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Congenital Anterior Abdominal Wall Defects: Exomphalos and Gastroschisis 349

exstrophy, and anorectal anomaly are suggestive of a syndromic
omphalocele. When loops of bowel are eviscerated, it is important
to evaluate whether it is an omphalocele in which the membrane has
ruptured or the diagnosis should be a gastroschisis.
In gastroschisis (Figure 56.2), the eviscerate bowel segment is
commonly loops of small intestine and colon, sometimes stomach.
The umbilicus is attached to the normal site in an intact anterior
abdominal wall and the defect through which the bowel has herniated
is usually in the right side of the umbilicus, separated from it by a
small bridge of skin. There is no membrane over the bowel. A large
segment of bowel with oedematous and congested bowel wall is seen
in cases presenting late after birth. A bowel segment wholly covered
by fibrinous material—not an obvious membrane as in omphalocele—
suggests the gastroschisis had occurred early in utero. The fibrinous
cover is a result of reaction to amniotic fluid.
Investigations
A normal, generally healthy-looking baby in whom the only obvious
anomaly is the omphalocele needs immediate urgent exclusion of hypo-
Figure 56.1: Exomphalos major.
glycaemia before routine investigation of haemoglobin and electrolyte
checks are done. Other required investigations will be determined
by evidence of associated anomalies. Abdominal ultrasound is used
to ascertain the kidney, echocardiography is used if there are clinical
signs of cardiac anomalies, and x-ray of the chest is used if there are
signs relating to pulmonary anomalies. Chromosomal analysis may be
required to rule out trisomy.
Gastroschisis requires a haemoglobin and electrolytes check as for
preoperative preparation.
Treatment
Management of a baby with omphalocele or gastroschisis takes into
consideration the following:
• treatment and care of the general state of the baby;
• specific treatment of the omphalocele; and
• management of associated anomalies.
General Care
The neonate should be well wrapped up in warm clothing to prevent
hypothermia. Intravenous fluid should be commenced and the stomach
Figure 56.2: Gastroschisis.
should be kept decompressed with a nasogastric tube. The omphalo-
cele, or the eviscerated bowel in the case of gastroschisis, should be
well covered to reduce loss of heat and prevent injury. In intact ompha- Closure of Omphalocele Minor
locele, when there are no signs of intestinal obstruction or anorectal Primary closure
anomaly, the baby can be commenced on oral fluids and feed. The baby
Primary closure of the defect is possible in almost all cases of minor
should be transferred to a neonatal unit for further care.
omphalocele. The membrane is cleaned and excised. The edges of the
Nutrition in Omphalocele and Gastroschisis defect are determined and the fascial edges are closed, followed by
Small lesions may be expected to have no problem with normal feeds. skin closure.
When the baby vomits frequently in the early days of life, intestinal Delayed primary closure
obstruction should be suspected. Commonly, it is due to ileus and bowel
Primary closure may need to be delayed in minor omphalocele with
oedema. Atresia or malrotation are indications for early exploration.
an infected sac and oedematous abdominal wall. The sac is cleaned
Babies with gastroschisis have poor bowel motility due to the long
thoroughly, covered with Sofratulle and gauze, and then wrapped with
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exposure of the bowel loops to the amniotic fluid in utero; thus, delay in a soft crepe bandage. This is done daily, twice a day, morning and eve-
enteral feeding is frequently experienced. It is advisable to commence ning. If there is slough on the sac, the slough should be excised gently
parenteral nutrition where available and continue until the baby estab- without causing bleeding. After 6 or 7 days, the omphalocele may be
lishes normal gastrointestinal function.
closed by excising the sac and closing the fascia and the skin. When
Treatment of Omphalocele closing the skin, an attempt should be made to construct a navel.
The primary aim of treatment of omphalocele is to return the bowel Closure of Omphalocele Major
into the abdominal cavity and close the anterior abdominal wall. The Primary closure
possibility to do so will depend on whether the viscera can be placed in
the abdominal cavity without tension on the anterior abdominal wall, The abdominal cavity is closed with or without excision of the sac.
without intraabdominal compartment syndrome, and without pressure During primary closure, it is important to exclude intraabdominal
on the diaphragm, which would impair respiration. compartment syndrome, which is determined by poor urine output,
tight abdominal cavity, respiratory compromise due to splinting of the