Termination of long-term mechanical ventilation - artificial ventilation in intensive care. Technique for artificial ventilation: description, rules, sequence of actions and algorithm for performing mechanical ventilation Artificial ventilation in intensive care

According to the ABC rule, the first stage of revitalization is the restoration of conductivity respiratory tract at the victim.

After the absence of breathing has been established, the victim is placed on a rigid base and the cervical spine is extended or the lower jaw is brought forward to eliminate the retraction of the root of the tongue. The oral cavity and pharynx must be freed from mucus, vomit, etc., if present. After this they begin artificial ventilation(ventilator).

There are two main ways of performing mechanical ventilation: external method and the method using blowing air into the lungs victim through the upper respiratory tract.

The external method involves rhythmic compression chest, which leads to its passive filling with air. Currently, external mechanical ventilation is not carried out, since adequate oxygen saturation of the blood, which is necessary to relieve signs of acute respiratory failure, does not occur when using it.

Air is blown into the lungs using the " mouth to mouth" or " mouth to nose". The person providing assistance blows air into the victim’s lungs through his mouth or nose. The amount of oxygen in the inhaled air is about 16%, which is quite enough to support the life of the victim.

The most effective method is “mouth to mouth”, but this method is associated with high risk infection. To avoid this, air should be injected through a special S-shaped air duct, if one is available. If it is not available, you can use a piece of gauze folded in 2 layers, but no more. Gauze can be replaced with another more or less clean material, for example, a handkerchief.

After completing the entire procedure, the person performing mechanical ventilation should cough well and rinse his mouth with any type of antiseptic or at least with water.

Technique for performing mechanical ventilation using the mouth-to-mouth method

• Place your left hand under the victim’s neck and back of the head, and your right hand on his forehead, so as to slightly tilt the victim’s head back, and with your fingers right hand hold his nose;
• Tightly cover the mouth of the victim with your mouth and exhale;
• The effectiveness of mechanical ventilation is controlled by an increase in the volume of the chest, which should straighten out at the time of inhalation of air into the victim;
• After the victim's chest has expanded, the assisting person turns his head to the side and the patient passively exhales.

Inhale air into the lungs of the victim should be at a frequency of 10-12 breaths per 1 minute, which corresponds to physiological norm, while the volume of exhaled air should be approximately half the normal volume.

If the resuscitator is resuscitating alone, then the ratio of the frequency of chest compressions of the victim to the rate of ventilation should be 15:2. The pulse is checked every four cycles of ventilation, and after every 2-3 minutes. A high frequency of inhalations-exhalations should be avoided in the mode of the maximum volume of inhaled air, since in this case problems will already arise for the resuscitator, which threatens him with respiratory alkalosis with a short-term loss of consciousness.

The mouth-to-nose method is resorted to if it is not possible to use the mouth-to-mouth method, for example, with maxillofacial injuries. A feature of the "mouth to nose" method is that it is much more difficult to carry out due to the anatomical features of the structure of the human respiratory system.

Mouth-to-nose ventilation technique

• Put your right hand on the forehead of the victim and tilt his head back;
• With your left hand, lift the lower jaw of the victim up, closing his mouth;
• Cover the victim's nose with your lips and exhale.

When performing mechanical ventilation in children, their nose and mouth are simultaneously captured by the lips, while the respiratory rate should be 18-20 per minute with a corresponding decrease in respiratory volume.

Typical mistakes during ventilation

Most typical mistake novice resuscitators is the lack of tightness of the "resuscitator-victim" circuit. Often, the resuscitator forgets to tightly pinch the nose or close the victim's mouth, as a result, he cannot inhale enough air into the victim's lungs, as evidenced by the lack of chest excursions.

The second most common mistake is the unresolved retraction of the victim’s tongue, as a result of which mechanical ventilation is impossible, and air instead of the lungs enters the stomach, as evidenced by the appearance and growth of a protrusion in the epigastric region. In such cases, the victim should be turned on his side and gently but vigorously pressed on the epigastric region to force the air out of the stomach. During this manipulation, the resuscitator must have suction, since gastric contents may flow into the upper respiratory tract.

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Various types of artificial pulmonary ventilation (ALV) make it possible to provide gas exchange to the patient both during surgery and during critical conditions life-threatening. Artificial respiration has saved many lives, but not everyone understands what mechanical ventilation is in medicine, since ventilation of the lungs using special devices appeared only in the last century. Nowadays it's hard to imagine intensive care unit or an operating room without a ventilator.

Why is artificial ventilation needed?

Absence or disturbance of breathing and subsequent cessation of blood circulation for more than 3-5 minutes inevitably lead to irreversible brain damage and death. In such cases, only methods and techniques of artificial ventilation can help save a person. Forcing air into the respiratory system, heart massage help to temporarily prevent the death of brain cells during clinical death, and in some cases breathing and heartbeat can be restored.

The rules and methods of artificial lung ventilation are studied in special courses; the basics of mouth-to-mouth ventilation are used to provide first aid to patients. Speaking about the technique of artificial pulmonary ventilation (ALV) and chest compressions, it is worth remembering that their ratio is 1:5 (one breath and five sternum compressions) for adults and children weighing more than 20 kg, if resuscitation is carried out by two rescuers. If resuscitation is performed by one rescuer, the ratio is 2:15 (two breaths and fifteen chest compressions). Total number compressions of the sternum is 60-80 and can even reach 100 per minute and depends on the age of the patient.

But currently, mechanical ventilation is used not only in resuscitation measures. It makes it possible to carry out complex surgical interventions and is a method of supporting breathing in diseases that cause it to be impaired.

Many people wonder: how long do people connected to a ventilator live? Life can be maintained in this way for as long as desired, and the decision to disconnect from mechanical ventilation is made depending on the patient’s condition.

Indications for mechanical ventilation in anesthesiology

Carrying out surgical interventions requiring general anesthesia, is carried out using anesthetics that are introduced into the body both intravenously and by inhalation. Most anesthetics depress the respiratory function of the body, therefore, to put the patient into medicated sleep, artificial ventilation is required, because the consequences of respiratory depression in both adults and children can lead to decreased ventilation, hypoxia, and disruption of the heart.

In addition, for any operations where multicomponent anesthesia with tracheal intubation and mechanical ventilation is used, mandatory components are muscle relaxants. They relax the patient's muscles, including the chest muscles. This involves mechanical support of breathing.

The indications and consequences of mechanical ventilation in anesthesiology are as follows:

• the need to relax muscles during surgery (myoplegia);
• breathing problems (apnea) that occur during anesthesia or during surgery. The cause may be depression of the respiratory center by anesthetics;
• surgical interventions on the open chest;
• respiratory failure during anesthesia;
• artificial ventilation after surgery, with slow restoration of spontaneous breathing.

Inhalation anesthesia, total intravenous anesthesia with mechanical ventilation are the main methods of pain relief during operations on the chest and abdominal cavity, when the use of muscle relaxants is required to ensure adequate surgical access.

Muscle relaxants allow you to reduce the dose narcotic drugs, help to more easily achieve synchronization of the patient with the anesthesia-respiratory equipment and help make the work more convenient for surgeons.

Indications for mechanical ventilation in intensive care practice

The procedure is recommended for any breathing problems (asphyxia), both sudden and predictable. When breathing is impaired, three stages are observed: obstruction (impaired patency) of the airways, hypoventilation (insufficient ventilation of the lungs) and, as a consequence, apnea (stopping breathing). Indications for mechanical ventilation are any causes of obstruction and subsequent stages. Such a need may arise not only during planned operations, but also in emergency situations, which in fact are already resuscitation. The reasons may be the following:

• Injuries to the head, neck, chest and abdomen;
• Stroke;
• Convulsions;
• Electric shock;
• Overdose of drugs;
• Carbon monoxide poisoning, gas and smoke inhalation;
• Anatomical distortions of the nasopharynx, pharynx and neck;
• Foreign body in the respiratory tract;
• Decompensation of obstructive lung diseases(asthma, emphysema);
• Drowning.

Modes of artificial pulmonary ventilation (ALV) in intensive care differ from its implementation as an anesthetic aid. The fact is that many diseases can cause not a lack of breathing, but respiratory failure, which is accompanied by impaired tissue oxygenation, acidosis, and pathological types of breathing.

For the treatment and correction of such conditions, special regimes Ventilation in intensive care, for example, in the absence of diseases of the respiratory system, uses a pressure-controlled ventilation mode, in which air under pressure is supplied during inhalation, but exhalation is carried out passively. With bronchospasm, inspiratory pressure must be increased to overcome resistance in the airways.

To avoid atelectasis (pulmonary edema during artificial ventilation), it is advisable to increase the expiratory pressure; this will increase the residual volume and prevent the alveoli from collapsing and fluid from leaking into them. blood vessels. Also, the controlled ventilation mode makes it possible to change the tidal volume and respiratory rate, which allows for normal oxygenation in patients.

If it is necessary to carry out ventilation of the lungs in people with acute respiratory failure, it is advisable to give preference to high-frequency mechanical ventilation, since traditional ventilation may be ineffective. The peculiarity of methods that are classified as high-frequency ventilation is the use of high ventilation frequency (exceeds 60 per minute, which corresponds to 1 Hz) and reduced tidal volume.

The methods and algorithm for performing mechanical ventilation in intensive care patients may be different, the indications for its implementation are:

• lack of spontaneous breathing;
• pathological breathing, including tachypnea;
• respiratory failure;
• signs of hypoxia.

Artificial ventilation of the lungs, the algorithm of which depends on the indications, can be carried out either using a device on which the appropriate ventilation parameters are set (they are different for adults and children), or with an Ambu bag. If during anesthesia for short-term interventions the mask method can be used, then in intensive care, tracheal intubation is usually performed.

Contraindications to mechanical ventilation often have an ethical connotation, for example, it is not performed if the patient refuses, in patients when there is no point in prolonging life, for example, in the last stages of malignant tumors.

Complications

Complications after artificial pulmonary ventilation (ALV) can arise due to inconsistency of modes, composition of the gas mixture, and inadequate sanitation of the pulmonary trunk. They can manifest themselves in violation of hemodynamics, heart function, inflammatory processes in the trachea and bronchi, atelectasis.

Despite the fact that artificial ventilation can negatively affect the body, since it cannot fully correspond to normal spontaneous breathing, its use in anesthesiology and resuscitation makes it possible to provide assistance in critical conditions and provide adequate pain relief during surgical interventions.

To get an idea of ​​performing artificial ventilation, watch the video.

Pathways

Nose - the first changes in the incoming air occur in the nose, where it is cleaned, warmed and moistened. This is facilitated by the hair filter, vestibule and turbinates. Intensive blood supply to the mucous membrane and cavernous plexuses of the shells ensures rapid warming or cooling of the air to body temperature. Water evaporating from the mucous membrane humidifies the air by 75-80%. Prolonged inhalation of air with low humidity leads to drying of the mucous membrane, entry of dry air into the lungs, development of atelectasis, pneumonia and increased resistance in the airways.

Pharynx separates food from air, regulates pressure in the middle ear.

Larynx provides vocal function, with the help of the epiglottis preventing aspiration, and closure vocal cords is one of the main components of cough.

Trachea - the main air duct, in which the air is warmed and humidified. Mucosal cells capture foreign substances, and cilia move mucus up the trachea.

Bronchi (lobar and segmental) end in terminal bronchioles.

The larynx, trachea and bronchi are also involved in purifying, warming and humidifying the air.

The structure of the wall of the conducting airways (AP) differs from the structure of the airways of the gas exchange zone. The wall of the conducting airways consists of the mucous membrane, a layer of smooth muscle, submucosal connective and cartilaginous membranes. Epithelial cells The airways are equipped with cilia, which, oscillating rhythmically, push the protective layer of mucus towards the nasopharynx. The mucous membrane of the EP and lung tissue contain macrophages that phagocytize and digest mineral and bacterial particles. Normally, mucus is constantly removed from the respiratory tract and alveoli. The mucous membrane of the EP is represented by ciliated pseudostratified epithelium, as well as secretory cells that secrete mucus, immunoglobulins, complement, lysozyme, inhibitors, interferon and other substances. The cilia contain many mitochondria, which provide energy for their high motor activity(about 1000 movements per 1 minute), which allows you to transport sputum at a speed of up to 1 cm/min in the bronchi and up to 3 cm/min in the trachea. During the day, about 100 ml of sputum is normally evacuated from the trachea and bronchi, and in pathological conditions up to 100 ml/hour.

Cilia function in a double layer of mucus. At the bottom are biologically active substances, enzymes, immunoglobulins, the concentration of which is 10 times higher than in the blood. This determines the biological protective function of mucus. Its top layer mechanically protects the eyelashes from damage. Thickening or reduction of the upper layer of mucus due to inflammation or toxic effects inevitably disrupts the drainage function of the ciliated epithelium, irritates the respiratory tract and reflexively causes coughing. Sneezing and coughing protect the lungs from mineral and bacterial particles.

Alveoli

In the alveoli, gas exchange occurs between the blood of the pulmonary capillaries and the air. The total number of alveoli is approximately 300 million, and their total surface area is approximately 80 m2. The diameter of the alveoli is 0.2-0.3 mm. Gas exchange between alveolar air and blood occurs by diffusion. The blood of the pulmonary capillaries is separated from the alveolar space only thin layer tissue - the so-called alveolar-capillary membrane, formed by the alveolar epithelium, narrow interstitial space and capillary endothelium. The total thickness of this membrane does not exceed 1 micron. The entire alveolar surface of the lungs is covered with a thin film called surfactant.

Surfactant reduces surface tension at the boundary between liquid and air at the end of exhalation, when the volume of the lung is minimal, increases elasticity lungs and plays the role of an anti-edematous factor(does not allow water vapor from the alveolar air to pass through), as a result of which the alveoli remain dry. It reduces surface tension when the volume of the alveoli decreases during exhalation and prevents its collapse; reduces shunting, which improves oxygenation arterial blood at lower pressure and minimal O2 content in the inhaled mixture.

The surfactant layer consists of:

1) the surfactant itself (microfilms of phospholipid or polyprotein molecular complexes at the border with the air);

2) hypophase (deeper hydrophilic layer of proteins, electrolytes, bound water, phospholipids and polysaccharides);

3) the cellular component, represented by alveolocytes and alveolar macrophages.

The main chemical components of surfactant are lipids, proteins and carbohydrates. Phospholipids (lecithin, palmitic acid, heparin) make up 80-90% of its mass. The surfactant also covers the bronchioles with a continuous layer, reduces breathing resistance, and maintains filling

At low tensile pressure, it reduces the forces that cause fluid accumulation in tissues. In addition, surfactant purifies inhaled gases, filters and traps inhaled particles, regulates the exchange of water between the blood and the alveolar air, accelerates the diffusion of CO 2, and has a pronounced antioxidant effect. Surfactant is very sensitive to various endo- and exogenous factors: circulatory disorders, ventilation and metabolism, changes in PO 2 in the inhaled air, and air pollution. With surfactant deficiency, atelectasis and RDS of newborns occur. Approximately 90-95% of alveolar surfactant is recycled, cleared, accumulated and resecreted. The half-life of surfactant components from the lumen of the alveoli of healthy lungs is about 20 hours.

Lung volumes

Ventilation of the lungs depends on the depth of breathing and the frequency of respiratory movements. Both of these parameters can vary depending on the needs of the body. There are a number of volume indicators that characterize the condition of the lungs. Normal average values ​​for an adult are as follows:

1. Tidal volume(DO-VT- Tidal Volume)- volume of inhaled and exhaled air during quiet breathing. Normal values ​​are 7-9ml/kg.

2. Inspiratory reserve volume (IRV) -IRV - Inspiratory Reserve Volume) - the volume that can additionally arrive after a quiet inhalation, i.e. difference between normal and maximum ventilation. Normal value: 2-2.5 l (about 2/3 vital capacity).

3. Expiratory reserve volume (ERV) - Expiratory Reserve Volume) - the volume that can be additionally exhaled after a quiet exhalation, i.e. difference between normal and maximum exhalation. Normal value: 1.0-1.5 l (about 1/3 vital capacity).

4.Residual volume (RO - RV - Residal Volume) - the volume remaining in the lungs after maximum exhalation. About 1.5-2.0 l.

5. Vital capacity of the lungs (VC - VT - Vital Capacity) - the amount of air that can be maximally exhaled after maximal inhalation. VC is an indicator of the mobility of the lungs and chest. Vital capacity depends on age, gender, body size and position, and degree of fitness. Normal values ​​of VC - 60-70 ml / kg - 3.5-5.5 liters.

6. Inspiratory reserve (IR) -Inspiratory capacity (Evd - IC - Inspiration Capacity) - maximum amount air that can enter the lungs after a quiet exhalation. Equal to the sum of DO and ROVD.

7.Total lung capacity (TLC - TLC - Total lung capacity) or maximum lung capacity - the amount of air contained in the lungs at the height of maximum inspiration. Consists of VC and OO and is calculated as the sum of VC and OO. The normal value is about 6.0 l.
The study of the structure of the vital capacity is decisive in elucidating the ways of increasing or decreasing the vital capacity, which can have a significant practical significance. An increase in VC can be regarded positively only if the CL does not change or increases, but is less than the VC, which occurs with an increase in VC due to a decrease in RO. If, simultaneously with an increase in VC, an even greater increase in TLC occurs, then this cannot be considered a positive factor. When vital capacity is below 70% TEL function external respiration deeply disturbed. Usually, in pathological conditions, TL and VC change in the same way, with the exception of obstructive pulmonary emphysema, when VC, as a rule, decreases, VR increases, and TL may remain normal or be above normal.

8.Functional residual capacity (FRC - FRC - Functional residual volume) - the amount of air that remains in the lungs after a quiet exhalation. Normal values ​​for adults are from 3 to 3.5 liters. FFU = OO + ROvyd. By definition, FRC is the volume of gas that remains in the lungs during a quiet exhalation and can be a measure of the area of ​​gas exchange. It is formed as a result of the balance between the oppositely directed elastic forces of the lungs and chest. The physiological significance of FRC is the partial renewal of the alveolar volume of air during inspiration (ventilated volume) and indicates the volume of alveolar air constantly present in the lungs. A decrease in FRC is associated with the development of atelectasis, closure of small airways, a decrease in lung compliance, an increase in the alveolar-arterial difference in O2 as a result of perfusion in atelectasis areas of the lungs, and a decrease in the ventilation-perfusion ratio. Obstructive ventilation disorders lead to an increase in FRC, restrictive disorders - to a decrease in FRC.

Anatomical and functional dead space

Anatomical dead space called the volume of the airways in which gas exchange does not occur. This space includes the nasal and oral cavity, pharynx, larynx, trachea, bronchi and bronchioles. The amount of dead space depends on the height and position of the body. Approximately, we can assume that in a sitting person, the volume of dead space (in milliliters) is equal to twice the body weight (in kilograms). Thus, in adults it is about 150-200 ml (2 ml/kg body weight).

Under functional (physiological) dead space understand all those areas of the respiratory system in which gas exchange does not occur due to reduced or absent blood flow. The functional dead space, in contrast to the anatomical one, includes not only the airways, but also those alveoli that are ventilated but not perfused with blood.

Alveolar and dead space ventilation

The part of the minute volume of respiration that reaches the alveoli is called alveolar ventilation, the rest of it is dead space ventilation. Alveolar ventilation serves as an indicator of the efficiency of breathing in general. The gas composition maintained in the alveolar space depends on this value. As for minute volume, it only to a small extent reflects the effectiveness of ventilation. So, if the minute volume of breathing is normal (7 l/min), but breathing is frequent and shallow (UP to 0.2 l, RR-35/min), then ventilate

There will be mainly dead space, into which air enters before the alveolar; in this case, the inhaled air will hardly reach the alveoli. Because the the volume of dead space is constant, alveolar ventilation is greater, the deeper the breathing and the lower the frequency.

Extensibility (flexibility) lung tissue
Lung compliance is a measure of elastic traction, as well as elastic resistance of the lung tissue, which is overcome during inhalation. In other words, extensibility is a measure of the elasticity of the lung tissue, i.e. its pliability. Mathematically, compliance is expressed as the quotient of the change in lung volume and the corresponding change in intrapulmonary pressure.

Compliance can be measured separately for the lungs and chest. From a clinical point of view (especially during mechanical ventilation), the compliance of the lung tissue itself, which reflects the degree of restrictive pulmonary pathology, is of greatest interest. In modern literature, lung compliance is usually referred to as “compliance” (from English word“compliance”, abbreviated as C).

Lung compliance decreases:

With age (in patients older than 50 years);

In the supine position (due to the pressure of the abdominal organs on the diaphragm);

During laparoscopic surgical interventions due to carboxyperitoneum;

For acute restrictive pathology (acute polysegmental pneumonia, RDS, pulmonary edema, atelectasis, aspiration, etc.);

In chronic restrictive pathology ( chronic pneumonia, pulmonary fibrosis, collagenosis, silicosis, etc.);

With pathology of the organs that surround the lungs (pneumo- or hydrothorax, high standing of the dome of the diaphragm with intestinal paresis, etc.).

The worse the compliance of the lungs, the greater the elastic resistance of the lung tissue must be overcome in order to achieve the same tidal volume as with normal compliance. Consequently, in the case of deteriorating lung compliance, when the same tidal volume is achieved, the pressure in the airways increases significantly.

This point is very important to understand: with volumetric ventilation, when a forced tidal volume is supplied to a patient with poor lung compliance (without high airway resistance), a significant increase in peak airway pressure and intrapulmonary pressure significantly increases the risk of barotrauma.

Airway resistance

The flow of the respiratory mixture in the lungs must overcome not only the elastic resistance of the tissue itself, but also the resistive resistance of the airways Raw (an abbreviation for the English word “resistance”). Since the tracheobronchial tree is a system of tubes of varying lengths and widths, the resistance to gas flow in the lungs can be determined according to known physical laws. In general, flow resistance depends on the pressure gradient at the beginning and end of the tube, as well as on the magnitude of the flow itself.

Gas flow in the lungs can be laminar, turbulent, or transient. Laminar flow is characterized by layered forward movement gas with

Varying speed: the flow speed is highest in the center and gradually decreases towards the walls. Laminar gas flow predominates at relatively low speeds and is described by Poiseuille's law, according to which the resistance to gas flow depends most on the radius of the tube (bronchi). Reducing the radius by 2 times leads to an increase in resistance by 16 times. In this regard, the importance of choosing the widest possible endotracheal (tracheostomy) tube and maintaining the patency of the tracheobronchial tree during mechanical ventilation is clear.
The resistance of the respiratory tract to gas flow increases significantly with bronchiolospasm, swelling of the bronchial mucosa, accumulation of mucus and inflammatory secretions due to narrowing of the lumen of the bronchial tree. Resistance is also affected by flow rate and length of the tube(s). WITH

By increasing the flow rate (forcing inhalation or exhalation), airway resistance increases.

The main reasons for increased airway resistance are:

Bronchiolospasm;

Swelling of the bronchial mucosa (exacerbation of bronchial asthma, bronchitis, subglottic laryngitis);

Foreign body, aspiration, neoplasms;

Accumulation of sputum and inflammatory secretions;

Emphysema (dynamic compression of the airways).

Turbulent flow is characterized by the chaotic movement of gas molecules along the tube (bronchi). It predominates at high volumetric flow rates. In the case of turbulent flow, airway resistance increases, since it depends to an even greater extent on the flow speed and the radius of the bronchi. Turbulent movement occurs at high flows, sudden changes in flow speed, in places of bends and branches of the bronchi, and with a sharp change in the diameter of the bronchi. This is why turbulent flow is characteristic of patients with COPD, when even in remission there is increased airway resistance. The same applies to patients with bronchial asthma.

Airway resistance is unevenly distributed in the lungs. The greatest resistance is created by bronchi of medium caliber (up to the 5th-7th generation), since the resistance of large bronchi is small due to their large diameter, and small bronchi - due to the large total cross-sectional area.

Airway resistance also depends on lung volume. With a large volume, the parenchyma has a greater “stretching” effect on the airways, and their resistance decreases. The use of PEEP helps to increase lung volume and, consequently, reduce airway resistance.

Normal airway resistance is:

In adults - 3-10 mm water column/l/s;

In children - 15-20 mm water column/l/s;

In infants under 1 year - 20-30 mm water column/l/s;

In newborns - 30-50 mm water column/l/s.

On exhalation, the airway resistance is 2-4 mm water column/l/s greater than on inspiration. This is due to the passive nature of exhalation, when the condition of the wall of the airways affects gas flow to a greater extent than during active inhalation. Therefore, it takes 2-3 times longer to fully exhale than to inhale. Normally, the inhalation/exhalation time ratio (I:E) for adults is about 1: 1.5-2. The completeness of exhalation in a patient during mechanical ventilation can be assessed by monitoring the expiratory time constant.

Work of breathing

The work of breathing is performed primarily by the inspiratory muscles during inhalation; exhalation is almost always passive. At the same time, in the case of, for example, acute bronchospasm or swelling of the mucous membrane of the respiratory tract, exhalation also becomes active, which significantly increases general work external ventilation.

During inhalation, the work of breathing is mainly spent on overcoming the elastic resistance of the lung tissue and the resistive resistance of the respiratory tract, while about 50% of the expended energy accumulates in the elastic structures of the lungs. During exhalation, this stored potential energy is released, allowing the expiratory resistance of the airways to be overcome.

The increase in inspiratory or expiratory resistance is compensated extra work respiratory muscles. The work of breathing increases with a decrease in lung compliance (restrictive pathology), an increase in airway resistance (obstructive pathology), and tachypnea (due to dead space ventilation).

Normally, only 2-3% of the total oxygen consumed by the body is spent on the work of the respiratory muscles. This is the so-called “cost of breathing”. During physical work, the cost of breathing can reach 10-15%. And with pathology (especially restrictive), more than 30-40% of the total oxygen absorbed by the body can be spent on the work of the respiratory muscles. In severe diffuse respiratory failure, the cost of breathing increases to 90%. At some point, all the additional oxygen obtained by increasing ventilation goes to cover the corresponding increase in the work of the respiratory muscles. That is why, at a certain stage, a significant increase in the work of breathing is a direct indication for starting mechanical ventilation, at which the cost of breathing is reduced to almost 0.

The work of breathing required to overcome elastic resistance (lung compliance) increases as tidal volume increases. The work required to overcome airway resistance increases with increasing respiratory rate. The patient seeks to reduce the work of breathing by changing the respiratory rate and tidal volume depending on the prevailing pathology. For each situation, there are optimal respiratory rates and tidal volumes at which the work of breathing is minimal. Thus, for patients with reduced compliance, from the point of view of minimizing the work of breathing, more frequent and shallow breathing is suitable (hard lungs are difficult to straighten). On the other hand, when airway resistance is increased, deep and slow breathing is optimal. This is understandable: an increase in tidal volume allows you to “stretch”, expand the bronchi, and reduce their resistance to gas flow; for the same purpose, patients with obstructive pathology compress their lips during exhalation, creating their own “PEEP”. Slow and rare breathing helps to lengthen exhalation, which is important for more complete removal exhaled gas mixture under conditions of increased expiratory airway resistance.

Breathing regulation

The breathing process is regulated by the central and peripheral nervous system. In the reticular formation of the brain there is a respiratory center, consisting of the centers of inhalation, exhalation and pneumotaxis.

Central chemoreceptors are located in the medulla oblongata and are excited when the concentration of H+ and PCO 2 in the cerebrospinal fluid increases. Normally, the pH of the latter is 7.32, PCO 2 is 50 mmHg, and the HCO 3 content is 24.5 mmol/l. Even a slight decrease in pH and an increase in PCO 2 increase ventilation. These receptors respond to hypercapnia and acidosis more slowly than peripheral receptors, as Extra time to measure the values ​​of CO 2, H + and HCO 3 due to overcoming the blood-brain barrier. Contractions of the respiratory muscles are controlled by the central respiratory mechanism, consisting of a group of cells in the medulla oblongata, pons, and pneumotaxic centers. They tone the respiratory center and, based on impulses from mechanoreceptors, determine the threshold of excitation at which inhalation stops. Pneumotaxic cells also switch inspiration to expiration.

Peripheral chemoreceptors, located on the inner membranes of the carotid sinus, aortic arch, and left atrium, control humoral parameters (PO 2, PCO 2 in arterial blood and cerebrospinal fluid) and immediately respond to changes in the internal environment of the body, changing the mode of spontaneous breathing and, thus, correcting pH, PO 2 and PCO 2 in arterial blood and cerebrospinal fluid. Impulses from chemoreceptors regulate the amount of ventilation required to maintain a certain metabolic level. In optimizing the ventilation mode, i.e. establishing the frequency and depth of breathing, the duration of inhalation and exhalation, the force of contraction of the respiratory muscles during this level ventilation, mechanoreceptors are also involved. Ventilation of the lungs is determined by the level of metabolism, the effect of metabolic products and O2 on chemoreceptors, which transform them into afferent impulses of the nervous structures of the central respiratory mechanism. The main function of arterial chemoreceptors is the immediate correction of breathing in response to changes in blood gas composition.

Peripheral mechanoreceptors, localized in the walls of the alveoli, intercostal muscles and the diaphragm, respond to the stretching of the structures in which they are located, to information about mechanical phenomena. Main role mechanoreceptors of the lungs play. The inhaled air enters the VP to the alveoli and participates in gas exchange at the level of the alveolar-capillary membrane. As the walls of the alveoli stretch during inspiration, the mechanoreceptors are excited and send an afferent signal to the respiratory center, which inhibits inspiration (Hering-Breuer reflex).

During normal breathing, intercostal-diaphragmatic mechanoreceptors are not excited and have an auxiliary value.

The regulatory system ends with neurons that integrate impulses that come to them from chemoreceptors and send excitation impulses to respiratory motor neurons. The cells of the bulbar respiratory center send both excitatory and inhibitory impulses to the respiratory muscles. Coordinated excitation of respiratory motor neurons leads to synchronous contraction of the respiratory muscles.

The breathing movements that create air flow occur due to the coordinated work of all respiratory muscles. Motor nerve cells

Respiratory muscle neurons are located in the anterior horns of the gray matter spinal cord(cervical and thoracic segments).

In humans, the cerebral cortex also takes part in the regulation of breathing within the limits allowed by the chemoreceptor regulation of breathing. For example, volitional breath holding is limited by the time during which PaO 2 in the cerebrospinal fluid rises to levels that excite arterial and medullary receptors.

Biomechanics of breathing

Ventilation of the lungs occurs due to periodic changes in the work of the respiratory muscles, volume chest cavity and lungs. The main muscles of inspiration are the diaphragm and the external intercostal muscles. During their contraction, the dome of the diaphragm is flattened and the ribs are raised upward, as a result of which the volume of the chest increases and the negative intrapleural pressure (Ppl) increases. Before the start of inhalation (at the end of exhalation) Ppl is approximately minus 3-5 cm water column. Alveolar pressure (Palv) is taken as 0 (i.e. equal to atmospheric pressure), it also reflects the pressure in the airways and correlates with intrathoracic pressure.

The gradient between alveolar and intrapleural pressure is called transpulmonary pressure (Ptp). At the end of exhalation, it is 3-5 cm of water. During spontaneous inspiration, an increase in negative Ppl (up to minus 6-10 cm water column) causes a decrease in pressure in the alveoli and respiratory tract below atmospheric pressure. In the alveoli, the pressure drops to minus 3-5 cm of water. Due to the pressure difference, air enters (sucks in) from the external environment into the lungs. The chest and diaphragm act as a piston pump, drawing air into the lungs. This “suction” action of the chest is important not only for ventilation, but also for blood circulation. During spontaneous inspiration, additional “suction” of blood to the heart occurs (maintaining preload) and activation of pulmonary blood flow from the right ventricle through the system pulmonary artery. At the end of inhalation, when the movement of gas stops, the alveolar pressure returns to zero, but the intrapleural pressure remains reduced to minus 6-10 cm of water.

Expiration is normally a passive process. After relaxation of the respiratory muscles, the elastic recoil forces of the chest and lungs cause the removal (squeezing) of gas from the lungs and the restoration of the original volume of the lungs. If the patency of the tracheobronchial tree is impaired (inflammatory secretion, swelling of the mucous membrane, bronchospasm), the exhalation process is difficult, and the exhalation muscles (internal intercostal muscles, pectoral muscles, muscles abdominals etc.). When the expiratory muscles are depleted, the process of exhalation is even more difficult, the exhaled mixture is delayed and the lungs are dynamically overinflated.

Non-respiratory functions of the lungs

The functions of the lungs are not limited to the diffusion of gases. They contain 50% of all endothelial cells of the body that line the capillary surface of the membrane and are involved in the metabolism and inactivation of biologically active substances passing through the lungs.

1. The lungs control general hemodynamics by filling their own vascular bed in different ways and by influencing biologically active substances that regulate vascular tone (serotonin, histamine, bradykinin, catecholamines), converting angiotensin I to angiotensin II, and participating in the metabolism of prostaglandins.

2. The lungs regulate blood clotting by secreting prostacyclin, an inhibitor of platelet aggregation, and removing thromboplastin, fibrin and its degradation products from the bloodstream. As a result, the blood flowing from the lungs has higher fibrinolytic activity.

3. The lungs are involved in protein, carbohydrate and fat metabolism, synthesizing phospholipids (phosphatidylcholine and phosphatidylglycerol - the main components of surfactant).

4. The lungs produce and eliminate heat, maintaining the body's energy balance.

5. The lungs cleanse the blood of mechanical impurities. Cell aggregates, microthrombi, bacteria, air bubbles, and fat droplets are retained by the lungs and are subject to destruction and metabolism.

Types of ventilation and types of ventilation disorders

A physiologically clear classification of ventilation types has been developed, based on the partial pressures of gases in the alveoli. In accordance with this classification, the following types of ventilation are distinguished:

1.Normoventilation - normal ventilation, in which the partial pressure of CO2 in the alveoli is maintained at about 40 mmHg.

2. Hyperventilation - increased ventilation that exceeds the metabolic needs of the body (PaCO2<40 мм.рт.ст.).

3. Hypoventilation - reduced ventilation compared to the metabolic needs of the body (PaCO2>40 mmHg).

4. Increased ventilation - any increase in alveolar ventilation compared to the resting level, regardless of the partial pressure of gases in the alveoli (for example, during muscular work).

5.Eupnea - normal ventilation at rest, accompanied by a subjective feeling of comfort.

6. Hyperpnea - an increase in the depth of breathing, regardless of whether the frequency of respiratory movements is increased or not.

7.Tachypnea - increase in respiratory rate.

8.Bradypnea - decreased respiratory rate.

9. Apnea - cessation of breathing, caused mainly by the lack of physiological stimulation of the respiratory center (decrease in CO2 tension in arterial blood).

10.Dyspnea (shortness of breath) is an unpleasant subjective feeling of insufficient breathing or difficulty breathing.

11. Orthopnea - severe shortness of breath associated with stagnation of blood in the pulmonary capillaries as a result of left heart failure. IN horizontal position this condition is getting worse, and therefore it is difficult for such patients to lie down.

12. Asphyxia - cessation or depression of breathing, associated mainly with paralysis of the respiratory centers or closure of the airways. Gas exchange is sharply impaired (hypoxia and hypercapnia are observed).

For diagnostic purposes, it is advisable to distinguish between two types of ventilation disorders - restrictive and obstructive.

The restrictive type of ventilation disorders includes all pathological conditions in which the respiratory excursion and the ability of the lungs to expand are reduced, i.e. their extensibility decreases. Such disorders are observed, for example, with lesions of the pulmonary parenchyma (pneumonia, pulmonary edema, pulmonary fibrosis) or with pleural adhesions.

The obstructive type of ventilation disorders is caused by a narrowing of the airways, i.e. increasing their aerodynamic resistance. Similar conditions occur, for example, with the accumulation of mucus in the respiratory tract, swelling of their mucous membrane or spasm of the bronchial muscles (allergic bronchiolospasm, bronchial asthma, asthmatic bronchitis, etc.). In such patients, the resistance to inhalation and exhalation is increased, and therefore, over time, the airiness of the lungs and their FRC increase. Pathological condition, characterized by an excessive decrease in the number of elastic fibers (disappearance of alveolar septa, unification of the capillary network), is called pulmonary emphysema.

If the patient's breathing is impaired, mechanical ventilation or artificial respiration is performed. It is used when the patient is unable to breathe on his own or when he is under anesthesia, causing shortage oxygen.

There are several types of mechanical ventilation - from conventional manual ventilation to hardware ventilation. Almost anyone can handle the manual one; the hardware one requires an understanding of how medical equipment works.

This is an important procedure, so you need to know how to perform mechanical ventilation, what is the sequence of actions, how long do patients connected to mechanical ventilation live, and also in which cases the procedure is contraindicated and in which it is performed.

What is mechanical ventilation

In medicine, mechanical ventilation is the artificial injection of air into the lungs to ensure gas exchange between the alveoli and the environment.

Artificial ventilation is also used as a resuscitation measure if the patient has serious breathing problems, or as a means of protecting the body from lack of oxygen.

A state of oxygen deficiency appears during spontaneous diseases or during anesthesia. Artificial ventilation has direct and hardware forms.

The first involves squeezing/unclamping the lungs, allowing passive inhalation and exhalation without the help of a device. The hardware room uses a special gas mixture, which enters the lungs through an artificial ventilation device (these are a kind of artificial lungs).

When is artificial ventilation performed?

The following indications for artificial ventilation exist:

After operation

The endotracheal tube of the ventilator is inserted into the patient's lungs in the operating room or after the patient is transported to the observation ward after anesthesia or the intensive care unit.

The goals of mechanical ventilation after surgery are:

• Elimination of coughing up secretions and sputum from the lungs, reducing the incidence of infectious complications;
• Creating conditions favorable for tube feeding in order to normalize peristalsis and reduce the incidence of gastrointestinal disorders;
• Reducing the negative impact on skeletal muscles occurring after prolonged action of anesthetics;
• Reducing the risk of deep inferiority venous thrombosis, reducing the need for cardiovascular support;
• Accelerated normalization mental functions, as well as normalization of the state of wakefulness and sleep.

For pneumonia

If a patient develops severe pneumonia, acute respiratory failure may soon develop.

For this disease, indications for artificial ventilation are:

• Mental and consciousness disorders;
• Critical blood pressure level;
• Intermittent breathing more than 40 times/min.

Artificial ventilation is carried out at an early stage of the disease to improve efficiency and reduce the risk of death. Mechanical ventilation lasts 10-15 days, and 3-5 hours after placing the tube, tracheostomy is performed.

For stroke

In the treatment of stroke, connecting to a ventilator is a rehabilitation measure.

It is necessary to use artificial ventilation in the following cases:

• Lung lesions;
• Internal bleeding;
• Pathologies respiratory function body;
• Coma.

During a hemorrhagic or ischemic attack, the patient has difficulty breathing, which is restored by a ventilator to provide cells with oxygen and normalize brain functions.

In case of stroke, artificial lungs are placed for a period of less than two weeks. This period is characterized by a decrease in brain swelling and cessation of acute period diseases.

Types of artificial ventilation devices

In resuscitation practice, the following artificial respiration devices are used, which deliver oxygen and remove it from the lungs carbon dioxide:

1. Respirator. A device that is used for long-term resuscitation. Most of these devices operate on electricity and can be adjusted in volume.

According to the method of device, respirators can be divided into:

• Internal acting with endotracheal tube;
• External action with a face mask;
• Electrostimulators.

1. High frequency equipment. Makes it easier for the patient to get used to the device, significantly reduces intrathoracic pressure and tidal volume, and facilitates blood flow.

Ventilation modes in intensive care

An artificial respiration device is used in intensive care; it is one of the mechanical methods of artificial ventilation. It includes a respirator, endotracheal tube or tracheostomy cannula.

Newborns and older children may experience the same breathing problems as adults. In such cases, different devices are used, which differ in the size of the inserted tube and the breathing frequency.

Hardware artificial ventilation is carried out in a mode of over 60 cycles/min. in order to reduce tidal volume, pressure in the lungs, facilitate blood circulation and adapt the patient to the respirator.

Basic methods of mechanical ventilation

High frequency ventilation can be carried out in 3 ways:

• Volumetric . The respiratory rate ranges from 80 to 100 per minute.
• Oscillatory . Frequency 600 – 3600 rpm. with intermittent or continuous flow vibration.
• Inkjet . From 100 to 300 per minute. The most popular ventilation involves using a thin catheter or needle to inject a mixture of gases or oxygen into the airways under pressure. Other options are a tracheostomy, endotracheal tube, or a catheter through the skin or nose.

In addition to the methods discussed, there are resuscitation modes based on the type of device:

1. Auxiliary– the patient’s breathing is maintained, gas is supplied when the person tries to take a breath.
2. Automatic – breathing is completely suppressed pharmacological drugs. The patient breathes fully using compression.
3. Periodic forced– used during the transition to completely independent breathing from mechanical ventilation. A gradual decrease in the frequency of artificial breaths forces a person to breathe on his own.
4. Electrical stimulation of the diaphragm– electrical stimulation is carried out using external electrodes, causing the diaphragm to contract rhythmically and irritating the nerves located on it.
5. With PEEP - intrapulmonary pressure in this mode remains positive relative to atmospheric pressure, which makes it possible to better distribute air in the lungs and eliminate edema.

Ventilator

In the recovery room or intensive care unit, a mechanical ventilation device is used. This equipment is necessary to supply a mixture of dry air and oxygen to the lungs. A forced method is used to saturate the blood and cells with oxygen and remove carbon dioxide from the body.

There are several types of ventilators:

• Depending on the type of equipment - tracheostomy, endotracheal tube, mask;
• Depending on age - for newborns, children and adults;
• Depending on the operating algorithm - mechanical, manual, and also with neuro-controlled ventilation;
• Depending on the purpose - general or special;
• Depending on the drive – manual, pneumomechanical, electronic;
• Depending on the scope of application - intensive care unit, intensive care unit, postoperative unit, newborns, anesthesiology.

The procedure for performing mechanical ventilation

For performing mechanical ventilation doctors use special medical devices. After examining the patient, the doctor determines the depth and frequency of inhalations and selects the composition of the gas mixture. The breathing mixture is supplied using a hose that is connected to a tube. The device controls and regulates the composition of the mixture.

When using a mask that covers the mouth and nose, the device is equipped with an alarm system that reports respiratory failure. For prolonged ventilation, an air duct is inserted through the wall of the trachea.

Possible problems

After installing the ventilator and during its operation, the following problems may occur:

1. Desynchronization with a respirator . May lead to inadequate ventilation and decreased breathing volume. The causes are considered to be holding your breath, coughing, lung pathologies, incorrectly installed apparatus, and bronchospasms.
2. The presence of a struggle between a person and a device . To correct it, it is necessary to eliminate hypoxia, as well as check the parameters of the device, the equipment itself and the position of the endotracheal tube.
3. Increased airway pressure . Appears due to bronchospasm, violations of the integrity of the tube, hypoxia, pulmonary edema.

Negative consequences

The use of a ventilator or other method of artificial ventilation can cause the following complications:

Weaning the patient from mechanical ventilation

The indication for weaning the patient is the positive dynamics of indicators:

• Reduce minute ventilation to 10 ml/kg;
• Restoration of breathing to a level of 35 per minute;
• The patient does not have an infection or elevated temperature, apnea;
• Stable blood counts.

Before weaning, it is necessary to check the remains of the muscle blockade, and also reduce the dose of sedatives to a minimum.

Video

Lecture No. 6

Subject " Cardiopulmonary resuscitation »

1) The concept of resuscitation.

2) Tasks of resuscitation.

3) Technique for artificial ventilation.

4) External cardiac massage technique.

Lecture.

Resuscitation- This is a complex of therapeutic measures aimed at restoring cardiac activity, breathing and vital functions of an organism in a terminal state.

In a terminal condition, regardless of its cause, pathological changes occur in the body, affecting almost all organs and systems (brain, heart, respiratory system, metabolism, etc.) and occurring in tissues over different periods of time. Considering that organs and tissues continue to live for some time even after complete cardiac and respiratory arrest, with timely resuscitation it is possible to achieve the effect of reviving the patient.

Resuscitation tasks:

ensuring free airway patency;

performing mechanical ventilation;

restoration of blood circulation.

Signs of life:

presence of heartbeat - determined by listening to heart sounds over the heart area;

the presence of a pulse in the arteries: radial, carotid, femoral.

the presence of breathing: determined by the movement of the chest, anterior abdominal wall, by bringing a fluff of cotton wool, a thread, or a mirror to the nose and mouth (fog up) by the movement of the air flow.

the presence of a reaction of the pupils to light (constriction of the pupil to a beam of light is a positive reaction. During the day, close the eye with your palm => when abducted => change in the pupil).

Stages of cardiopulmonary resuscitation:

1. Ensure airway patency:

Free the oral cavity and pharynx from foreign matter (blood, mucus, vomit, dentures, chewing gum) with your hand wrapped in a napkin or handkerchief, after turning the person being rescued’s head to the side.

After this, perform the triple Safar maneuver:

1) Tilt your head back as much as possible to straighten the airways;

2) Push the lower jaw forward to prevent tongue retraction;

3) Open your mouth slightly.

Using the “mouth to mouth” (“mouth to mouth”) method, the rescuer pinches the patient’s nose, takes a deep breath, presses his lips to the patient’s mouth through a napkin or a clean handkerchief and exhales air into it with force. In this case, it is necessary to monitor whether the chest rises when the patient inhales. It is more convenient to check the ventilation using the Safar S-shaped air duct, because it prevents the tongue from retracting.

IVL method "mouth to nose" ("mouth to nose"), the rescuer closes the patient's mouth, pushing the lower jaw forward, covers the patient's nose with his lips and blows air into it.

In young children, air is blown into the mouth and nose at the same time carefully, so as not to rupture the lung tissue.

3. Indirect massage hearts:

done simultaneously with mechanical ventilation. The patient should lie on a hard surface (floor, board).

The rescuer puts his hand on the lower part of the sternum, the second on top of it and jerkily presses on the sternum with the whole weight of his body with a frequency of 60 times in 1 minute.

If the rescuer is alone, after two blows of air, 10 - 12 pressures on the sternum should be done.

If two people provide assistance => one does mechanical ventilation, the second does cardiac massage. After every 4-6 compressions on the sternum, take one breath. Resuscitation is carried out until breathing and heartbeat are restored. If signs of biological death appear, resuscitation is stopped.

Technique for artificial lung ventilation.

Artificial ventilation of the lungs using the “mouth to mouth” or “mouth to nose” method. To carry out artificial ventilation of the lungs, it is necessary to lay the patient on his back, unfasten the clothes that are constricting the chest and ensure free passage of the airways. The contents in the mouth or throat must be quickly removed with a finger, a napkin, a handkerchief, or using any suction (you can use a rubber syringe, having previously cut off its thin tip). To clear the airway, the victim's head should be pulled back. It must be remembered that excessive abduction of the head can lead to narrowing of the airways. For a more complete opening of the airways, it is necessary to move the lower jaw forward. If one of the types of air vents is available, it should be inserted into the pharynx to prevent the tongue from retracting. If there is no air vent, during artificial respiration you should keep your head in an abducted position, moving the lower jaw forward with your hand.

To perform mouth-to-mouth breathing, the victim’s head is held in a certain position. The resuscitator, taking a deep breath and pressing his mouth tightly to the patient’s mouth, blows exhaled air into his lungs. In this case, you need to hold your nose with your hand near the victim’s forehead. Exhalation is carried out passively, due to the elastic forces of the chest. The number of breaths per minute should be at least 16-20. Insufflation must be carried out quickly and sharply (in children less sharply), so that the duration of inhalation is 2 times less than the exhalation time.

It is necessary to ensure that the inhaled air does not lead to excessive distension of the stomach. In this case, there is a danger of food masses entering the bronchi from the stomach. Of course, mouth-to-mouth breathing creates significant hygienic inconveniences. You can avoid direct contact with the patient’s mouth by blowing air through a gauze pad, handkerchief or any other loose fabric.

When using the mouth-to-nose breathing method, air is blown through the nose. In this case, the victim’s mouth should be closed with a hand, which simultaneously moves the lower jaw forward to prevent the tongue from retracting.

Artificial ventilation of the lungs using manual respirators.

It is necessary to ensure airway patency. A mask is placed tightly over the patient's nose and mouth. Squeezing the bag, inhale, exhale through the valve of the bag, while the duration of exhalation is 2 times longer than the duration of inhalation.

Under no circumstances should artificial respiration be started without clearing the airways (mouth and throat) from foreign bodies or food masses.

External cardiac massage technique.

The meaning of external cardiac massage is the rhythmic compression of the heart between the sternum and the spine. In this case, blood is expelled from the left ventricle into the aorta and enters, in particular, into the brain, and from the right ventricle into the lungs, where it is saturated with oxygen. After the pressure on the sternum stops, the cavities of the heart fill with blood again. When providing external massage, the patient is placed on his back on a solid base (floor, ground). Massage cannot be performed on a mattress or soft surface. The resuscitator stands on the side of the patient and, using the palmar surfaces of his hands, superimposed on one another, presses on the sternum with such force as to bend it towards the spine by 4-5 cm. The frequency of compressions is 50-70 times per minute. Hands should lie on the lower third of the sternum, i.e. 2 transverse fingers above the xiphoid process. In children, heart massage should be performed with only one hand, and in infants - with the tips of two fingers at a frequency of 100-120 pressures per minute. The point of application of the fingers in children under 1 year old is at the lower end of the sternum. If resuscitation is carried out by one person, then after every 15 pressures on the sternum, he must, after stopping the massage, take 2 strong, quick breaths using the “mouth to mouth”, “mouth to nose” method or with a special hand-held respirator. If two people are involved in resuscitation, one insufflation into the lungs should be made after every 5 compressions on the sternum.

Test questions for consolidation:

What are the main tasks of resuscitation?

Describe the sequence of provision of artificial lung ventilation

Explain what resuscitation is.

Educational literature for students of medical schools V. M. Buyanov;

Additional;

Electronic resources.