Gastroschisis is an opening in the abdominal wall that allows the stomach and small and large intestines to extend outside the body. This occurs during fetal development. The opening almost always occurs to the right of the navel (umbilicus) and is usually less than two inches in size.
Gastroschisis is an uncommon birth defect, seen in about 1 of 5,000 births. Although about 10% of infants with gastroschisis have an intestinal atresia in which a portion of the intestine does not develop, the defect is rarely associated with other genetic abnormalities.
The cause of gastroschisis is unknown.
With the abdominal contents outside of the body and no protective sac covering these contents, the intestine is exposed to amniotic fluid, which may irritate the bowel, causing it to swell and shorten. The damage becomes more severe with prolonged exposure to amniotic fluid.
As the fetus grows, the small tight opening may decrease the blood supply to the intestine and/or the bowel may twist around itself. Both of these problems can result in poor bowel function after the baby is born. This can lead to long-term feeding problems.
Gastroschisis is often diagnosed prenatally and can be seen on ultrasound as early as the 14th week of pregnancy. When maternal alpha-fetoprotein (AFP) levels are elevated, obstetricians look for defects by having the expectant mother undergo a detailed prenatal ultrasound. With gastroschisis, this test will show loops of intestines floating freely in amniotic fluid. More frequent ultrasounds are generally recommended to continue monitoring the fetus. The mother is usually referred to a pediatric surgeon for consultation and counseling.
Once the diagnosis is made, you might want to plan for your baby to be delivered in a hospital with a neonatal intensive care unit, where he/she can receive the special care that will be required.
If ultrasound tests indicate that the baby's lungs are mature, you may be advised to have a cesarean section at about 36 weeks of pregnancy. Surgery for the gastroschisis will be done as soon as the infant's condition is stabilized, usually within 12 to 24 hours after delivery.
When the amount of bowel outside the abdomen is small, complete repair can be done with one operation; this is possible in approximately two-thirds of cases. This procedure returns the bowel to the abdominal cavity and closes the opening.
If the amount of bowel outside the abdomen is large, or if the baby's condition is unstable, the repair may need to be done in several steps (staged). This staged procedure usually occurs over three to 10 days but can take longer in some cases. A silastic (silicone plastic) pouch is first placed over the baby's exposed bowel and anchored to the surrounding muscle. Each day, the pouch is tightened to push the intestine back into the abdominal cavity. When the intestine is back in its proper place within the abdomen, the pouch is removed and the opening is surgically closed. Some babies may need the help of a breathing machine during this time.
In most babies, the long-term prognosis is good. Nevertheless, some babies who have sustained injuries to the bowel due to direct contact between the intestines and amniotic fluid, or due to the intestine being twisted or damaged during fetal development or delivery, may develop short gut syndrome. Symptoms of short gut syndrome include diarrhea, slow weight gain and deficiencies of essential vitamins and minerals. Babies with short gut syndrome may require a prolonged course of intravenous nutrition (TPN) delivered at the hospital or at home, and will need to be closely monitored.