This rapid synthesis address the following questions: In patients with COVID-19 and acute hypoxemic ventilatory failure: • What is the effectiveness of administering high oxygen flows (> 15 L / min) to decrease the rate of admission to the Intensive Care Unit (ICU), the need for orotracheal intubation (OTI), and mortality? • What is the effectiveness of administering positive pressure on the airway to decrease the rate of admission to ICU, the need for OTI, and mortality? • What mechanism of high-flow oxygen therapy with or without positive pressure can be safer to reduce intrahospital infection transmission between patients and healthcare staff?