Inspired oxygen fraction thresholds to accurately predict surfactant administration in neonatal RDS is gestational age strata: A pragmatic, multi-center study

Objective: Current international guidelines on neonatal respiratory distress syndrome (RDS) recommend continuous positive airway pressure (CPAP) stabilization as primary treatment. Some guidelines recommend surfactant replacement for babies requiring FiO2 > 0.3 regardless of gestational age (GA). We explore the accuracy of alternative inspired oxygen fraction (FiO2) thresholds as early predictors of surfactant replacement in babies stratified by GA. Study Design: Pragmatic, observational study in 12 Italian and Spanish neonatal intensive care units. This is a secondary analysis of data from two cohorts of preterm babies with RDS, stratified by GA (25°− 276; 28°−306; 31°−336) and stabilized on CPAP. FiO2 was collected soon after stabilization and its accuracy to predict subsequent surfactant administration by a rigorously masked physician was assessed. Results: We enrolled 412 preterm infants. FiO2 was collected within 2 h of life of life. A cut off of FiO2 > 0.30 failed to identify 50.3% of infants who were later given surfactant by a masked physician. A FiO2 = 0.29 threshold improved sensitivity values to 0.85, 0.79, and 0.61 for the three GA ranges while maintaining specificity of ≥85%. A FiO2 = 0.26 threshold gave sensitivity = 0.83 specificity = 0.79 with GA dependent differences (250−276 sensitivity = 0.90 specificity = 0.80; 280−306 sensitivity = 0.84 specificity = 0.78; 310−336 sensitivity = 0.73 specificity = 0.80). Conclusions: FiO2 is a GA dependent predictor of early surfactant administration. Its accuracy increases when used at lower levels than currently recommended by international guidelines (236 words).