Physiological consequences of rapid or prolonged aircraft decompression: evaluation using a human respiratory model

Area of Science:

• Aerospace Medicine
• Physiology
• Hypobaric Hypoxia Research

Background:

• Aircraft decompression events can expose passengers and crew to hypobaric hypoxia.
• Current neurological damage assessment relies on 'time of useful consciousness' (TUC), which is not ideal for passenger decompression scenarios.

Purpose of the Study:

• To propose and validate arterial oxygen saturation of 70% (S70) as a critical measure for hypobaric hypoxia in passengers.
• To establish S70 as a more suitable alternative to alveolar O2 pressure (P30) for passenger decompression assessment.

Main Methods:

• Utilized a model to predict physiological measures during decompression scenarios.
• Evaluated the equivalence of predicted P30 and S70 values in established decompression models.
• Applied the model to predict P30 and S70 in actual aircraft decompression scenarios.

Main Results:

• Demonstrated the equivalence between model-predicted P30 and S70 values in Ernsting-decompression scenarios.
• Successfully predicted P30 and S70 values for real-world aircraft decompression events using the developed model.

Conclusions:

• The developed model enables quantitative prediction of hypobaric hypoxia for diverse decompression scenarios, including those with supplemental oxygen.
• This tool eliminates the need for costly and dangerous human-subject testing in aircraft development.
• Provides a safer and more accurate method for assessing passenger risk during in-flight decompressions.