Intestinal ischemia

Definition

• Insufficiency of delivery of O2, nutrients and removal of waste toxins to small bowel tissue
• Resulting in cellular and tissue damage
• The extent of tissue damage will depend on
  • The number of vessels affected
  • The acuity of onset
  • The duration of insult
  • The degree of collateral circulation

Classification

• Acute or Chronic
• Arterial or Venous
• Embolic or Thrombotic
• Arterial (85-95%)
  • Acute arterial mesenteric ischaemia
    • Embolic > Thrombotic
  • Chronic mesenteric ischemia
    • Atherosclerosis in proximal SMA/Celiac
    • Median Arcuate Ligament Syndrome (extrinsic compression of Coeliac)
    • Aortic dissection, arteritis, Buerger’s disease
• Venous (1-15%): 
  • Mesenteric venous thrombosis or strangulated segment
• Colonic
  • Acute colonic ischemia
  • Chronic ischemic colitis
• Nonocclusive mesenteric ischemia