In order to identify peroperative risk factors and to evaluate different etiological factors in developing postoperative gastrointestinal complications, clinical variables were studied in 3493 patients undergoing adult cardiac surgery. There were 86 gastrointestinal complications, 2.9 %, with an overall mortality among these of 22.1 %: the mortality rate was 3.9 % for all patients undergoing cardiac surgery at our institution (p < 0.001). Paralytic ileus, intestinal ischemia, and acute cholecystitis were the most frequently seen complications. Arterial hypertension, smoking and poor preoperative cardiac function, clinical instability, and the need for an emergency operation were distinct clinical risk factors. Cardiopulmonary bypass time was, by itself, not an important factor. Embolic etiology was also ruled out. The incidence of peroperative myocardial infarction, low postoperative cardiac output necessitating massive use of vasopressor substances and/or intraaortic balloon pumping were significantly more often observed in patients who subsequently developed gastrointestinal complications. The common etiological factor in developing gastrointestinal complications of any kind, after cardiac surgery, seems to be postoperative splanchnic hypoperfusion with visceral ischemia. In order to reduce postoperative morbidity and mortality it is essential to identify patients at risk, support preoperative poor cardiac function, and to carefully monitor these patients postoperatively for abdominal complications to reach an early diagnosis.
