(ăk″rō-sī-ă-nō′sĭs)
[Pronunciation]
[″ + kyanosis, dark-blue color]

A blue or purple mottled discoloration of the extremities, esp. the fingers, toes, and/or nose.
This physical finding is associated with many diseases and conditions, such as anorexia nervosa, autoimmune diseases, cold agglutinins, or Raynaud's disease or phenomenon. Cyanosis of the extremities may be commonly observed in newborns and in others after exposure to cold temperatures, and in those patients with reduced cardiac output. In patients with suspected hypoxemia, it is an unreliable sign of diminished oxygenation. (Instead of relying on this physical sign, pulse oximetry or arterial blood gases should be measured.)