Duodenal Atresia

Incidence 1:5000–10,000 live births

Male to female incidence is equal

Trisomy 21 in 20–30%

45% are premature infants of pregnancy complicated by polyhydramnios

Incidence of polyhydramnios 32–81%

Mortality 3–5%; due not to duodenal atresia but to associated CHD or prematurity

Hypoxemia associated with immature lungs

Hypoxemia due to CHD, persistent fetal circulation (pulm Htn)

Ventilation problems associated with prematurity.

Other associated anomalies in 50% of cases: esophageal atresia (7%), other intestinal atresias, renal anomalies (5%), malrotation of the gut (30%), volvulus, imperforate anus (3%), annular pancreas (25%).

CHD associated with trisomy 21 (ASD, VSD, AV canal).

Aspiration on induction of anesthesia secondary to bowel obstruction.

May be associated with cystic fibrosis.

Late presentation can be associated with dehydration, hypovolemia, and hypochloremic alkalosis.

Frequently premature infant of pregnancy complicated by polyhydramnios.

Polyhydramnios may occur in the absence of premature birth.

Diagnosis frequently made by prenatal ultrasound, allowing for parental counseling and planning for early repair; may not be detected until 28–32 wk gestation because of delay in development of proximal duodenal dilation.

Vomiting after birth: May be copious and bile stained. If obstruction is proximal to ampulla of Vater, emesis is nonbilious.

Flat abdomen.

Dx is made by “double bubble” on abdominal x-ray (dilated stomach and proximal duodenum).

Obstruction may be caused by partial obstruction: stenosis with perforated web or diaphragm rather than atresia; Dx may be delayed.

Coexisting distal intestinal atresia is rare (<1%).

Unknown in sporadic cases

More common in trisomy 21