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292 Congenital Diaphragmatic Hernia and Diaphragmatic Eventration

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for foetal surgery is being questioned in recent studies, however. Foetal
surgery for CDH is being assessed in specialist centres, but as yet, there
are no clear indications and benefit from this approach. 2,3
Postnatal
Postnatally, the infant presents with respiratory distress. The timing of
presentation is proportional to the degree of respiratory reserve; the
later the presentation, the better the reserve and the baby’s outcome.
Grunting, tachypneoa, cyanosis, and poor feeding may be present.
Physical examination
A general physical examination may reveal respiratory distress with
grunting, use of accessory muscles and cyanosis. The affected hemi-
thorax will have decreased respiratory movement. The trachea and
apex beat may be deviated to the contralateral side. Diminished breath
sounds with audible bowel sounds may be heard in the affected side.
The abdomen is generally scaphoid in those presenting early. If presen-
tation is delayed, however, this sign may not be present.
One particular presentation of CDH is with the constellation of the
five malformations making up the pentalogy of Cantrell, a rare defect
resulting from a severe mesodermal fusion failure:
Figure 45.2: Chest x-ray showing a left CDH. Bowel loops are seen in the chest,
1. Diaphragmatic hernia;
and there is mediastinal shift. The appearances could be similar to congenital
2. Lower sternal defect; lung cysts, and an abdominal x-ray is needed to confirm the diagnosis.
3. Pericardial defect;
4. Major cardiac anomaly; and
5. Epigastric exomphalos.
Late and atypical presentations
In the absence of antenatal scanning and the absence of neonatal symp-
toms, some children may present later in childhood. They may present
with poor feeding or vomiting and failure to thrive, poor respiratory
reserve to strenuous exercise, or almost incidentally on an x-ray for a
suspected chest infection. Subtle respiratory signs may be noted.
Cases are reported of children subject to minimal trauma, with
severe respiratory symptoms, who undergo a chest x-ray and a
diagnosis of tension pneumothorax is made (mistaking the herniated
stomach for air in the pleural space). Needle or tube thoracocentesis
of the chest is an avoidable iatrogenic complication if the x-ray is
scrutinised carefully and the absence of a diaphragm noted, confirming
a diaphragmatic hernia. Most of these cases are found to be a CDH
at operation, although a traumatic rupture of the diaphragm is an
alternative diagnosis.
Differential diagnosis
The main differential diagnosis and the key features in differentiating
them are:
• Eventration of the diaphragm: A thin rim of soft tissue shadowing
may appear on the chest x-ray, suggesting that some diaphragmatic
tissue is present. The diagnosis is best distinguished by using fluo-
roscopy to demonstrate paradoxical chest movement during respira- Figure 45.3: Abdominal x-ray of the same patient as in Figure 45.2. Bowel loops
tion, but the distinction is sometimes made only at operation. are seen in the chest, and there is paucity of gas in the abdomen, confirming
herniation. In this patient, the stomach did not herniate; therefore, the NGT is in
• Congenital pulmonary airway malformations: Congenital malfor- the abdomen.
mations of the airway and lung with cysts in the lower chest can
mimic CDH on a plain x-ray of the chest. In these cases, however, • absence of the diaphragm;
the abdominal x-ray demonstrates a normal gas pattern with the
nasogastric tube (NGT) in the abdomen, and a good diaphragmatic • bowel loops seen in the chest, with paucity of loops in the abdomen;
rim is usually seen. Usually no further imaging is needed to dif- • tip of NGT in the chest (only if stomach is herniated);
ferentiate them, but a computed tomography (CT) scan is helpful
in difficult cases. • mediastinal shift; or
Investigations • with right-sided lesions, a radio-opaque lesion replaces the lung tissue.
A plain anterior-posterior radiograph of the chest is diagnostic in most With a Morgagni hernia (see Figure 45.5) the features include a
cases. The x-ray should be combined with a plain abdominal x-ray with radiolucent shadow overlying the heart. A lateral view is helpful in
a nasogastric tube in place. Features of the common Bochdaleck hernia showing this to be in the anterior mediastinum.
on the radiograph are (see Figures 45.2–45.4):