Let’s close by talking a
little about the pneumothorax.
So pneumothoraxes are
a collection of air
between the lung parenchyma and the
pleural lining on the chest wall.
They can be spontaneous
or they can be traumatic.
Let’s just pause for a moment
and think about lung mechanics.
When I take a breath in,
I expand my chest wall,
the air rushes in because I have a vacuum
between my lung parenchyma and chest
wall and those lungs now expand.
In a pneumothorax, a
hole has been created
either externally or internally
into that pleural space,
such when I breathe in, air can now accrue
between the lung and the chest wall.
So what are some congenital
causes of pneumothorax?
Well, the CCAM, or congenital
cystic adenomatous malformation,
can certainly erode
into that pleural space
and create a conduit for air
to get into our pleural space,
or a patient may have something
like congenital lobar emphysema,
where a piece of lung ruptures
open and then air can get in.
Alternatively, later in life,
asthma can cause a spontaneous
pneumothorax, as can bronchiolitis.
Both of these are obstructive
where children end
or having difficulty getting
the air out of the lungs,
and that hyperinflation can
result in microruptures
and air accrual in
the pleural space.
Likewise, foreign body
can do the same thing,
by acting as a ball valve and allowing
for a focal area of hyperinflation.
And, of course,
patients with cystic fibrosis are at risk
for pneumothorax for similar reasons.
In some patients with underlying
connective tissue diseases,
these patients may have
risk of pneumothorax
by virtue of the tissues themselves being
able to break apart a little bit more easily.
These are generally conditions where
there are problems in collagen.
Examples are Marfan syndrome
or Ehlers-Danlos syndrome.
Patients with these illnesses are at
increased risk for spontaneous pneumothorax.
Lastly, infections can
also cause pneumothorax.
So, a patient with a lung abscess, or a
pneumatocele, or a bronchopleural fistula,
these are all examples of where bacteria
have chewed through the lung tissue
and allowed a way for air to get down and
in between the lung and the chest wall.
So let’s talk about how
these patients present
and it really depends on the
size of the pneumothorax.
Patients with small pneumothoraces
are sometimes asymptomatic
and it’s simply found
incidentally on chest x-ray.
These often will resolve on their own and
don’t necessarily require any therapy.
Patients with large pneumothoraxes will
generally have a sudden onset pain,
especially with deep breath.
These patients do not want
to take a deep breath in
because those pleural surfaces
are exquisitely tender.
There’s one kind of pneumothorax that
shows up a lot on multiple choice tests,
which is the tension
This is the pneumothorax
in its most severe state.
If these patients will
have profound dyspnea
to the point perhaps of
altered mental status
or may even be in shock,
this is a huge pneumothorax that has
actually created increased pressure
on that side of the chest and is pushing
material, like the mediastinum,
over towards the other side.
How do we examine patients
and find pneumothoraces?
Well, small pneumothoraces typically
take up less than 20% of the lung field
and you really aren’t likely
to detect them on exam.
You’re not going to hear
anything or palpate anything
that’s going to
look any different.
In a large pneumothorax,
you will see the patient starts
having difficulty with breathing,
they may have hypoxia either from a lack
of inflation of that lung and V/Q mismatch
or through voluntary reduction in their
respiratory effort as a result of pain,
they may have an asymmetric chest rise,
especially if there’s trauma or some
piece of rib that’s not moving right.
This is also where you
see the flail chest,
which is where the chest is moving in a
different direction as they breathe.
In patients who have a large pneumothorax,
they will be hypertympanic to percussion.
Percussion is the lost
art of the lung exam.
Simply percussing on a
patient’s chest wall,
you’ll hear a hyperresonance
almost like that pneumothorax
is creating a drum.
Patients will have
decreased or diminished
breath sounds in the
area of the pneumothorax
because that air between the lung
and the chest wall is not moving
and, thus, you can can’t hear
breath sounds through it.
Tension pneumothorax is critical to
appreciate on physical exam because
the diagnosis is made
exclusively by physical exam
and the treatment is fairly severe
and needs to be done rapidly.
In these patients, they will
notice tracheal deviation
away from the side of the
The pneumothorax is creating increased
pressure and pushing that trachea over.
You’ll notice shifting of the apical
cardiac pulse away from the pneumothorax
or farther laterally if it’s on the right
side or medially if it’s on the left side.
These patients will have tachycardia
and hypotension from their
decreased venous return.
The blood is having a hard time
getting back into the chest
because the pressure
is so high there.
On an x-ray, you should be able to
make the diagnosis of a pneumothorax.
It’s a little bit embarrassing to get a chest
x-ray and diagnose a tension pneumothorax
because you should have made
that diagnosis on physical exam
and the x-ray was
delaying your therapy.
But in patients where you’re unsure, where
there’s not a tension pneumothorax,
the x-ray is the way to go.
Generally, we’ll take an upright because
it’s easier to see as air may layer up
if they’re supine and you won’t be able to
see a contrast between the air and the lung.
You’ll find the place where
there are no lung markings.
So there’s no lung markings,
no those fine little lines,
which are invading the area where
that pneumothorax is happening.
It’s pure air.
Small ones can be subtle.
Probably, many of you viewers have been
looking at this X-ray and thinking,
" I don’t see anything."
It can be a very subtle thing.
A tension pneumo is not subtle.
It would be a little bit inappropriate
to get a chest a x-ray, as I said,
because you’d be
But let’s look a little
closer at this x-ray.
So here’s a close up of the top of
this x-ray that I’ve been showing you
and maybe you’ve seen it
and maybe you don’t.
I’m going to draw a little
line for you right here.
That line, I’ll take it away,
now you can probably see it.
Do you see that area where
there’s that faint line?
Above that line, there
really are no lung findings.
None of those fine little lines,
but they are present below.
There’s the line.
Now it’s gone.
So, the diagnosis
Well, you’ve made the diagnosis,
you’ve said it’s either a small pneumothorax
or a large or a tension pneumothorax,
and now you want to know
what you’re going to do.
So in a small pneumothorax, such as
maybe that one in the last x-ray,
we’re not going to
do a whole lot.
We’re going to provide a hundred percent
oxygen by a non-rebreather mask.
This is complicated how this
helps, but it probably does.
A hundred percent oxygen by
mouth has no nitrogen in it.
When we breathe in, about
70% of our air is nitrogen.
Remember oncotic forces.
If we now breathe in a
hundred percent oxygen,
70% of the air in that
pneumothorax is actually nitrogen.
Now, in the blood, there’s less nitrogen.
So the nitrogen in this pocket will want
to be reabsorbed through osmotic forces.
Thus, a hundred percent oxygen
will allow that to shrink
and it probably will let it resolve sooner.
It’s nice especially to do this
in a patient who’s symptomatic.
But typically these will
resolve within in a week.
We’ll provide oxygen only as long
as it takes for them to feel better
in the in-patient
or the ER setting.
For a large or a
the indication is to immediately
decompress the lesion.
That means we have to get the air out.
It’s under great pressure.
So in a tension pneumothorax in particular,
we’re going to do that right away.
This is going to be an emergency
And then after that decompression,
we’ll put in a chest tube
and we’ll put that chest tube to suction
to allow that lung to remain inflated.
Now, that lung is going to gradually
heal up, the holes will be closed.
And when there’s no longer drainage of fluid
and there’s no longer adequate suction,
we’ll put it to water seal, and then
eventually remove the chest tube.
Rarely, the leak persists and that
requires surgery to repair the leak.
After patients are treated
we have to prevent recurrence.
So these patients in particular have some
First off, no smoking.
Really, no smoking.
Second, no deep sea diving.
Seems unusual, but those increased
pressures could cause that patient
to redevelop an acute
pneumothorax while underwater,
which has got to be the worst
place to have a pneumothorax.
And lastly, we need to be careful about
letting them fly in unpressurized planes.
Until they’ve truly healed up,
we worry that those could recur.
So let’s go through how to
decompress a tension pneumothorax,
this is high-yield
information on an exam.
Basically, you’ve got a patient who’s
coming in with a tension pneumothorax.
Let’s say, as in this case, the
patient has tracheal deviation,
the patient has absent
breath sounds on one side,
the patient has a shifted
apical pulse of the heart,
the patient is in respiratory
distress, or is hypotensive,
we need to fix this
So in this case, you’re going
to run into the next room
and get a large bore angiocatheter
or an IV 16, 18 gauge.
In this patient, we’re going to imagine
there’s a right-sided tension pneumothorax;
the trachea has deviated to the left,
the patient’s apex of the
heart is far lateral,
they’re in respiratory distress and shock.
We’re going to find the second
intercostal space in the ribs.
We’re then going to draw an imaginary
line down the midclavicular line.
So find the center of the
clavicle and draw a line right --
it’s a little bit past the
middle of the lung field.
Where those two things intersect,
you’re going to take that
large bore angiocatheter
and push it in and
remove the needle.
You should hear an immediate woosh of gas
as that highly pressurized air rushes out.
This patient should feel
much better very quickly.
Then, you’re going to have to go
about putting in a chest tube.
That’s all I have for you today
about this particular problem.
Thanks for listening.