RCT: In patients with severe Covid-19, high-flow oxygen therapy reduced the likelihood of invasive mechanical ventilation and decreased the time to clinical recovery compared to conventional oxygen therapy.

Effect of High-Flow Oxygen Therapy vs Conventional Oxygen Therapy on Invasive Mechanical Ventilation and Clinical Recovery in Patients With Severe COVID-19: A Randomized Clinical Trial – JAMA

Related:

Non-invasive respiratory support in the management of acute COVID-19 pneumonia: considerations for clinical practice and priorities for research – “The two randomized controlled trials indicate superiority of non-invasive ventilation over high-flow nasal oxygen in reducing the need for intubation”.

[Preprint] RCT: non-invasive respiratory strategies in acute respiratory failure in patients with COVID-19 – CPAP reduced the composite outcome of intubation or death within 30 days; high-flow nasal oxygenation was not associated with better outcomes.