Background : Acute exacerbations of COPD (Chronic Obstructive Pulmonary Disease) are frequent events in the course of the disease and they can deteriorate the respiratory function of the patients, impact their quality of life and even potentially threaten their life. It is therefore crucial to prevent these exacerbations from occurring.

Aim of the study : Investigate how cardiorespiratory parameters of COPD patients differ between exacerbation phases and their nominal state in order to identify predictors of COPD exacerbations.

Study design : Patients admitted at one of the investigation centers on a suspicion of COPD exacerbation will be enrolled on a voluntary basis. Enrolled patients' cardiorespiratory parameters will be monitored with a connected wrist-worn pulse oximeter (BORA Band) during the hospitalisation phase and one month after they have been discharged.

Setting : 4 investigative centers across Brittany

Patients : 50 patients will be enrolled in the study

Inclusion Criteria:

• patient known or suspected to suffer from COPD
• patient admitted in pulmonology unit for COPD exacerbation
• patient accepting to use BORA Band during and after hospitalization
• patient accepting to be followed by the partner health care provider for this study (Air de Bretagne)
• patient able to understand French and express their informed consent
• patient affiliated to social security

Exclusion Criteria:

• patient is intubated
• patient already followed by a health care provider other than Air de Bretagne
• investigator assesses that the patient will have difficulties following the protocol
• patient already enrolled in another interventional study