Objectiveor=to75 yrs of age after cardiac surgery.DesignInception cohort study.SettingA tertiary care, 54-bed cardiothoracic intensive care unit (ICU).Patientsor=to75 yrs admitted over a 30-month period for cardiac surgery.InterventionCollection of data on preoperative factors, operative factors, postoperative hemodynamics, and laboratory data obtained on admission and during the ICU stay.Measurements and Main ResultsPostoperative death, frequency rate of organ dysfunction, nosocomial infections, length of mechanical ventilation, and ICU stay were recorded.15 mm Hg, stroke volume index of <30 mL/min/m2300 mg/dL after surgery, and anemia beyond the second postoperative day. During the study period, the study cohort used 6,859 (21.5%) ICU patient-days out of a total 31,867 ICU patient-days. Nonsurvivors used 2,023 (30%) ICU patient-days and patients with morbidity used 5,903 (86%) ICU patient-days.ConclusionsSevere underlying cardiac disease (including shock, requirement for mechanical circulatory support, hypoalbuminemia, and hepatic dysfunction), intraoperative blood loss, surgical reexploration, long ischemic times, immediate postoperative cardiovascular dysfunction, global ischemia and metabolic dysfunction, and anemia beyond the second postoperative day predicted poor outcome in the elderly after cardiac surgery. Postoperative morbidity and mortality disproportionately increased the utilization of intensive care resources in elderly patients. Future efforts should focus on preoperative selection criteria, improvement in surgical techniques, perioperative therapy to ameliorate splanchnic and global ischemia, and avoidance of anemia to improve the outcome in the elderly after cardiac surgery. (Crit Care Med 1998; 26:225-235)