Study of Long-term HFNC for COPD Patients with HOT

Subjects will receive nocturnal high-flow nasal cannula therapy with the myAIRVO2®, in addition to their current Home oxygen therapy (HOT). The myAIRVO2® is used for at least 4 hours per day with flow rates in the range 30-40 L/min. The investigator can adjust the nocturnal oxygen flow rates to keep SpO2 88-92% stably. If the subjects report discomfort, the investigator can adjust the flow rates in the range at least 20 L/min.

All subjects will continue their current Home oxygen therapy (HOT) which kept original usage conditions at the time of enrollment throughout the entire duration of the study regardless of treatment arm assignment.