Effect on lung function of continuous positive airway pressure administered either by infant flow driver or a single nasal prong

The aim of this study was to assess if continuous positive airways pressure (CPAP) delivered by an infant flow driver (IFD) was a more effective metho d of improving lung function than delivering CPAP by a single nasal prong. A total of 36 infants (median gestational age 29 weeks, range 25-35 weeks) were studied, 12 who received CPAP via an IFD, 12 who received CPAP via a s ingle nasal prong and 12 without CPAP. CPAP was administered post extubatio n if apnoeas and bradycardias or a respiratory acidosis developed or electi vely if the infant was of birth weight <1.0 kg. Lung function was assessed by the supplementary oxygen requirement and measurement of compliance of th e respiratory system using an occlusion technique. Assessments were made im mediately prior to and after 24 h of CPAP administration and at similar pos tnatal ages in the non-CPAP group. The infants who did not require CPAP had better lung function (non significant) than the other two groups before th ey received CPAP. After 24 h, lung function had improved in both CPAP group s to the level of the non CPAP infants. The supplementary oxygen requiremen ts of all three groups decreased over the 24 h period, but this only reache d significance in the single nasal prong group (P < 0.05). Four infants sup ported by the IFD, but none with a single nasal prong, became hyperoxic. Conclusion Continuous positive airways pressure administration via the infa nt flow driver appears to offer no short-term advantage over a single nasal prong system when used after extubation in preterm infants.