1243: Beyond the Numbers: Unlocking Prognosis With Lactate to Albumin Ratio in Critically Ill Children

Introduction: The lactate-to-albumin ratio (LAR) integrates markers of metabolic stress and systemic inflammation, which cause poor outcomes in pediatric critical illness. While international studies support its prognostic value, no local data exist from Pakistan. This study evaluated the association between LAR and clinical outcomes in critically ill children and aimed to identify a population-specific threshold for predicting mortality. Methods: We conducted a prospective cohort study at the Aga Khan University Hospital PICU between April 2024 and April 2025. Critically ill children aged 1 month to 18 years were enrolled (N=249) if both lactate and albumin levels were measured within 24 hours of admission. Patients with early albumin infusion, chronic illness, or incomplete records were excluded. The primary outcome was in-hospital mortality. Secondary outcomes included multi-organ dysfunction syndrome (MODS), duration of mechanical ventilation, PICU length of stay, and Vasoactive Inotropic Score (VIS). An initial reference LAR cut-off of 0.5 was tested, followed by ROC analysis to derive an optimal threshold. Results: At the reference cut-off (>0.5), patients had higher mortality (30.3% vs. 5.9%) and MODS (60.1% vs. 21.6%). ROC analysis (AUC=0.83) identified a more accurate cut-off of 0.79. At LAR >0.79, mortality rose to 47.8% vs. 6.0%, MODS to 84.3% vs. 24.6%, with significantly longer PICU stays and ventilation duration. The derived cut-off improved sensitivity (48%) while maintaining high specificity (94%). All associations were statistically significant (p< 0.001). Conclusions: LAR is a simple, accessible predictor of mortality and morbidity in critically ill children. A threshold of 0.79 improves accuracy over conventional cut-offs. Integration into risk stratification protocols is recommended, pending multicenter validation.