Benefits of Liquid Oxygen in COPD Patients Presenting Desaturation During Exercise.

Oxygen will be administered through nasal cannulae. Patients will be provided with a tank of liquid oxygen and a rechargeable portable device. The 6 minuts walking test will be used to adjusted oxygen flow in the GFA group (to achieve a mean SpO2 ≥ 90%). In the control group (GC), a 3L/min oxygen flow will be administer. Oxygen is used when the patient perform physical activity. The treatment period for each patient is 6 months (3 months in the GC grup, 3 months in the GFA one).