Hypertrophic Pyloric Stenosis: Examination

00:01 How do babies present? Classically, they vomit postprandially.

00:06 The emesis is usually non-bilious.

00:09 And the emesis is described classically as projectile.

00:14 This makes anatomic sense.

00:16 As a pyloric channel becomes stenotic, gastric content has nowhere to go.

00:21 It’s non-bilious because it does not have the opportunity to mix with bilious content in the duodenum.

00:27 Projectile, because as a stomach gets more and more distended, it's got a closed channel by the pylorus.

00:33 The only way the patient can drain gastric content is by forceful vomiting.

00:40 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.

00:49 On physical examination, we oftentimes find an olive mass in the upper quadrant of the abdomen.

00:55 Because babies have relatively thin abdominal walls, this is easier to appreciate.

01:00 On the left side of the screen is a palpation of the abdomen, finding this olive mass.

01:06 And on the right side of the screen is an ultrasound.

01:09 We’ll get to that in a second.

01:11 Aside from a baby who may have projectile vomiting, they also have sunken fontanelles.

01:20 What does that mean? As you’ll remember, the skull has not completely fused in an infant.

01:25 And one of the first signs of dehydration is sunken fontanelles.

01:29 A lethargic baby.

01:33 This, obviously, is not specific to hypertrophic pyloric stenosis.

01:37 As you'll recall from many other pediatric modules, a lethargic baby or one that has failure to thrive is an ill baby.

01:45 There are some important findings on chemistry with patients with non-bilious projectile vomiting, such as in hypertrophic pyloric stenosis.

01:54 Low sodium, low chloride, and low bicarb.

01:59 The CBC may actually be completely normal.

02:02 Next, let's move to an ultrasound imaging.

02:06 Ultrasound imaging is first-line therapy.

02:08 Again, it doesn't introduce any radiation to the baby.

02:12 An ultrasound is particularly useful for pyloric channel stenosis.

02:16 Here in this image, you notice two white dots on the image.

02:20 It’s actually measuring the thickness of the channel.

02:23 Not only is the thickness important, the length of the channel is also important.