Fig. 4
Airway pressure wave detected using a ventilator sensor during the respiratory resistance measurement. Airway pressure including oscillation pressure is shown. The ventilator settings were as follows: respiratory rate: 10/min, inspiratory/expiratory ratio: 0.5, and inspiratory pause time/total inspiratory time ratio: 10%. Gray zones represent the inspiratory phase. Respiratory resistance could not be detected in the first 0.4 s of the expiratory phase because high airway pressure (> 4 cmH2O) prevents detecting respiratory resistance