Diffusion hypoxia is a type of ……………hypoxia
**Core Concept**
Diffusion hypoxia is a rare but potentially life-threatening condition that occurs when a diver surfaces too quickly after breathing a gas mixture containing high concentrations of inert gases, such as nitrogen. This phenomenon is related to the rapid exchange of gases between the lungs and the bloodstream, leading to a temporary mismatch between oxygen delivery and demand.
**Why the Correct Answer is Right**
Diffusion hypoxia is a type of hypoxia that occurs when the rapid diffusion of inert gases from the alveoli into the bloodstream causes a decrease in oxygen availability. This is due to the displacement of oxygen by the inert gases, which dilutes the oxygen concentration in the arterial blood. As a result, the brain and other tissues may experience a temporary decrease in oxygen supply, leading to symptoms such as dizziness, confusion, and even loss of consciousness.
**Why Each Wrong Option is Incorrect**
**Option A:** High-altitude hypoxia is incorrect because diffusion hypoxia is not related to the low oxygen levels found at high altitudes.
**Option B:** Anemic hypoxia is incorrect because diffusion hypoxia is not caused by a lack of red blood cells or hemoglobin.
**Option C:** Carbon monoxide poisoning is incorrect because diffusion hypoxia is not caused by the inhalation of carbon monoxide.
**Clinical Pearl / High-Yield Fact**
To avoid diffusion hypoxia, divers should follow a gradual ascent profile, allowing time for the inert gases to be slowly exhaled from the body. This is known as a "safe stop" at a depth where the pressure is equal to the pressure at the surface.
**Correct Answer:** D. Diffusion hypoxia