A Single-center, Prospective, Cross-over Study to Compare the Efficiency of Oxygen Supply between the OxyMask TM and Non-rebreather Mask in Healthy Adults

Purpose: In this single-center, prospective, randomized, cross-over study, we compared the efficiency of oxygen supply between OxyMask and non-rebreather mask (NRM), depending on the position of the mask. Methods: Either OxyMask or NRM was applied to 33 healthy volunteers, in a random manner, on the upper (that 1 cm upper to it), lower (that 1 cm inferior to it) and lateral malposition (that 1 cm lateral to it). After a 3-minute oxygenation, at a flow rate of 15 L/min, we measured the fractional expired oxygen concentration (FEO2), fractional expired carbon dioxide concentration (FECO2), and visual analogue scale (VAS) scores for the degree-of-wearing sensation. Results: OxyMask showed a lower level of FEO2 as compared with NRM in all positions. Moreover, OxyMask showed no significant difference between FEO2 and the position of the mask. However, NRM showed a significantly lower FEO2 in the upper and lateral malposition. FECO2 had no significant difference with the types and position of the mask. The mean VAS scores for the degree-of-wearing sensation were 2.2±1.5 in the OxyMask and 4.3±1.5 in the NRM (p<0.001). Conclusion: OxyMask may offer greater benefit in maintaining the concentration of supplied oxygen and provide greater comfort than NRM in patients with difficulty applying the mask on an adequate location and maintaining the seal.