Hypoxemia is described as which condition?

• A. Low arterial concentration of oxygen
• B. Low oxygen saturation in the blood
• C. Abnormally low concentration of oxygen in the blood
• D. Normal oxygen content

Answer: (C)

Hypoxemia means there is less oxygen in the arterial blood. This is the oxygen available to tissues, reflected by the overall amount of oxygen in the blood, including both the dissolved portion and what’s bound to hemoglobin. The description that states an abnormally low concentration of oxygen in the blood best captures this idea, because it directly conveys that arterial oxygen is reduced. Oxygen saturation describes how much hemoglobin is carrying oxygen and can stay normal in some situations, and normal oxygen content would not indicate hypoxemia. So the best way to describe hypoxemia is that there is an abnormally low concentration of oxygen in the blood.