Bluish discolored lips or fingertips indicate cyanosis. A lack of oxygen in the blood causes the skin and mucous membranes to turn blue. What causes cyanosis and when is medical attention needed?
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What is cyanosis?
A bluish discoloration of the skin caused by a lack of oxygen in the blood is called cyanosis in medicine. A meanwhile rather outdated term is blue addiction. Gas exchange takes place in the lungs: the carbon dioxide from the tissue is absorbed from the blood by the alveoli and, in return, oxygen is released into the blood. There it binds to the blood pigment hemoglobinwhich transports oxygen to the peripheral tissues.
Oxygen-poor blood is bluish in color instead of red and therefore appears dark through the skin. The nose, chin, fingernails and toes are often affected – since they are called acren in medical terms, their blue discoloration is referred to as acrocyanosis.
Depending on the cause, there are two forms of cyanosis:
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Peripheral cyanosis: The cause here is increased oxygen depletion in the blood, usually caused by heart failure. the arterial oxygen saturation is normal. Blue lips, fingers, and toes commonly occur.
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Central cyanosis: It is characterized by reduced arterial oxygen saturation. A common cause is a malformation of vessels or insufficient enrichment of the blood with oxygen in the lungs. Typical of central cyanosis is the additional occurrence of a blue tongue and deep red to bluish colored mucous membrane in the mouth.
An acute lack of oxygen associated with shortness of breath is an emergency and requires immediate medical attention.
Symptoms: How to recognize cyanosis
Clear signs of low oxygen levels in the blood are bluish lips, fingernails, earlobes and oral mucosa. Other symptoms that often accompany cyanosis are shortness of breath, headache, fatigue and loss of performance. Depending on the form and the underlying cause, the skin can be cool or warm, with a Thrombosis and other outflow disorders in the vein, swelling usually occurs.
Chronic central cyanosis often leads to changes in the fingers, toes, and nails. Drumstick fingers (enlarged and thickened end phalanges) and watch glass nails (nails bent outwards) form.
Causes of visible reduced blood flow
The triggers for a reduced oxygen content in the blood and the resulting blue discoloration of the skin are different. Often, cyanosis is just the body’s reaction to cold—the blood vessels constrict and blood flow slows. This reduces heat loss.
However, since severe heart disease and lung disease can also be the cause of the lack of oxygen, patients should take the symptom seriously and have it checked by a doctor if they suspect it. This is especially true if other symptoms such as breathing problems occur.
Disorders that cause cyanosis:
Poisoning, for example with carbon dioxide, alkaloids or plant protection products (pesticides) can dangerously lower the oxygen content in the blood. In rare cases, drugs such as antiarrhythmic drugs used to treat cardiac arrhythmias insufficiently oxygenated blood.
Medical diagnosis when cyanosis is suspected
If cyanosis is suspected, the doctor determines the amount of oxygen in the blood. For this purpose, a sensor is attached to the fingertip (pulse oximetry) or a blood gas analysis is carried out. Cyanosis is present when the oxygen content is below 4-5 grams of hemoglobin per 100 milliliters of blood.
To clarify the underlying cause of the insufficient oxygen saturation in the blood, a Röntgen-Thoraxone Echocardiographycardiac catheterization or pulmonary function test be made. With the hyperoxia test, doctors can determine whether the central cyanosis is caused by the heart (cardiac) or the lungs (pulmonary): Cyanotic patients breathe in pure oxygen for several minutes. The signs of cyanosis disappear in the pulmonary form, but not in the cardiac form.
Which treatment is suitable?
If the oxygen concentration in the blood is too low, oxygen therapy is given immediately in emergencies. In this way, the level in the blood is increased again and life-threatening accompanying symptoms such as shortness of breath or impending suffocation are eliminated.
If an underlying disease is causing the cyanosis, it is treated accordingly. For example, a malformation of blood vessels can be surgically corrected with an operation, lung diseases such as pneumonia and heart diseases can be treated with medication.
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summary
Symptoms: Blue discoloration of the skin and mucous membranes, breathing problems, decreased performance and fatigue
Treatment: In acute cases, give pure oxygen, treat underlying diseases with medication or surgery
Causes: Exposure to cold, often lung diseases such as pneumonia or heart diseases such as cardiac insufficiency