APACHE II Score to Predict the Outcome of ventilated patient in Intensive Care Unit of Tertiary Level Hospital

Abstract

Background

Predicting outcomes in critically ill mechanically ventilated patients in the intensive care unit (ICU)s remains challenging due to disease complexity and resource constraints, particularly in low- and middle-income countries. The Acute Physiology and Chronic Health Evaluation II (APACHE II) score is one of the many prediction scores widely used for severity assessment, with variable predictive performance across different settings. The study aimed to evaluate the effectiveness of the APACHE II scoring system in predicting mortality among mechanically ventilated patients admitted to a medical ICU in central Nepal.

Methods

 This hospital-based cross-sectional study was conducted over a period of one year in a 17-bed medical ICU of a university teaching hospital. A total of 216 mechanically ventilated adult patients were enrolled. APACHE II scores were calculated using the worst physiological values recorded within the first 24 hours of mechanical ventilation. Patient outcomes were categorized as survival or death at ICU discharge. Predictive performance was assessed using receiver operating characteristic (ROC) curve analysis.

Results

 Of the 216 patients, 129 (59.7%) were male, with a mean age of 55.04 ± 18.89 years. Overall ICU mortality was 64.35%. The mean APACHE II score was significantly higher among non-survivors compared to survivors (31.99 ± 8.92 vs. 17.66 ± 5.73; p < 0.001). Mortality increased progressively with higher APACHE II scores, and no patient with a score greater than 30 survived. The area under the ROC curve for APACHE II in predicting mortality was 0.913 (95% CI: 0.877–0.949; p < 0.001), indicating excellent discriminatory ability.

Conclusion

 APACHE II is a reliable and highly accurate predictor of mortality among mechanically ventilated ICU patients in this setting. A score above 30 was uniformly associated with death, underscoring its value in prognostication, clinical decision-making, and family counseling in resource-limited ICUs.