Peripheral cyanosis is the bluish discoloration of the skin and mucous membranes due to low oxygen levels in the blood, states Healthline. The condition may also occur as a result of a high level of abnormal protein in red blood cells. Bluish fingertips and lips may signal that a person has an underlying medical condition.
Blood that contains enough oxygen is typically bright red, while blood with low levels of oxygen forms a purple or bluish cast, according to Healthline. Cold temperatures, peripheral heart disease, congestive heart failure and shock may cause vasoconstriction of blood vessels, forming blue tints on extremities.
Causes of peripheral cyanosis include Raynaud’s phenomenon, accumulation of fluid in the heart, arteriosclerosis and deep vein thrombosis, notes Healthline. Carbon monoxide poisoning, aspiration pneumonia and pulmonary embolism may cause the problem as well. A medical and physical examination may help diagnose the condition. The doctor may further perform X-rays and blood tests to determine the exact cause of the problem.
A person who has a blue cast on his extremities and experiences chest pain, breathing difficulties, extreme sweating, fainting or dizziness should seek immediate medical attention, cautions Healthline. Pain, numbness and blanching of fingers, arms or hands require immediate medical care as well. Treating underlying conditions and improving circulation of oxygen to the affected area may cure the condition.