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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.

In the trachea, cartilaginous and membranous parts are distinguished. The basis of the first is hyaline cartilage (an average of 16 - 20), having a horseshoe-shaped shape, the ends of which are turned posteriorly. Tracheal rings are interconnected by strong annular ligaments, which are almost twice as wide as cartilaginous rings.

Continuing posteriorly, the annular ligaments pass into the continuous posterior membranous part of the trachea, accounting for 1/4 - 1/5 of its entire circumference. The membranous part of the trachea is formed by collagen and elastic fibers. Smooth muscle fibers are located in the annular ligaments, and especially in the posterior membranous part of the tracheal wall. Thanks to the connective tissue and muscle fibers, the trachea has significant stretch and elasticity.

Outside, the trachea has a connective tissue membrane (adventitia), which is surrounded by loose paratracheal tissue. The inner surface of the trachea is lined with a mucous membrane, which is very similar to the mucous membrane of the larynx. It is covered with a multi-row cylindrical ciliated epithelium, the villi of which make rhythmic oscillatory movements in the direction of the larynx. The submucosal layer contains a large number of mixed glands that produce a protein-mucous secretion.

The trachea occupies a strictly midline position on the neck and chest (Fig. 5.3). Its total length in an adult is 11-13 cm, width from 15 to 13 mm. In adults, its upper edge is at the level of VI - VII cervical vertebrae, the lower at the level of IV - V thoracic vertebrae. In the trachea, the cervical and thoracic sections are distinguished, which is demarcated by a line running at the level of the upper opening of the chest.

The cervical trachea along with the larynx is very mobile, as it is surrounded throughout the loose fiber. When swallowing, phonation and throwing the head back, the trachea together with the larynx can significantly shift upward, as if stretching out of the chest cavity. She also easily shifts to the sides when turning the head.

The trachea has two permanent constrictions. The first narrowing is located in the initial part, directly under the larynx, the second is 3 cm above the bifurcation. As far down, the trachea is further and further removed from the surface of the body. While the distance of the first tracheal ring from the skin in adults is 1 - 1.5 cm, in the area of ​​the jugular notch this distance reaches 4 cm. Depending on the constitution, significant individual variants of the position and topography of the trachea are noted, which is of great clinical importance.

On the neck in front of the trachea, the sternum-hyoid and sternum-thyroid muscles, as well as the thyroid gland, the variants of which and, especially, the isthmus, also have great variability and are of significant clinical interest.

In children under the age of 14–16 years, the thymus gland is located in the upper thoracic region approximately at the level of the sternum handle in front of the trachea.

On the neck, the trachea lies directly in front of the esophagus.
In the gutters formed by the walls of the esophagus and trachea (tracheo-esophageal grooves), branches of the vagus nerves are located on both sides. To the right and left of the trachea are the vital neurovascular bundles containing the common carotid artery, internal jugular vein and vagus nerve. In the chest cavity, the pleural bags of the right and left lung are adjacent to the trachea and it is the boundary between the posterior and anterior mediastinum.

At the level of IV-V thoracic vertebrae, the trachea is divided into the right and left main bronchi. The division of the trachea into the bronchi is called bifurcation. At the site of bifurcation of the trachea, a small protrusion is formed - a spur or keel (carina), deviated somewhat to the left.

The right main bronchus is wider and shorter than the left and is a continuation of the trachea. Due to this, as well as the deviation of carina, foreign bodies more often (but not always) fall into the right bronchus. The length of the right bronchus is 3 cm, the left is about 5 cm. The discharge angle of the right bronchus, on average, ranges from 25 to 35 ?, and the left from 45 to 75? (G.I. Lukomsky). Thus, the angle formed by both main bronchi does not exceed 100 °. An extension of this angle may indicate the development of a pathological (volumetric) process (tumor).

Above the left bronchus is the aortic arch, then the bronchus is located in front of the esophagus and descending aorta. The bronchi, in their shape and structure, represent a reduced copy of the respiratory throat. The main bronchi, dividing into ever smaller branches, form the so-called. bronchial tree.

Blood supply to the trachea is carried out from several arteries: from the lower thyroid, internal thoracic, as well as bronchi, bronchial branches of the thoracic aorta. Venous edema is directed into the venous plexus around the trachea, thyroid gland and bronchi.

The lymphatic vessels of the trachea carry lymph to the nearest paratracheal and paravertebral lymph nodes, as well as bifurcation nodes. Lymphatic vessels of the bronchi go to the parabronchial lymph nodes.

The innervation of the trachea and bronchi is provided directly from the vagus nerve and from its branch - the lower throat nerve, as well as nerves extending from the sympathetic trunk.
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Clinical anatomy of the trachea and bronchi

  1. 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;
  2. Clinical anatomy of the esophagus, trachea and bronchus
    Clinical anatomy of the esophagus, trachea and
  4. 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,
  5. 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
  6. 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
  7. 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,
  8. 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
  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. Physiology of the esophagus, trachea and bronchus
    Physiology of the Esophagus, Trachea and
  11. Injuries, foreign bodies of the esophagus, trachea and bronchus
    Injuries, foreign bodies of the esophagus, trachea and
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