Background: Preterm infants are increasingly using nasal continuous positive airway pressure (CPAP) immediately after birth as an initial respiratory support. Some infants managed with this modality ultimately fail on CPAP and require intubation and ventilation. Infants who fail CPAP are associated with a higher risk of adverse outcomes.
Objective: To identify the incidence, predictors and neonatal outcomes associated with the CPAP failure in preterm infants with respiratory distress syndrome (RDS).
Material and Method: Preterm infants of 25 to 32 weeks gestation with RDS receiving nasal CPAP as an initial respiratory support were included in the study. They were divided into two groups according to success or failure on CPAP in the first 72 hours of life. Predictors of CPAP failure were determined and outcomes between the two groups were compared.
Results: CPAP failure occurred in 18 of total 83 infants (22%). Which was more likely to occur at gestational ages of 25 to 28 weeks than at 29 to 32 (50% vs. 15%, p = 0.005). In multivariate logistic analysis, gestational age lower than 28 weeks, received positive pressure ventilation in the delivery room, required maximum FiO2 >0.5 and male gender were significantly associated with CPAP failure [adjusted odd ratio 8.53 (95% CI 1.94, 37.50), 3.56 (95% CI 0.83, 15.40), 3.28 (95% CI 0.72, 15.02) and 2.50 (95% CI 0.63, 9.89) respectively]. Infants who failing CPAP had higher mortality (adjusted odd ratio 45.5, 95% CI 2.78, 744.18) and adverse outcomes including BPD (adjusted odd ratio 1.5, 95% CI 0.34, 6.56) and NEC (adjusted odd ratio 1.8, 95% CI 0.18, 18.45) when controlled for gestation and presence of moderate to severe RDS on initial chest radiography.
Conclusion: CPAP failure in preterm infants with RDS usually occurs in those who are born very premature with moderate to severe RDS as indicated by requirement of maximum FiO2 >0.5 in the first hours of life.

Keywords: Preterm infants, Respiratory distress syndrome, Continuous positive airway pressure, Bronchopulmonary dysplasia