Perfusion of the abdomen is determined by cardiac function and circulation. Intestinal ischemia can be caused by Non occlusive bowel ischemia (NOD) that is important in internal as well as surgical intensive care medicine. Cardiac medication can influence perfusion of the bowel: 1) digitalis increases muscular tonus and decreases perfusion regulation b) diuretics lead to hypovolemia, hypotonia and malperfusion, c) antihypertensive medication can cause intraoperative hypotension that demands catecholamines, d) catecholamines can reduce perfusion by pathologic vasoconstriction in the splanchnicus area. Preoperative medication should respect 1) preoperatively taken ACE-inhibitors should be given postoperatively, as they have protective influence on the microcirculation of the bowel, 2) beta-blockers stabilize the myogenic tonus of the abdominal vessels, reduce an overshot of the parasympatheticus and diminish the risk of neurogenic abdominal shock, 3) catecholamines should be used with respect to ischemia of the bowel. Therapy of NOD should be focused on the primary vascular and hemodynamic causes and also take care for bacterial translocation and consecutive sepsis.