Comparative performance of mSOFA, APACHE II, APPS, and MPM II scores in predicting mortality among mechanically ventilated surgical ICU patients: a prospective cohort study

Background Accurate mortality prediction in surgical intensive care units (ICUs) is fundamental for risk stratification, clinical decision making and resource allocation. Although several prognostic scoring systems are widely employed including APACHE II, mSOFA, MPM II, and APPS, their comparative performance in mechanically ventilated surgical ICU patients within resource limited settings remains inadequately characterized. Objectives To identify independent clinical predictors of in-ICU mortality and to compare the discriminatory accuracy of APACHE II, mSOFA, MPM II and APPS scoring systems in mechanically ventilated surgical ICU patients. Methods This prospective cohort study included 106 postoperative mechanically ventilated patients admitted to the Surgical Intensive Care Unit at Zagazig University Hospitals between July 2023 & June 2025, following approval by the institutional review board (IRB No. ZU-IRB #10620/22-03-2023). All prognostic scoring systems were calculated on the first day of invasive mechanical ventilation (IMV). Independent predictors of outcome were identified using binary logistic regression analysis, while discriminatory performance was evaluated through receiver operating characteristic (ROC) curve analysis with estimation of the area under the ROC curve (AUROC). A two-tailed p-value < 0.05 was considered statistically significant. Results Overall in-ICU mortality was 60.4% (64/106 patients). Mortality was significantly associated with lower Glasgow coma scale (GCS) scores, lower blood pressures, lower temperature, reduced urine output, lower serum albumin, and higher serum creatinine (all had p-value < 0.05). mSOFA had the highest AUROC (0.763; 95% CI: 0.673–0.853), followed by APACHE II (0.742; 95% CI: 0.648–0.836) and MPM II (0.656; 95% CI: 0.554–0.759). APPS showed poor discrimination (AUROC 0.535; p = 0.539). On multivariate logistic regression, mSOFA was the only independent predictor of mortality (OR 1.342; 95% CI: 1.091–1.651; p = 0.005). Conclusion The mSOFA score showed the numerically highest AUROC (0.763) in this single-center cohort and was accordingly independent predictor of mortality. These findings support that it may be useful, simple adjunct for risk stratification in resource limited surgical ICU settings. Multicenter validation studies are required before definitive recommendations can be made.