Acute respiratory distress syndrome (ARDS) is due to diffuse and severe lung inflammation. Despite intensive research, few therapeutics have emerged and treatment is still mostly symptomatic. As lung microbiota seems to be associated with lung inflammation in numerous chronic respiratory diseases, this study aims to analyse the correlation between lung microbiota and mortality.

ARDS is caused by diffuse intense lun inflammation. Its mortality rate is still about 40%. Despite decades of research, few therapeutics have emerged. Treatment is based on the treatment of ARDS cause, if possible and on protective ventilation, curare use and prone position. For more severe cases, nitric monoxide inhalation and extra-corporeal membrane oxygenation can be considered. Nevertheless, no treatment specifically addresses lung inflammation. Lung microbiota has been shown to be associated with lung inflammation in asthma, chronic obstructive disease and cystic fibrosis. Lung microbiota also plays a role in lung immunity. Regarding specifically ARDS, one study correlated lung microbiota with the occurrence of non-infectious ARDS in trauma patients. Thi study therefore aims to analyse the correlation between lung microbiota at admission to ICU for ARDS with mortality.

Inclusion Criteria:

• Patient above 18 year-old admitted to intensive care unit
• ARDS according to Berlin criteria
• Needing oro-tracheal intubation for mechanical ventilation
• Within the first 48 hours of ARDS evolution

Exclusion Criteria:

• Guardianship or curatorship
• Prisoners
• No health insurance
• No legal representative

ARDS patients needing oro-tracheal intubation for mechanical ventilation in ICU