Hospitalized patients with COVID-19 typically present with hypoxemia. In some patients, hypoxemia can be corrected with low flow nasal cannula. When placed above nasal cannula, some systems have demonstrated their interest in improving the performance of patient's oxygen delivery. For example, two recent studies have shown that adding a Double-Trunk Mask (DTM) or Surgical Mask (SM) above nasal cannula has the potential to improve the PaO2 despite no change in oxygen output (Duprez et al., J Clin Monit Comput 2020; Montiel et al., Ann Intensive Care 2020). However, there is no study comparing the relative effectiveness of these 2 systems.
This study will compare the impact of two systems above low-flow nasal cannula on the arterial oxygen tension in patients with COVID-19. The two systems are the Surgical Mask (SM) and the Double-Trunk Mask (DTM).