Hypoxia is defined as what condition in the body?

• A. A state of oxygen surplus in the body.
• B. A state of oxygen deficiency in the body sufficient to impair brain and other organs.
• C. A condition caused solely by high altitude.
• D. Excess oxygen in the bloodstream.

Answer: (B)

Hypoxia means the body's tissues aren’t getting enough oxygen to meet their needs, so brain and other organs start to function impairedly as oxygen delivery falls. This is why the description focusing on oxygen deficiency sufficient to impair brain and other organs is the correct one. An oxygen surplus isn’t hypoxia, and excess oxygen in the bloodstream is hyperoxia, not hypoxia. While high altitude is a common situation that can lead to hypoxia, it isn’t the sole cause, since any situation that reduces oxygen delivery can produce hypoxia. In aviation, recognizing hypoxia early and using supplemental oxygen when needed helps prevent cognitive and physical performance decline.