The Role of Gas Flow in Transnasal Pulmonary Aerosol Delivery: A Double-blinded, Randomized Controlled Trial

High flow nasal cannula (HFNC) is a relatively new oxygen device, which provides warmed and humidified oxygen for patients. When patients need to inhale aerosolized medication during HFNC, the nebulizer will be placed in-line in order to provide both treatments. This study will investigate the influence of three flow settings (50 L/min, GF:IF=1, GF:IF=0.5) on the clinical effects of nebulization.