Review Question - QID 106416

A new born infant with bilious vomiting and the classic "double-bubble" sign on abdominal radiograph is suffering from duodenal obstruction and needs immediate surgical evaluation.

The classic "double-bubble" sign seen on radiographs of the newborn abdomen shows air in the stomach and duodenum. It can represent duodenal obstruction from one of several causes: duodenal atresia, duodenal web or stenosis, annular pancreas, malrotation of the bowel with a midgut volvulus, or Ladd's bands (obstruction of the duodenum by a fold of peritoneum). These neonates are often volume depleted with electrolyte abnormalities at the time of the condition's recognition and will commonly need IV resuscitation and electrolyte repletion.

Loening-Baucke and Kimura discuss the differential diagnosis for the neonatal intestinal obstruction. Plain radiographs of the abdomen do not allow for definitive differentiation of small bowel obstruction from large bowel obstruction and surgical evaluation is often necessary. Bilious vomiting, with or without abdominal distention, is usually the first sign of small bowel obstruction.

Kiely et al. discuss the surgical treatment of malrotation with volvulus. Typically, the treatment includes conterclockwise detorsion of the midgut vovulus and evaluation and removal of any necrotic bowel. These authors specifically describe the successful use of systemic infusion of tissue-type plasminogen activator (in addition to standard surgical procedure) in 2 case reports of neonates with severe intestinal ischemia due to volvulus.

Figure A is an abdominal radiograph (erect posture) showing the double bubble sign, indicative of duodenal obstruction. Illustration A shows a schematic of intestinal malrotation with midgut volvulus.

Incorrect Answers:
Answer 1: While gastric decompression will help the infant initially, following with making her NPO and observation alone would not be appropriate.
Answer 2: The obstruction is at the level of the duodenum. Rectal decompression is not appropriate.
Answer 3: While this child may need prophylactic preoperative antibiotics, the cause of the infant's symptoms are not infections and antibiotics alone are not appropriate.
Answer 5: There are very few indications for giving an infant a CT scan. If necessary, duodenal obstruction can be confirmed with a barium enema or oral contrast study.