All patients referred to our centre of oxygen titration during exertion will be offered to participate in our study.
After baseline assessments, patients will have an oxygen titration using two different methods in random order:
* Usual titration protocol will include an manual oxygen increase during a titration 6 minutes walk test
* Automatic titration protocol that will use the automated oxygen titration device to adjust oxygen flow rate during a titration 6 minutes walk test.
After each titration protocol, the efficacy of the titration will be assessed in 3 validation 6 minutes walk tests during which oxygen flow will be set at:
* The manually determined flow rate
* The 95th percentile flow rate of the automatic titration
* The median flow rate of the automatic titration
During validation 6 minutes walk test, oxygen saturation, dyspnea, walked distance and heart rate will be recorded.
