Evaluation of the possibil ity to perform oxygen therapy with a bag valve mask with reservoir

Abstract

Introduction. Inhalation of supplemental oxygen is an important treatment modality for patients in critical condition. Non-rebreather mask with a reservoir is used to maintain a high oxygen concentration in the airway, due to presence of one-way valves system. The bag valve mask (Ambu bag) has a structurally similar valve system and reservoir. Objective of the study. Comparing of volumetric concentrations of oxygen in the respiratory tract during oxygen inhalation through a non-rebreathing mask with a reservoir and through an bag-valve mask with a reservoir. Materials and methods. In 22 volunteers, oxygen was inhaled through a non-rebreathing mask with a reservoir and with a bag-valve-mask with a reservoir. The volumetric concentration of oxygen in exhaled air was measured after 3 minutes of inhalation. The data were compared with the initial level of oxygen concentration in exhaled air, as well as with the data after inhalation through an oxygen cannula. Results. The oxygen concentration maintained in airway during inhalation with a bag-valve-mask with a reservoir is comparable to concentration after inhalation through a non-rebreathing mask with a reservoir, 62.42±14.58% and 57.22±11.18%, respectively (p=0.19). After performing correlation analysis, a positive relationship was found between the volume concentration of oxygen in exhaled air during inhalation through a non-rebreathing mask with a reservoir and through a bag-valve mask with a reservoir (r=0.28; p=0.05). Conclusion. Inhalation of supplemental oxygen via a bag-valve mask with reservoir may be a reasonable solution when a non-rebreathing mask with a reservoir is not available in low-resource settings, such as a mass casualty incident.