The NuMask® is as Effective as the Face Mask in Achieving Maximal Preoxygentation

Background: Preoxygenation before anesthetic induction is a widely accepted maneuver to increase oxygen reserves and delay desaturation during apnea. There is limited data regarding the use of the NuMask® in the perioperative setting, and no data as to its efficacy in achieving maximal preoxygenation. We hypothesize that the NuMask® may be a useful alternative to the face mask in achieving maximal preoxygenation. Methods: After IRB approval, the NuMask® was compared with the classic face mask with respect to achieving maximal pre-oxygenation in 30 healthy volunteers using tidal volume breathing. All volunteers were tested for three periods of 5 minutes intervals and the following parameters were recorded every 30 seconds: inspired, and end-tidal oxygen concentration and endtidal carbon dioxide concentration. Results: The mean ETO2 of ≥90% was achieved with both masks at 3.5 minutes (SD = 1.62 and 1.98 for facemask and NuMask® respectively) and thereafter the ETO2 remained above 90%. There were no statistical differences noted in FiO2 and ETO2 between the face mask and the NuMask® in the same time periods. ETCO2 values were also not statistically different between the two masks. Conclusions: The study showed that the NuMask® is as effective as the classic face mask in achieving maximal pre-oxygenation during tidal volume breathing. Introduction