Trachea and bronchi: functions and diseases

To supply the body with nutrients, we need food. Also, we can not do without water, since more than half of this vital liquid. But to everything else the human body needs oxygen, which our respiratory system takes from the air. In this, the trachea and bronchi actively help.

If access to air is difficult, then to get the necessary amount of oxygen for breathing, the respiratory system with the heart begin to work hard. But what is even more interesting, the human respiratory system can adapt to environmental conditions.

Importance of the respiratory system

The role of the respiratory system is difficult to overestimate. As we can already know from the lessons of biology, when exhaling, we get rid of CO ₂ carbon dioxide. When breathing into the lungs, oxygen enters, which from them circulates through the circulatory system to all tissues of the internal organs. Thus, gas exchange is carried out. Being at rest, we consume 0.3 liters of oxygen every minute, while in the body some CO _{2 is formed} and it is less.

In medicine, there is a term called the respiratory quotient, which reflects the ratio of the amount of carbon dioxide inside our body to the amount of oxygen supplied to the trachea and bronchi. Under normal conditions, this ratio is 0.9. It is maintaining such an equilibrium and is the main task that the human respiratory system fulfills.

Structure of the respiratory system

The respiratory system is a whole complex, which consists of the following components:

• Nasal cavity;
• Paranasal sinuses;
• Larynx;
• Trachea;
• Bronchi;
• Lungs.

To better understand how this or that disease, inherent in the respiratory system develops, it is worth analyzing how its individual components are arranged.

We also learn what role they play in our body. Only in more detail we will consider the analysis of bronchi and trachea, as they are more likely to undergo pathological changes.

Trachea

Trachea is an intermediate link between the larynx and bronchi. Both trachea and bronchi have a common structure and look like tubes. Only the length of the first is of the order of 12-15 cm and a diameter of about 1.5-1.8 cm, although with age, it may vary slightly. Unlike the lungs, it is an unpaired organ. This is a fairly flexible body, as represented by a compound of 8-20 cartilaginous rings.

It is located between the sixth cervical and fifth thoracic vertebrae. In the lower part of the trachea branched into two main canals, but before the separation it slightly narrows. Such a split in the medical language has its name - bifurcation. This region has a variety of sensitive receptors. It should be noted that the trachea has a slightly flattened shape, if you orientate from the front to the back. For this reason, its transverse section is about a couple of millimeters larger than the sagittal parameter.

Continuing the examination of the trachea (and bronchi will also be described), it should be noted that the thyroid gland adjoins the upper part of the tracheal tube, and behind it is the esophagus. The body lining the mucosa, which is characterized by its ability to suck. For this reason, it is good to administer inhalation. It is also lined with muscular-cartilaginous tissue, which has a fibrous structure.

Bronchial tree

From the visual point of view, the bronchi resemble a tree, only as if turned upside down. Like the lungs, it is also a paired organ, which is formed by dividing the trachea into two tubes, which are the main bronchi.

Each such tube, in turn, is divided into smaller branches that go to different sections and portions of the lungs. The right organ is slightly different from the left one: it is slightly thicker, but shorter and has a more pronounced vertical arrangement. Many diseases of the trachea and bronchi are associated with inflammation of the respiratory tract.

The whole structure has a characteristic name - a bronchial tree, whose structure, in addition to the main bronchi, includes many branches:

• Share;
• Segmented;
• Subsegmental;
• Bronchioles (lobular, terminal and respiratory).

The trunk of this inverted tree is the trachea itself, from which the two main bronchi (right and left) depart. From them there are share tubes of slightly smaller size, and in their right lung there are three, and in the left - only two. These tubes are also divided into smaller segmental bronchi and, eventually, all ends with bronchioles. Their diameter is less than 1 mm. At the ends of the latter are small so-called bubbles called alveoli, where, in fact, carbon dioxide is exchanged for oxygen.

Interestingly, the trachea, bronchi, lungs differ in their peculiar structure (although the first two organs are similar). The walls of the bronchi have a cartilaginous annular structure, which prevents their spontaneous narrowing.

Inside the bronchi are lined with a mucous membrane with ciliate epithelium. The entire tree structure receives nutrition through the bronchial arteries emanating from the thoracic aorta, and it is penetrated by the lymph nodes and nerve branches.

Functional function of the respiratory trachea and bronchi

The function of the trachea and bronchi is not only to ensure the correct gas exchange in the lungs, but is multifaceted. For example, a flexible tube in our body works as a resonator, since air passes through the vocal cords. Thus, the trachea takes part in the formation of the voice. As for the bronchi themselves, they are capable of destroying and neutralizing some toxic substances that are harmful to our body.

In addition, the mucous larynx, trachea, bronchus are covered with a ciliated epithelium, which contains cilia. Their movement is directed to the larynx and mouth. Present in the mucous membrane of the gland secrete a special secret that, when a foreign body enters, immediately envelops it and, thanks to the movement of the cilium, facilitates the release into the oral cavity. The ingress of a large foreign body reflexively causes a cough.

But, which is especially interesting, the air, passing through the trachea and bronchi, heats up to the necessary temperature and becomes wet. Lymphonoduses in the bronchi take part in important immune processes in the body.

Pathological changes in the respiratory system

Often the diseases of the trachea or bronchus occur in the form of inflammatory processes of their mucous membrane. They can occur in both acute and chronic forms. As for the nature of the inflammation, it can be:

• Catarrhal;
• Fibrinous;
• Purulent;
• Putrid.

Violation of the function of the trachea and bronchi means damage to the bronchi or trachea. In this case, if we consider the first, then the change in large bronchi is called macrobonchitis, and bronchioles - microbrochitis, or bronchiolitis. Among the most common pathologies include bronchial asthma and tracheitis - inflammation of the trachea.

Diseases of the trachea

Among the diseases of the trachea is stenosis, fistula and thermal burn. In most cases, tracheitis, which is widespread, can go to another pathology - bronchitis, and in this case it is known as tracheobronchitis. Pathology seems harmless, but later there can be serious complications. Therefore, it is better not to delay the treatment of this disease.

Tracheitis in rare cases occurs as an independent disease (primary manifestation), most often this is the consequence of some untreated pathology of the respiratory system (secondary manifestation). Anyone can arise, regardless of age and sex. Most often, lungs, bronchi, trachea, and children's larynx are under threat because their immune system is still too weak to properly deal with certain threats.

There are several types:

• acute;
• chronic;
• infectious;
• Non-infectious;
• mixed.

In this case, the disease of an infectious nature can be viral, fungal or bacterial.

Diseases of the bronchi

A common case of bronchial involvement is bronchitis, which is also worth mentioning. Pathology is expressed by inflammation of the walls of the respiratory tubes. Causes of the disease can serve as various factors, which may include:

• The presence of bacteria or viruses.
• Long period of consumption of tobacco products.
• Predisposition to allergens.
• Exposure to chemical or toxic substances.

Thus, the disease can be of the following type:

• Bacterial;
• Virus;
• Chemical;
• Fungal;
• Allergic.

Therefore, it is extremely important that the doctor on the basis of the results of the conducted studies accurately determine the type of disease of the bronchi, trachea. Like any disease, bronchitis manifests itself in acute and chronic forms.

The acute form proceeds with an increased temperature, accompanied by a dry or wet cough. Basically, with proper treatment passes in a few days. In some cases, it takes several months. Often acute bronchitis is classified as a cold or an infectious disease. As a rule, does not end with any consequences.

Chronic bronchitis can last for several years. In this case, the patient has a cough, and every year there are exacerbations that last for more than one month.

The main thing is to give due attention to the acute stage of the disease so that it does not go into chronic form. Long-term effects of the disease on the body does not pass without a trace and can lead to complex, irreversible consequences for all respiratory organs.

Treatment

Depending on the diagnosis (bronchitis, tracheitis), the nature of the course of the disease, the presence of risks of exacerbation, the necessary course of treatment is prescribed. Considering the possibility, whether the inflammation of the trachea, bronchi can cause serious exacerbations or not, the attending physician decides to send the patient to the hospital, or he can undergo treatment at home.

Therapy includes a wide range of measures, which, in addition to medical preparations, includes a number of physiotherapeutic procedures: from warming up and inhalation to massage and physical education.