home
about the project
Medical news
For authors
Licensed books on medicine
<< Previous Next >>

Physiology of the trachea and bronchi

The main function of the trachea and bronchi is respiratory. During breathing, in connection with excursions of the chest, the trachea and bronchi make a number of movements, while the bifurcation of the trachea during inspiration moves down and anterior to 2 cm (Lepnev P.G., 1956). The volume of air in the tracheobronchial tree, the so-called "harmful space" is equal to 120 - 180 ml. Due to the presence, in the annular ligaments and the membranous part of the trachea and bronchi, of smooth muscle fibers, their lumen changes during breathing - expanding when inhaling and narrowing when exhaling. Irritation of the vagus leads to a narrowing of the lumen of the bronchi, and the sympathetic nerve to their expansion. Various harmful impurities contained in the inhaled air in the form of aerosols cause permanent narrowing of the lumen of the respiratory tree in urban residents. Therefore, it is so easy to breathe in the clean air of fields and forests.

Along with the respiratory function of the trachea and bronchi, their drainage, protective and voice functions are distinguished.

The drainage and protective functions of the respiratory tract cannot be strictly distinguished from each other. The first is understood as the mechanisms by which the contents accumulating in them and in the alveoli are removed from the respiratory tract (inflammatory exudate, secret). With the help of protective devices, the body protects itself from those stimuli coming from the external environment that, by their nature, are not characteristic of physiological ones. In this case, the mucous membrane of the respiratory tract performs an important protective function. In contact with the passing air, it warms, moisturizes and dedusts it, protecting the body from the harmful effects of chemical, mechanical and bacterial impurities that enter the inhaled air.

Oscillations of the cilia of the ciliated epithelium, small dust particles and microorganisms move out of the depths of the respiratory tract. The speed of this movement can exceed 2 cm per minute. The secret secreted by the glands and goblet cells envelops extraneous impurities, which gradually accumulate, and then are removed from the respiratory tract by coughing.

The bactericidal properties of mucus, in particular mucin, impede the development of pathogenic flora and neutralize their metabolic products.
The mucous membrane of the trachea and bronchi also has significant suction capacity. This property is used in the clinic for the administration of drugs by inhalation, as well as in the practice of pain relief.

One of the most important protective physiological reflexes is a coughing act. The latter consists of two phases - preparatory and resolving. During the first there is a quick and deep breath with a wide open glottis. During the resolving phase, the vocal folds close tightly, while the tension of the auxiliary muscles in the respiratory tract creates increased pressure. After that, the glottis suddenly opens and the air is expelled with force outward, dragging with itself the contents located in the lumen of the respiratory tract. This important protective physiological reflex of the respiratory tract can have a beginning in the reflex field of the nasal cavity (sensitive endings of the 2nd branch of the trigeminal nerve), described in the late 1920s by K.L. Khilov, as mentioned when considering the physiology of the nose.

The regulation of respiratory function, for the most part, is carried out automatically, through reflex arches and humorally. However, many of them, for example, the frequency and form of breathing, coughing, to a certain extent, and the vocal function, almost entirely, belong to volitional, arbitrary acts.

The functions of the respiratory system are under constant reflex influence of impulses coming from the external environment.

The olfactory, visual, sound, as well as tactile, pain and temperature stimuli coming from the sensitive nerves of the skin and mucous membrane of the respiratory tract can act reflexively on the act of breathing, on the movement of the vocal folds and on the tone of the muscle layer of the trachea and bronchi, regulating their clearance.
<< Previous Next >>
= Skip to textbook content =

Physiology of the trachea and bronchi

  1. Clinical physiology of the larynx, trachea and bronchi
    Resume function. The larynx is part of the airway; when inhaling, it conducts air to the lower sections - the trachea, bronchi and lungs, when exhaling, the air passes in the opposite direction. The act of breathing is provided by the respiratory muscles, and in the larynx by the contraction of the posterior cricoid muscles, which expand the glottis. When breathing, the glottis is always open,
  2. Physiology of the esophagus, trachea and bronchus
    Physiology of the Esophagus, Trachea and
  3. CLINICAL ANATOMY AND PHYSIOLOGY OF THE Larynx, Trachea, and BRONCH
    CLINICAL ANATOMY AND PHYSIOLOGY OF THE LARYNX, TRAJA AND
  4. Malformations of the wall of the trachea and bronchi.
    Malformations of the structural elements of the wall of the trachea, bronchi and bronchioles are morphologically associated with the absence, deficiency or disorganization of cartilage or elastic and muscle tissue. Malformations of the wall of the bronchi can be divided into limited and common. Limited defects of tracheobronchial structures usually lead to local narrowing of a particular segment
  5. Research methods of the trachea and bronchi
    The study of the lower respiratory tract, which include the trachea and bronchi, is carried out by endoscopic and radiological methods. With indirect laryngoscopy, you can see not only the sub-fold space of the larynx, but also the first rings of the trachea. With a deep breath, in individual patients it is possible to examine the trachea throughout the bifurcation area and even the beginning of the main bronchi. However,
  6. Damage to the bronchi and trachea
    Fractures of the first two ribs, sternum and collarbone are the most characteristic bone injuries that cause airway injuries. Hemoptysis, atelectasis, subcutaneous emphysema, pneumomediastinum or pneumothorax, which cannot be corrected by pleural drainage, are signs of possible damage to the main respiratory tract. (The presence of bilateral pneumothorax after blunt injury
  7. Clinical anatomy of the trachea and bronchi
    The respiratory throat (trachea) is a continuation of the larynx, with which it is connected through the cricotracheal ligament (lig. Cricotracheale). Trachea - a long cylindrical tube (length 11-13 cm); it begins at the body level of Suz. and at the level of ThiV — Thv is divided into two main bronchi (bronchus principalis dexter et sinister). The beginning of the septum dividing the trachea is called the spur (carina;
  8. Clinical anatomy of the trachea and bronchi
    The respiratory throat or trachea is a direct continuation of the larynx and refers to the initial section of the lower respiratory tract. The trachea is a hollow elastic tube, somewhat compressed in the anteroposterior direction. Above, through the cricoid-tracheal ligament, it connects to the larynx, below, in the bifurcation area, it is divided into two main bronchi. Distinguish in the trachea
  9. Foreign bodies of the trachea and bronchi
    Most often, foreign bodies of the respiratory tract are found in young children. This is because children, learning the world around them, take various objects into their mouths, and their protective reflexes are not sufficiently developed. The frequency of predominant localization of foreign bodies in the respiratory tract is as follows: in the larynx - 13%, in the trachea - 22%, in the bronchi - 65% (Rokitsky M.R., 1978). Other authors
  10. Clinical anatomy of the esophagus, trachea and bronchus
    Clinical anatomy of the esophagus, trachea and
  11. Injuries, foreign bodies of the esophagus, trachea and bronchus
    Injuries, foreign bodies of the esophagus, trachea and
  12. Inflammation of the bronchi (bronchitis)
    Bronchitis is an inflammatory lesion of the tracheobronchial tree due to irritation of the bronchi by various harmful factors, resulting in a violation of mucus formation and bronchial function, which manifests itself in cough, sputum separation. Bronchitis is considered chronic if the disease lasts for at least three months for more than two consecutive years. At primary
  13. LECTURE No. 19. Respiratory diseases. Acute bronchitis. Clinic, diagnosis, treatment, prevention. Chronical bronchitis. Clinic, diagnosis, treatment, prevention
    LECTURE No. 19. Respiratory diseases. Acute bronchitis. Clinic, diagnosis, treatment, prevention. Chronical bronchitis. Clinic, diagnosis, treatment,
Medical portal "MedguideBook" © 2014-2019
info@medicine-guidebook.com