Comparing NIRS and Pulse Oximetry for Cerebral Oxygen Saturation During Hypoxia Testing

Area of Science:

• Aerospace Medicine
• Physiological Monitoring
• Medical Devices

Background:

• Hypoxia poses significant risks during flight operations and training.
• Accurate monitoring of cerebral oxygen saturation is crucial for aviation safety.
• Traditional pulse oximetry (SpO2) may have limitations in detecting critical hypoxic events.

Purpose of the Study:

• To evaluate the suitability of cerebral oximetry using near-infrared spectroscopy (NIRS) against pulse oximetry (SpO2) for hypoxia testing.
• To determine the reliability and stability of NIRS for measuring cerebral oxygen saturation (rSO2) in aviation environments.
• To assess the potential of NIRS to enhance safety during flight operations and training.

Main Methods:

• 100 participants underwent hypoxia testing at 25,000 feet.
• Cerebral oxygen saturation (rSO2) was measured using NIRS (INVOS™ 5100C).
• Peripheral oxygen saturation (SpO2) was measured using pulse oximetry (Masimo™ MS5).
• Data analyzed using regression, Bland-Altman plots, and concordance correlation coefficients (CCC).

Main Results:

• NIRS measurements (rSO2) were more stable and less prone to disruptions than pulse oximetry (SpO2) during hypoxia.
• Pulse oximetry experienced 95 disruptions, 25 potentially critical, while NIRS showed minimal right-left deviations.
• Lin's CCC indicated moderate to substantial concordance between NIRS and SpO2, with NIRS providing higher values during hypoxia.

Conclusions:

• Near-infrared spectroscopy (NIRS) is a reliable method for detecting cerebral oxygen saturation during hypoxia.
• NIRS offers significant advantages in stability and reliability over traditional pulse oximetry for hypoxia testing.
• NIRS supports continuous monitoring in aviation, enhancing flight safety through more accurate hypoxia detection.