Exploration of the VOLATOLOM in the Stable Severe COPD (Chronic Obstructive Pulmonary Disease)

After being informed about the study, all patients giving written informed consent and meeting the eligibility criteria will undergo 4 visits spaced 4 to 6 weeks apart. The first visit V1 will be about 45 minutes duration. The others ones (V2 to V4) will be about 30 minutes duration. All sessions will be carried out in the Pneumology Department of the Foch Hospital, volatolomics platform (Exhalomics®). Exhalation collection will be performed at each visit in order to perform the volatolom analysis.