Intestinal obstruction

Intestinal obstruction may be described variously as:

• simple - lumen obstructed, blood supply intact
• strangulated - blood supply occluded
• closed loop - both limbs of loop are obstructed
• partial or complete

It may be further classified according to the

• rate of onset:
  • acute e.g. strangulated hernia
  • acute-on-chronic e.g. adhesional obstruction
  • chronic e.g. Crohn's disease
• site along the bowel:
  • very high e.g. pyloric stenosis
  • high small bowel e.g. jejunal tumour
  • distal small bowel e.g. gallstone ileus
  • low colon e.g. rectal carcinoma
• site of pathology in relation to the bowel wall:
  • in lumen
  • in wall
  • outside wall

Large bowel obstruction is principally due to:

• carcinoma } 90% of
• diverticulitis } cases
• volvulus

Small bowel obstruction is mainly due to:

• incarcerated hernia
• adhesions