Why has the color of my face turned dark


Brief overview

  • What is cyanosis? Bluish discoloration of the skin and mucous membranes due to insufficient oxygen levels in the blood. Typical are e.g. blue lips, earlobes, fingertips.
  • to shape: peripheral cyanosis (as a result of increased oxygen depletion in the body periphery such as arms and legs), central cyanosis (as a result of insufficient oxygen loading of the blood in the lungs).
  • causes: For peripheral cyanosis, cold, circulatory disorders, blood changes, cold agglutinins (autoantibodies in the blood), varicose veins. With central cyanosis, lung diseases (e.g. asthma, COPD), heart diseases (e.g. heart failure, heart valve defects), poisoning (e.g. with carbon dioxide, medication).
  • diagnosis: Initial consultation, physical examination, blood tests, measurement of pulse and oxygen saturation in the blood using pulse oximetry, further tests depending on the suspected cause of the cyanosis (e.g. EKG, heart ultrasound, lung function test).
  • treatment: Therapy of the underlying disease.
  • Danger: In the event of acute cyanosis with shortness of breath / shortness of breath, call the emergency number immediately (Tel. 112) and provide first aid!

Cyanosis: definition

Doctors speak of cyanosis when the skin or mucous membranes (lips) are discolored bluish because the blood does not contain enough oxygen:

The oxygen absorbed in the lungs is bound to the red blood cells (erythrocytes) - more precisely: to their pigment hemoglobin - transported to all regions of the body. The body cells absorb oxygen from the blood and release carbon dioxide (a waste product of various metabolic processes) into the blood. The now oxygen-poor, but carbon dioxide-rich blood flows back into the lungs, where the gas exchange takes place again - release of carbon dioxide and absorption of oxygen.

If the hemoglobin contains a lot of oxygen, the blood is bright red. When there is little oxygen, it becomes darker and looks bluish. This becomes visible on thin areas of the skin, where the blood vessels running directly under the skin are most likely to shine through. That explains about the blue lips, earlobes and fingertips in cyanosis.

The bluish discoloration of the skin and mucous membrane is the reason why cyanosis was previously called "blue rash".

Cyanosis: forms

Doctors differentiate between peripheral and central cyanosis, which can also occur in combination, depending on the origin:

  • central cyanosis: The lack of oxygen is of central origin - the blood flowing from the lungs to the periphery of the body is not adequately oxygenated. Possible causes for this are, for example, lung diseases (pulmonary cyanosis) or heart defects (cardiac cyanosis).
  • peripheral cyanosis: Based on an increased oxygen depletion of the blood in the body periphery. This can happen, for example, when the blood flow is slowed down due to the cold, which is reflected in blue lips and blue fingernails.

If only the so-called body acras (nose, fingers, toes) are cyanotic, one speaks of acrocyanosis.

Cyanosis: causes and development

The possible causes of cyanosis depend on whether the patient is peripheral or central.

Peripheral cyanosis: causes

Peripheral cyanosis is based on increased oxygen depletion of the blood in the periphery of the body - either due to slowed blood circulation or decreased blood flow. Possible causes for peripheral cyanosis are, among others:


To reduce heat loss, the blood vessels contract when it is cold. The blood flow to the periphery of the body slows down and decreases, which increases oxygen utilization. The first sign of this is usually blue lips, as the skin on the lips is particularly thin and translucent.


Blood clots can cause thrombosis (venous thrombosis), mainly in the leg veins. Oxygen-poor blood can then no longer flow out via the narrowed veins. A swollen, sore leg with stretched skin and possibly a bluish discoloration are signs of a leg vein thrombosis.

If you suspect a thrombosis, you should consult a doctor immediately! A detached blood clot (thrombus) can clog a lung vessel (pulmonary embolism), which can be life-threatening!

Blood changes

Changes in blood composition can also cause peripheral cyanosis. An example of this is an increased concentration of functionless methemoglobin in the blood (Methemoglobinemia). This substance arises from the conversion of hemoglobin. If the metahemoglobin is too large, there is too little hemoglobin available for oxygen transport.

Another example of a blood change that can cause peripheral cyanosis is a Excess red blood cells (Polyglobules). It can slow down the flow of blood.

Last but not least, you can too Cold agglutinins decrease blood flow. These are autoantibodies in the blood that can become effective at temperatures of 10 to 15 ° C (autoantibodies are antibodies that are directed against the body's own substances). The cold agglutinins cause the red blood cells to clump together (agglutination) and then dissolve.

Varicose veins (varicosis)

Varicose veins are a sign of weak veins. The blood sinks into the deep or superficial leg veins and causes cyanosis.

Heart disease

In people with cardiac insufficiency, the heart muscle can only pump the blood through the circulation with reduced force. The slowed down circulation can lead to increased oxygen depletion in the body periphery and thus generalized to a bluish discoloration of thin skin and mucous membrane areas on the body.

Heart failure can develop, for example, as a result of narrowing heart valves (heart valve stenosis) or cardiac arrhythmias.

Central cyanosis: causes

Central cyanosis is caused by insufficient oxygen loading of the blood. Reasons for this are:

Lung disease

A central cyanosis that develops due to lung disease will pulmonary cyanosis called. Its most common causes include:

  • asthma
  • Bronchiectasis: These are irreversible enlargements of the bronchi. They can be congenital (e.g. in cystic fibrosis) or develop in the course of life (e.g. due to tumors or scarring as a result of pneumonia).
  • Chronic Obstructive Pulmonary Disease (COPD): This chronic progressive lung disease causes coughing, shortness of breath, and sputum.
  • Pneumothorax (lung collapse): It occurs when air enters the pleural space (gap-shaped space between the lungs and chest wall), e.g. as a result of chest injuries. Typical symptoms are shortness of breath, cyanosis, and shortness of breath.
  • Inflammation of the lungs (pneumonia)
  • Pulmonary emphysema: Pulmonary flatulence, i.e. over-inflated and partly destroyed alveoli. Possible causes are e.g. smoking, COPD, chronic bronchitis.

Heart defect

A cardiac cyanosis occurs when, due to a heart defect, oxygen-poor blood is added to the oxygen-rich blood that comes out of the lungs before it continues to flow to the periphery of the body. Heart defects that can be the cause of this include Fallot's trilogy, Fallot's tetralogy and ventricular septal defect with shunt reversal.


Poisoning with substances that inhibit gas exchange in the body can manifest itself as cyanosis. These include, for example, poisoning with:

  • Carbon dioxide
  • Medicines (e.g. agents against cardiac arrhythmias = antiarrhythmics, salicylic acid)
  • Pesticides
  • Opiates (psychoactive substances from the milk sap of the opium poppy)

Diseases with this symptom

Find out here about the diseases that can cause the symptom:

Cyanosis: diagnosis

If the cyanosis is persistent and not caused by the cold, you should see a doctor to clarify the cause. This is especially true if you also suffer from acute shortness of breath, coughing and breathing difficulties and / or physical weakness and rapid fatigue.

In a face-to-face meeting, the doctor will contact you Medical history raise (anamnesis). For example, he asks:

  • Since when has the cyanosis (e.g. bluish lips) been evident?
  • In addition to cyanosis, do you have other symptoms such as shortness of breath or cough?
  • Do you have heart or lung disease?
  • Are you taking any medication? If yes, which?

Then a so-called follows Eye diagnosis: The doctor checks whether the lips, earlobes, mucous membranes, tip of the nose or fingernails are clearly discolored blue.

A simple test helps to differentiate between central and peripheral cyanosis (but it is not 100 percent reliable): The doctor looks at the color of the tongue. If it is pink in color while the lips are bluish, peripheral cyanosis is likely. A bluish discoloration of both the lips and tongue, on the other hand, indicates central cyanosis.

Are instructive in the clarification of cyanosis Blood tests: A blood count is created with an analysis of the blood gases. Important values ​​are, for example, the number of red blood cells (erythrocytes), the hemoglobin content in the red blood cells and the oxygen content of the blood.

Oxygen saturation can be achieved quickly and painlessly by means of Pulse oximetry determine. Here, a finger of the person affected is illuminated by a small clip with infrared light. The oxygen content is determined based on the color of the blood - oxygen-rich blood is light red, oxygen-poor blood is bluish. The oxygen content should be 98 to 100 percent.

Further investigations depend on what the doctor suspects is the cause of the cyanosis. If there is a suspicion of a heart disease, the following examinations, among others, can bring clarity:

  • Chest x-ray (chest x-ray)
  • Electrocardiography (EKG)
  • Echocardiography (heart ultrasound)
  • Cardiac catheterization
  • Computed tomography (CT)
  • Magnetic resonance imaging (MRI)

The doctor uses a lung function test to track down any lung diseases. This can be used to detect asthma, bronchitis, COPD and other lung diseases.


If there is an underlying disease such as varicose veins, heart failure or COPD behind the cyanosis, this must be treated appropriately. For example, patients with heart failure receive medication that relieves the weakened heart muscle.

First aid is required in acute cyanosis! Because it can be life-threatening.

Acute cyanosis: first aid

In acute cyanosis, accompanying symptoms such as shortness of breath or attacks of suffocation often occur. Then there is Danger to life from acute lack of oxygen. Because if the body is not supplied with oxygen for a longer period of time, life-threatening failures occur: the person affected becomes unconscious after just a few seconds. After three minutes, brain cells die. Therefore, those affected need to be supplied with oxygen as quickly as possible.

As a first aider, you should consider the following tips:

  • Call the emergency: Dial 112 immediately!
  • Mouth check: Check whether the patient has swallowed something or whether there is still something in the mouth that he could swallow if he inhaled deeply, for example dentures. Remove the object in question.
  • Make breathing easier: Calm the patient down and bring him into a position where he can breathe more easily. In the "coachman position" the upper body is bent forward while the arms are supported on the thighs. The person concerned should now try to breathe purposefully and consciously. Open clothing items to avoid further tightness.
  • use asthma spray if necessary: Ask them if they are asthmatic and have an asthma spray with them. Because it could also be an asthma attack. If necessary, help the person affected with the application of the spray.
  • Hyperventilation: Violent excitement can lead to the person breathing much too quickly. This hyperventilation can often be recognized by the "paws" position of the hands. Then hold a small plastic or paper bag in front of the patient's mouth, into which he inhales and exhales - this will regulate breathing and blood gas values ​​again.
  • Foreign body swallowed? Strong blows between the shoulder blades can help loosen a wedged foreign body. If that doesn't help, try the "Heimlich grip": Embrace the person affected from behind and place a fist on the upper abdomen below the breastbone. Now pull your fist sharply in your direction with the other hand. Repeat the maneuver until the foreign body is spat out.

Be aware of one thing: laypersons can only help people with shortness of breath to a limited extent! So call at cyanosis an emergency doctor immediately who can treat the person affected professionally.

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