Background Nasal continuous positive airway pressure (NCPAP) can be applied via binasal prongs or nasal masks; both may be associated with air leak and intermittent hypoxia. We investigated whether the latter is more frequent with nasal masks or prongs.

Methods Continuous 24 hours recordings of inspired oxygen fraction (FiO₂), pulse rate, respiratory rate, pulse oximeter saturation (SpO₂) and CPAP level were made in preterm infants with respiratory insufficiency (n=20) managed on CPAP in the NICU at the Royal Hobart Hospital. As part of routine care, nasal interfaces were alternated 4-hourly between mask and prongs. In each recording, the first two segments containing at least 3 hours of artefact-free signal for each interface were selected. Recordings were analysed for episodes with hypoxaemia (SpO₂ <80% for ≥10 s) and bradycardia (pulse rate <80/min for ≥4 s) and for episodes of pressure loss at the nasal interface. Data were compared using Wilcoxon-matched pairs test and are reported as median (IQR).

Results Infants had a gestational age at birth of 26 (25-27) weeks and postnatal age of 17 (14–24) days. There was no difference in %time with interface leak between prong and mask (0.9 (0–8)% vs 1.1 (0–18)%, p=0.82), %time with SpO₂ <80% (0.15 (0–1.2)% vs 0.06 (0–0.8)%, p=0.74) or heart rate <80/min (0.03 (0–0.2)% vs 0 (0–0.2)%, p=0.64). Three infants had interface leak for >10% of the time with prongs and 5 with the mask.

Conclusion Both interfaces resulted in a similarly stable provision of positive airway pressure, and there was also no difference in the occurrence of intermittent hypoxia.