Oxygenation and Carbon Dioxide Rebreathing of a Well-fitting Non-rebreathing EcoLite™ Mask with a Reservoir: A Single-center Prospective Observational Study in Healthy Volunteers

Background: The fitting of oxygen mask affects the performance of it such as oxygenation or CO₂ elimination. The intersurgical EcoLite™ adult high-concentration oxygen mask (EcoLite with a reservoir, Intersurgical, UK) was developed to give well-fitting. The purpose of this study is to evaluate the performance of EcoLite with a reservoir compared to the conventional mask.

Methods: Ten healthy volunteers were included in this study. EcoLite with a reservoir and conventional mask were given to patients at different oxygen flow rates (5, 8, 10, 12, and 15 L/min). Fraction of inspiratory O₂ (F_IO₂) and partial pressure of inspiratory CO₂ (P_ICO₂) were measured by a sampling tube at the middle pharynx inserted via nose.

Results: The EcoLite with a reservoir had a significantly higher F_IO₂ than the control reservoir mask. However, the P_ICO₂ was significantly higher in the EcoLite with a reservoir than in the control reservoir mask, especially when the oxygen flow rate was low.

Conclusion: The EcoLite with a reservoir provided improved oxygenation and a better fit than the conventional reservoir masks in healthy volunteers. However, the EcoLite with a reservoir might cause higher CO₂ rebreathing at low oxygen flow rates.