THE APACHE-III PROGNOSTIC SYSTEM - CUSTOMIZED MORTALITY PREDICTIONS FOR SPANISH ICU PATIENTS

Objective: To customize the Acute Physiology and Chronic Health Evalua tion (APACHE) III mortality equation for Spanish admissions to the int ensive care unit (ICU) and evaluate its discrimination and calibration . Design: Prospective multicenter inception cohort study. Setting: SG ICUs located in all regions of Spain. Patients: 10929 adult patients s elected by a systematic sampling method. All types of critical care pa tients were included, including coronary bypass patients. but excludin g those with burn injury, those admitted for pacemaker implants, patie nts under 16 pears of age, and patients with length of ICU stay < 6 h. Measurements and results: Data collection in the first 24 h after pat ient admission included: APACHE III score, treatment location prior to ICU admission. and main ICU admission diagnosis. Using these variable s, a model for predicting hospital mortality was constructed, adapted to Spain, and its discriminating ability was assessed by the area belo w the ROC curve. which was 0.83. The model was validated using the jac knife method and the area below the receiver operating characterisitic (ROC) curve for the cross-validated predictions was 0.82. The percent age of patients correctly classified at 0.50 risk of death was 82.3 %. Model calibration was evaluated by analysis of the agreement between the observed and cross-validated predicted mortality using the Hosmer- Lemesho is test, which gave a value of (H) 12.27. with no statistical significance, i.e., good calibration. Conclusions: We have customized the APACHE III mortality prediction system for the Spanish population. This adapted model has demonstrated the requisite validation, calibra tion, and discrimination for its use among Spanish critical care patie nts.