Approach to abdominal wall defects: Clinical sciences

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Introduction 0:00–0:34

An abdominal wall defect refers to an abdominal organs such as the intestines, protrude through a weakness or opening in the abdomen.
These are typically congenital and present with a wide variety of clinical findings. Patients may present as unstable with abdominal viscera outside of their abdominal cavity or stable with findings ranging from a generalized decrease of abdominal muscle tone to a localized inguinal or umbilical mass.
Now, if a pediatric patient presents with an abdominal wall defect, perform an ABCD E assessment to determine if they are stable or unstable.

Unstable0:34–1:51

If unstable, stabilize the airway breathing and circulation. Next, obtain IV access and consider starting IV fluids and antibiotics.
Then place your patient on continuous vital sign monitoring and provide supplemental oxygen if needed. Consider placing a nasogastric or orogastric tube to empty the stomach.
Finally cover any protruding abdominal viscera with a warm moist sterile gauze or bowel bag to decrease the risk of necrosis infection and evaporative fluid losses.
Once you have initiated acute management, obtain a focused history and physical examination history might include prenatal testing showing an elevated alpha fetoprotein level and a prenatal ultrasound revealing an abdominal wall defect with viscera outside of the abdominal cavity as far as the newborn physical exam goes, youll notice visceral herniation through a skin defect in the abdomen.
These findings should make you consider gastroschisis and omphalocele. Proceed with your evaluation by assessing the viscera for a membrane covering.
If a membrane is absent, consider gastroschisis. In this case, history might include risk factors such as a teenage birthing parent or antenatal use of tobacco, drugs like opioids and cocaine or decongestants.

Gastroschisis 1:51–2:36

The physical exam will reveal that the defect is to the right of the midline and umbellatus and that the herniation contains bowel, usually small intestine intestinal atresia may also be present at this point.
Diagnose gastroschisis. Here's a clinical pearl.
The most common complication of gastroschisis is gastrointestinal dysmotility. This occurs because without a protective membrane, the bowel is exposed to amniotic fluid during pregnancy.
On the other hand, if you identify that the viscera are covered by a membrane consisting of peritoneum, Wharton's jelly and amnion consider omphalocele.

Omphalocele 2:36–3:31

In this case, history may reveal other congenital defects including cardiac genitourinary or neural tube defects. There is often an associated genetic disorder such as Trisomy 1318 or 21 or Beckwith Wiedemann syndrome.
Meanwhile, the physical exam will reveal that the defect is midline and that the hernia sac contains small bowel and possibly stomach colon, bladder or liver.
At this point, you can diagnose omphalocele. Here's a high yield fact, other much less common full thickness defects of the abdominal wall include bladder exstrophy, cloacal exstrophy and limb body wall syndrome, which is fatal and involves multiple organ systems.
Ok. Now that we've considered unstable patients, let's return to the ABCD E assessment and discuss stable patients begin with the focused history and physical examination history might reveal a mass or bulge that changes with valsalva.

Stable 3:31–4:02

The physical exam might include a skin fascia or muscle defect, an abdominal or inguinal mass or umbilical discharge. With these findings, consider an abdominal wall defect and assess the abdominal muscle tone and skin.
If you find decreased muscle tone and wrinkled skin, consider prune belly syndrome. Here, most patients are biological males.

Prune belly syndrome 4:02–5:31

If a prenatal ultrasound was performed, youll see a history of oligohydramnios, bladder distension and ureteral or kidney dilatation, renal dysplasia and bladder outlet obstruction can cause varying degrees of prenatal oligohydramnios that may result in pulmonary hypoplasia.
There might also be history of cardiac and skeletal anomalies on physical exam. Youll appreciate absent or lax abdominal musculature, a distended palpable bladder and undistended testes.
Your next step is to obtain a chest and abdominal x-ray, voiding cystourethrogram and echocardiogram. The x-ray will demonstrate a bell shaped thorax and abdomen while voiding cystourethrogram will show ureteral reflux and dilatation.
A distended bladder and renal dysplasia or dilation. The echocardiogram might reveal an atrial or ventricular septal defect or evidence of tetrology of fallot.
At this point. You can diagnose prune belly syndrome, also known as Eagle Barrett Syndrome or Triad Syndrome here's another clinical pearl.
The characteristic triad for prune belly syndrome consists of the absent abdominal muscles, urinary tract malformation and undescended testes.
You appreciated on physical exam and imaging. Ok.
Now, let's move on to patients with normal abdominal muscle, tone and skin. Here.

Inguinal hernia 5:31–7:20

Your next step is to assess for an inguinal or umbilical mass. If there is an inguinal mass present, consider an inguinal hernia which can contain bowel omentum or an ovary.
In this case, the history will include a bulge that enlarges with coughing, straining or crying. The physical exam will reveal a mass in the inguinal canal, scrotum or labia majora that reduces spontaneously or with gentle pressure.
Keep in mind that an irreducible hernia is an emergency. This is known as an incarcerated hernia and is at risk for strangulation, which is when ischemia occurs and possibly necrosis on physical exam.
You might also find a thickened spermatic cord or the silk glove sign, which refers to when the layers of the hernia sac slide over the spermatic cord and feel like the layers of a silk glove.
With these findings diagnose inguinal hernia. Here's a high yield fact, inguinal hernias are classified as indirect, direct or femoral in Children.
Most inguinal hernias are indirect and congenital meaning they are present at birth. If the process vaginalis remains patent, it allows for the viscera to travel through the internal inguinal ring and originate laterally to the inferior epigastric vessels.
On the other hand, direct hernias are acquired and due to a weakness in the abdominal wall muscles, they protrude directly through the posterior wall of the inguinal canal and originate medially to the deep inferior epigastric vessels.
Finally, femoral hernias are uncommon in Children. They protrude through the femoral ring and are inferior to the inguinal ligament and medial to the femoral vessels.
All right. If an umbilical mass is present, your next step is to assess for umbilical drainage.

Umbilical hernia 7:20–8:14

If there is no evidence of umbilical drainage, consider an umbilical hernia, the history will include an umbilical swelling that enlarges with coughing, straining or crying.
And there is often a family history of umbilical hernias. The physical exam will demonstrate an easily reducible soft swelling at the umbilicus and possibly diastasis recti with these findings diagnose umbilical hernia time for a clinical pearl.
A common umbilical abnormality seen in the newborn is an umbilical granuloma. However, it is not a defect in the abdominal wall.
It consists of granulation tissue that persists after the umbilical cord separates and often presents as a small red mass with serosanguinous drainage.
Now, if umbilical drainage is present, you should assess the quality of the drainage. If the drainage is urine, consider a patent urachus, the history might include umbilical infections while the physical exam might reveal an umbilical granuloma or inflammation at this point, obtain an abdominal ultrasound.

Patent urachus 8:14–9:12

And if it demonstrates a fistula tract or tubular structure connecting the bladder to the umbilicus, diagnose patent urachus.
Here's a final clinical pearl. During embryonic development, the urachus connects the bladder to the umbilicus.
It normally narrows obliterates and becomes a thick fibrous cord called the median umbilical ligament. A patent urachus is present if it does not obliterate and a fistulous tract between the bladder and umbilicus remains.
These patients may have additional urinary abnormalities like bladder outlet obstruction. It is also often found in patients with prune belly syndrome.
Finally, if there is feculent brown drainage at the umbilicus, consider an omphalomesenteric fistula. The history will include a meconium stained umbilicus and possibly recurrent umbilical infections.

Omphalomesenteric fistula 9:12–10:08

While the physical exam might show umbilical inflammation as your next step, perform an abdominal ultrasound and look for a tubular structure connecting the ileum to the umbilicus.
If present, diagnose an umph ballo mesenteric fistula. And here's your last high yield fact.
Early in fetal development, the omphalomesenteric duct connects the gut to the yolk sac. Normally it's resorbed when the placenta forms and provides nutrients to the fetus.
If it does not resorb, several anomalies can occur including omphalomesenteric fistula, meckels, diverticulum fibrous bands, cysts and umbilical polyps.
All right, as a quick recap when evaluating an unstable patient with an abdominal wall defect, provide acute management and assess for a membrane covering the protruding viscera.

Review 10:08–10:44

An absent membrane suggests gastroschisis while the presence of a membrane suggests omphalocele. In stable patients with decreased muscle tone and wrinkled skin of the abdominal wall, consider prune belly syndrome.
On the other hand, when you palpate an inguinal mass, think of an inguinal hernia. But when you appreciate an umbilical mass, consider an umbilical hernia patent urachus or an omphalomesenteric fistula.