A Novel, Inexpensive Method to Monitor, Record, and Analyze Breathing Behavior During Normobaric Hypoxia Generated by the Reduced Oxygen Breathing Device.

Objectives: Since hypoxia remains one of the most important physiological hazards the aviation environment poses, military aviators are trained to recognize symptoms of hypoxia in order to implement appropriate safety procedures and countermeasures when hypoxia occurs. A widely used commercial instrument for hypoxia training, demonstration, and research is the Reduced Oxygen Breathing Device (ROBD). Here we describe a novel, inexpensive method to use the ROBD's breathing loop pressure (BLP) to measure respiration rate, a critically important response parameter for hypoxia.

Methods: The ROBD can be controlled by a computer to export several variables including BLP, via the ROBD's RS232 port. An archived database was reanalyzed to assess the BLP data. New instrumentation added independent measures of respiration and expired oxygen and carbon dioxide; these measures were integrated with the ROBD output.

Results: Analysis of the archived data showed that the BLP reflected realistic breathing patterns. The new instrumentation integrated well with the ROBD, and independently supported the potential of the BLP as a valid measure of respiration.

Discussion: The ROBD's BLP data may provide a basis for a reliable, sensitive measure of respiration that is available at no additional cost.