Exercise Capacity Under Various FiO2 and Oxygen Flow Rates Using HFNC

The nasal high flow therapy has enabled high flow oxygen to be derived through nasal cannula. This mode not only allows constant FiO2 during peak inspiratory flow but also confers benefits including a low level of continuous positive airway pressure with increased end-expiratory lung volume and reduced work of breathing, partly through intrinsic positive end-expiration pressure compensation and dead space washout. The inspired gases are warmed and humidified, improving comfort and possibly reducing airway inflammation, leading to improved drainage of respiratory secretions.