In this lecture, we’re going
to discuss pulmonary diseases
that show up in older children.
Now, we’re going to exclude cystic
fibrosis, which has its own lecture,
and we’re excluding pulmonary
diseases that show up in infants,
which also has its own lecture.
This is really other problems in children.
Let’s start off with
So a pulmonary embolism can happen, but
it’s very in children compared to adults.
It is seen more commonly in
diseases or circumstances
where there’s a predisposition
to forming a clot
and the mortality rate is
only 20% that of adults.
In other words, children are more likely
to have smaller pulmonary embolisms
and they’re more likely to survive
the event and live past it.
So in order to understand the
pathophysiology of the pulmonary embolism,
we have to recall
the three things that are
resulting in a clot inside a blood vessel.
One is stasis,
one is the
and the other is
And we have these three things,
we’re at increased risk for creating
a thrombus inside the child.
That thrombus can then proceed
up and into the lungs,
where it causes the
One way to remember
it is I's and O's.
So there are Is and Os that are responsible
for causing pulmonary embolism.
The I's are indwelling
or inherited disorders
Remember, in kids,
they present with unusual congenital
problems more often than adults do,
so these inherited disorders are
something we will absolutely think of
in a child who presents
with a pulmonary embolism.
The O's: obesity, oral contraceptive
pills, or orthopedic surgery,
which is really more of the immobilization,
but a nice way to remember that.
So in terms of the
pathology of the disease,
most pulmonary embolisms start as a thrombus
in a vein, and then fly into the lungs.
This is usually starting
off in a lower extremity
but can be in the upper extremity,
the pelvis, the kidney,
or even just the right
side of the heart.
And as we say it before, these are rare,
but even rarer still are air emboli,
tumor emboli, or fat emboli,
which can cause similar symptoms,
but aren’t necessarily from a clot.
So the pulmonary embolus, if
it’s rare, how do we suspect it?
These patients will typically have a history
of sudden onset pleuritic chest pain.
They’ll have difficulty of
breathing that is sudden onset.
About 50% of them
will have a cough
and about a third of them
will have hemoptysis.
Hemoptysis in a child
is never normal.
If they’re presenting with a
massive pulmonary embolism,
which is exceptionally rare and
much rarer than in adults,
these patients will have a sudden onset
cyanosis and right ventricular failure.
These are the patients with
jugular venous distention,
hepatomegaly, they may have a single
loud S2, other problems like that.
The majority of children presenting
with a pulmonary embolism
though are going to
be non-massive PEs.
About half of these children
will have tachypnea,
they will often
and you may auscultate.
While you’re examining them, you
may hear crackles, wheezing,
or usually they’re just
clear to auscultation.
So as you can see, a lot of these
symptoms are somewhat nonspecific
and in children it’s
a rare condition,
so you can imagine this is a challenging
diagnosis to make, and it is.
One test that’s particularly helpful and
important to know about is the D-dimer.
This is very important.
A positive D-dimer does not
confirm a pulmonary embolism.
The D-dimer is an acute phase reactant
that can be elevated by almost anything.
However, it’s almost unheard of to have a
pulmonary embolism have a normal D-dimer.
So we routinely get the D-dimer as a
way of ruling out pulmonary embolism.
If I have a patient with
chest pain and tachypnea
and I’m thinking maybe
it’s a pulmonary embolism
because the girl takes
oral contraceptive pills,
but I get a normal D-dimer, I usually
won’t pursue this any further.
Other testing that’s
important can be an ABG,
which may show V/Q mismatch in the
lung as a result of that clot.
A chest x-ray may show
an area of collapse.
But, really, the most important
test for truly ruling out
a pulmonary embolism is the spiral CT.
Now, we do like to avoid
radiation in children.
Remember, children are probably
at more risk for cancer
as a result of radiation exposure simply
because there’s more mitosis going on
and more opportunity for
negatively impacting mitosis.
But the spiral CT
is the way to go.
In the books, there will
be mentions of V/Q scans;
however, their accuracy at
predicting pulmonary embolism
is really no better
than the spiral CT.
Also, you may read about angiography as the
gold standard and this is absolutely true.
It is the gold standard,
but really is very seldom used.
The reason being
spiral CT is very good
and angiography confers actually
quite a bit of radiation.