Gulczyńska E, et al. - Since there are limited data available regarding the fraction of inspired oxygen (FiO₂) predictive of the failure of continuous positive airway pressure (CPAP) in preterm infants with respiratory distress syndrome (RDS), therefore, researchers conducted this multicenter, prospective study to examine factors predictive of CPAP failure in the first 72 h of life, with particular attention to the prognostic role of FiO₂. Of the 389 newborns recruited, 108 infants had CPAP failure. The risk for each 0.01 increase in FiO₂ in the first and second hours of life was increased by 4.2 and 7.5%, respectively. CPAP failure implied a more than 20-fold increased risk of death and pneumothorax and a 2- to 5-fold increased risk of typical premature complications, including bronchopulmonary dysplasia and severe intraventricular hemorrhage. According to findings, FiO₂ is a significant predictor of CPAP failure in the second hour of life. Data reported that the threshold of 0.29 best discriminates the CPAP outcome. CPAP nonresponders have a significantly higher complications incidence and a higher mortality rate.