How do babies present?
Classically, they vomit postprandially.
The emesis is usually non-bilious.
And the emesis is described classically as projectile.
This makes anatomic sense.
As a pyloric channel becomes stenotic,
gastric content has nowhere to go.
because it does not have the opportunity
to mix with bilious content in the duodenum.
as a stomach gets more and more distended,
it's got a closed channel by the pylorus.
The only way the patient can drain gastric content
is by forceful vomiting.
One important thing to notice is how the child is always hungry after vomiting and wants to feed again,
a sign called the hungry vomiter.
On physical examination,
we oftentimes find an olive mass in the upper quadrant of the abdomen.
Because babies have relatively thin abdominal walls, this is easier to appreciate.
On the left side of the screen is a palpation of the abdomen,
finding this olive mass.
And on the right side of the screen is an ultrasound.
We’ll get to that in a second.
Aside from a baby who may have projectile vomiting,
they also have sunken fontanelles.
What does that mean?
As you’ll remember,
the skull has not completely fused in an infant.
And one of the first signs of dehydration is sunken fontanelles.
A lethargic baby.
This, obviously, is not specific to
hypertrophic pyloric stenosis.
As you'll recall from many other pediatric modules,
a lethargic baby
or one that has failure to thrive
is an ill baby.
There are some important findings on chemistry
with patients with non-bilious projectile vomiting,
such as in hypertrophic pyloric stenosis.
and low bicarb.
The CBC may actually be completely normal.
Next, let's move to an ultrasound imaging.
Ultrasound imaging is first-line therapy.
Again, it doesn't introduce any radiation to the baby.
An ultrasound is particularly useful for pyloric channel stenosis.
Here in this image,
you notice two white dots on the image.
It’s actually measuring the thickness of the channel.
Not only is the thickness important,
the length of the channel is also important.