So they're pushing this--
and let me do this in another

color-- they're
actually pushing back,

and the esophagus is likely
to get closed, then--

DR. MAHADEVAN: Exactly.

SAL KHAN: So something
can't come from the stomach.

That doesn't close-- the
trachea's more rigid?

DR. MAHADEVAN: The trachea
is a rigid structure.

And this is actually, the
first ring of the trachea

is a cricoid
cartilage, and that's

what they're pushing
on right there.

SAL KHAN: I see.

So this is rigid there,
so when you push,

it closes the esophagus,
trachea can still stay open.

DR. MAHADEVAN: Exactly.

SAL KHAN: That makes sense.

DR. MAHADEVAN: Exactly.

So there's three people.

One person that we talked about
is giving cricoid pressure,

and that would be that gentleman
right there, or a young lady.

The second person is
actually holding the head,

as you can see.

And the reason that
they're doing that

is for what we showed earlier.

They don't want that
head to extend or flex.

So they're actually holding the
person in the neutral position

to prevent those bones,
potentially, from moving.

SAL KHAN: Right,
because they're going

to be jiggling
this thing through,

and if there wasn't
someone holding it,

it could do that same damage.

DR. MAHADEVAN: Absolutely.

[INTERPOSING VOICES]

DR. MAHADEVAN: And when you're
that guy at the top who's

trying to see the vocal
cords, and pass the tube,

you don't care
about anything else

except for seeing
the vocal cords.

So you might inadvertently flex
the neck or extend the neck.

SAL KHAN: Right,
that makes sense.

It makes sense.

Is that also why they
say at an accident,

no, don't move the person
and that type of thing?

DR. MAHADEVAN:
That's exactly why.

Again, do no harm.

In trying to help the
person by lifting them up,

or tilting their head,
or flexing their neck,

you potentially could cause a--

SAL KHAN: And that's why wait
for the EMTs, or whoever,

and then they'll--

DR. MAHADEVAN: Absolutely.

SAL KHAN: --do it right.

I see.

DR. MAHADEVAN: And if you
really had to open their airway,

you could use the
jaw thrust maneuver.

SAL KHAN: Right.

Just pull their jaw forward.

DR. MAHADEVAN: Exactly.

SAL KHAN: And hold on to the--

DR. MAHADEVAN: Exactly.

SAL KHAN: We touched
on right before this,

there's other ways
of doing this?

Or there's other methods
that people talk about?

DR. MAHADEVAN: This
cricoid pressure

is quite controversial,
because one of the things

is it's supposed to help
you with this procedure,

and some people feel that it
may not be proven to help you.

Or it potentially
can cause injury.

But for those of
us that are older,

have used this technique for a
long time, still stand by it.

SAL KHAN: OK, this is what y'all
teach it at the med school.

DR. MAHADEVAN: Exactly.

SAL KHAN: OK.

DR. MAHADEVAN: Exactly.

SAL KHAN: Well, thank you.

This is very, very useful.

DR. MAHADEVAN: You bet.