Abdominal complications following cardiopulmonary bypass in open-heart surgery.

Open-heart surgery was performed on 1686 adult patients between 1980 and 1984, with a mortality rate due to abdominal complications of 0.6%. Every operation involved the use of cardiopulmonary bypass (CPB). Abdominal complications occurred in 1.6%, with an overall mortality rate of 36%. The most frequent complication was gastrointestinal (Gl) bleeding (61%). The mortality of the patients who bled from the Gl tract was 53%. Other complications encountered were gastroduodenal ulcer, colitis, ileus, subphrenic abscess and intraperitoneal bleeding. Prolonged CPB and low output syndrome preceded multiple organ failure, which occurred in 39% of those who had abdominal complications and in 59% of those who bled. Gl bleeding after CPB did not correlate with a previous history of gastric ulcer. Reoperation because of cardiac tamponade or excessive chest tube drainage was a factor predisposing to Gl bleeding. The mortality and abdominal complication rates were significantly higher in valve surgery than in coronary revascularization.