Admission Respiratory Rate-Oxygenation Index and Outcome of Acute Respiratory Illness in a Pediatric Intensive Care Unit.

Background Acute respiratory illness (ARI) remains a leading cause of pediatric intensive care unit (PICU) admissions and mortality in low- and middle-income countries. Early identification of children at risk of deterioration or ventilatory support is essential to improve outcomes. The Respiratory Rate-Oxygenation (ROX) Index, defined as (peripheral oxygen saturation (SpO₂)/fraction of inspired oxygen (FiO₂))/respiratory rate, is a non-invasive bedside tool validated in adults with respiratory failure; however, pediatric evidence is scarce. Objectives To evaluate the association of admission ROX Index with (1) mortality and (2) the requirement for positive-pressure ventilation (PPV) among children with ARI admitted to the PICU. Methods A prospective observational study was conducted among 200 consecutively admitted children aged two months to five years with ARI at a tertiary-care hospital. Demographic, anthropometric, and physiological parameters were recorded at admission. The ROX index was computed as (SpO₂/FiO₂)/respiratory rate. Primary outcomes were in-hospital mortality and need for PPV. Data were analyzed using non-parametric tests and receiver operating characteristic (ROC) analysis;