title: Difficulties in predicting outcome in cardiac surgery patients.
abstract: OBJECTIVE
  To evaluate a novel combination of preoperative, intraoperative, and postoperative variables (including the Parsonnet, and the Acute Physiology and Chronic Health Evaluation II and III [APACHE II and III] scores) in cardiac surgery patients in order to predict hospital outcome, complications, and length of stay.
  
  
  METHODS
  Prospective survey.
  
  
  METHODS
  Adult intensive care unit (ICU) at a tertiary care cardiothoracic surgery center.
  
  
  METHODS
  All cardiac surgery patients admitted to the ICU over a 1-yr period.
  
  
  METHODS
  Medical history, Parsonnet score, intraoperative data (including bypass and ischemic times), APACHE II and III scores, complications, and outcome were collected for each patient.
  
  
  RESULTS
  One thousand eight patients were entered into the study. The mean Parsonnet score was 7.8 (range 0 to 33), mean APACHE II score 11.8 (range 2 to 33), and mean APACHE III score 42.5 (range 9 to 132). ICU mortality rate was 2.7% and hospital mortality rate was 3.8%. The mean APACHE II predicted risk of dying was 5.31%, which gave a standardized mortality ratio of 0.71. The above scores were all statistically well correlated with hospital mortality. Further, a logistic regression model was developed for the probability of hospital death. This model (which included bypass time, need for inotropes, mean arterial pressure, urea, and Glasgow Coma Scale) had an area under the receiver operating characteristic curve of 0.87, while the Parsonnet score had an area of 0.82 and the APACHE II risk of dying had an area of 0.84.
  
  
  CONCLUSIONS
  Cardiac surgery remains a difficult area for outcome prediction. A combination of intraoperative and postoperative variables can improve predictive ability.
authors.affiliation: Adult Intensive Care Unit, Royal Brompton National Heart and Lung Hospital, London, UK.
authors.forename: J S
authors.initials: JS
authors.lastname: Turner
authors.forename: C J
authors.initials: CJ
authors.lastname: Morgan
authors.forename: B
authors.initials: B
authors.lastname: Thakrar
authors.forename: J R
authors.initials: JR
authors.lastname: Pepper
mesh_terms: D018806:APACHE; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000401:mortality; D003422:Critical Care; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors