Inclusion Criteria:  Adult intubated patients aged between 18 to 90 years Pass spontaneous breathing trial and receive the order to be extubated Have at least one of the indications to use HFNC after extubation  Exclusion Criteria:  Need to use inhaled epoprostenol via HFNC Pregnant Unable to use resuscitation mask, such as facial trauma, claustrophobia Non-English speaker Inability to verbally communicate Using extracorporeal membrane oxygenation (ECMO) Hemodynamically unstable Difficult airway