CPAP Therapy Through a Helmet or a Full Face Mask in Patients With Acute Hypoxemic Respiratory Failure: Cross-over Study

In December 2019, an outbreak of a novel coronavirus emerged in Wuhan, China and rapidly spread worldwide. The World Health Organization (WHO) declared the outbreak a pandemic on March 11th, 2020. The clinical disease (COVID-19) results in critical illness in about 5% of patients with predominant acute respiratory failure. Observational and randomized trials have demonstrated the high effectiveness of non-invasive helmet ventilatory support, demonstrating a reduction in intubation rate mortality compared with high-flow and standard oxygen therapy. Some pilot physiological studies have shown physiological benefits of helmets compared to the oronasal mask for non-invasive ventilation. The purpose of the study is to compare markers of patient self-inflicted lung injury (P-SILI) (measuring esophageal pressure, transpulmonary pressure during inspiration and expiration), the patient's work of breathing (assessment of accessory muscles work) patient's comfort by visual-analog scale, gas exchange (by PaO2/FiO2 and Respiration Oxygenation Index (ROX-index), and hemodynamics in patients with acute hypoxemic respiratory failure (AHRF) during non-invasive pulmonary ventilation (NIV) in continuous positive pressure (CPAP) mode during an oronasal mask ventilation or a combination of a helmet with high-flow oxygenation as an air flow generator.