Utility of High Flow Nasal Cannula during Pulmonary Rehabilitation in COVID-19 Patients in Acute Respiratory Failure

High-flow nasal cannula (HFNC) has often been used in the treatment of acute respiratory failure during pulmonary rehabilitation setting. The aim of this retrospective study was to investigate the utility of HCFN during the early rehabilitation in COVID-19 pneumonia. Twenty-two patients (10 males and 12 females, mean age 64.5 +/- 5.9 years) with COVID-19 pneumonia were considered. Medical data and rehabilitative scales were used to evaluate acute hypoxemic respiratory failure (PaO2/FiO2 < 300), treated with HFNC three times during evaluation. Overall clinical outcomes from the evaluation of the synergy between HFNC strategy and rehabilitation were evaluated. A statistically significant improvement was observed at T2 (and of treatment) in 1 minute sit to stand test (1STST) (4 +/- 3 vs. 17 +/- 5, p < 0.05), short physical performance battery (SPPB) (4.3 +/- 2.81 vs. 9.15 +/- 2.39, p < 0.05), SpO2% post effort (93 +/- 1.26 vs. 98 +/- 1.01, p < 0.05), respiratory rate post effort (RR) (24 +/- 3.91 vs. 20 +/- 3.13, p < 0.05), heart rate (HR) (97 +/- 11.9 vs. 87 +/- 9.17, p < 0.05), P/F rate (235 +/- 7.35 vs. 331 +/- 10.91, p < 0.05), SpO2 (86 +/- 4.54 vs. 97 +/- 1.01 p < 0.05), RR (20 +/- 4 vs. 12 +/- 1.39, p < 0.05). Then, treated HFNC patients showed a good improvement in physical performance at T2 and a good compliance with treatments proved to be extremely useful in the control and reduction of dyspnea and fatigue symptoms.