Positive effects of early continuous positive airway pressure on pulmonary function in extremely premature infants: results of a subgroup analysis of the COIN trial

OBJECTIVE: Early continuous positive airway pressure (CPAP) may reduce lung injury in preterm infants. PATIENTS AND METHODS: Spontaneously breathing preterm infants were randomised immediately after birth to nasal CPAP or intubation, surfactant treatment and mechanical ventilation. Pulmonary function tests approximately 8 weeks post-term determined tidal breathing parameters, respiratory mechanics and functional residual capacity (FRC). RESULTS: Seventeen infants received CPAP and 22 mechanical ventilation. Infants with early CPAP had less mechanical ventilation (4 vs 7.5 days; p=0.004) and less total respiratory support (30 vs 47 days; p=0.017). Post-term the CPAP group had lower respiratory rate (41 vs 48/min; p=0.007), lower minute ventilation (223 vs 265 ml/min/kg; p=0.009), better respiratory compliance (0.99 vs 0.82 ml/cm H(2)O/kg; p=0.008) and improved elastic work of breathing (p=0.004). No differences in FRC were found. CONCLUSIONS: Early CPAP is feasible, shortens the duration of respiratory support and results in improved lung mechanics and decreased work of breathing.