Cyanosis

Cyanosis is a medical problem where the skin changes color. When a person has cyanosis their skin and mucous membranes turn blue or purple.

Causes
Cyanosis is a sign that the cyanotic (blue) parts of the body are not getting enough oxygen in blood there. This can happen because there is not enough oxygen in the blood. It can also happen when small blood vessels in the body get smaller because of a medical problem, which is called vasoconstriction.

Manifestations
Cyanosis tends to be seen in the extremities the parts of the body that are farthest away from the heart. Usually, the first parts of the body to become cyanotic are the fingertips (especially under the fingernails), the toes, the lips, the tip of the nose, and the earlobes.Lippincott Manual of Nursing Practice Series: Assessment. Lippincott Williams & Wilkins; 1 edition (2006) p.87  As the body goes longer without oxygen, more parts of the body become cyanotic.

Related pages
 Circulatory system
 Acrocyanosis
 Blue baby syndrome
 Raynaud's phenomenon
 Blue Fugates

References

 Other websites 

Category:Medical signs
Category:Blood disorders