Gastroschisis

An infant born to a 25-year-old gravida 2 para 1 mother by cesarean section at 36 weeks' gestation had loops of small intestine protruding from the abdominal cavity.

The infant had gastroschisis, a complete defect through all layers of the anterior abdominal wall. The pathogenesis is unclear. Possible causes include a defect in the differentiation of the mesenchyma of the lateral fold of the embryo, tearing of the umbilical cord from the right half of the abdominal wall, a vascular accident affecting the right umbilical vein, and early disruption of the omphalocele with resorption of its remains.

Most infants with gastroschisis are born prematurely. Clinically, the lesion presents as visceral exposure, almost always to the right side of the umbilical cord. There is no sac covering the viscera. The extra-abdominal intestine may look normal; more commonly, however, it appears to be thickened, foreshortened, edematous, and discolored. There may be a variably developed serosal peel on its surface, resulting from in utero exposure of the intestine to amniotic fluid. Malrotation, shortening, stenosis, or atresia of the intestine is common. Extra-abdominal abnormalities are rare.

Maintaining the infant's temperature is critical. Heat loss can be reduced by covering the exposed intestine with warm, moist saline gauze and placing the infant under a radiant warmer. Most infants with gastroschisis are dehydrated at birth and require intravenous hydration. A nasogastric tube is necessary for gastrointestinal decompression. Prophylactic parenteral broad-spectrum antibiotics may prevent sepsis, a frequent complication.

Gastroschisis requires prompt surgical intervention. In most cases, it can be treated with primary closure of the fascia after the abdominal wall is stretched and the viscera are reduced into the abdominal cavity. Occasionally, a staged repair may be necessary, involving application of a Silastic silo and gradual reduction of the protruding viscera, with delayed closure of the defect as the overlying abdominal wall expands.

Postoperative ventilatory support is often required for a few days. Most infants need parenteral nutrition for 2 to 3 weeks postoperatively, until the bowel begins to function normally.