>>1697010>use the same air pressure as external atmoshere>Hypoxic hypoxia is a result of insufficient oxygen available to the body as a whole. A blocked airway and drowning are obvious examples of how the lungs can be deprived ofoxygen, but the reduction in partial pressure of oxygen at high altitude is an appropriate example for pilots. Although the
percentage of oxygen in the atmosphere is constant, its partial
pressure decreases proportionately as atmospheric pressure
decreases. As an aircraft ascends during flight, the percentage
of each gas in the atmosphere remains the same, but there are
fewer molecules available at the pressure required for them
to pass between the membranes in the respiratory system.
This decrease in number of oxygen molecules at sufficient
pressure can lead to hypoxic hypoxia.