Humidity during high-frequency oscillatory ventilation compared to intermittent positive pressure ventilation in extremely preterm neonates: An in vitro and in vivo observational study.

RH was significantly lower during HFOV than IPPV, both in vitro and in vivo. The type of heater-humidifier also influenced humidification. More systematic measurements of humidity of inspired gas, especially during HFOV, should be considered to optimize humidification and consequently lung protection in ELBW infants.