Inclusion Criteria:  The diagnosis of a current SARS-CoV2 infection (confirmed RT-PCR test or antigen test [allowed in Poland, with sensitivity ≥90 and specificity ≥97]); Hospitalization in the Oxygen Sector of the Temporary Hospital in Szczecin; Pneumonia during SARS-CoV2 infection; ARDS (PaO 2 / FiO 2 ratio ≤300); Oxygen flow 8-12 l / min on mask with reservoir and ≤ 60 mmHg paO2 and / or SpO2 < 92%; TNo current indications for treatment in the ICU; Permisson of the patient.  Exclusion Criteria:  Probable lack of cooperation with patient; Severe Disease disease, eg generalized neoplastic disease; Concomitant pulmonary diseases (eg, fibrosis lungs); Respiratory acidosis - pH <7.3 with pCO2> 50 mmHg; Disturbances of consciousness - GCS < 12;