Bilious vomiting in the newborn: How often is it pathologic?

Background/Purpose: Intestinal obstruction is one of the most common reasons for admission to a neonatal surgical unit and frequently is manifest by bilious vomiting. Not all cases of neonatal bilious vomiting are caused by intestinal obstruction. This study aimed to investigate the outcome of neonates with bilious vomiting. Methods:A prospective audit was undertaken of all neonates with a history of bilious vomiting referred to a regional pediatric surgical unit during a 2-year period (1998 to 2000). Infants with bilious nasogastric aspirates but no vomiting were not included. Demographic details, symptomatology, investigations, and final diagnoses were recorded. Subsequent clinical progress was ascertained by out-patient review or telephone interview. Results: Sixty-three consecutive neonates (35 boys, 28 girls) were identified with a median gestational age of 40 (range 31 to 42) weeks and median birth weight of 3.5 kg (range 1.67 to 4.64). Median age at presentation was 26 hours (range, 9 hr to 28 days). A surgical cause of bilious vomiting was identified in 24 (38%): Hirschsprung's disease (n = 9), small bowel atresia (n = 5), intestinal malrotation (n = 4), meconium ileus (n = 3), meconium plug (n = 1), colonic atresia (n = 1), and milk inspissation (n = 1). Nineteen of these had both abdominal signs and an abnormal plain abdominal radiograph, and 4 had an abnormal abdominal radiograph only. In one infant with intestinal malrotation, clinical examination and plain radiography were unremarkable. After definitive surgery, all 24 infants were well at a median age of 14 (7 to 28) months. No surgical cause for bilious vomiting was found in 39 (62%) neonates whose symptoms resolved with conservative management. Conclusions: These data emphasize the maxim that bilious vomiting in the newborn should be attributed to intestinal obstruction until proved otherwise. However, in this prospective audit, bilious vomiting was not caused by intestinal obstruction in 62% of cases, and most of these infants suffered no further sequelae.