Congenital abdominal wall defects

Omphalocele

• Incidence - 3 per 5,000

• M:F is 1.5:1

• >70% association with congenital anomalies such Bowel atresia, Imperforated anus, Trisomies 13, 18, 21, Beckwith-Wiedemann Syndrome & Pentalogy of Cantrell

• Congenital abdominal wall defect with protrusion of abdominal viscera contained within a parietal peritoneum and amniotic membranous sac with Wharton’s jelly.

• Due to failure of the midgut to return to abdomen by the 10th week of gestation during midgut rotation.

• Increased maternal age

• Twins

• High gravida

• Consecutive children

• central defect of the abdominal wall beneath the umbilical ring.

• Defect may be 2-12 cm (Small-<5cm)(Large>8cm)

• Always covered by sac

• Sac is made of amnion, Wharton’s jelly and peritoneum

• The umbilical cord inserts directly into the sac in an apical or lateral position.

• Small contains intestinal loops only. Large may involve liver, spleen and bladder, testes/ovary

• >50% have associated anomalies

• Umbilical cord insertion is typically midline on the mass

• Located centrally

• Contents are intestinal loops and maybe liver, spleen and gonads.

Conservative

1. Large omphalocele (10-12cm) apply topical application - Betadine ointment or silver sulfadiazine to the intact sac.

2. Secondary eschar formation and granulation.

3. Healing lasts for 12 months then repaired as ventral hernia.

Primary Closure

• Small defects (<4cm)

• excision of the sac and closure of the fascia and skin over the abdominal contents

Mesh patch - Medium defects (6-8cm)

Small - recover well

Large:

• Gastro-oesophageal reflux - 43%

• Majority improve over time

• 20% pulmonary insufficiency

• Respiratory Infections

• Asthma

• Feeding difficulties;

  • 60% with giant omphalocele

  • May need gastrostomy for feeding

• Failure to thrive