What is the typical color of bilious vomit?

The Color of Bilious Vomit

Bilious vomit is characteristically dark green in color, indicating the presence of bile in the vomitus, which is an ominous sign in neonates that suggests the possibility of bowel obstruction requiring urgent evaluation. 1

Characteristics of Bilious Vomit

• Bilious vomit has a distinctive dark green color due to the presence of bile pigments 2
• The green coloration comes from bile that has refluxed from the duodenum into the stomach and is subsequently vomited 3
• In contrast to the common yellow color often mistakenly identified as bile, true bilious vomit is dark green 2
• The presence of bile in vomitus indicates that the point of obstruction is distal to the ampulla of Vater 1

Clinical Significance

• Bilious vomiting, particularly in neonates, is synonymous with intestinal obstruction until proven otherwise 4, 5
• In neonates, bilious vomiting within the first 72 hours of life is especially concerning, with 20% of cases representing midgut volvulus 1
• Bilious vomiting combined with gastric distension strongly suggests proximal bowel obstruction 1
• This symptom requires immediate medical attention and is considered a surgical emergency until proven otherwise 5

Common Causes of Bilious Vomiting

• In neonates, common causes include:
  • Intestinal atresia (duodenal, jejunal, ileal) 1, 6
  • Malrotation with or without volvulus 6, 5
  • Meconium ileus 5
  • Hirschsprung disease 1
• In older infants and children:
  • Internal hernia (particularly after gastric bypass surgery) 1
  • Jejunal stricture 7
  • Intussusception 1

Diagnostic Considerations

• Bilious vomiting should be differentiated from non-bilious regurgitation or reflux 1
• Healthcare providers often misidentify bile color, with many incorrectly selecting yellow instead of dark green 2
• Educational interventions can significantly improve the recognition of true bilious vomit 2
• The presence of a "triple bubble" sign on radiographs may indicate jejunal atresia in cases of bilious vomiting 6

Management Approach

• Immediate placement of a nasogastric or orogastric tube for gastric decompression 5
• Abdominal radiographs should be obtained to look for dilated bowel loops and air-fluid levels 5
• Further imaging may include contrast studies to identify the specific cause of obstruction 1
• Early surgical consultation is essential as many causes require operative intervention 5