Organ failures due to low cardiac output syndrome following open heart surgery.

During the period from August, 1977 to December, 1984, a total of 3003 patients who received open heart surgery were treated postoperatively at the ICU of National Cardiovascular Center. Low cardiac output syndrome (LOS) developed in 669 (22.3%) patients. Organ failures due to LOS were studied in these patients. Although the overall mortality of postoperative patients was 5.6% and improved to around 4% in the later years, death rate of patients with LOS was persistently high (22.8%) and showed no tendency to improve even in the latest years. Moreover, the clinical results of those LOS patients who developed organ failure were extremely poor; the mortality of patients with respiratory failure (RF) accounted for 36.8% and that of patients with other organ failure exceeded 50%. The incidence of impaired organs in LOS patients was 49.9% in RF, 29.9% in acute renal failure (ARF), 18.4% in hepatic failure (HF), 16.4% in disseminated intravascular coagulation (DIC), 15.5% in central nervous system failure (CNSF), and 11.1% in gastrointestinal bleeding (GIB). Pathophysiological mechanisms as well as the management of these major complications caused by LOS are also discussed. Some patients developed multiple organ failure (MOF). Plasma exchange (PE) was performed on 16 patients who developed MOF. Improvement of various organ functions was obtained and consequently three patients were successfully treated by means of PE. Removal of various substances toxic to organs, supplement of deficient substances and cessation of the vicious cycle produced by the interaction of impaired organs in patients with MOF are major roles of PE in the treatment of MOF.