inclusion criteria: - informed consent for participation in the study - virological diagnosis of sars-cov-2 infection (real-time pcr) - hospitalized due to clinical/instrumental diagnosis of pneumonia - oxygen saturation at rest in ambient air ≤94% - pao2/fio2 ratio of 350 to 200

inclusion criteria: - informed consent for participation in the study - virological diagnosis of sars-cov-2 infection (real-time pcr) - hospitalized due to clinical/instrumental diagnosis of pneumonia - oxygen saturation at rest in ambient air ≤94% - pao2/fio2 ratio of 350 to 200