Acute mesenteric ischemia

Acute vascular occlusion within the mesenteric circulation leads to ischemic damage of the corresponding bowel segment, which starts on the mucosal level and progresses transmurally. Report on pathogenesis, clinical picture and treatment of various forms of intestinal ischemia. Analysis of the available literature taking into consideration our own experience. Frequently, predisposing diseases and risk factors are present (e.g., cardiac diseases, hypercoagulability, status post cardiac surgery, circulatory failure, or administration of vasoconstrictive drugs). Acute small bowel ischemia-caused by either mesenteric embolism, mesenteric artery thrombosis, nonocclusive mesenteric ischemia (NOMI) or mesenteric venous thrombosis-represents an acute emergency. If this condition is suspected clinically, the diagnosis must be established immediately by computed tomography of the abdomen with intravenous administration of contrast medium in order to prevent irreversible damage to the small bowel. Medical treatment is supportive. If possible, occluded vessels may be re-opened either by radiologic intervention or surgically. Irreversibly damaged bowel segments must be surgically removed. Ischemic colitis has a benign course in most cases if limited to reversible mucosal damage. The diagnosis is based mainly on colonoscopy and computed tomography findings, and treatment is symptom oriented. Rarely, severe manifestations with a worse prognosis due to considerable comorbidities occur. In such cases, surgical removal of the ischemic bowel is frequently required. Even today, acute mesenteric ischemia is associated with a poor prognosis. To improve survival and to reduce long-term morbidity, a rapid and systematic diagnostic workup is mandatory.