What is hypoxia in the context of flying?

Hypoxia refers specifically to a deficiency of oxygen reaching the tissues. This condition can occur at high altitudes where the atmospheric pressure is lower, leading to a reduced availability of oxygen. In the context of flying, especially during high-altitude flights, pilots and passengers may experience hypoxia if the cabin is not properly pressurized or if they are exposed to oxygen levels that are too low for optimal bodily function. The body's tissues require a constant and adequate supply of oxygen to operate effectively; a deficiency can result in various symptoms, such as fatigue, impaired judgment, and in severe cases, loss of consciousness. Understanding this is crucial for pilots to ensure safety during flight operations, especially at elevation.