Proper way to spit out phlegm: Do you really understand the "health signals" behind the color of phlegm?

Coughing up phlegm, a common physiological phenomenon that is often overlooked by us, is an important indicator of the health of the respiratory system.

According to the Lingling District Traditional Chinese Medicine Hospital of Yongzhou City , sputum is the secretion of the trachea and bronchus or the exudate in the alveoli, which contains mucus, bacteria, inflammatory cells and necrotic and detached mucosal epithelial cells. When the respiratory tract is irritated or infected, the amount of sputum secretion will increase. This is a self-protection mechanism of the body, which expel sputum from the body through coughing to keep the respiratory tract unobstructed.

1. Why does coughing up phlegm occur?

This is actually related to the defense mechanism of the respiratory system. Our respiratory tract is in contact with the external environment all the time, and there are various harmful substances such as microorganisms and dust in the air. In order to prevent these harmful substances from entering the lungs, the respiratory tract will secrete mucus to stick to them.

At the same time, the cilia in the respiratory tract will continue to swing, pushing mucus and harmful substances upward, and eventually expelling them from the body through coughing to form sputum. Therefore, coughing up sputum is a self-protection behavior of the respiratory system, which helps to remove foreign matter and pathogens in the respiratory tract .

2. How is sputum produced?

The inner wall of the trachea and bronchi is covered with a layer of mucosa composed of ciliated columnar epithelial cells and goblet cells. The submucosal layer contains a large number of mucous glands and serous glands, and the gland ducts open on the mucosal surface. Under normal circumstances, goblet cells and glands secrete a small amount of mucus that covers the mucosal surface, playing a moist and protective role.

If dust particles, bacteria, and other foreign matter in the trachea and bronchi are inhaled, they are discharged to the upper end of the trachea through mucus adhesion and cilia movement, stimulating the nerve ending receptors and causing a complex and coordinated coughing movement, thereby spitting the mixture out of the mouth. This is sputum.

When the trachea, bronchi and lung tissues are infected by pathogenic bacteria and become inflamed, a large number of inflammatory cells infiltrate, blood vessels dilate, the mucosa becomes congested and edematous, exudation increases, and mucus secretion increases. At the same time, some tissue cells degenerate and necrotize, and then the mucus and necrotic tissue form purulent sputum.

3. Different bacterial infections and different diseases may cause sputum of different colors and properties

1. White: mucous sputum. For example, patients with acute or chronic bronchitis usually have only white mucous sputum or thin colorless mucus in the early stage of coughing up sputum. It may also be light white transparent mucus with thicker viscosity that is not easy to cough up.

2. Yellow: Generally, it is purulent sputum, indicating purulent infection in the respiratory system. It is often caused by bronchitis, bronchopneumonia or mixed lung infection, tuberculosis and other diseases. If the condition worsens, yellow-green sticky lumps or opaque purulent sputum will appear. At this time, it is necessary to suspect lung abscess, chronic bronchitis, bronchiectasis, cavitary tuberculosis combined with severe infection and other diseases.

3. Rust color: It is common in lobar pneumonia caused by Streptococcus pneumoniae and is one of its characteristics. But it can also be seen in pulmonary infarction.

4. Red or brownish red: There is blood or hemoglobin in the sputum, which is seen in lung cancer, tuberculosis, bronchiectasis, etc. Patients with paragonimiasis may have brownish red rotten peach-like sputum, which is caused by the decomposition of necrotic tissue in the lungs; the sputum of acute pulmonary edema is often pink and foamy; patients with Klebsiella pneumoniae pneumonia may have brick-red jelly sputum.

5. Brown: seen in amoebic lung abscess or amoebic liver abscess rupturing into the bronchus.

6. Green: It is more common in patients with lung infections of Pseudomonas aeruginosa and Haemophilus influenzae. Patients with severe jaundice may also have green sputum.

7. Black or gray: commonly seen in various types of pneumoconiosis (such as carbon dust, coal ash, iron dust, stone powder, etc.), and in the sputum of healthy people who smoke too much or live in an environment rich in soot.

8. Milky white sputum: It may be caused by long-term and excessive use of antibiotics, which may suppress bacteria and cause a large number of Candida albicans to multiply, leading to fungal respiratory diseases.

9. Blue: Sputum is rare, and may be caused by inhalation of blue particles or blue substances remaining in the mouth. Transparent or foamy sputum is generally considered sticky sputum, while yellow, green, brown, rust, etc. are all considered purulent sputum.

Coughing up phlegm is not only a symptom of respiratory diseases, but also a way for the body to protect itself. By observing the color, properties and amount of phlegm, potential health problems can be discovered in time. However, coughing up phlegm is not harmless. Sputum contains a large number of bacteria and microorganisms, which may cause gastrointestinal infections if swallowed. Therefore, unless there are special circumstances, it is generally recommended to cough up phlegm.

In some cases, expectoration may become a problem, especially when the sputum is difficult to cough up, and appropriate measures should be taken, such as nebulization therapy, steam inhalation, etc., to help the sputum to be discharged. It is worth noting that if the expectoration persists or is accompanied by other serious symptoms such as difficulty breathing, chest pain, high fever, etc., you should seek medical attention in time to avoid delaying treatment.

In short, coughing up phlegm is an important signal of the health of the respiratory system. By understanding the causes and treatments of coughing up phlegm and strengthening daily care, we can better manage coughing up phlegm and maintain the health of the respiratory system.

Hunan Medical Chat Special Author: Tu Yuehua, Yongzhou Lingling District Traditional Chinese Medicine Hospital

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(Edited by Wx)