A comparison of Simplified Acute Physiology Score II, Acute Physiology and Chronic Health Evaluation II and Acute Physiology and Chronic Health Evaluation III scoring system in predicting mortality and length of stay at surgical intensive care unit

Background: In critically ill patients, several scoring systems have been developed over the last three decades. The Acute Physiology and Chronic Health Evaluation (APACHE) and the Simplified Acute Physiology Score (SAPS) are the most widely used scoring systems in the intensive care unit (ICU). The aim of this study was to assess the prognostic accuracy of SAPS II and APACHE II and APACHE III scoring systems in predicting short-term hospital mortality of surgical ICU patients. Materials and Methods: Prospectively collected data from 202 patients admitted to Mashhad University Hospital postoperative ICU were analyzed. Calibration was estimated using the Hosmer-Lemeshow goodness-of-fit test. Discrimination was evaluated by using the receiver operating characteristic (ROC) curves and area under a ROC curve (AUC). Result: Two hundred and two patients admitted on post-surgical ICU were evaluated. The mean SAPS II, APACHE II, and APACHE III scores for survivors were found to be significantly lower than of non-survivors. The calibration was best for APACHE II score. Discrimination was excellent for APACHE II (AUC: 0.828) score and acceptable for APACHE III (AUC: 0.782) and SAPS II (AUC: 0.778) scores. Conclusion: APACHE II provided better discrimination than APACHE III and SAPS II calibration was good at APACHE II and poor at APACHE III and SAPS II. Use of APACHE II was excellent in this post-surgical ICU.Keywords: APACHE II, APACHE III, ICU mortality, SAP