What is the purpose of positive pressure breathing in aviation medicine?

Positive pressure breathing is primarily employed in aviation medicine as a method for ensuring adequate oxygen intake during emergencies. In high-altitude situations, where the oxygen levels in the atmosphere are significantly reduced, relying on the body’s normal respiratory function may not provide enough oxygen for the pilot or passengers. Positive pressure breathing techniques involve using a device that delivers supplemental oxygen under pressure, which ensures that sufficient oxygen is available for proper physiological function even in challenging conditions.

This technique is particularly critical during situations such as rapid decompression or when flying at altitudes over 25,000 feet, where hypoxia can develop quickly. By delivering oxygen at a higher pressure than the surrounding atmosphere, it mitigates the risk of oxygen deprivation and allows pilots to maintain cognitive and physical performance, which is essential for safe flight operations. Hence, the correct answer underscores the importance of this method in emergency scenarios to protect against insufficient oxygen levels.