Boys have abdominal breathing during the period. Features of the structure of the respiratory system in children

In children it occurs in the 3-4th week of gestation. The respiratory organs are formed from the rudiments of the foregut of the embryo: first - the trachea, bronchi, acini (functional units of the lungs), in parallel with which the cartilaginous frame of the trachea and bronchi is formed, then the circulatory and nervous systems of the lungs. By birth, the vessels of the lungs have already been formed, the airways are quite developed, but filled with fluid and cell secretions respiratory tract. After birth, with a cry and the baby's first breath, this fluid is absorbed and coughed up.

The surfactant system is of particular importance. Surfactant is a surfactant that is synthesized at the end of pregnancy and helps the lungs expand during the first breath. With the start of breathing, the inhaled air is immediately cleansed from dust and microbial agents in the nose due to biological active substances, mucus, bactericidal substances, secretory immunoglobulin A.

With age, a child's respiratory tract adapts to the conditions in which he must live. The nose of a newborn is relatively small, its cavities are poorly developed, the nasal passages are narrow, and the lower nasal passage is not yet formed. The cartilaginous skeleton of the nose is very soft. The mucous membrane of the nasal cavity is richly vascularized with blood vessels and lymphatic vessels. Around the age of four, the lower nasal passage is formed. The cavernous (cavernous) tissue of the child’s nose gradually develops. Therefore, nosebleeds are very rare in children under one year of age. It is almost impossible for them to breathe through their mouth, since the oral cavity occupies relatively big tongue, pushing the epiglottis posteriorly. Therefore, in acute rhinitis, when breathing through the nose is sharply difficult, the pathological process quickly descends into the bronchi and lungs.

The development of the paranasal sinuses also occurs after a year, so in children of the first year of life their inflammatory changes are rare. Thus, than smaller child, the more his nose is adapted to warming, humidifying and purifying the air.

The pharynx of a newborn baby is small and narrow. The pharyngeal ring of the tonsils is in the development stage. Therefore, the palatine tonsils do not extend beyond the edges of the arches of the palate. At the beginning of the second year of life, lymphoid tissue develops intensively, and the palatine tonsils begin to extend beyond the edges of the arches. By the age of four, the tonsils are well developed; under unfavorable conditions (infections of the ENT organs), their hypertrophy may appear.

The physiological role of the tonsils and everything pharyngeal ring- is the filtration and sedimentation of microorganisms coming from environment. In case of prolonged contact with a microbial agent, sudden cooling of the child protective function tonsils weaken, they become infected, and acute or chronic inflammation develops with a corresponding clinical picture.

Enlargement of the nasopharyngeal tonsils is most often associated with chronic inflammation, against the background of which respiratory failure, allergization and intoxication of the body are noted. Hypertrophy of the palatine tonsils leads to disorders neurological status children, they become inattentive and do poorly at school. With hypertrophy of the tonsils in children, a pseudocompensatory malocclusion is formed.

Most frequent illnesses of the upper respiratory tract in children there are acute rhinitis and sore throats.

The larynx in a newborn has a funnel-shaped structure, with soft cartilage. The glottis of the larynx is located at the level of the IV cervical vertebra, and in an adult at the level of the VII cervical vertebra. The larynx is relatively narrow, the mucous membrane covering it has well-developed blood and lymphatic vessels. Its elastic tissue is poorly developed. Sex differences in the structure of the larynx appear at puberty. Boys have a larynx in place thyroid cartilages it becomes sharper, and by the age of 13 it already looks like the larynx of an adult man. And in girls, by the age of 7-10, the structure of the larynx becomes similar to the structure of an adult woman.

Until 6-7 years of age, the glottis remains narrow. From the age of 12, boys' vocal cords become longer than girls'. Due to the narrow structure of the larynx, good development submucosal layer in children early age Its lesions are frequent (laryngitis), often accompanied by a narrowing (stenosis) of the glottis, and a picture of croup with difficulty breathing often develops.

The trachea is already formed by the time the baby is born. The upper edge of the se in newborns is located at the level of the IV cervical vertebra (in an adult at the level of the VII cervical vertebra).

The bifurcation of the trachea lies higher than in an adult. The mucous membrane of the trachea is delicate and richly vascularized. Its elastic tissue is poorly developed. The cartilaginous skeleton in children is soft, the lumen of the trachea narrows easily. In children, with age, the trachea gradually grows in length and width, but the overall growth of the body exceeds the growth of the trachea.

In progress physiological breathing the lumen of the trachea changes; during coughing it decreases by approximately 1/3 of its transverse and longitudinal size. There are many secreting glands in the mucous membrane of the trachea. Their secretion covers the surface of the trachea with a layer 5 microns thick; the speed of mucus movement from inside to outside (10-15 mm/min) is ensured by the ciliated epithelium.

Children often experience tracheal diseases such as tracheitis, in combination with damage to the larynx (laryngotracheitis) or bronchi (tracheobronchitis).

The bronchi are formed for the birth of the child. Their mucous membrane is richly supplied with blood vessels, covered with a layer of mucus, which moves from inside to outside at a speed of 0.25 - 1 cm/min. The right bronchus is like a continuation of the trachea, it is wider than the left. In children, unlike adults, the elastic and muscle fibers of the bronchi are poorly developed. Only with age do the length and width of the lumen of the bronchi increase. By the age of 12-13 years, the length and lumen of the main bronchi doubles compared to a newborn. With age, the ability of the bronchi to resist collapse also increases. The most common pathology in children is acute bronchitis, which is observed against the background of acute respiratory diseases. Relatively often, children develop bronchiolitis, which is facilitated by the narrowness of the bronchi. Around one year of age, it may develop bronchial asthma. Initially, it occurs against the background of acute bronchitis with a syndrome of complete or partial obstruction, bronchiolitis. Then the allergic component comes on.

The narrowness of the bronchioles also explains the frequent occurrence of pulmonary atelectasis in young children.

In a newborn baby, the weight of the lungs is small and amounts to approximately 50-60 g, this is 1/50 of its weight. Subsequently, the weight of the lungs increases 20 times. In newborns, the lung tissue is well vascularized, it contains a lot of loose connective tissue, and the elastic lung tissue is less developed. Therefore, emphysema is often observed in children with lung diseases. The acini, which is the functional respiratory unit of the lungs, is also underdeveloped. The alveoli of the lungs begin to develop only from the 4-6th week of a child’s life; their formation occurs up to 8 years. After 8 years, the lungs increase due to the linear size of the alveoli.

In parallel with the increase in the number of alveoli up to 8 years, the respiratory surface of the lungs increases.

In the development of the lungs, 4 periods can be distinguished:

I period - from birth to 2 years; intensive growth of lung alveoli;

II period - from 2 to 5 years; intensive development of elastic tissue, significant growth of bronchi with peribronchial inclusions of lymphoid tissue;

III period - from 5 to 7 years; final maturation of the acinus;

IV period - from 7 to 12 years; further increase in lung mass due to maturation lung tissue.

The right lung consists of three lobes: upper, middle and lower, and the left lung consists of two: upper and lower. At birth, the upper lobe of the left lung is less developed. By 2 years, the sizes of the individual lobes correspond to each other, as in adults.

In addition to the lobar division, the lungs also have a segmental division corresponding to the division of the bronchi. There are 10 segments in the right lung, and 9 in the left lung.

In children, due to the characteristics of aeration, drainage function and evacuation of secretions from the lungs, the inflammatory process is more often localized in the lower lobe (in the basal-apical segment - 6th segment). It is here that conditions for poor drainage in the supine position are created in infants. Another place of pure localization of inflammation in children is the 2nd segment upper lobe and the basal-posterior (10th) segment of the lower lobe. So-called paravertebral pneumonia develops here. The middle lobe is also often affected. Some lung segments: mid-lateral (4th) and mid-inferior (5th) - located in the area of bronchopulmonary lymph nodes. Therefore, when the latter become inflamed, the bronchi of these segments are compressed, causing a significant shutdown of the respiratory surface and the development of severe lung failure.

Functional features of breathing in children

The mechanism of the first breath in a newborn is explained by the fact that at the moment of birth the umbilical cord blood circulation stops. The partial pressure of oxygen (pO 2) decreases, the pressure increases carbon dioxide(pCO 2), blood acidity (pH) decreases. An impulse arises from peripheral receptors carotid artery and the aorta to the respiratory center of the central nervous system. Along with this, impulses from skin receptors go to the breathing center, as the conditions of the child’s stay in the environment change. He gets into more cold air with less humidity. These influences also irritate the respiratory center, and the child takes his first breath. Peripheral regulators of respiration are hema- and baroreceptors of the carotid and aortic formations.

The formation of breathing occurs gradually. In children in the first year of life, respiratory arrhythmia is often recorded. Premature babies often experience apnea (cessation of breathing).

Oxygen reserves in the body are limited, they last for 5-6 minutes. Therefore, a person must maintain this supply by constant breathing. From a functional point of view, there are two parts of the respiratory system: conductive (bronchi, bronchioles, alveoli) and respiratory (acini with afferent bronchioles), where gas exchange takes place between atmospheric air and the blood of the capillaries of the lungs. Diffusion of atmospheric gases occurs through the alveolar-capillary membrane due to the difference in gas pressure (oxygen) in the inhaled air and venous blood flowing through the lungs pulmonary artery from the right ventricle of the heart.

The pressure difference between alveolar oxygen and venous blood oxygen is 50 mmHg. Art., which ensures the transition of oxygen from the alveoli through the alveolar-capillary membrane into the blood. At this time, carbon dioxide is transferred from the blood, which is also in the blood under high pressure. Children have significant differences in external respiration compared to adults due to the ongoing development of the respiratory acini of the lungs after birth. In addition, children have numerous anastomoses between the bronchiolar and pulmonary arteries and capillaries, which is the main reason for the shunting (connection) of blood that bypasses the alveoli.

There are a number of indicators of external respiration that characterize its function: 1) pulmonary ventilation; 2) pulmonary volume; 3) breathing mechanics; 4) pulmonary gas exchange; 5) gas composition arterial blood. The calculation and evaluation of these indicators is carried out in order to determine functional state respiratory organs and reserve capabilities in children of different ages.

Respiratory examination

This is a medical procedure, and nursing staff must be able to prepare for this test.

It is necessary to find out the timing of the onset of the disease, the main complaints and symptoms, whether the child took any medications and how they affected the dynamics clinical symptoms, what are the complaints today. This information should be obtained from the mother or child's caregiver.

In children, most lung diseases begin with a runny nose. In this case, in the diagnosis it is necessary to clarify the nature of the discharge. The second leading symptom of damage to the respiratory system is cough, the nature of which determines the presence of a particular disease. The third symptom is shortness of breath. In young children with shortness of breath, nodding movements of the head and swelling of the wings of the nose are visible. In older children, retraction may be noticed yielding places chest, abdominal retraction, forced position (sitting with support from hands - for bronchial asthma).

The doctor examines the child’s nose, mouth, pharynx and tonsils, and differentiates the existing cough. Croup in a child is accompanied by laryngeal stenosis. A distinction is made between true (diphtheria) croup, when the narrowing of the larynx occurs due to diphtheritic films, and false croup(subglottic laryngitis), which occurs as a result of spasm and swelling against the background of an acute inflammatory disease of the larynx. True croup develops gradually, over days, false croup - unexpectedly, often at night. The voice with croup can reach aphonia, with sharp breakthroughs of sonorous notes.

Cough with whooping cough in the form of paroxysm (paroxysmal) with reprises (prolonged high inhalation) is accompanied by redness of the face and vomiting.

Bitonal cough (a rough main tone and a musical second tone) is observed with enlargement of the bifurcation lymph nodes and tumors in this place. A painful dry cough is observed with pharyngitis and nasopharyngitis.

It is important to know the dynamics of changes in cough, whether the cough bothered you before, what happened to the child and how the process in the lungs ended, whether the child had contact with a patient with tuberculosis.

When examining a child, the presence of cyanosis is determined, and if it is present, its nature. Pay attention to increased cyanosis, especially around the mouth and eyes, when the child screams or exercises. Children under 2-3 months of age may have foamy discharge from the mouth upon examination.

Pay attention to the shape of the chest and the type of breathing. The abdominal type of breathing remains in boys into adulthood. In girls, from the age of 5-6 years it appears breast type breathing.

Count up the number breathing movements per minute. It depends on the age of the child. In young children, the number of respirations is counted at rest when they are sleeping.

By the frequency of breathing and its relationship with the pulse, the presence or absence of respiratory failure. By the nature of shortness of breath, one or another damage to the respiratory system is judged. Dyspnea is inspiratory when the passage of air in the upper respiratory tract is difficult (croup, foreign body, cysts and tumors of the trachea, congenital narrowing of the larynx, trachea, bronchi, retropharyngeal abscess etc.). When a child inhales, there is retraction of the epigastric region, intercostal spaces, subclavian space, jugular fossa, tension m. sternocleidomastoideus and other accessory muscles.

Shortness of breath can also be expiratory, when the chest is swollen and almost does not participate in breathing, and the stomach, on the contrary, actively participates in the act of breathing. In this case, exhalation is longer than inhalation.

However, there is also mixed shortness of breath - expiratory-inspiratory, when the muscles of the abdomen and chest take part in the act of breathing.

Splint shortness of breath (expiratory shortness of breath) may also be observed, which occurs as a result of compression of the root of the lung by enlarged lymph nodes, infiltrates, the lower part of the trachea and bronchi; the breath is free.

Dyspnea is common in newborns with respiratory distress syndrome.

Palpation of the child's chest is carried out with both hands to determine its soreness, resistance (firmness), and elasticity. The thickness is also measured skin fold on symmetrical areas of the chest to determine inflammation on one side. On the affected side, thickening of the skin fold is noted.

Next they move on to percussion of the chest. Normally, children of all ages receive the same percussion on both sides. At various lesions lungs, the percussion sound changes (dull, boxy, etc.). Topographic percussion is also performed. There are age-related standards for the location of the lungs, which may change due to pathology.

After conducting comparative and topographic percussion perform auscultation. Normally, in children up to 3-6 months, slightly weakened breathing is heard, from 6 months to 5-7 years - puerile breathing, and in children over 10-12 years old it is often transitional - between puerile and vesicular.

With lung pathology, the breathing pattern often changes. Against this background, dry and moist rales and pleural friction noise can be heard. To determine compaction (infiltration) in the lungs, a method for assessing bronchophony is often used, when the voice is heard under symmetrical areas of the lungs. At lung compaction on the affected side, increased bronchophony is heard. With caverns and bronchiectasis, increased bronchophony may also be observed. Weakening of bronchophony is noted in the presence of fluid in the pleural cavity (effusion pleurisy, hydrothorax, hemothorax) and (pneumothorax).

Instrumental studies

For lung diseases, the most common examination is x-ray. In this case, radiography or fluoroscopy is performed. Each of these studies has its own indications. During an X-ray examination of the lungs, attention is paid to the transparency of the lung tissue and the appearance of various dark spots.

Special studies include bronchography - a diagnostic method based on the injection of a contrast agent into the bronchi.

For mass studies, fluorography is used, a method based on the study of the lungs using a special X-ray attachment and output to photographic film.

Other methods are used computed tomography, which allows you to examine in detail the condition of the mediastinal organs, the root of the lungs, to see changes in the bronchi and bronchiectasis. When using nuclear magnetic resonance, detailed research tissues of the trachea, large bronchi, you can see the vessels, their relationship with the respiratory tract.

An effective diagnostic method is endoscopic examination, including anterior and posterior rhinoscopy (examination of the nose and its passages) using nasal and nasopharyngeal speculum. The lower part of the pharynx is examined using special spatulas (direct laryngoscopy), and the larynx is examined using a laryngeal mirror (laryngoscope).

Bronchoscopy, or tracheobronchoscopy, is a method based on the use of fiber optics. This method is used to identify and remove foreign bodies from the bronchi and trachea, drainage of these formations (suction of mucus) and their biopsy, and administration of medications.

There are also methods for studying external respiration based on graphic recording respiratory cycles. These records are used to judge the function of external respiration in children over 5 years of age. Then pneumotachometry is performed using a special apparatus, which makes it possible to determine the state of bronchial conductivity. The state of ventilation function in sick children can be determined using the peak flowmetry method.

From laboratory tests a method is used to study gases (O 2 and CO 2) in the capillary blood of a patient using a micro-Astrup apparatus.

Oxygenography is performed using photoelectric measurement of light absorption through the auricle.

Among the stress tests, a test with holding the breath while inhaling (Streny test) and a test with physical activity are used. When squatting (20-30 times) in healthy children, there is no decrease in blood oxygen saturation. An oxygen exhalation test is done when breathing on oxygen is switched on. In this case, the saturation of exhaled air increases by 2-4% within 2-3 minutes.

Examine the patient's sputum laboratory methods: number, content of leukocytes, erythrocytes, squamous epithelial cells, mucus strands.

By the time the child is born, the morphological structure is still imperfect. Intensive growth and differentiation of the respiratory organs continues during the first months and years of life. The formation of the respiratory organs ends on average by 7 years, and subsequently only their size increases. All airways in a child are significantly smaller and have narrower openings than in an adult. Features of their morphol. structures in children of the first years of life are:

1) thin, delicate, easily wounded dry mucous membrane with insufficient development of glands, with reduced production of secretory immunoglobulin A (SIgA) and surfactant deficiency;

2) rich vascularization of the submucosal layer, represented mainly by loose fiber and containing few elastic and connective tissue elements;

3) softness and pliability of the cartilaginous frame of the lower respiratory tract, the absence of elastic tissue in them and in the lungs.

Nose and nasopharyngeal space . In young children, the nose and nasopharyngeal space are small, short, flattened due to insufficient development of the facial skeleton. The shells are thick, the nasal passages are narrow, the lower one is formed only by 4 years. Cavernous tissue develops by 8-9 years.

Accessory nasal cavities . By the birth of the child, only the maxillary sinuses are formed; The frontal and ethmoid are open protrusions of the mucous membrane, taking shape in the form of cavities only after 2 years; the main sinus is absent. All nasal cavities develop completely by the age of 12-15 years.

Nasolacrimal duct . It is short, its valves are underdeveloped, the outlet is located close to the corner of the eyelids, which facilitates the spread of infection from the nose to the conjunctival sac.

Pharynx . In young children, it is relatively wide; the tonsils are clearly visible at birth, but do not protrude due to well-developed arches. Their crypts and vessels are poorly developed, which to some extent explains rare diseases sore throat in the first year of life. By the end of the first year, the lymphoid tissue of the tonsils, including the nasopharyngeal (adenoids), often hyperplasias, especially in children with diathesis. Their barrier function at this age is low, like that of lymph nodes. The overgrown lymphoid tissue is populated by viruses and microbes, and foci of infection are formed - adenoiditis and chronic tonsillitis.

Thyroid cartilages In young children they form a blunt rounded angle, which becomes sharper in boys after 3 years. From the age of 10, the characteristic male larynx is formed. The true vocal cords of children are shorter than those of adults, which explains the pitch and timbre of a child's voice.

Trachea. In children in the first months of life, it is often funnel-shaped; at older ages, cylindrical and conical shapes predominate. Its upper end is located in newborns much higher than in adults (at the level of the IV cervical vertebrae), and gradually lowers, like the level of the tracheal bifurcation (from the III thoracic vertebra in a newborn to V -VI at 12-14 years). The tracheal framework consists of 14-16 cartilaginous half-rings connected posteriorly by a fibrous membrane (instead of an elastic end plate in adults). The membrane contains many muscle fibers, the contraction or relaxation of which changes the lumen of the organ. The child’s trachea is very mobile, which, along with the changing lumen and softness of the cartilage, sometimes leads to a slit-like collapse during exhalation (collapse) and is the cause of expiratory shortness of breath or rough snoring breathing (congenital stridor). Symptoms of stridor usually disappear by age 2 as the cartilage becomes denser.

Bronchial tree . By the time of birth, the bronchial tree is formed. The size of the bronchi increases rapidly in the first year of life and during puberty. They are based on cartilaginous semirings in early childhood, which do not have a closing elastic plate and are connected by a fibrous membrane containing muscle fibers. The cartilage of the bronchi is very elastic, soft, springy and easily displaced. Right main bronchus It is usually an almost direct continuation of the trachea, therefore it is in it that foreign bodies are most often found. The bronchi, like the trachea, are lined with multirow cylindrical epithelium, the ciliated apparatus of which is formed after the birth of the child.

Due to an increase in the thickness of the submucosal layer and mucous membrane by 1 mm, the total area of the bronchial lumen of a newborn decreases by 75% (in an adult - by 19%). Active bronchial motility is insufficient due to poor development of muscles and ciliated epithelium. Incomplete myelination of the vagus nerve and underdevelopment of the respiratory muscles contribute to the weakness of the cough impulse in a small child; Infected mucus accumulating in the bronchial tree clogs the lumens of the small bronchi, promotes atelectasis and infection of the lung tissue. functional feature bronchial tree of a small child is insufficient performance of the drainage and cleansing function.

Lungs. In children, as in adults, the lungs have a segmental structure. The segments are separated from each other by narrow grooves and layers of connective tissue (lobular lung). The main structural unit is the acini, but its terminal bronchioles end not in a cluster of alveoli, as in an adult, but in a sac (sacculus). New alveoli are gradually formed from the “lace” edges of the latter, the number of which in a newborn is 3 times less than in an adult. The diameter of each alveoli increases (0.05 mm in a newborn, 0.12 mm at 4-5 years, 0.17 mm at 15 years). At the same time, the vital capacity of the lungs increases. The interstitial tissue in a child's lung is loose, rich in blood vessels, fiber, and contains very little connective tissue and elastic fibers. In this regard, the lungs of a child in the first years of life are more full-blooded and less airy than those of an adult. Underdevelopment of the elastic framework of the lungs contributes to both the occurrence of emphysema and atelectasis of the lung tissue.

The tendency to atelectasis is enhanced by a deficiency of surfactant, a film that regulates alveolar surface tension and is produced by alveolar macrophages. It is this deficiency that causes insufficient expansion of the lungs in premature infants after birth (physiological atelectasis).

Pleural cavity . In a child, it is easily extensible due to the weak attachment of the parietal layers. The visceral pleura, especially in newborns, is relatively thick, loose, folded, contains villi and outgrowths, most pronounced in the sinuses and interlobar grooves.

Lung root . Consists of large bronchi, vessels and lymph nodes (tracheobronchial, bifurcation, bronchopulmonary and around large vessels). Their structure and function are similar to peripheral lymph nodes. They easily respond to the introduction of infection. The thymus gland (thymus) is also located in the mediastinum, which at birth has large sizes and normally decreases gradually during the first two years of life.

Diaphragm. Due to the characteristics of the chest, the diaphragm plays a large role in the breathing mechanism of a small child, providing depth of inspiration. The weakness of its contractions partly explains the extremely shallow breathing of a newborn. Main functions physiological features respiratory organs are: shallow breathing; physiological shortness of breath (tachypnea), often irregular breathing rhythm; tension of gas exchange processes and easy occurrence of respiratory failure.

1. The depth of breathing, absolute and relative volumes of one respiratory act in a child are significantly less than in an adult. When screaming, the volume of breathing increases 2-5 times. The absolute value of the minute volume of respiration is less than that of an adult, and the relative value (per 1 kg of body weight) is much greater.

2. The younger the child, the higher the breathing rate, it compensates for the small volume of each respiratory act and provides the child’s body with oxygen. Rhythm instability and short (3-5 min) pauses in breathing (apnea) in newborns and premature infants are associated with incomplete differentiation of the respiratory center and its hypoxia. Oxygen inhalation usually eliminates respiratory arrhythmia in these children.

3. Gas exchange in children is carried out more vigorously than in adults, due to the rich vascularization of the lungs, blood flow speed, and high diffusion capacity. At the same time, the function of external respiration in a small child is disrupted very quickly due to insufficient excursion of the lungs and straightening of the alveoli.

The respiratory rate of a newborn child is 40 - 60 per minute, a one-year-old child is 30 -35, 5 - 6 years old is 20 -25, 10 years old is 18 - 20, an adult is 15 - 16 per minute.

Percussion tone healthy child the first years of life, as a rule, tall, clear, with a slightly boxy tint. When screaming, it can change - up to distinct tympanitis at maximum inspiration and shortening during exhalation.

The normal respiratory sounds heard depend on age: up to one year in a healthy child, breathing is weakened vesicular due to its superficial nature; at the age of 2 - 7 years, puerile (children's) breathing is heard, more distinct, with a relatively louder and longer (1/2 of inhalation) exhalation. In school-age children and adolescents, breathing is the same as in adults - vesicular.

The leading role in the origin of this syndrome is played by a deficiency of surfactant - a surfactant that lines the inside of the alveoli and prevents their collapse. Surfactant synthesis changes in prematurely born children, and various adverse effects on the fetus also affect the fetus, leading to hypoxia and hemodynamic disorder in the lungs. There is evidence of the participation of prostaglandins E in the pathogenesis of respiratory distress syndrome. These biologically active substances indirectly reduce the synthesis of surfactant, have a vasopressor effect on the blood vessels of the lungs, and prevent the closure of the ductus arteriosus and the normalization of blood circulation in the lungs.

There are several stages in the development of the respiratory system:

Stage 1 – up to 16 weeks intrauterine development the formation of bronchial glands occurs.

From the 16th week - the recanalization stage - cellular elements begin to produce mucus and fluid and, as a result, the cells are completely displaced, the bronchi acquire lumen, and the lungs become hollow.

Stage 3 - alveolar - begins from 22 - 24 weeks and continues until the birth of the child. During this period, the formation of the acini, alveoli, and the synthesis of surfactant occurs.

By the time of birth, there are about 70 million alveoli in the fetal lungs. From 22-24 weeks, differentiation of alveolocytes begins - the cells lining inner surface alveoli

There are 2 types of alveolocytes: type 1 (95%), type 2 – 5%.

Surfactant is a substance that prevents alveoli from collapsing due to changes in surface tension.

It lines the alveoli from the inside thin layer, during inspiration, the volume of the alveoli increases, surface tension increases, which leads to respiratory resistance.

During exhalation, the volume of the alveoli decreases (more than 20-50 times), surfactant prevents their collapse. Since 2 enzymes are involved in the production of surfactant, they are activated by different dates gestation (at the latest from 35-36 weeks), it is clear that the shorter the child’s gestational age, the more pronounced the surfactant deficiency and the higher the likelihood of developing bronchopulmonary pathology.

Surfactant deficiency also develops in mothers with preeclampsia, during complicated pregnancy, caesarean section. The immaturity of the surfactant system is manifested by the development respiratory distress– syndrome.

Surfactant deficiency leads to collapse of the alveoli and the formation of atelectasis, as a result of which gas exchange function is disrupted, pressure in the pulmonary circulation increases, which leads to the persistence of fetal circulation and the functioning of the patent ductus arteriosus and oval window.

As a result, hypoxia and acidosis develop, vascular permeability increases and the liquid part of the blood with proteins sweats into the alveoli. Proteins are deposited on the wall of the alveoli in the form of half rings - hyaline membranes. This leads to impaired diffusion of gases and the development of severe respiratory failure, which is manifested by shortness of breath, cyanosis, tachycardia, and the participation of auxiliary muscles in the act of breathing.

The clinical picture develops within 3 hours from the moment of birth and changes increase within 2-3 days.

AFO of the respiratory organs

By the time a child is born, the respiratory system reaches morphological maturity and can perform the function of breathing.
In a newborn, the respiratory tract is filled with a liquid that has low viscosity and a small amount of protein, which ensures its rapid absorption after the birth of the child through the lymphatic and blood vessels. In the early neonatal period, the child adapts to extrauterine existence.
After 1 inhalation, a short inspiratory pause occurs, lasting 1-2 seconds, after which exhalation occurs, accompanied by a loud cry of the child. In this case, the first respiratory movement in a newborn is carried out according to the type of gasping (inspiratory “flash”) - this is deep breath with difficulty breathing. Such breathing persists in healthy full-term infants until the first 3 hours of life. In a healthy newborn baby, with the first exhalation, most of the alveoli expand, and at the same time, vasodilation occurs. Complete expansion of the alveoli occurs within the first 2-4 days after birth.
The mechanism of the first breath. The main trigger is hypoxia, which occurs as a result of clamping of the umbilical cord. After ligation of the umbilical cord, oxygen tension in the blood drops, carbon dioxide pressure increases and pH decreases. In addition, for a newborn child great influence has an environmental temperature that is lower than in the womb. Contraction of the diaphragm creates negative pressure in chest cavity, which ensures easier entry of air into the respiratory tract.

A newborn child has well-expressed defensive reflexes– cough and sneezing. Already in the first days after the birth of a child, the Hering-Breuer reflex functions, which, at threshold stretching of the pulmonary alveoli, leads to the transition of inhalation to exhalation. In an adult, this reflex occurs only with very strong stretching of the lungs.

Anatomically, the upper, middle and lower respiratory tract are distinguished. The nose is relatively small at the time of birth, the nasal passages are narrow, the lower nasal passage and the nasal concha, which are formed by the age of 4, are absent. Submucosal tissue is poorly developed (matures by 8-9 years), cavernous or cavernous tissue is underdeveloped up to 2 years (as a result, young children do not experience nosebleeds). The nasal mucosa is delicate, relatively dry, and rich in blood vessels. Due to the narrowness of the nasal passages and the abundant blood supply to their mucous membrane, even minor inflammation causes difficulty breathing through the nose in young children. Breathing through the mouth is impossible in children in the first half of life, since the large tongue pushes the epiglottis backward. The exit from the nose - the choanae - is especially narrow in young children, which is often the cause of long-term disruption of nasal breathing in them.

The paranasal sinuses in young children are very poorly developed or completely absent. As the facial bones increase in size ( upper jaw) and teeth erupt, the length and width of the nasal passages and the volume of the paranasal sinuses increase. These features explain the rarity of diseases such as sinusitis, frontal sinusitis, ethmoiditis in early childhood. A wide nasolacrimal duct with underdeveloped valves contributes to the transfer of inflammation from the nose to the mucous membrane of the eyes.

The pharynx is narrow and small. The lymphopharyngeal ring (Waldeyer-Pirogov) is poorly developed. It consists of 6 tonsils:

2 palatines (between the anterior and posterior palatines)

2 tubes (near the Eustachian tubes)

1 throat (in the upper part of the nasopharynx)

1 lingual (in the area of the root of the tongue).

The palatine tonsils are not visible in newborns; by the end of the 1st year of life they begin to protrude due to palatine arches. By the age of 4-10 years, the tonsils are well developed and their hypertrophy can easily occur. During puberty, the tonsils begin to undergo reverse development. The Eustachian tubes in young children are wide, short, straight, located horizontally and at horizontal position child, the pathological process from the nasopharynx easily spreads to the middle ear, causing the development of otitis media. With age they become narrow, long, and tortuous.

The larynx has a funnel shape. The glottis is narrow and located high (at the level of the 4th cervical vertebra, and in adults - at the level of the 7th cervical vertebra). Elastic tissue is poorly developed. The larynx is relatively longer and narrower than in adults; its cartilage is very pliable. With age, the larynx acquires a cylindrical shape, becomes wide and descends 1-2 vertebrae lower. The false vocal cords and mucous membrane are delicate, rich in blood and lymphatic vessels, elastic tissue is poorly developed. The glottis in children is narrow. Young children's vocal cords are shorter than those of older children, which is why they have a high-pitched voice. From the age of 12, boys' vocal cords become longer than girls'.

The bifurcation of the trachea lies higher than in an adult. The cartilaginous frame of the trachea is soft and easily narrows the lumen. Elastic tissue is poorly developed, the mucous membrane of the trachea is tender and richly supplied with blood vessels. The growth of the trachea occurs in parallel with the growth of the body, most intensively in the 1st year of life and during puberty.

The bronchi are richly supplied with blood, muscle and elastic fibers in young children are underdeveloped, and the lumen of the bronchi is narrow. Their mucous membrane is richly vascularized.
The right bronchus is like a continuation of the trachea; it is shorter and wider than the left. This explains frequent hit foreign body into the right main bronchus.
The bronchial tree is poorly developed.
There are 1st order bronchi - main, 2nd order - lobar (3 on the right, 2 on the left), 3rd order - segmental (10 on the right, 9 on the left). The bronchi are narrow, their cartilage is soft. Muscle and elastic fibers in children of the 1st year of life are not yet sufficiently developed, the blood supply is good. The bronchial mucosa is lined with ciliated epithelium, which provides mucociliary clearance, which plays a major role in protecting the lungs from various pathogens from the upper respiratory tract and has an immune function (secretory immunoglobulin A). The tenderness of the bronchial mucosa and the narrowness of their lumen explain the frequent occurrence of bronchiolitis with the syndrome of complete or partial obstruction and pulmonary atelectasis in young children.

Lung tissue is less airy, elastic tissue is underdeveloped. In the right lung there are 3 lobes, in the left 2. Then the lobar bronchi are divided into segmental ones. A segment is an independently functioning unit of the lung, with its apex directed towards the root of the lung, and has an independent artery and nerve. Each segment has independent ventilation, a terminal artery and intersegmental septa made of elastic connective tissue. The segmental structure of the lungs is already well expressed in newborns. There are 10 segments in the right lung, and 9 in the left. The upper left and right lobes are divided into three segments - 1st, 2nd and 3rd, middle right lobe- into two segments - 4th and 5th. In the left light medium The lobe corresponds to the lingular lobe, also consisting of two segments - the 4th and 5th. The lower lobe of the right lung is divided into five segments - 6, 7, 8, 9 and 10th, the left lung - into four segments - 6, 7, 8 and 9th. The acini are underdeveloped, the alveoli begin to form from 4 to 6 weeks of life and their number quickly increases within 1 year, increasing up to 8 years.

The oxygen requirement in children is much higher than in adults. Thus, in children of the 1st year of life, the need for oxygen per 1 kg of body weight is about 8 ml/min, in adults - 4.5 ml/min. The shallow nature of breathing in children is compensated by a high breathing frequency, the participation of most of the lungs in breathing

In the fetus and newborn, hemoglobin F predominates, which has an increased affinity for oxygen, and therefore the dissociation curve of oxyhemoglobin is shifted to the left and up. Meanwhile, in a newborn, like in a fetus, red blood cells contain extremely little 2,3-diphosphoglycerate (2,3-DPG), which also causes less saturation of hemoglobin with oxygen than in an adult. At the same time, in the fetus and newborn, oxygen is more easily transferred to the tissues.

In healthy children, depending on age, different breathing patterns are determined:

a) vesicular - exhalation is one third of inhalation.

b) puerile breathing - enhanced vesicular

c) hard breathing - exhalation is more than half of the inhalation or equal to it.

d) bronchial breathing - exhalation is longer than inhalation.

It is also necessary to note the sonority of breathing (normal, increased, weakened). In children of the first 6 months. breathing is weakened. After 6 months up to 6 years of age, breathing is puerile, and from 6 years of age - vesicular or intensely vesicular (one third of inhalation and two thirds of exhalation are heard), it is heard evenly over the entire surface.

Respiratory rate (RR)

	Frequency per minute
Premature
Newborn

Stange test - holding your breath while inhaling (6-16 years old - from 16 to 35 seconds).

Gench's test - holding your breath while exhaling (N - 21-39 sec).

The respiratory system is a collection of organs consisting of the respiratory tract (nose, pharynx, trachea, bronchi), lungs (bronchial tree, acini), as well as muscle groups that promote contraction and relaxation of the chest. Breathing provides the body's cells with oxygen, which in turn convert it into carbon dioxide. This process occurs in the pulmonary circulation.

The formation and development of the child’s respiratory system begins during the 3rd week of a woman’s pregnancy. Formed from three primordia:

Splanchnotome.
Mesenchyme.
Epithelium of the foregut.

The pleural mesothelium develops from the visceral and parietal layers of the splanchnotome. It is presented in a single layer flat epithelium(polygonal cells), lining the entire surface of the pulmonary system, separating it from other organs. External surface The leaf is covered with microcilia that produce serous fluid. It is necessary for the two layers of pleura to slide between each other during inhalation and exhalation.

From the mesenchyme, namely the germ layer of the mesoderm, cartilage, muscle and connective tissue structures, and blood vessels are formed. The bronchial tree, lungs, and alveoli develop from the epithelium of the foregut.

In prenatal period The airways and lungs are filled with fluid, which is removed during childbirth with the first breath, and is also absorbed by the lymph system and partially into the blood vessels. Breathing is carried out by maternal blood enriched with oxygen through the umbilical cord.

By the eighth month of gestation, pneumocytes produce a surfactant - surfactant. It lines the inner surface of the alveoli, prevents them from collapsing and sticking together, and is located at the air-liquid interface. Protects against harmful agents with the help of immunoglobulins and macrophages. Insufficient secretion or absence of surfactant threatens the development of respiratory distress syndrome.

A feature of the respiratory system in children is its imperfection. The formation and differentiation of tissues and cellular structures is carried out in the first years of life and up to seven years.

Structure

Over time, the child’s organs adapt to the environment in which he will live, and the necessary immune and glandular cells are formed. In a newborn, the respiratory tract, unlike an adult body, has:

Narrower clearance.
Short stroke lengths.
Many vascular vessels in a limited area of the mucosa.
The delicate, easily traumatized architectonics of the lining membranes.
Loose structure of lymphoid tissue.

Upper paths

Baby's nose small size, its passages are narrow and short, so the slightest swelling can lead to obstruction, which will complicate the sucking process.

The structure of the upper tract in a child:

Two nasal sinuses are developed - the upper and middle, the lower one will be formed by the age of four. The cartilage frame is soft and pliable. The mucous membrane has an abundance of blood and lymphatic vessels, and therefore minor manipulation can lead to injury. Rarely noted nosebleed– this is due to undeveloped cavernous tissue (it will be formed by the age of 9). All other cases of bleeding from the nose are considered pathological.
The maxillary sinuses, frontal and ethmoid sinuses are not closed, protrude the mucous membrane, are formed by 2 years of age, cases are rare inflammatory lesions. Thus, the shell is more adapted to cleansing and humidifying the inhaled air. Full development of all sinuses occurs by age 15.
The nasolacrimal duct is short, exits in the corner of the eye, close to the nose, which ensures rapid upward spread of inflammation from the nose to the lacrimal sac and the development of polyetiological conjunctivitis.
The pharynx is short and narrow, which allows it to quickly become infected through the nose. At the level between the oral cavity and the pharynx there is a nasopharyngeal ring-shaped Pirogov-Waldeyer formation, consisting of seven structures. The concentration of lymphoid tissue protects the entrance to the respiratory and digestive organs from infectious agents, dust, and allergens. Features of the structure of the ring: poorly formed tonsils, adenoids, they are loose, susceptible to colonization of inflammatory agents in their crypts. Chronic foci of infection, frequent respiratory diseases, sore throats, and difficulty in nasal breathing occur. These children develop neurological disorders and usually walk with open mouth and are less amenable to schooling.
The epiglottis is scapula-shaped, relatively wide and short. During breathing, it rests on the root of the tongue - it opens the entrance to lower paths, during the period of eating - prevents foreign bodies from entering the respiratory tract.

Lower Paths

The larynx of a newborn is located higher than that of an adult and is very mobile due to the muscular frame. It looks like a funnel with a diameter of 0.4 cm, the narrowing is directed towards the vocal cords. The chords are short, which explains the high timbre of the voice. With slight swelling, during acute respiratory diseases, symptoms of croup and stenosis occur, which are characterized by heavy, wheezing breathing with the inability to take a full breath. As a result, hypoxia develops. The laryngeal cartilages are rounded, their sharpening in boys occurs by the age of 10–12 years.

At the time of birth, the trachea is already formed, located at the level of the 4th cervical vertebra, mobile, funnel-shaped, then acquires a cylindrical appearance. The lumen is significantly narrowed, unlike in an adult; there are few glandular areas in it. When coughing, it can shrink by a third. Considering anatomical features, during inflammatory processes, narrowing and the appearance of a barking cough and symptoms of hypoxia (cyanosis, shortness of breath) are inevitable. The tracheal framework consists of cartilaginous half-rings, muscle structures, and a connective tissue membrane. The bifurcation at birth is higher than in older children.

The bronchial tree is a continuation of the tracheal bifurcation and is divided into the right and left bronchus. The right one is wider and shorter, the left one is narrower and longer. The ciliated epithelium is well developed, producing physiological mucus that cleanses the bronchial lumen. Mucus moves outward with cilia at a speed of up to 0.9 cm per minute.

A feature of the respiratory system in children is a weak cough impulse, due to poorly developed torso muscles, incomplete myelin coating nerve fibers tenth pair cranial nerves. As a result, infected sputum does not pass away, accumulates in the lumen of bronchi of different sizes and becomes clogged with thick secretions. The structure of the bronchus contains cartilaginous rings, with the exception of the terminal sections, which consist only of smooth muscle. When they are irritated, a sharp narrowing of the passage may occur - an asthmatic picture appears.

The lungs are an air tissue, their differentiation continues until the age of 9, they consist of:

Lobes (right of three, left of two).
Segments (right – 10, left – 9).
Dolek.

The bronchioles end in a sac in the baby. As the child grows, lung tissue grows, the sacs turn into alveolar clusters, and vital capacity indicators increase. Active development from the 5th week of life. Birth weight paired organ is 60–70 grams, well supplied with blood and vascularized with lymph. Thus, it is full-blooded, and not airy as in older people. The important point is that the lungs are not innervated, inflammatory reactions are painless, and in this case, a serious illness can be missed.

Due to the anatomical and physiological structure, pathological processes develop in the basal regions, cases of atelectasis and emphysema are common.

Functional Features

The first breath is carried out due to a decrease in oxygen in the blood of the fetus and an increase in the level of carbon dioxide, after clamping the umbilical cord, as well as a change in living conditions - from warm and humid to cold and dry. Signals travel along nerve endings to the central nervous system and then to the respiratory center.

Features of respiratory function in children:

Conducting air.
Cleaning, warming, moisturizing.
Saturation with oxygen and purification from carbon dioxide.
Protective immune function, synthesis of immunoglobulins.
Metabolism – synthesis of enzymes.
Filtration – dust, blood clots.
Lipid and water metabolism.
Shallow breaths.
Tachypnea.

In the first year of life, respiratory arrhythmia occurs, which is considered normal, but its persistence and the occurrence of apnea after one year of age is fraught with respiratory arrest and death.

The frequency of breathing movements directly depends on the age of the baby - the younger, the more often the breath is taken.

NPV norm:

Newborn 39–60/minute.
1–2 years – 29–35/min.
3–4 years – 23–28/min.
5–6 years – 19–25/min.
10 years – 19–21/min.
Adult – 16–21/min.

Taking into account the characteristics of the respiratory system in children, the attentiveness and awareness of parents, timely examination, therapy reduces the risk of transition to chronic stage illness and serious complications.

The respiratory organs are several organs united into a single bronchopulmonary system. It consists of two sections: the respiratory tract, through which air passes; the lungs themselves. The respiratory tract is usually divided into: upper respiratory tract - nose, paranasal sinuses, pharynx, Eustachian tubes and some other formations; the lower respiratory tract - the larynx, the bronchial system from the largest bronchus in the body - the trachea to its smallest branches, which are usually called bronchioles. Functions of the respiratory tract organs in the body Respiratory tract: conduct air from the atmosphere to the lungs; clean air masses from dust pollution; protect the lungs from harmful effects(some bacteria, viruses, foreign particles, etc. settle on the mucous membrane of the bronchi and are then removed from the body); warm and humidify the inhaled air. The lungs themselves look like many small air-inflated sacs (alveoli), interconnected and similar to bunches of grapes. The main function of the lungs is the process of gas exchange, that is, absorption from atmospheric air oxygen - a gas vital for normal, coordinated work all systems of the body, as well as the release of exhaust gases into the atmosphere, especially carbon dioxide. All these essential functions respiratory organs can be seriously impaired in diseases of the bronchopulmonary system. The respiratory organs of children are different from the respiratory organs of adults. These structural features and functions of the bronchopulmonary system must be taken into account when carrying out hygienic, preventive and therapeutic measures in a child. In a newborn, the respiratory tract is narrow, the mobility of the chest is limited due to the weakness of the chest muscles. Breathing is frequent - 40-50 times per minute, its rhythm is unstable. With age, the frequency of respiratory movements decreases and is 30-35 times at the age of one year, at 3 years -25-30, and at 4-7 years old - 22-26 times per minute. The depth of breathing and pulmonary ventilation increase by 2-2.5 times. Hoc is " watchdog» respiratory tract. The nose is the first to take on the attack of all harmful external influences. The nose is the center of information about the state of the surrounding atmosphere. It has a complex internal configuration and performs various functions: air passes through it; It is in the nose that the inhaled air is heated and humidified to the required level. internal environment organism parameters; the main part is deposited on the nasal mucosa first atmospheric pollution, microbes and viruses; In addition, the nose is an organ that provides the sense of smell, that is, it has the ability to sense odors. What ensures a child breathes normally through the nose? Normal nasal breathing extremely important for children of any age. It is a barrier to infection entering the respiratory tract, and therefore to the occurrence of bronchopulmonary diseases. Well-warmed clean air is a guarantee of protection against colds. In addition, the sense of smell develops in the child an idea of external environment, is protective in nature, shapes the attitude towards food and appetite. Nasal breathing is physiologically correct breathing. It is necessary to ensure that the child breathes through his nose. Breathing through the mouth in the absence or severe difficulty of nasal breathing is always a sign of a nasal disease and requires special treatment. Features of the nose in children The nose in children has a number of features. The nasal cavity is relatively small. The smaller the child, the smaller cavity nose The nasal passages are very narrow. The nasal mucosa is loose and well supplied with blood vessels, so any irritation or inflammation leads to rapid swelling and a sharp decrease in the lumen of the nasal passages, up to their complete obstruction. Nasal mucus, which is constantly produced by the mucous glands of the child’s nose, is quite thick. Mucus often stagnates in the nasal passages, dries out and leads to the formation of crusts, which, blocking the nasal passages, also contribute to the disruption of nasal breathing. At the same time, the child begins to “sniff” through his nose or breathe through his mouth. What can lead to impaired nasal breathing? Impaired breathing through the nose can cause shortness of breath and other respiratory disorders in children in the first months of life. U infants the act of sucking and swallowing is disrupted, the baby begins to worry, abandons the breast, remains hungry, and if nasal breathing is absent for a long time, the child may even gain worse weight. Severe difficulty in nasal breathing leads to hypoxia - disruption of the oxygen supply to organs and tissues. Children who breathe poorly through their nose develop worse and lag behind their peers in mastering the school curriculum. Lack of nasal breathing can even lead to increased intracranial pressure and dysfunction of the central nervous system. At the same time, the child becomes restless and may complain of a headache. Some children have sleep disturbances. Children with impaired nasal breathing begin to breathe through their mouths, and the cold air entering the respiratory tract easily leads to colds; such children get sick more often. And finally, nasal breathing disorder leads to a disturbance in the worldview. Children who do not breathe through their nose have a reduced quality of life. Paranasal sinuses Paranasal sinuses are limited air spaces of the facial skull, additional air reservoirs. In young children they are not sufficiently formed, so diseases such as sinusitis and sinusitis are extremely rare in children under the age of 1 year. At the same time, inflammatory diseases of the paranasal sinuses often bother children at an older age. It can be quite difficult to suspect that a child has inflammation of the paranasal sinuses, but you should pay attention to symptoms such as headache, fatigue, nasal congestion, and deterioration in school performance. Only a specialist can confirm the diagnosis, and the doctor often prescribes an X-ray examination. 33. Pharynx The pharynx in children is relatively large and wide. It concentrates large number lymphoid tissue. The largest lymphoid formations are called tonsils. Tonsils and lymphoid tissue play protective role in the body, forming the Waldeyer-Pirogov lymphoid ring (palatine, tubal, pharyngeal, lingual tonsils). The pharyngeal lymphoid ring protects the body from bacteria, viruses and performs other important functions. In young children, the tonsils are poorly developed, so diseases such as tonsillitis are rare in them, but colds, on the contrary, are extremely common. This is due to the relative vulnerability of the pharynx. Tonsils reach their maximum development by 4-5 years, and at this age children begin to suffer less from colds. These open into the nasopharynx important formations, like the Eustachian tubes connecting the middle ear (tympanic cavity) with the pharynx. In children, the mouths of these tubes are short, which often causes inflammation of the middle ear, or otitis, with the development of a nasopharyngeal infection. Ear infections occur through swallowing, sneezing, or simply from a runny nose. Long course otitis is associated specifically with inflammation of the Eustachian tubes. Prevention of middle ear inflammation in children is thorough treatment of any infection of the nose and pharynx. Larynx The larynx is a funnel-shaped structure next to the pharynx. When swallowing, it is covered by the epiglottis, which is like a lid that prevents food from entering the respiratory tract. The mucous membrane of the larynx is also richly supplied with blood vessels and lymphoid tissue. The opening in the larynx through which air passes is called the glottis. It is narrow, on the sides of the gap there are vocal cords - short, thin, so children's voices are high, ringing. Any irritation or inflammation can cause swelling of the vocal cords and subglottic space and lead to breathing problems. Young children are more susceptible to these conditions than others. Inflammatory process in the larynx is called laryngitis. In addition, if the baby has underdevelopment of the epiglottis or a violation of its innervation, he may choke and periodically experience noisy breathing, which is called stridogh. As the child grows and develops, these phenomena gradually disappear. . In some children, breathing from birth may be noisy, accompanied by snoring and wheezing, but not in sleep, as sometimes happens in adults, but during wakefulness. In case of restlessness and crying, these noise phenomena uncharacteristic for a child may intensify. This is the so-called congenital stridor of the respiratory tract, it is caused by congenital weakness of the cartilages of the nose, larynx and epiglottis. Although there is no discharge from the nose, at first the parents think that the child has a runny nose, however, the applied treatment does not give the desired result - the baby’s breathing is equally accompanied by various sounds. Pay attention to how the child breathes in his sleep: if he breathes calmly, and before crying he starts to “grunt” again, apparently, this is what we are talking about. Usually by two years, to the extent of strengthening cartilage tissue, stridor breathing disappears on its own, but until this time, in the case of acute respiratory diseases, the breathing of a child who has such structural features of the upper respiratory tract can significantly worsen. A child suffering from stridor should be observed by a pediatrician, consult an ENT doctor and a neurologist. 34. Bronchi The lower respiratory tract is represented mainly by the trachea and bronchial tree. The trachea is the largest breathing tube in the body. In children, it is wide, short, elastic, easily displaced and compressed by any pathological formation. The trachea is strengthened by cartilaginous formations - 14-16 cartilaginous half-rings, which serve as the frame for this tube. Inflammation of the mucous membrane of the trachea is called tracheitis. This disease is very common in children. Tracheitis can be diagnosed by a characteristic, very rough, low-pitched cough. Usually parents say that the child coughs “like a pipe” or “like a barrel.” Bronchi are the whole system airway tubes forming the bronchial tree. The branching system of the bronchial tree is complex; it has 21 orders of bronchi - from the widest, which are called “main bronchi,” to their smallest branches, which are called bronchioles. Bronchial branches are entangled with blood and lymphatic vessels. Each previous branch of the bronchial tree is wider than the next, so the entire bronchial system resembles a tree turned upside down. The bronchi in children are relatively narrow, elastic, soft, and easily displaceable. The mucous membrane of the bronchi is rich in blood vessels, relatively dry, since the secretory apparatus of the bronchi is underdeveloped in children, and the secretion produced by the bronchial glands is relatively viscous. Any inflammatory disease or irritation of the respiratory tract in young children can lead to a sharp narrowing of the lumen of the bronchi due to swelling, accumulation of mucus, compression and cause breathing problems. With age, the bronchi grow, their lumens become wider, the secretion produced by the bronchial glands becomes less viscous, and breathing disorders during various bronchopulmonary diseases are less common. Every parent should know that if signs of difficulty breathing occur in a child of any age, especially young children, urgent consultation with a doctor is necessary. The doctor will determine the cause of the breathing disorder and prescribe correct treatment. Self-medication is unacceptable, as it can lead to the most unpredictable consequences. Diseases of the bronchi are usually called bronchitis.