Cyanosis is a condition characterized by a bluish discoloration of the skin, nails or mouth, and is usually a symptom of diseases that can interfere with oxygenation and blood circulation, such as congestive heart failure (CHF) or chronic obstructive pulmonary disease (COPD).
According to the cause, cyanosis can be classified into:
- Peripheral, which happens when the circulation speed is slowed down, with not enough oxygenated blood circulation for the whole body; Central, in which blood arrives in the arteries without oxygen, being the main cause of lung diseases; Mixed, which occurs when not only the oxygenation process that occurs in the lungs is impaired but also the heart is unable to promote sufficient transport of oxygenated blood.
Venous blood, rich in carbon dioxide and low in oxygen, is transported through the veins to the lungs, where they lose carbon dioxide and gain oxygen, which is transported due to hemoglobin, which is one of the components of red blood cells. The oxygenated blood, called arterial, is transported through the arteries to the heart and, consequently, to the entire body.
Main causes
Cyanosis can be caused by any condition that interferes with the process of oxygenation and blood transport and can happen both in adulthood and in newborns. The main causes of cyanosis are:
- Lung diseases, such as COPD, pulmonary embolism or severe pneumonia, for example; Heart disease, with CHF or thrombosis; Intoxication by drugs, such as Sulfa, for example; Tetralogy of Fallot or Blue Baby Syndrome, which is a genetic disease characterized by changes in the heart that decrease its efficiency. See what Fallot's Tetralogy is and how it is treated; Changes in hemoglobin, which can be identified through the heel prick test right after birth - Learn more about the heel prick test.
In addition, cyanosis is common when there is prolonged exposure to cold, highly polluted environment or at high altitudes, as they decrease the efficiency of blood circulation.
The diagnosis is made through physical examination, evaluation of the person's clinical history and laboratory tests that assess the concentration of hemoglobin in the blood and the efficiency of gas exchange, which is verified by means of the arterial blood gas analysis. Understand what it is and how to understand the blood gas analysis.
How the treatment is done
The treatment of cyanosis is done according to the cause, the use of oxygen masks, practice of physical exercises to improve blood circulation and the oxygenation process, or wear warmer clothes, when cyanosis is caused by cold, may be indicated., for example.
