Which statement lists factors that influence hypoxic hypoxia?

Which statement lists factors that influence hypoxic hypoxia?

• A. Altitude
• B. Altitude, time spent at altitude, rate of pressure change, physical activity during flight
• C. Rate of pressure change
• D. Time spent at altitude

Answer: (B)

Hypoxic hypoxia happens when there isn’t enough oxygen entering the blood because ambient oxygen pressure is low at altitude. How severe it becomes depends on several interacting factors. The higher you fly, the lower the inspired oxygen is, so arterial oxygen content drops. If you remain at that altitude longer, you’re exposed to the low oxygen for more time, which can worsen symptoms and increase the risk of hypoxia. The rate at which pressure changes during ascent or descent matters because a rapid drop in pressure means the lungs and blood have less time to compensate, so oxygen delivery to tissues can fall quickly. Finally, physical activity raises the body's oxygen demand; during flight, exercising increases how much oxygen tissues need, making the effect of reduced inspired oxygen more pronounced. All these factors together explain why altitude, time at altitude, rate of pressure change, and physical activity during flight collectively influence hypoxic hypoxia.

Hypoxic hypoxia happens when there isn’t enough oxygen entering the blood because ambient oxygen pressure is low at altitude. How severe it becomes depends on several interacting factors. The higher you fly, the lower the inspired oxygen is, so arterial oxygen content drops. If you remain at that altitude longer, you’re exposed to the low oxygen for more time, which can worsen symptoms and increase the risk of hypoxia. The rate at which pressure changes during ascent or descent matters because a rapid drop in pressure means the lungs and blood have less time to compensate, so oxygen delivery to tissues can fall quickly. Finally, physical activity raises the body's oxygen demand; during flight, exercising increases how much oxygen tissues need, making the effect of reduced inspired oxygen more pronounced.

All these factors together explain why altitude, time at altitude, rate of pressure change, and physical activity during flight collectively influence hypoxic hypoxia.