Intestinal Ischemia, Nonocclusive

• • No embolic or thrombotic cause of vascular obstruction

  • Associated low flow state (sepsis, cardiac dysrhythmia)

  • Severe, diffuse abdominal pain

  • Gross or occult intestinal bleeding

  • Minimal physical findings

Epidemiology

• • In about 25% of patients with intestinal ischemia, vascular occlusion does not involve a major artery or vein (although arterial stenosis is usually present)

  • In the presence of some other acute disease such as a cardiac dysrhythmia or sepsis, splanchnic vasoconstriction occurs, and the intestine becomes ischemic because of low perfusion pressure and flow

  • -Arterial blood is shunted away from the villi in these circumstances, and the ischemic villi are destroyed if the condition persists

Symptoms and Signs

• • Severe, poorly localized abdominal pain that is often out of proportion to physical findings

  • Nausea and vomiting

  • Diarrhea

  • Shock

  • GI bleeding

  • Abdominal distention

  • Abdominal tenderness

  • Peritonitis

Laboratory Findings

• • Leukocytosis

  • Serum amylase is elevated

  • Significant base deficits

  • Increased serum phosphate

  • Anemia

  • Increased serum lactate

Imaging Findings

• • Abdominal x-ray

  • -Nonspecific

    -Absence of intestinal gas

    -Diffuse distention with air-fluid levels

  • Specific findings occur late: Intramural gas and gas in the portal venous system

  • GI contrast radiography: May reveal "thumbprinting" and disordered motility

  • CT scan

  • -Diffuse distention with air-fluid levels

    -Intestinal wall thickening

    -Intramural gas and gas in the portal venous system

  • Arteriography: Documents the absence of major vascular occlusion but is not otherwise diagnostic in most cases

• • The diagnosis is suspected when acute abdominal pain develops in a potentially susceptible patient

  • -Clinical picture is similar to that of arterial thrombosis, but the onset is less often sudden

  • Ischemia is most pronounced on the antimesenteric border, and the mucosa may be extensively involved before abnormalities are visible on the serosal surface

  • -There are often ischemic areas in other organs such as liver and spleen

Rule Out

• • Intestinal ischemia due to embolic or thrombotic processes

  • Acute pancreatitis

  • Intestinal obstruction

• • CBC

  • Serum electrolytes

  • Serum amylase

  • Serum lactate

  • ABG measurements

  • Abdominal x-ray

  • CT scan

  • Arteriography

When to Admit

• • All cases

• • Resection of all involved gut

  • -A second-look operation is performed 12-24 hours later if marginally viable bowel was left

  • Vascular reconstruction is ineffective

Surgery

Indications

• • Suspected mesenteric ischemia

Contraindications

• • Necrotic bowel should be resected unless the extent of damage is so great that satisfactory life could not be expected

Medications

• • Massive volume support and antibiotics

  • Intra-arterial infusion of papaverine

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