Clinical manifestations-acute mesenteric ischemia

• Arterial occlusion: sudden intense abd pain out of proportion to tenderness on exam

• Venous occlusion: often more insidious in onset, intermittent pain with peaks and valleys

• Nonocclusive: abd distention & pain, n/v, lower GI bleeding due to mucosal sloughing; often occurring after episode of hypoperfusion (eg, cardiac event or shock)

• Exam ranges: unremarkable ± abd distention to peritoneal (infarction); ⊕ FOBT ~75%