Features of the respiratory system in children. Anatomical and physiological features of the respiratory system in children

Providing the body with oxygen is one of the essential functions any living organism. The respiratory system of the child's body has its advantages, but there are also disadvantages.

Anatomical and physiological features of the newborn are not perfect. The respiratory organs are very thin and loose.

The lungs in children have fewer gaps than in adults. The respiratory system of a child is formed during the first 7 years and becomes the same as in an adult. After that, it only increases in size as the child grows.

The function of respiration is to enrich the cells of the body with oxygen.

Respiratory system human body consist of the nasal cavity, pharynx, larynx, trachea, bronchi and lungs. Air enters the nasopharynx through the nostrils. Here, with the help of mucus and a large number of glands, the air is moistened and warmed. The mucus of the nasopharynx cleans the air of dust, germs and other harmful substances.

Through the larynx and trachea, air enters the lungs. When you inhale, air enters the lungs, and with the help of the alveoli, air is exchanged. Oxygen enters pulmonary system while exhaling carbon dioxide is also removed.

The alveoli are closely adjacent to the cells of the capillaries, and when inhaled, oxygen easily passes into the pulmonary capillaries. From the capillaries, oxygenated blood enters the pulmonary veins and enters the left heart chamber. From there it is transferred to all organs of the human body.

Through the capillaries located in various bodies body, "exhaust" air with carbon dioxide enters the venous system. Further through the right heart valve blood with carbon dioxide enters the lungs. Well, then, as mentioned above, - exhale.

The air supply in the lungs is enough for 5-6 minutes. A child's respiratory system is much smaller than an adult's, so breathing occurs much more frequently. In a minute, a child can take up to 60 breaths.

To purify the air entering the body, it is necessary that it pass through the glands and mucous membranes located in the nose. Only here, with the help of mucus and leukocytes, the air is disinfected. When exhaling, all dust particles and microbes leave the body. Thus, the body's defense system is built. Therefore, it is very important to always breathe through the nose (especially in the street or in public places).

Features of the structure of the respiratory system in children

Anatomical and physiological features differ from the structure of the adult respiratory system. In children, they are characterized by:

narrow lumen;
short stroke length;
the presence of vascular vessels in the mucosa;
a delicate sheath of the lining tissues of the respiratory system;
loose tissues of the lymph.

The respiratory system is subject to greater penetration of microbes into the body. Because of this, children often suffer from respiratory diseases. With age, physiological features disappear. The system becomes more resistant to the environment in which the child's body is located.

In a child, it consists of respiratory tract and respiratory department. The latter is the lungs themselves. The respiratory tract, in turn, is divided into upper and lower.

Upper paths

The upper respiratory tract of a child has in its structure the nose, nasopharyngeal space and cavity, nasal canal and pharynx. The system of the upper pathways is still poorly developed, unable to reflect infectious penetrations and fight foci of diseases. It is because of poor development that the child is exposed to frequent diseases: SARS, acute respiratory infections, influenza.

The nasal passages are short and narrow. Even the smallest swelling can affect the quality of breathing through the upper respiratory tract. Such a structure in children younger age due to the features of the facial skeleton. In the same period of development of the child, the sinuses of the nose are already developed, but only two: the upper and middle. The lower sinus will form during the first 4 years of a baby's life.

The lining of the sinuses has a large number of blood vessels. Any damage to the mucosa, which is rich in blood vessels, can lead to injury. Up to 9 years of age, nosebleeds in a child are absent due to undeveloped cavernous tissue. If a baby has similar phenomena, then the child may have a pathology different nature. In infancy, the child develops only maxillary sinuses; the main sinus is still missing.

The frontal and ethmoid will have a familiar appearance only by 2 years of age. This structure of the sinuses of the baby's nose provides more complete cleansing and humidification of the inhaled air, and also explains the rarity of diseases such as sinusitis. In some cases, children may still develop chronic sinusitis and within a short period of time.

Nasolacrimal canal

The nasolacrimal canal is quite short and is very close to the eye.

Due to this structure, during inflammation and development lung diseases conjunctivitis quickly appears.

The pharynx of the child is also short, narrow and small. In the pharynx there is a lymphoid ring, in which the tonsils are located. The child has 6 of them. When examined by a doctor, a pharynx is often visible. This is the name given to the accumulation of various tonsils at the base of the pharynx.

The structure of the tonsils and the space around them is very loose, susceptible to "settlement" of infections. Because of this, infections easily enter the body, the child often suffers from respiratory diseases. They are often located on the tonsils, adenoids and other elements of the respiratory system located in the pharynx. The pharynx connects to the auditory canals.

Because of this structure, the infection can easily get into the child's hearing organs. With age, the channels increase in size, and infections practically do not penetrate. Due to frequent diseases in the pharynx, the child can be subjected to disorders of the nervous system, this may explain poor school performance. Because of this type of breathing, it is possible to “acquire” an adenoid face: the child does not have nasal breathing, the mouth is constantly open, and puffiness of the face is observed.

The epiglottis is also very small in a child early age. Incorrect positioning can result in "heavy" breathing that others can clearly hear. The epiglottis connects to the lower respiratory tract. During a meal, it closes the passage of food to the lungs. Performs a protective function.

lower paths

The lower respiratory tract consists of the larynx, trachea and bronchi, lungs and diaphragm. Their structure is also different. The whole system lower paths more developed.

At birth, the baby's larynx is in a position that is much higher than usual. It is very mobile, and over time the position changes.

Her position is not the same, it is different for each child. The larynx has the shape of a funnel, narrows towards the subglottic space, the lumen of the larynx is narrow. In a newborn, the diameter of the larynx is only 4 mm.

The width of the larynx increases extremely slowly and only by the age of 14 has a diameter of 10 mm. The vocal cords in children are short. It is this fact, in addition to the high location of the larynx, that explains the high timbre of the voice. By age 10 vocal cords lengthen, and the timbre changes.

thyroid cartilage

The thyroid cartilages have an obtuse angle. In boys, it becomes acute by adolescence, and you can already see the male larynx. The mucous membrane is tender and loose. A large amount of lymphoid tissue in the larynx swells easily with an infectious disease, and heavy breathing occurs.

Trachea

The trachea in a child's body is also located above the usual position of an adult. It is located at the level of the 3rd cervical vertebra; as the body grows, the trachea descends several vertebrae lower. The trachea has a funnel-shaped structure consisting of 16 rings. With age, the rings fuse, and a dense cylindrical shape of the trachea is formed.

The trachea is relatively narrow. It has a large number of muscles, due to which the lumen of the trachea changes when breathing or coughing. The mucous membrane of the trachea is tender and dry. Newborns under 2 years of age may experience snoring breathing. This is due to the softness of the trachea. With the development of the whole organism and individual organs of the system, it becomes denser, the snoring syndrome disappears.

Bronchi

The tracheae are fused with the bronchial tree. It consists of a right and a left side. The dimensions of the bronchi are different. The right side is much wider and shorter, it is the main one. Often right part is a continuation of the trachea. It is in this part that foreign objects are found that the child can inhale.

The left side of the bronchi is narrow and long. The number of branches in the bronchi does not change with age, and the distribution of air during breathing remains constant. The bronchi have several layers of epithelium, the ciliated function develops in the postnatal period.

On the epithelium is mucus, which has a cleansing function. Due to the large number of cilia, mucus can move. Its speed is about 1 cm per minute. The cartilages in the bronchi are also very mobile and easily change position. When irritated, asthma can develop.

Due to poor development of elastic muscle tissue and non-coated nerve fibers skull force of cough is not sufficiently developed. With age coughing impulse gains more power. This contributes to the activity of the bronchi and the development of the ciliated function of the epithelium.

With a respiratory disease, the amount of mucus in the bronchi also increases. With a slight increase in the lumen of the bronchi is reduced several times.

This leads to breathing difficulties. Coughing does not help to get rid of the infection in the bronchi, and the lung tissue succumbs to the disease. The tissue easily swells and clogs the gaps.

Lungs

The lungs in a child's body have a similar structure with lungs of an adult person. They are also divided into segments: 10 segments are distinguished in the right lung, only 9 in the left. There are 3 lobes in the child's right lung (while only 2 in the left lung).

The segments are easily separated from each other by grooves and connective tissue. A feature of the structure of the lungs of a child's body is the end of the lungs in the form of a sac of alveoli. They resemble the lacy edges of a knitted napkin. With age, the sacs form new alveoli, the acinus has clusters of standard alveoli.

A baby born at term has about 24 million alveoli. For 3 months of life, they become several times more. But even this number of alveoli in newborns is 3 times reduced. Inner surface lined with surfactant.

It is this that allows the alveoli not to stick together and always have round shape. It also performs a protective function against various microbes, viruses. The substance is formed in the last months prenatal development. Surfactant deficiency can cause respiratory syndrome.

The baby's alveoli increase in size. In addition, the number of alveoli in the lungs is also increasing. In the first year of life, the diameter is 0.05 mm, and by the age of 5 it increases almost 3 times. The tissue between the alveoli contains many vessels, fiber and little connective tissue.

Therefore, the lungs of young children are less airy. With age, this "defect" disappears. The density of the alveoli allows respiratory inflammation to occur for no apparent reason.

The pleura in young children is thick and loose, has many folds, villi, outgrowths. It is in these places that foci of pulmonary infections are created.

Mediastinum

It is quite large in comparison with an older organism. The main part of it is the root of the lung. The organ consists of large bronchi, vessels and lymph nodes. Due to the large size of the lymph nodes, children are more likely to get sick (but the lymphatic system is not underdeveloped or bad).

The diaphragm in a child is an important part of breathing. It provides depth of inspiration. With its poor development, the baby can observe shallow breathing, which can also be caused by stomach cramps, gases in the intestines and other gastrointestinal disorders. You can determine the correct development of the diaphragm using palpation. chest.

Features of the functioning of the respiratory system in children

The respiration of the body is necessary to supply the organs with oxygen. It is conditionally divided into external and internal. External respiration begins with the entry of air into the upper tracts and ends with gas exchange in the alveoli. The effectiveness of external respiration is due to 3 factors:

ventilation of the alveoli;
the intensity of the work of capillaries;
diffusion of gases.

The ventilation of the alveoli depends not only on the work of the lungs, but also on the nerve signals supplied from the central nervous system. Violation leads to an increase in the load on the respiratory organs and their efficiency. Diffusion and the intensity of capillary operation depend on the pressure difference during gas exchange and the concentration of particles.

Internal respiration depends on the metabolism that occurs in the organs and cells of the child's body.

The functioning of the respiratory system in young children is accompanied by the following features:

shallow breathing;
shortness of breath;
arrhythmia;
respiratory failure.

The peculiarity of the baby's respiratory system is quite satisfied with the body's oxygen needs. From the first days of life, the system develops rapidly and adapts to the new environment.

The first need for oxygen in a newborn is due to a sharp decrease in the level of oxygen in the body at the time of clamping the umbilical cord. It is through this organ that the fetus in the womb receives oxygen. In addition, the body enters a different environment: dry and cold.

Signals about the lack of oxygen enter the central nervous system, and then are transmitted to the respiratory system. At the time of the birth of a child, the respiratory tract is cleared of fluids: part of the fluid is absorbed into the tissues and lymph of the baby.

In the first year, respiratory arrhythmia is very often observed in children. Over time, it should pass, and breathing will enter its usual rhythm.

Shallow breathing is due to the weak development of the diaphragm and structural features of the chest. The respiratory rate in a newborn is 40-60 breaths per minute. With age, the respiratory rate decreases to 20 breaths per minute. This norm corresponds to 10 years of age.

The number of breaths in an adult should not exceed 21 breaths per minute. The greater frequency of inspiration is related to its depth. The baby cannot take a deep breath from the small volume of the lungs and undeveloped muscles.

From the first years of life, the percussion tone of the baby should be clear with a slight shade. Normal breath sounds are different for every age. In infancy, breathing seems to be weakened. In fact, these are the features of the baby's shallow breathing. From the age of two, breathing is heard more clearly. Children school age and older have breathing like adults.

The lung capacity of a child is much lower than that of an adult. Therefore, the absolute value of respiration volume is much lower. But in terms of body weight, this figure is much higher. With age, the indicators change. Gas exchange in children is much more intense due to the presence of a large amount of pulmonary vascularization. This process allows you to quickly deliver oxygen to the organs and tissues of the body and remove carbon dioxide.

Such methods and signs will help to distinguish the functional features of the child's breathing.

Poll

A survey of a child or mother during a visit to a doctor will identify possible complications and features of the development of the respiratory system. Here it is necessary to pay attention to the presence of discharge from the nose, breathing, the presence of a cough. For external examination, different methods to detect pathologies and complications.

cyanosis and shortness of breath

Cyanosis is expressed by blue in some areas of the child's skin. It can be nasolabial folds, fingers or toes. It can manifest itself with certain manipulations or be permanent.

Shortness of breath occurs with the participation of the muscles of the child during breathing or in the presence of bronchopulmonary diseases.

Cough

The voice of the child can determine the presence of the disease. Husky and hoarse voice- a clear witness to an infectious disease. A nasal voice indicates the presence of a runny nose. A rare and periodic bright cry of a baby may indicate periodic pain in the abdomen or otitis media. A monotonous cry may indicate damage to the nervous system.

With the help of a cough, you can assess the state of health of the baby. Even if there is no cough, it can be artificially induced and the condition of a small patient can be determined. For example dry or moist cough indicates the presence of a respiratory disease. A cough that ends in vomiting can be seen in whooping cough.

If you suspect any diseases, it is best to undergo an examination using a modern medical equipment. This will allow you to accurately determine the nature of the disease or refute it.

Finally

The respiratory system of a child at an early age is poorly developed. Many organs are still underdeveloped, have small size or not fully developed. This contributes to frequent illnesses. The structure of the respiratory system is very similar to that of an adult.

The structural features of the respiratory organs of the upper tracts make it possible to better moisten and purify the air entering the child's body. Due to the absence of some sinuses, infections easily penetrate the baby's body and spread there. The lower respiratory tract is better formed and has a structure that is similar to that of an adult organism.

The functioning of the respiratory organs is due to the frequency of inhalations and exhalations, the lack of rhythmic breathing, structural features and development of the respiratory organs, gas exchange, metabolism and other factors. Knowledge distinctive features help parents worry less about their baby, identify possible diseases still at an early stage.

The respiratory organs are in close connection with the circulatory system. They enrich the blood with oxygen, which is necessary for oxidative processes occurring in all tissues.

Tissue respiration, that is, the use of oxygen directly from the blood, occurs even in the prenatal period, along with the development of the fetus, and external respiration, i.e., the exchange of gases in the lungs, begins in the newborn after cutting the umbilical cord.

What is the mechanism of respiration?

With each breath, the chest expands. The air pressure in it decreases and, according to the laws of physics, the outside air enters the lungs, filling the rarefied space formed here. When you exhale, the chest shrinks and the air from the lungs rushes out. The chest is set in motion due to the work of the intercostal muscles and the diaphragm (abdominal obstruction).

The act of breathing is controlled by the center of breathing. It is located in the medulla oblongata. Carbonic acid accumulated in the blood serves as an irritant of the respiratory center. Inhalation is replaced by exhalation reflexively (unconsciously). But the higher department, the cerebral cortex, also takes part in the regulation of respiration; by force of will it is possible to a short time hold your breath or make it faster, deeper.

The so-called airways, that is, the nasal cavities, larynx, bronchi, are relatively narrow in a child. The mucous membrane is tender. It has a dense network of the thinnest vessels (capillaries), easily inflames, swells; this leads to the exclusion of breathing through the nose.

Meanwhile, nasal breathing is very important. It warms, moisturizes and cleans (which helps to preserve tooth enamel) the air passing into the lungs, irritates the nerve endings that affect the stretching of the bronchi and pulmonary vesicles.

Increased metabolism and, in connection with this, an increased need for oxygen and active motor activity lead to an increase in the vital capacity of the lungs (the amount of air that can be exhaled after a maximum breath).

In a three-year-old child, the vital capacity of the lungs is close to 500 cubic cm; by the age of 7 it doubles, by 10 it triples, and by 13 it quadruples.

Due to the fact that the volume of air in the airways in children is less than in adults, and the need for oxidative processes is great, the child has to breathe more often.

Quantity respiratory movements per minute for a newborn is 45-40, for a one-year-old - 30, for a six-year-old - 20, for a ten-year-old - 18. In physically trained people, the respiratory rate at rest is less. This is because they have deeper breathing. and the oxygen utilization rate is higher.

Hygiene and airway training

It is necessary to pay serious attention to the respiratory hygiene of children, in particular to hardening and accustoming to nasal breathing.

In children, it occurs at the 3-4th week of gestation. The respiratory organs are formed from the rudiments of the anterior intestine 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 blood and nervous system lungs. By birth, the vessels of the lungs are already formed, the airways are quite developed, but filled with fluid, the secret of the cells of the respiratory tract. After birth, with a cry and the first breath of the child, this liquid is absorbed and coughed up.

The surfactant system is of particular importance. Surfactant - a surfactant that is synthesized at the end of pregnancy, helps to straighten the lungs during the first breath. With the onset of breathing, immediately in the nose, the inhaled air is cleaned of dust, microbial agents due to biologically active substances, mucus, bactericidal substances, secretory immunoglobulin A.

The respiratory tract of a child adapts with age 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, the lower nasal passage is not yet formed. The cartilaginous skeleton of the nose is very soft. The nasal mucosa is richly vascularized with blood and lymphatic vessels. By about four years, 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 old. It is almost impossible for them to breathe through the mouth, since the oral cavity is occupied by a relatively large tongue, pushing the epiglottis backwards. Therefore, in acute rhinitis, when breathing through the nose is sharply difficult, the pathological process quickly descends into the bronchi and lungs.

Development paranasal sinuses nose also occurs after a year, so in children of the first year of life, their inflammatory changes are rare. So than less baby, the more adapted his nose is to warming, moistening and purifying the air.

The pharynx of a newborn baby is small and narrow. The pharyngeal ring of the tonsils is under development. 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, the 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 adverse conditions (infection of the ENT organs), their hypertrophy may appear.

The physiological role of the tonsils and the entire pharyngeal ring is the filtration and sedimentation of microorganisms from the environment. Prolonged contact with a microbial agent, sudden cooling of the child protective function tonsils weakens, they become infected, their acute or chronic inflammation develops with a corresponding clinical picture.

Nasopharyngeal tonsil enlargement is most often associated with chronic inflammation, against the background of which there is a violation of breathing, allergization and intoxication of the body. Hypertrophy of the palatine tonsils leads to violations of the neurological status of children, they become inattentive, do not study well at school. With hypertrophy of the tonsils in children, a pseudo-compensatory malocclusion is formed.

Most frequent illnesses upper respiratory tract in children are acute rhinitis and tonsillitis.

The larynx of 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. Gender differences In the structure of the larynx appear to puberty. In boys, the larynx in place of the thyroid cartilage is sharpened, 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.

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

The trachea is already formed by the birth of the child. The upper edge of the ce 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, 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 overtakes the growth of the trachea.

During physiological respiration the lumen of the trachea changes, during coughing it decreases by approximately 1/3 of its transverse and longitudinal size. The mucous membrane of the trachea contains many secreting glands. Their secret covers the surface of the trachea with a layer 5 microns thick, the speed of mucus movement from the inside outward (10-15 mm / min) is provided by the ciliated epithelium.

In children, diseases of the trachea such as tracheitis are often noted, in combination with damage to the larynx (laryngotracheitis) or bronchi (tracheobronchitis).

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

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

In a newborn child, the mass of the lungs is small and is approximately 50-60 g, this is 1/50 of its mass. In the future, the mass of the lungs increases by 20 times. In newborns, the lung tissue is well vascularized, it has a lot of loose connective tissue, and the elastic tissue of the lungs is less developed. Therefore, in children with lung diseases, emphysema is often noted. The acinus, 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 the alveoli of the lungs;

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 the birth of a child, the upper lobe of the left lung is worse developed. By 2 years, the sizes of individual lobes correspond to each other, as in adults.

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

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 - the 6th segment). It is in it that conditions are created for poor drainage in the supine position in children. infancy. Another place of pure localization of inflammation in children - 2nd segment upper lobe and basal-posterior (10th) segment of the lower lobe. Here so-called paravertebral pneumonias develop. Often the middle lobe is also affected. Some segments of the lung: mid-lateral (4th) and mid-lower (5th) - are located in the region of the bronchopulmonary lymph nodes. Therefore, during inflammation of the latter, 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 time of birth, the umbilical circulation stops. The partial pressure of oxygen (pO 2) decreases, the pressure of carbon dioxide increases (pCO 2), and the acidity of the blood (pH) decreases. Impulse from peripheral receptors carotid artery and aorta to the respiratory center of the CNS. Along with this, impulses from skin receptors go to the respiratory center, as the conditions for the child's stay in the environment. It enters colder air with less moisture. These influences also irritate the respiratory center, and the child takes the 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 have apnea (cessation of breathing).

Oxygen reserves in the body are limited, they are enough for 5-6 minutes. Therefore, a person must maintain this reserve with constant breathing. From a functional point of view, two parts of the respiratory system are distinguished: conductive (bronchi, bronchioles, alveoli) and respiratory (acini with adducting 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 mm Hg. Art., which ensures the passage of oxygen from the alveoli through the alveolar-capillary membrane into the blood. At this time, carbon dioxide, which is also in the blood under high pressure, passes from the blood at this time. Children have significant differences in external respiration compared with adults due to the continued development of 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 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) lung volume; 3) mechanics of breathing; 4) pulmonary gas exchange; 5) gas composition arterial blood. The calculation and evaluation of these indicators is carried out in order to determine the functional state of the respiratory system and reserve capacity in children of different ages.

Respiratory examination

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

It is necessary to find out the timing of the onset of the disease, the main complaints and symptoms, whether the child took any drugs and how they affected the dynamics clinical symptoms what complaints to date. This information should be obtained from the mother or 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 a cough, the nature of which is used to judge 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, swelling of the wings of the nose are visible. In older children, one can notice retraction of the compliant places of the chest, retraction of the abdomen, a forced position (sitting with support with hands - with bronchial asthma).

The doctor examines the nose, mouth, pharynx and tonsils of the child, differentiates the existing cough. Croup in a child is accompanied by stenosis of the larynx. There are true (diphtheria) croup, when the narrowing of the larynx occurs due to diphtheria films, and false croup (subglottic laryngitis), which occurs due to spasm and edema against the background of acute inflammatory disease larynx. True croup develops gradually, in days, false croup - unexpectedly, more often at night. The voice with croup may reach aphonia, with sharp breaks of sonorous notes.

Cough with whooping cough in the form of a paroxysm (paroxysmal) with reprises (long high breath) is accompanied by reddening of the face and vomiting.

A bitonic cough (rough basic tone and musical second tone) is noted with an increase in bifurcation lymph nodes, tumors in this place. A painful dry cough is observed with pharyngitis and nasopharyngitis.

It is important to know the dynamics of cough changes, whether the cough bothered you before, what happened to the child and how the process ended in the lungs, 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 character. Pay attention to increased cyanosis, especially around the mouth and eyes, when crying, physical activity of the child. In children under 2-3 months of age, on examination, there may be foamy discharge from the mouth.

Pay attention to the shape of the chest and the type of breathing. abdominal type breath remains at boys and in an adult state. In girls, from 5-6 years old appears chest type breathing.

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

According to the frequency of breathing, its relationship with the pulse, the presence or absence of respiratory failure. By the nature of shortness of breath, one or another lesion of the respiratory system is judged. Shortness of breath 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, pharyngeal abscess, etc.). When a child inhales, there is a 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, almost does not participate in breathing, and the stomach, on the contrary, actively participates in the act of breathing. In this case, the exhalation is longer than the 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.

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

Shortness of breath is often observed in newborns with respiratory distress syndrome.

Palpation of the chest in a child is carried out with both hands to determine its soreness, resistance (elasticity), elasticity. Also measure the thickness skin fold on symmetrical areas of the chest to determine inflammation on one side. On the affected side, there is a thickening of the skin fold.

Next, move on to percussion of the chest. Normally, in children of all ages, both sides receive the same percussion. With various lesions of the lungs, the percussion sound changes (dull, boxy, etc.). Topographic percussion is also carried out. There are age standards for the location of the lungs, which can change with pathology.

After comparative and topographic percussion, auscultation is performed. Normally, in children up to 3-6 months, they listen to somewhat weakened breathing, from 6 months to 5-7 years - puerile breathing, and in children over 10-12 years old it is more often transitional - between puerile and vesicular.

With pathology of the lungs, the nature of breathing often changes. Against this background, dry and wet rales, pleural friction noise can be heard. To determine the compaction (infiltration) in the lungs, the method of assessing bronchophony is often used when voice conduction is heard under symmetrical sections of the lungs. With compaction of the lung on the side of the lesion, increased bronchophony is heard. With caverns, bronchiectasis, there may also be an increase in bronchophony. The weakening of bronchophony is noted in the presence of fluid in the pleural cavity (effusion pleurisy, hydrothorax, hemothorax) and (pneumothorax).

Instrumental Research

In lung diseases, the most common study is x-ray. In this case, x-rays or fluoroscopy are performed. Each of these studies has its own indications. At X-ray examination lungs pay attention to the transparency of the lung tissue, the appearance of various blackouts.

To special studies include bronchography - a diagnostic method based on the introduction of a contrast agent into the bronchi.

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

Of the other methods used computed tomography, which allows you to examine in detail the state of the mediastinal organs, the root of the lungs, to see changes in the bronchi and bronchiectasis. When using nuclear magnetic resonance, a detailed study of the tissues of the trachea, large bronchi is carried out, you can see the vessels, their relationship with the respiratory tract.

An effective diagnostic method is endoscopy, including anterior and posterior rhinoscopy (examination of the nose and its passages) using the nasal and nasopharyngeal mirrors. The study of the lower part of the pharynx is carried out using special spatulas (direct laryngoscopy), the larynx - 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, drain these formations (suction of mucus) and biopsy them, and administer drugs.

There are also methods for studying external respiration based on a graphical recording of respiratory cycles. According to these records, the function of external respiration in children older than 5 years is judged. Then pneumotachometry is performed with a special apparatus that allows determining the state of bronchial conduction. The state of ventilation function in sick children can be determined using the method of peak flowmetry.

From laboratory tests, the method of studying gases (O 2 and CO 2) in the patient's capillary blood on the micro-Astrup apparatus is used.

Oxyhemography is performed using a photoelectric measurement of light absorption through the pinna.

Of the stress tests, a test with a breath-hold on inspiration (Streni test), a test with physical activity. When squatting (20-30 times) in healthy children, there is no decrease in blood oxygen saturation. A test with oxygen exhalation is done when breathing is switched on for oxygen. In this case, there is an increase in the saturation of the exhaled air by 2-4% within 2-3 minutes.

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

About 70% of the diseases characteristic of childhood are due to a violation normal operation respiratory organs. They are involved in passing air through the lungs, while preventing them from entering pathogenic microorganisms and further development inflammatory process. At the slightest failure in the full functioning of the respiratory organs, the entire body suffers.

Photo: Respiratory organs

Features of the respiratory system in childhood

Respiratory diseases in children occur with some features. This is due to a number of factors:

narrowness of the nasal passages and glottis;
insufficient depth and increased respiratory rate;
low air and increased density lungs;
underdevelopment respiratory muscles;
unstable respiratory rhythm;
tenderness of the nasal mucosa (rich in blood vessels and swells easily).

Photo: Respiratory muscles

Mature respiratory system becomes no earlier than 14 years. Up to this point, pathologies related to it should be given increased attention. Detection of diseases of the respiratory system should occur in a timely manner, which increases the chances of a speedy cure, bypassing complications.

Causes of diseases

The child's respiratory organs are often exposed. Often pathological processes develop under the influence of activation of staphylococci and streptococci. Allergies often lead to respiratory problems.

Among the disposing factors are not only the anatomical features of the respiratory system in childhood, but also unfavorable external environment, hypovitaminosis. Modern children with noticeable regularity do not follow the daily routine and eat improperly, which affects the body's defenses and subsequently leads to diseases. The lack of hardening procedures can aggravate the situation.

Photo: Activation of staphylococci is the cause of the disease

Symptoms

Despite the existence of signs characteristic of each individual disease of the respiratory system of a child, doctors distinguish common ones:

(mandatory symptom, a kind of protective reaction of the body);
dyspnea(indicates a lack of oxygen);
sputum(special mucus produced in response to the presence of irritants);
nasal discharge(can be different color and consistency)
labored breathing;
temperature increase(this also includes general intoxication of the body, which is a set of biological reactions of the body to infection).

Photo: Phlegm

Diseases of the respiratory system are divided into two groups. The first affect the upper respiratory tract (URT), the second - the lower sections (LRT). In general, it is not difficult to determine the onset of one of the respiratory diseases in a child, especially if a doctor takes up the work. With the help of a special device, the doctor will listen to the child and perform an examination. If the clinical picture is blurred, a detailed examination will be required.

Photo: Examination of a child by a doctor

Diseases of the upper respiratory tract

Viruses and bacteria can lead to pathologies. It is known that presented group of diseases is one of the common causes appeals of the child's parents to the pediatrician.

According to statistical data, a child of preschool and primary school age can suffer from 6 to 10 episodes of violations of the VRT per year.

Inflammation of the nasal mucosa, which occurs against the background viral infection . The impetus for the development of rhinitis can be a banal hypothermia, as a result defensive forces organism.

Photo: Rhinitis

Acute rhinitis can be a symptom of an acute infectious disease or manifest itself as an independent pathology.

Photo: Lower respiratory tract

As independent disease tracheitis is extremely rare.

Photo: Breathing exercises

Can trouble be prevented?

Any respiratory disease can be prevented. To this end, it is necessary to temper the child's body, regularly take walks with him on fresh air, always dress for the weather. It is very important to avoid hypothermia and wet feet. In the off-season, the health of the child should be maintained with vitamin complexes.

At the first sign of discomfort, you should contact a specialist.

Photo: At the doctor's appointment

TO THE PRACTICE

III year specialty "Pediatrics"

Discipline:"Propaedeutics of childhood diseases with courses healthy child and general child care

Anatomical and physiological features of the respiratory system

in children and adolescents, association with pathology

Lesson duration ___ hours

Class type- practical lesson.

Purpose of the lesson:

To study the anatomical and physiological features and principles of the functioning of the respiratory system in children and adolescents.

The main questions of the topic:

1. Organogenesis of the bronchial tree and lungs for understanding airway abnormalities

2. Anatomical features of the structure of the upper respiratory tract

3. Anatomical and physiological features of the lymphopharyngeal ring

4. Anatomical features of the structure of the middle respiratory tract

5. Anatomical features of the structure of the lung tissue

6. Stages of development of lung tissue

7. Segmental structure of the lungs and its influence on the localization of the pulmonary inflammatory process in children

8. Age features stages of respiration in children: external respiration, oxygen transport from lungs to tissues; tissue respiration, transport of carbon dioxide from tissues to the lungs.

9. Features of gas diffusion through the alveolo-capillary membrane and ventilation-perfusion ratios in children. Blood gases in children

Questions for independent study by students:

1. Mechanism of the first breath

2. Surfactant system, mechanisms of formation and biological significance

3. Examination of the patient (objectively and subjectively) with subsequent assessment of the examination data in comparison with the norm.

Lesson equipment: tables, diagrams, case histories, an indicative map of action, an audio archive with records of respiratory sounds.

METHODOLOGICAL INSTRUCTIONS

Respiratory development in children

By the end of the 3rd - at the beginning of the 4th week embryonic development there is a protrusion of the wall of the anterior intestine, from which the larynx, trachea, bronchi and lungs are formed. This protrusion grows rapidly; at the caudal end, a flask-shaped expansion appears, which on the 4th week is divided into the right and left parts (the future right and left lungs). Each part is further divided into smaller branches (future shares). The resulting protrusions grow into the surrounding mesenchyme, continuing to divide and forming again spherical extensions at their ends - the rudiments of the bronchi of an increasingly small caliber. On the 6th week lobar bronchi are formed, on the 8-10th week - segmental bronchi. From the 16th week, respiratory bronchioles begin to form. Thus, by the 16th week, mainly the bronchial tree is formed. This is the so-called glandular stage of lung development.

From the 16th week, the formation of a lumen in the bronchi begins (recanalization stage), and from the 24th week, the formation of future acini (alveolar stage). The formation of the cartilaginous framework of the trachea and bronchi begins from the 10th week. From the 13th week, glands begin to form in the bronchi, which contributes to the formation of a lumen. Blood vessels form from the mesenchyme at week 20, and motor neurons from week 15. Particularly fast vascularization of the lungs occurs on the 26th - 28th week. Lymphatic vessels are formed on the 9-10th week, first in the region of the lung root. By birth, they are already fully formed.

The formation of acini, which began from the 24th week, continues in the postnatal period.

By birth, the airways (larynx, trachea, bronchi, and acini) are filled with fluid, which is a secretion product of airway cells. It contains a small amount of protein and has a low viscosity, which facilitates its rapid absorption immediately after birth from the moment breathing is established.

Surfactant, the layer of which (0.1-0.3 microns) covers the alveoli, begins to be synthesized at the end of fetal development. Methyl- and phosphocholine transferase are involved in the synthesis of surfactant. Methyltransferase begins to form from the 22nd - 24th week of intrauterine development, and its activity progressively increases towards birth. Phosphocholine transferase usually matures only by the 35th week of gestation. A deficiency in the surfactant system underlies respiratory distress syndrome, which is more commonly seen in preterm infants. Distress syndrome is clinically manifested by severe respiratory failure.

The above information on embryogenesis suggests that congenital tracheal stenosis and lung agenesis are the result of a developmental disorder at a very early stages embryogenesis. Congenital pulmonary cysts are also the result of a malformation of the bronchi and the accumulation of secretions in the alveoli.

The part of the foregut from which the lungs originate later turns into the esophagus. In case of violation right process embryogenesis remains a message between the primary intestinal tube (esophagus) and the grooved protrusion (trachea) - esophageal-trecheal fistulas. Although this pathology in newborns is quite rare, however, if it is present, their fate depends on how soon the diagnosis is established and how quickly the necessary health care. A newborn with such a developmental defect in the first hours looks quite normal and breathes freely. However, at the first attempt to feed, due to the ingress of milk from the esophagus into the trachea, asphyxia occurs - the child turns blue, a large number of wheezing is heard in the lungs, and an infection quickly forms. Treatment of such a malformation is only operational and should be applied immediately after the diagnosis is established. A delay in treatment causes severe, sometimes irreversible, organic changes in the lung tissue due to the constant ingestion of food and gastric contents into the trachea.

It is customary to distinguish upper(nose, throat) medium(larynx, trachea, lobar, segmental bronchi) and lower(bronchioles and alveoli) airways. Knowledge of structure and function various departments of the respiratory system is important for understanding the characteristics of respiratory pathology in children.

upper respiratory tract. The nose of a newborn is relatively small, its cavities are underdeveloped, the nasal passages are narrow (up to 1 mm). The lower nasal passage is absent. The cartilages of the nose are very soft. The mucous membrane of the nose is delicate, rich in blood and lymphatic vessels. By the age of 4, the lower nasal passage is formed. As they increase in size facial bones(upper jaw) and teeth erupt, the length and width of the nasal passages increase.

In newborns, the cavernous (cavernous) part of the submucosal tissue of the nose is underdeveloped, which develops only by 8-9 years. This explains the relative rarity of nosebleeds in children of the first year.

Due to the narrowness of the nasal passages and the abundant blood supply to the mucous membrane, the appearance of even a slight inflammation of the nasal mucosa causes difficulty in breathing through the nose in young children. Breathing through the mouth in children of the first six months of life is almost impossible, since a large tongue pushes the epiglottis backwards.

Although the accessory (adnexal) sinuses begin to form in the prenatal period, they are not sufficiently developed by birth (Table 1).

Table 1. Development of the paranasal sinuses (sinuses) of the nose

These features explain the rarity of diseases such as sinusitis, frontal sinusitis, ethmoiditis, polysinusitis (a disease of all sinuses) in early childhood.

When breathing through the nose, air passes with greater resistance than when breathing through the mouth, therefore, during nasal breathing, the work of the respiratory muscles increases and breathing becomes deeper. Atmospheric air passing through the nose is warmed, humidified and purified. The warming of the air is the greater, the lower the outside temperature. So, for example, the air temperature when passing through the nose at the level of the larynx is only 2 - 3% lower than body temperature. In the nose, the inhaled air is purified, and in the nasal cavity are captured foreign bodies larger than 5 - 6 microns in diameter (smaller particles penetrate into the underlying sections). 0.5 - 1 l of mucus per day is released into the nasal cavity, which moves in the posterior two-thirds of the nasal cavity at a speed of 8-10 mm / min, and in the anterior third - 1-2 mm / min. Every 10 minutes a new layer of mucus passes, which contains bactericidal substances, secretory immunoglobulin A.

The pharynx of a newborn is narrow and small. The lymphopharyngeal ring is poorly developed. Both palatine tonsils normally in newborns do not go out from behind the arches of the soft palate into the pharyngeal cavity. After a year of life, hyperplasia of the lymphoid tissue is observed, and the tonsils come out from behind the anterior arches. The crypts in the tonsils are poorly developed. Therefore, although there are tonsillitis in children under one year old, they are less common than in older children. By the age of 4-10 years, the tonsils are already well developed and their hypertrophy can easily appear. The tonsils are similar in structure and function to the lymph nodes.

The tonsils are, as it were, a filter for microbes, but with frequent inflammatory processes, a focus of chronic infection can form in them. Tonsils gradually increase, hypertrophy - develops chronic tonsillitis, which can proceed with general intoxication and cause microbial sensitization of the body.

Nasopharyngeal tonsils can increase in size - these are the so-called adenoid vegetations . They disrupt normal nasal breathing, and also, being a significant receptor field, can cause allergization, intoxication of the body, etc. Children with adenoids are inattentive, which affects their studies at school. In addition, adenoids contribute to the formation of malocclusion.

Among the lesions of the upper respiratory tract in children, rhinitis and tonsillitis are most often observed.

middle and lower respiratory tract. The larynx for the birth of a child has a funnel-shaped shape, its cartilages are tender and pliable. The glottis is narrow and located high (at the level of the IV cervical vertebra), and in adults - at the level of the VII cervical vertebra. The cross-sectional area of the airway under the vocal cords is on average 25 mm 2 , and the length of the vocal cords is 4-4.5 mm. The mucous membrane is tender, rich in blood and lymphatic vessels. Elastic tissue is developed_poorly.

Up to 3 years, the shape of the larynx is the same in boys and girls. After 3 years, the angle of connection of the thyroid plates in boys becomes sharper, and this becomes especially noticeable by the age of 7; by the age of 10, in boys, the larynx becomes similar to the larynx of an adult male.

The glottis remains still narrow until 6-7 years of age. True vocal cords in young children are shorter than in older ones (this is why they have a high voice); From the age of 12, the vocal cords in boys become longer than in girls. The peculiarity of the structure of the larynx in young children explains the frequency of its defeat (laryngitis), and often they are accompanied by difficulty breathing - croup.

The trachea is almost completely formed by the birth of the child. It has a funnel shape. Its upper edge is located at the level of the IV cervical vertebra (in an adult at level VII). The bifurcation of the trachea lies higher than in an adult. It can be tentatively defined as the intersection of lines drawn from the spina scapulae to the spine. The mucous membrane of the trachea is delicate and rich in blood vessels. The elastic tissue is poorly developed, and its cartilaginous framework is soft and easily narrows the lumen. With age, the trachea increases both in length and in transverse size (Table 2).

Table 2.

Similar information.