Benchmarking Sepsis Severity: Evaluating Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) Scores Against Biomarkers, Comorbidities, and Outcomes in Rural Intensive Care Unit (ICU) Patients

Introduction: Sepsis and septic shock remain major contributors to morbidity and mortality in intensive care units (ICUs), with these challenges being amplified in rural settings, where limited resources and delayed access to specialized care can affect patient outcomes.The Acute Physiology and Chronic Health Evaluation II (APACHE II) score and the Sequential Organ Failure Assessment (SOFA) score are currently considered crucial tools for assessing illness severity.However, comparative analyses linking these scores to specific clinical variables in rural ICUs remain scarce.Objective: This study evaluates the relationships between APACHE II and SOFA scores and a broad range of clinical parameters in septic ICU patients.Associations with demographic characteristics, comorbidities, inflammatory markers of sepsis (CRP, WBC count, and PCT), lactate levels, vasopressor requirements, and 28-day mortality were examined, with particular attention to factors influencing score performance in resource-limited rural settings.Method: A retrospective review of adult patients admitted with sepsis and septic shock to the ICU of Hatta Hospital over a five-year period (2021-2025) was conducted.Data were analyzed using correlation testing, regression models, and receiver operating characteristic (ROC) curve analysis.Results: Day 1 lactate levels and vasopressor use had the highest predictive values for 28-day mortality.Their ability to discriminate between survivors and non-survivors was assessed using the area under the curve (AUC), which was 0.74 for day 1 lactate levels and 0.81 for vasopressor use.Meanwhile, PCT, CRP, and WBC counts demonstrated poor discriminatory ability.Non-survivors had higher day 1 lactate levels (5.08 ± 4.41 mmol/L; 95% CI: 4.03-6.13)than survivors (2.26 ± 1.71 mmol/L; 95% CI: 2.01-2.51;p < 0.001).Vasopressor use demonstrated a sensitivity of 83.8%, specificity of 78.1%, positive predictive value (PPV) of 59.4%, negative predictive value (NPV) of 92.7%, and an AUC of 0.810.Conclusion: Higher lactate levels within the first 24 hours and vasopressor use showed highly significant associations with 28-day mortality.PCT, CRP, and WBC counts demonstrated no significant associations.Our findings support the use of APACHE II and SOFA scores, together with these readily available and straightforward clinical variables, for early risk stratification and prognostic assessment, particularly in resource-limited and rural ICUs.