Oxygen therapy via high flow nasal cannula in severe respiratory failure caused by Sars-Cov-2 infection: a real-life observational study oleh Giada Procopio, Anna Cancelliere, Enrico Maria Trecarichi, Maria Mazzitelli, Eugenio Arrighi, Graziella Perri, Francesca Serapide, Corrado Pelaia, Elena Lio, Maria Teresa Busceti, Maria Chiara Pelle, Marco Ricchio, Vincenzo Scaglione, Chiara Davoli, Paolo Fusco, Valentina La Gamba, Carlo Torti, Girolamo Pelaia