RDW:MCHC as a Pragmatic Adjunct to SOFA Score in ICU Mortality Assessment

Critical illness represents a complex pathophysiological state characterized by systemic inflammation, oxidative stress, immune dysregulation, and progressive multiorgan dysfunction. In the Intensive Care Unit (ICU) setting, accurate and timely risk stratification remains paramount for optimizing patient outcomes, guiding therapeutic decision-making, and ensuring appropriate allocation of limited healthcare resources .Red cell distribution width (RDW), a quantitative measure of anisocytosis, has emerged as a powerful independent predictor of adverse outcomes across diverse clinical contexts, including sepsis, cardiovascular disease, and general ICU populations . Elevated RDW reflects dysregulated erythropoiesis and is mechanistically linked to chronic inflammation, oxidative stress, nutritional deficiencies, and impaired hematopoietic progenitor cell function .Mean corpuscular hemoglobin concentration (MCHC) represents the average hemoglobin concentration within erythrocytes and provides valuable information regarding red blood cell integrity, hemoglobin synthesis, and oxygen-carrying capacity. Reduced MCHC values are observed in conditions associated with impaired hemoglobin production, while elevated values may indicate hemolysis or red cell dehydration .Emerging evidence suggests that composite hematological ratios may enhance predictive performance compared to individual parameters by integrating complementary physiological information. The RDW:MCHC ratio is a novel biomarker that combines variability in red cell size with hemoglobin concentration, potentially offering a more comprehensive reflection of the underlying pathophysiological derangements characteristic of critical illness