The main manifestation of COVID-19 is acute hypoxemic respiratory failure (AHRF). In patients with AHRF, the need for invasive mechanical ventilation is associated with high mortality.~Two hypotheses will be tested in this study. The first hypothesis is the benefit of corticosteroid therapy on severe COVID-19 infection admitted in ICU in terms of survival.~The second hypothesis is that, in the subset of patients free of mechanical ventilation at admission, either Continuous Positive Airway Pressure (CPAP) or High-Flow Nasal Oxygen (HFNO) allows to reduce intubation rate safely during COVID-19 related acute hypoxemic respiratory failure.~The main objective is to assess the impact of dexamethasone on overall mortality at day-60 after randomization in patients admitted in ICU for severe COVID-19 infection.~In non mechanical ventilation (MV) patients, the additional objective is to assess whether oxygen support based on either HFNO or CPAP modality in COVID-19 related AHRF reduces the need for mechanical ventilation at day-28.~An ancillary study CACAO (COVIDICUS air contamination) will be performed in 4 centers aiming at assessing the environmental contamination by SARS-CoV-2 according to the oxygen support modality. Additional funding will be searched for these analyses (submitted for ANR call).~A metanalysis on individual data will be performed using patients enrolled in the 3 PHRC flash exploring the activity of corticosteroids.
The main manifestation of COVID-19 is acute hypoxemic respiratory failure (AHRF). In patients with AHRF, the need for invasive mechanical ventilation is associated with high mortality.~Two hypotheses will be tested in this study. The first hypothesis is the benefit of corticosteroid therapy on severe COVID-19 infection admitted in ICU in terms of survival.~The second hypothesis is that, in the subset of patients free of mechanical ventilation at admission, either Continuous Positive Airway Pressure (CPAP) or High-Flow Nasal Oxygen (HFNO) allows to reduce intubation rate safely during COVID-19 related acute hypoxemic respiratory failure.