Cyanosis is defined as what condition?

Cyanosis is defined as what condition?

• A. Tissue redness due to increased blood flow
• B. Lack of blood flow to a limb
• C. Excess oxygen in tissues
• D. Lack of oxygen; tissues turn blue

Answer: (D)

Cyanosis is the bluish discoloration of the skin and mucous membranes caused by insufficient oxygen in the blood. When tissues extract more oxygen, hemoglobin becomes deoxygenated and darker; deoxygenated hemoglobin absorbs more red light and reflects blue, giving the blue tint. This differs from redness due to increased blood flow, from ischemia where blood supply is blocked, or from too much oxygen in tissues. Clinically, cyanosis can indicate low arterial oxygen (central cyanosis) or localized poor perfusion (peripheral cyanosis).

Cyanosis is the bluish discoloration of the skin and mucous membranes caused by insufficient oxygen in the blood. When tissues extract more oxygen, hemoglobin becomes deoxygenated and darker; deoxygenated hemoglobin absorbs more red light and reflects blue, giving the blue tint. This differs from redness due to increased blood flow, from ischemia where blood supply is blocked, or from too much oxygen in tissues. Clinically, cyanosis can indicate low arterial oxygen (central cyanosis) or localized poor perfusion (peripheral cyanosis).