Preoxygenation: a comparison of three different breathing systems

Area of Science:

• Anesthesiology
• Respiratory Medicine
• Medical Devices

Background:

• Adequate preoxygenation, defined as an end-tidal expiratory oxygen concentration (FE'O2) > 0.90, is crucial for patient safety.
• Traditional face mask preoxygenation can be unsatisfactory for some individuals.
• Novel devices aim to improve preoxygenation efficacy and patient comfort.

Purpose of the Study:

• To compare the efficacy and patient acceptance of preoxygenation using a face mask, a mouthpiece with a nose-clip, and the novel NasOral system.
• To evaluate key preoxygenation metrics including maximal FE'O2, FE'O2 after 2 minutes, and time to maximal FE'O2.

Main Methods:

• A randomized controlled study involving 30 healthy volunteers.
• Comparison of three preoxygenation methods: face mask, mouthpiece with nose-clip, and modified NasOral system.
• Objective measurements of FE'O2 and subjective patient ratings were recorded.

Main Results:

• Both face mask and mouthpiece achieved significantly higher maximal FE'O2 compared to the NasOral system (P<0.05 and P<0.01).
• A FE'O2 of 0.90 was reached in 73% of participants with face mask/mouthpiece versus 46% with NasOral.
• The mouthpiece demonstrated a significantly higher FE'O2 after 2 minutes (P<0.01) and faster time to maximal FE'O2 than the other devices.

Conclusions:

• Mouthpiece preoxygenation offers improved efficacy and potentially faster oxygenation compared to face masks and the NasOral system.
• The modified NasOral system demonstrated inferior performance and patient acceptance, not supporting its clinical adoption.
• Mouthpiece use may be a valuable alternative for enhancing preoxygenation in specific patient populations.