The objective of this prospective observational study is to describe the epidemiological, clinical and biological characteristics of admitted patients in ICU for severe acute exacerbation of COPD, to assess the different therapeutics used, to evaluate the prognosis of patients with short, medium and long term ( 1 year) and the various factors associated with survival in ICU

This is a prospective study for which data will be collected from pseudonymised. General information on the research activity clinic of the Intensive Care Service of the CH of Versailles is provided by poster, patient booklet or debrief hospitalization, indicating to relatives and/ or patients their possible participation in retrospective or prospective studies.

This research is conducted in accordance with the reference methodology MR 004 approved by the National Commission of Informatics and Libertés (CNIL) and to which the Centre hospitalier de Versailles is committed to comply. For this purpose, an information note will be given to each patient participating in this project in order to seek its non-opposition of participation in this study.

This prospective study is based solely on the examination of files medical. The data collected are only non-sensitive medical data.

This study complies with legal and regulatory requirements. In addition, this research project was submitted to the Ethics Committee (EC) of the Société de Réanimation de Langue Française (SRLF) who gave an opinion favorable on 06/10/2022 (Registration number referenced: CE SRLF 22- 056).

Inclusion Criteria:

1. Age ≥ 40 years old

2. COPD documented or strongly suspected

   • Chronic respiratory symptoms (dyspnoea, cough and/or sputum)
   • Exposure to a known risk factor for COPD (such as tobacco smoke)
   • If available, respiratory function tests showing non- or partially reversible obstructive syndrom (post-bronchodilator ratio FEV1/CV < 0.7)

3. Severe acute exacerbation, defined as a worsening of the patient's usual respiratory symptoms with signs of acute respiratory distress (polypnoea ≥ 30 cycles.min-1 or use of accessory respiratory muscles) and/or hypercapnic acidosis (with PaCO2 ≥ 45 mmHg and pH ≤ 7.35)

4. Admission to an ICU, a step-up unit or a respiratory care unit

Exclusion Criteria:

1. Known asthma (according to the criteria of the international "Global initiative for asthma" guidelines)
2. Patient refusal to participate (information note, application for non-opposition)

patients with severe acute exacerbation of COPD admitted in ICU