Omphalocele and Gastroschisis With Dr. Foong-Yen Lim

Gastroschisis is a full thickness abdominal wall defect just to the right of the umbilicus, in which peritoneal contents, most often intestines, protrude through the abdomen without any membranous cover.

Omphalocele is right through the middle of the umbilicus and has a membranous cover.

Omphalocele is a congenital disorder and can have associated anomalies, but gastroschisis occurs in otherwise normal babies that have an intrauterine event during development.

Very high level of alpha fetal protein is associated with gastroschisis or omphalocele.

Alpha fetal protein (AFP) is a screening test, but ultrasound imaging is needed to definitively diagnose abdominal wall defects.

For gastroschisis, only ultrasound confirmed diagnosis is obtained without additional imaging.

For omphalocele, besides ultrasound, MRI and echocardiogram are routinely obtained because these patients may have other associated anomalies.

Fetal growth is tracked monthly in gastroschisis and omphalocele cases because there is concern for significant growth restriction.

Biophysical profile and non-stress testing are needed because intrauterine growth restriction and intrauterine fetal demise (IUFD) can occur in these patients.

If surveillance imaging becomes worrisome enough regarding intrauterine fetal demise, the mother and fetus need to be admitted for continuous monitoring or emergent delivery.

Gastroschisis is most common among babies born to young mothers of low gravidity, usually first pregnancy, with 75% being first born and 25% in second or subsequent pregnancies.

Nearly 60% of gastroschisis cases are premature.

More than 90% of gastroschisis infants are born less than 2,500 grams in weight due to intrauterine growth restriction.

Pseudoephedrine has an odds ratio of 4.2 times for gastroschisis compared to aspirin alone at 2.7.

Other risk factors for gastroschisis include acetaminophen, vitamin B deficiencies, drug use, and some genetic predispositions.

Mothers with omphalocele are usually advanced in age compared to the gastroschisis group, with advanced maternal age having an odds ratio of 3.3.

Major risk factors for omphalocele are trisomy 13, 18, and 21, which occur in anywhere between 35 and 90% of patients with omphalocele.

Crucial immediate postnatal procedures include minimizing heat loss and fluid loss, otherwise babies can show up extremely dehydrated and cold.

These babies can have significant acidosis and pulmonary hypertension.

Primary closure is considered if the bowel looks pristine, non-thickened, non-inflammatory, with only small amount outside and enough abdominal domain to push them all back very quickly.

Staged closure is favored if the defect is large or there are issues with the bowel, including atresia, compromised bowel, or perforation.

Some patients develop intestinal perforation after only two to four days of enteral feeding.

In sutureless closure, after pushing the bowel back in, babies are not taken to the operating room for suture closure; instead, the umbilical cord is placed over with dressing, and skin will grow over, although a small umbilical defect may remain that can close spontaneously over time.

For small bowel atresia encountered during closure, management options include tapering the dilated portion of bowel or resecting the bowel before tapering.

For omphalocele with no significant respiratory issues, sequential reduction using meshes is the best option, sewing meshes to the edges of the fascia without interrupting the membrane.

After sequential reduction with plastic clips, the patient is taken to the operating room for delayed primary closure of the fascia and skin.