Most congenital gastrointestinal (GI) anomalies result in some type of intestinal obstruction, frequently manifesting with feeding difficulties, distention, and emesis at birth or within 1 or 2 days. Some congenital GI malformations, such as malrotation Malrotation of the Bowel Malrotation of the bowel is failure of the bowel to assume its normal place in the abdomen during intrauterine development. Diagnosis is by abdominal x-ray. Treatment is surgical repair. (See... read more 
, have a very good outcome, whereas others, such as congenital diaphragmatic hernia Diaphragmatic Hernia Diaphragmatic hernia is protrusion of abdominal contents into the thorax through a defect in the diaphragm. Lung compression may cause persistent pulmonary hypertension. Diagnosis is by chest... read more 
, have a poor outcome (mortality rate of 10 to 30%).
A common type of anomaly is atresia, in which a segment of the GI tract fails to form or develop normally, or it forms and then is destroyed by an intrauterine event (vascular disruption). The most common type is esophageal atresia Esophageal Atresia Esophageal atresia is incomplete formation of the esophagus, frequently associated with tracheoesophageal fistula. Diagnosis is suspected by failure to pass a nasogastric or orogastric tube... read more 
, followed by atresia in the jejunoileal region Jejunoileal Atresia Jejunoileal atresia is incomplete formation of part of the small intestine. Diagnosis is by abdominal x-ray. Treatment is surgical repair. (Also see Overview of Congenital Gastrointestinal Anomalies... read more 
and in the duodenum.
Immediate management includes bowel decompression (by continuous nasogastric suction to prevent emesis, which can lead to aspiration pneumonia or further abdominal distention with respiratory compromise) and referral to a center for neonatal surgery. Also vital are maintenance of body temperature, prevention of hypoglycemia with IV 10% dextrose and electrolytes, and prevention or treatment of acidosis and infections so that the infant is in optimal condition for surgery.
Because about one third of infants with a GI malformation have another congenital anomaly (up to 50% in those with congenital diaphragmatic hernia and up to 70% in those with omphalocele Omphalocele An omphalocele is a protrusion of abdominal viscera from a midline defect at the base of the umbilicus. (See also Overview of Congenital Gastrointestinal Anomalies.) In omphalocele, the herniated... read more 
), they should be evaluated for malformations of other organ systems, especially of the central nervous system, heart, and kidneys.
High Alimentary Tract Obstruction
Esophageal, gastric, duodenal Duodenal Obstruction The duodenum can be obstructed by atresia, stenosis, and pressure due to an extrinsic mass. (See also Overview of Congenital Gastrointestinal Anomalies.) This anomaly is the 2nd most common... read more 
, and sometimes jejunal obstruction should be considered when excess amniotic fluid ( polyhydramnios Polyhydramnios Polyhydramnios is excessive amniotic fluid; it is associated with maternal and fetal complications. Diagnosis is by ultrasonographic measurement of amniotic fluid. Maternal disorders contributing... read more ) is diagnosed, because such obstructions prevent the fetus from swallowing and absorbing amniotic fluid.
A nasogastric tube should be passed into the neonate’s stomach immediately after cardiovascular stability has been attained after delivery. Finding large amounts of fluid in the stomach, especially if bile-stained, supports the diagnosis of upper GI obstruction, whereas inability to pass the tube into the stomach suggests esophageal atresia (or nasal obstruction [eg, choanal atresia]).
Jejunoileal and Large-Bowel Obstruction
( See also Meconium Ileus Meconium Ileus Meconium ileus is obstruction of the terminal ileum by abnormally tenacious meconium; it most often occurs in neonates with cystic fibrosis. Meconium ileus accounts for up to 33% of neonatal... read more and Professional.see also Heading on Page Meconium Plug Syndrome Meconium Plug Syndrome Meconium plug syndrome is colonic obstruction caused by thick meconium. Diagnosis is based on radiographic contrast enema and sometimes testing for Hirschsprung disease. Treatment is radiographic... read more .)
Obstruction of the jejunum and ileum can occur as the result of jejunoileal atresia Jejunoileal Atresia Jejunoileal atresia is incomplete formation of part of the small intestine. Diagnosis is by abdominal x-ray. Treatment is surgical repair. (Also see Overview of Congenital Gastrointestinal Anomalies... read more , malrotation Malrotation of the Bowel Malrotation of the bowel is failure of the bowel to assume its normal place in the abdomen during intrauterine development. Diagnosis is by abdominal x-ray. Treatment is surgical repair. (See... read more , or meconium ileus. Large-bowel obstruction is typically caused by meconium plug syndrome, or colonic or anal atresia Anal Atresia Anal atresia is an imperforate anus. (Also see Overview of Congenital Gastrointestinal Anomalies.) In anal atresia, the tissue closing the anus may be several centimeters thick or just a thin... read more .
In 75% of cases, no history of maternal polyhydramnios exists because much of the swallowed amniotic fluid can be absorbed from the intestine proximal to the obstruction. These disorders, other than malrotation, intestinal duplication, and Hirschsprung disease Hirschsprung Disease Hirschsprung disease is a congenital anomaly of innervation of the lower intestine, usually limited to the colon, resulting in partial or total functional obstruction. Symptoms are obstipation... read more 
, typically manifest in the first few days of life with feeding problems, abdominal distention, and emesis that may be bilious or fecal. The neonate may pass a small amount of meconium initially but thereafter does not pass stools. Malrotation, intestinal duplication, and Hirschsprung disease can manifest in the first several days of life or years later.
General diagnostic approach and preoperative management include the following:
Giving nothing by mouth
Placing a nasogastric tube to prevent further bowel distention or possible aspiration of vomitus
Correcting fluid and electrolyte disturbances
Taking a plain abdominal x-ray
Doing a contrast enema to delineate the anatomy (the enema may also relieve obstruction in meconium plug syndrome or meconium ileus)
For Hirschsprung disease, a rectal biopsy is needed.
Defects in Abdominal Wall Closure
Several congenital defects involve the abdominal wall (eg, omphalocele Omphalocele An omphalocele is a protrusion of abdominal viscera from a midline defect at the base of the umbilicus. (See also Overview of Congenital Gastrointestinal Anomalies.) In omphalocele, the herniated... read more , gastroschisis Gastroschisis Gastroschisis is protrusion of the abdominal viscera through a full-thickness abdominal wall defect, usually to the right of the umbilical cord insertion. (See also Overview of Congenital Gastrointestinal... read more 
), allowing protrusion of the viscera through the defect.
