COVID-19 patients with severe acute pneumonia hospitalized in the ward before requiring ICU admission Positive PCR test result Respiratory rate ≥30 per minute Oxygen saturation ≤ 93% Fraction of inspired oxygen (FIO2) ≤ 300 mmHg Progression of lung lesions by more than 50% within 24-48 hours in the chest CT-scans 30 to 70-year-old men and women

COVID-19 patients with severe acute pneumonia hospitalized in the ward before requiring ICU admission Positive PCR test result Respiratory rate ≥30 per minute Oxygen saturation ≤ 93% Fraction of inspired oxygen (FIO2) ≤ 300 mmHg Progression of lung lesions by more than 50% within 24-48 hours in the chest CT-scans 30 to 70-year-old men and women