Obstruction of small intestine

Etiology

• Mechanical obstruction of small intestine or proximal colon, eg, adhesions, volvulus, Crohn’s disease
• Acute paralytic ileus due to:
  • Gastrointestinal (GI) or abdominal surgery
  • Peritoneal irritation, eg, peritonitis, pancreatitis, ruptured viscus
  • Severe medical illness, eg, sepsis, electrolyte abnormality
  • Drugs, eg, opioids, anticholinergics
  • Myxedema (hypothyroidism)
• Chronic intestinal pseudo-obstruction