Tolerance and Acute Effects of a New HFNT Nasal Cannula

The AIRVO 2 is a humidifier with integrated flow generator that delivers warmed and humidified respiratory gases to spontaneously breathing patient through a variety of patient interfaces. This is an FDA-approved 510k device for use in hospitals and nursing homes. During HFNT, oxygen will be passed through a heated humidifier (AIRVO 2, Fisher and Paykel Healthcare) and applied continuously through conventional large-bore binasal symmetric prongs or the new asymmetric prongs cannula device, with a gas flow rate of 20-35 liters per minute or as high as the patient will tolerate and an FiO2 to keep SaO2 ≥ 90% (Airvo 2, Fisher and Paykel Healthcare). Gas flow temperature will be adjusted based on patient's comfort and range from 34-37 degrees centigrade. After completion of the study, patients will be switched back to oxygen therapy administered by nasal prongs or mask..