What are the common symptoms of occlusive mesenteric ischemia?
The common presenting symptoms of occlusive mesenteric ischemia vary by the cause of ischemia.
- • Patients with mesenteric ischemia caused by an acute embolus or thrombotic occlusion of the SMA usually present with the abrupt onset of severe, colicky, midabdominal pain. These patients may also become incontinent of bowel function because of tonic contractions of smooth muscle provoked by ischemia. These contractions cause severe pain but produce few abdominal physical examination findings. It is important to note that late findings of abdominal distension and guaiac-positive stool may be the only presenting signs in patients who are unable to communicate (e.g., those who are sedated, demented, or with altered mental status).
- • Patients with mesenteric ischemia caused by a thrombotic occlusion tend to present with a history consistent with mesenteric angina—recurrent postprandial mid or diffuse abdominal pain with or without radiation to the back. Associated weight loss is often present as a result of sitophobia. Additionally, patients may have diarrhea, steatorrhea, or protein-losing enteropathy, which can further complicate the chronically ischemic-induced atrophy of the small intestine.
- • Patients with venous occlusive disease generally describe a more nonspecific, insidious onset of abdominal pain, diarrhea, and emesis. This occurs when massive influx of fluid into the bowel wall and lumen causes systemic hypotension and an eventual decrease in arterial flow. It should be suspected in the appropriate clinical settings such as abdominal sepsis, hypercoagulability, and the use of oral contraceptive pills.