Stages of anesthesia: highlights. Stages of anesthesia

Regulation of the depth and duration of general anesthesia is possible, but for this it is necessary to determine what stage of anesthesia the patient is currently in.

The stages of anesthesia in animals and humans always develop in a regular manner, and they are specific for each drug or their combinations. The action of all anesthetics is fundamentally the same.

The classical concept of "anesthesia clinic" (manifestations of signs of anesthesia, cited earlier in the literature) has undergone significant changes in meaning due to the use in practice of several drugs of multidirectional action simultaneously, complementing each other. This makes it difficult to assess the depth of anesthesia and its adequacy to surgical trauma. The clinical picture is described in detail on the example of inhalation anesthesia with ether. There are four main clinical stages of anesthesia. Let's consider stages I and III.

In stage I - stages of analgesia(intoxication, stadium incipiens, hypnotic phase - according to V. S. Galkin), the anesthetized patient loses orientation in the environment. He gradually falls into a drowsy state, from which he can be easily aroused by a loud sound. At the end of this stage, consciousness is turned off and analgesia occurs.

Stage I of anesthesia is characterized by a gradual darkening of consciousness, which, however, is not completely turned off. Tactile, temperature sensitivity and reflexes are preserved, pain sensitivity is sharply weakened (hence the name of the stage). Pupils are the same as before anesthesia or slightly enlarged, react to light. Pulse and breathing are somewhat quickened. In the stage of analgesia, short-term surgical operations and interventions are performed (incision, opening, reduction of dislocation). It corresponds to the concept of "stunning" (raush anesthesia). With ether anesthesia in combination with relaxants and other drugs at this stage, you can perform large operations, including intrathoracic ones.

With continued anesthesia, stage II occurs - excitation(stadium excitationis), when all physiological processes are activated: noticeably excited, noisy breathing, rapid pulse, all types of reflex activity are intensified. At this stage, inhibition develops in the cerebral cortex of the brain, resulting in inhibition of conditioned reflex activity and disinhibition of the subcortical centers.

The patient's behavior resembles a strong degree of alcoholic intoxication: the subconscious is turned off, motor excitation is pronounced, accompanied by an increase in muscle tone. The veins of the neck are filled, the jaws are compressed, the eyelids are closed, the pupils are dilated, the pulse is rapid and tense, blood pressure is increased, cough and gag reflexes are enhanced, breathing is rapid, short-term respiratory arrest (apnea) and involuntary urination are possible.

III stage - sleep stage, or tolerant(stadium tolerans, surgical, endurance stage) - begins due to the development of inhibition in the cortex and subcortex. Excitation stops, physiological functions stabilize. In practice, all anesthetics are selected so that this stage is the longest.

The activity of the centers of the medulla oblongata is preserved. Pain sensitivity disappears first on the back, then on the limbs, chest, abdomen. The state of the pupil is very important in this period: if the pupil is narrow and does not respond to light, this indicates the correct course of anesthesia. The expansion of the pupil and the appearance of a reaction to light precedes the awakening of the patient; Pupil dilation in the absence of reaction to light is the first important signal of threatening respiratory arrest.

Important indicators of the depth of anesthesia, along with the pupillary reflex, are changes in respiration, blood circulation, skeletal muscle tone, the condition of the mucous membranes and skin. An important role here is played by the results of special studies (if it is possible to conduct them): encephalography, oximetry, electrocardiography, etc. In stage III, different authors distinguish 3 ... 4 levels.

Surface level III stage (III-1 - level of eyeball movement) is characterized by the fact that the movement of the eyeballs is preserved, the pupils are constricted, they react to light. Only surface reflections are missing. Breathing is even, quickened, the pulse is somewhat quickened, blood pressure is normal, the skin is pink. The patient is in a state of calm even sleep, corneal, pharyngeal-laryngeal reflexes are preserved and muscle tone is somewhat reduced. You can perform short-term and low-traumatic operations.

Intermediate level III stage (III-2 - level of corneal reflex) is characterized by the fact that there is no movement of the eyeballs, the pupils are constricted, the reaction to light is preserved. Breathing is slow. Blood pressure and pulse are normal. Sometimes there is a short pause after exhalation. Reflex activity and muscle tone disappear, hemodynamics and respiration are satisfactory. It is possible to perform operations on the abdominal organs without the use of muscle relaxants.

On the deep (3rd) level III stage (III-3 - pupil dilation level) the toxic effect of the ether is manifested - the pupils gradually expand, their reaction to light fades, the conjunctiva is moist. The rhythm and depth of breathing is disturbed, costal breathing weakens, diaphragmatic breathing predominates. Tachycardia increases, the pulse is somewhat quickened, blood pressure slightly decreases. The muscle tone is sharply reduced (atony), only the tone of the sphincters is preserved. The skin is pale. This level is acceptable for a short time with obligatory assisted breathing.

On the 4th level III stage (III-4 - level of diaphragmatic breathing) the maximum inhibition of physiological functions is manifested; pupils are dilated, there is no reaction to light, the cornea is dry. Paralysis of intercostal muscles progresses, costal breathing is absent, contractility of the diaphragm decreases, diaphragmatic breathing is speeded up, superficial. Blood pressure decreases (hypotension), the skin is pale or cyanotic. Sphincters are paralyzed.

As anesthesia deepens, IV agonal stage(stadium agonalis). There is a paralysis of the respiratory and vasomotor centers: breathing is superficial, intermittent with long periods of apnea, up to a complete stop; arrhythmia, fibrillation and cardiac arrest are consistently observed; pulse first thready, then disappears; blood pressure drops rapidly and death occurs.

Under the action of other anesthetics, these same stages are expressed somewhat differently. For example, with intravenous administration of barbiturates in stage I, the patient quickly falls asleep calmly, breathing is slightly depressed, laryngeal and pharyngeal reflexes are increased, and hemodynamics is stable. In stage II, some dilation of the pupils is distinguished, reflex activity is preserved, respiratory arrhythmia appears, sometimes up to a short-term apnea, there may be motor reactions to pain. In stage III, the reaction to pain completely disappears, moderate muscle relaxation is observed, breathing becomes shallow, myocardial function is somewhat depressed, resulting in hypotension. With further strengthening of anesthesia with barbiturates, apnea and asystole are observed. This also happens with the rapid introduction of these drugs in high concentrations.

It is impossible and unnecessary to describe the clinical manifestation of anesthesia for all drugs and their combinations. The clinical picture of inhalation anesthesia with ether most fully reflects all stages, and on its basis it is possible to trace and evaluate the body's response to other drugs in each specific case.

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The effect of narcotic substances on the central nervous system, resulting in a blackout of consciousness, relaxation of muscle tone, dulling of pain sensitivity, is called anesthesia or anesthesia. Narcosis is distinguished between inhalation and non-inhalation, the concepts differ in the method of introducing drugs into the body. Also, anesthesia is divided into two groups: general and local.

Ether anesthesia

For many decades, ether anesthesia was the most common form of general anesthesia. Its therapeutic breadth and simplicity in anesthetic technique have made it the most preferred among many other anesthetic drugs. But due to the fact that modern honey. institutions have wide opportunities for anesthesia, and the technique for introducing anesthesia has become more perfect, the negative aspects of ether have become more and more clearly manifested. First of all, this refers to a longer immersion of the patient in anesthesia, and a rather slow manifestation of the effect of anesthesia. It is worth noting the long and difficult exit of the patient from the narcotic state, also, the ether is irritable for the mucous membranes.

Stages of ether anesthesia

After the introduction into anesthesia, the patient has characteristic changes in all systems of the human body. According to how much the body is saturated with narcotic substances, there are several stages of anesthesia, according to which its depth is determined. The most characteristic change in stages can be observed with the introduction of ether mononarcosis. For over 100 years, people have been using the classification of the stage of anesthesia, which is most clearly seen when using ether. This Guedel classification includes 4 stages:

• Analgesia. This phase does not last long, only 3 to 8 minutes. At this moment, the patient's consciousness is gradually depressed, he is in a doze, the answers to the questions are short and monosyllabic. Only reflex functions, tactile and temperature sensitivity remain unchanged. The pulse and blood pressure indicators remain normal. It is at this stage that you can perform short surgical interventions, for example: opening pustules, phlegmon, and conducting various diagnostic studies.
• Excitations. The stage of analgesia is followed by the second stage, which is called excitation. Stronger and most often this stage manifests itself during the use of ether anesthesia. At this moment, inhibition of the cerebral cortex is observed, but the subcortical centers are still functioning. This fact leads to the fact that the patient is excitation of the motor apparatus and speech. In the stage of excitement, the consciousness of the patients is lost, but, nevertheless, they try to get up, while screaming loudly. There is hyperemia of the skin, pulse and blood pressure are slightly elevated. Some expansion of the pupil is noted, the light reaction is preserved, sometimes lacrimation occurs. Due to increased bronchial secretion, a cough begins, and vomit may be released.
  While this stage proceeds, surgical intervention is not performed. It is necessary to continue saturating the patient's body with anesthesia. Depending on how experienced the anesthesiologist is and based on the condition of the patient, we can talk about the duration of this phase. Most often it lasts from 5 to 15 minutes.
• Surgical. The next stage is surgical. There are also 4 grades. It is after this stage has been reached that any surgical intervention is possible.
  As soon as the stage of surgery begins, the patient is pacified, his breathing is calm, the pulse and blood pressure indicators return to their original position.

1. The first degree is characterized by the fact that the patient's eyeballs move smoothly, the pupil is noticeably narrowed, the reaction to light is good. Reflex functions are preserved, and the muscles are in good shape.
2. Second degree - the eyeballs stop moving, are located in a strictly central position. At the same time, the pupils begin to dilate again, the light reaction is rather weak. Some reflexes begin to disappear: corneal and swallowing, subsequently, at the end of the second stage, they disappear completely. Against this background, the patient's breathing remains calm and measured, muscle tone is noticeably reduced. Pulse and blood pressure indicators are normal. Since the muscle tone is noticeably weakened, at this moment strip operations are performed in the abdominal cavity.
3. The third degree is called the level of deep anesthesia. When the patient comes to this stage and precisely to this degree, his pupils react only to a bright glow, there is no corneal reflex. It is at this stage that all the muscles of the skeleton and even the intercostal muscles relax. The patient's breathing is not deep, diaphragmatic. Since at this moment all the muscles are relaxed, the lower jaw sags slightly, which in turn leads to the retraction of the tongue. The sunken tongue completely covers the larynx, which invariably causes suffocation, a person may suffocate at the moment. In order to avoid complications, the lower jaw is pushed forward a little, and it is fixed in this position throughout the entire surgical intervention. The pulse quickens a little, blood pressure goes down.
4. Fourth degree. It must be said right away that immersing a patient in the fourth degree of anesthesia is very dangerous for his life, since there is a possibility of respiratory and circulatory arrest. At this stage, the patient's breathing is superficial, due to the paralysis of the intercostal muscles, he carries out respiratory movements due to the contraction of the diaphragm. The cornea of ​​the eye is no longer able to respond to light, the tissues are dry. The pulse becomes thready, blood pressure drops, and sometimes it is not detected at all. Symptoms of the fourth degree of immersion in anesthesia fully correspond to the agonal stage. In the latter, there are significant changes in the cells of the central nervous system. The last degree is marked by an excessive deepening of anesthesia, which leads to irreversible consequences in the human body.

• Awakening stage. Depending on the state of the patient and what dose of anesthesia he received, this phase can take a few minutes, and often stretching hours. The awakening phase begins immediately after the cessation of the anesthetic supply, at which time consciousness is restored, and in reverse order, all functions in the patient's body are restored.

Also, it is worth noting that in the stage of analgesia, 3 more degrees are distinguished:

1. the first degree - there is no anesthesia and loss of consciousness yet
2. second degree - complete anesthesia occurs and consciousness is partially lost
3. the third degree - there is already complete anesthesia and complete loss of consciousness.
   For the first time, degrees in the stage of analgesia were discovered and described by Artusio, in 1954.

Anesthesia with Sevoran

So the echoes of civilization have come to us, a new inhalation anesthetic called "Sevoran" has appeared. This drug has found its wide application in short-term surgical intervention. It is most often used in dentistry, as well as in the application of reconstructive operations.

Many physicians prefer intravenous anesthetics in combination with sevoran. Usually, older children can safely endure the installation of an intravenous catheter, babies are usually given inhalation anesthesia with sevoran, and only then, the catheter is installed. With this introduction, the patient quickly enters the phase of rapid anesthesia, he quickly begins the phase of preventing a response to a skin incision, and as a result, blockade of the reaction to pain. This drug is the least toxic and promotes rapid awakening from anesthesia. The drug has no pronounced odor, and is also non-flammable, and this is a rather important argument when working with a laser. The depth of the narcotic state is determined by the level of the sevoran substance in the mixture that the patient inhales. Depending on the dose of sevoran, there is a decrease in blood pressure and a decrease in respiratory function in the patient, while intracranial pressure remains unchanged. Just like with anesthesia, with any other anesthetic, during the operation, the patient's condition is continuously monitored, and any deviation from the norm is immediately captured by modern equipment and the data is displayed on multifunctional monitors. Complications when using sevoran during general anesthesia are extremely rare, most often after surgery there are such ailments as: drowsiness, nausea, headache, but these symptoms disappear after 30-50 minutes. The use of this drug during anesthesia is not capable of somehow negatively affecting the patient's future life.

Each stage has its own characteristics and is due to the involvement of certain structures of the spinal cord in inhibition.

Induction anesthesia is the most responsible period of general anesthesia. By analogy with aviation, where the takeoff and landing of an aircraft are the most dangerous, in anesthesiology, the periods of introduction into anesthesia and withdrawal from it are considered as such.

The most widespread in our days received a non-inhalation intravenous route of anesthesia. He attracted the attention of anesthetists, since with this method the stage of excitation is not clinically manifested. Of the drugs for intravenous induction anesthesia, ultrashort-acting barbiturates are used - 1-2% solutions of hexasnal or sodium thiopental. The introduction (slow) of these drugs is stopped as soon as the patient loses consciousness. Usually, 200-400 mg of drugs are consumed on average.

It has become widespread in recent years neuroleptanalgesia technique, in which droperidol (10-20 mg), fentannl (0.2-0.4 mg), nitrous oxide with oxygen in a ratio of 2:1 or 3:1 are used to introduce the patient into anesthesia. Many supporters also have a method of ataralyesia, in which instead of the neuroleptic droperndol, ataraxon seduxen (diazepam) is used at a dose of 10-25 mg.

In pediatric anesthesiology for induction purposes widely used mask inhalation method. Of the anesthetics, preference is given to halothane (0.5-2% by volume), with the help of which children are quickly, in 2-3 minutes, easily and calmly, without visible excitement, injected into anesthesia. Ketamine anesthesia also deserves attention. The drug is administered intramuscularly (5-7 mg/kg) or intravenously (2 mg/kg).

For short term anesthesia, especially in outpatient practice during artificial termination of pregnancy and in brochological studies, propanidide (epontol, sombrevin) is widely used. The drug is administered intravenously at the rate of 8-10 mg/kg at a rate of 30-50 mg/s, i.e. 500 mg of the drug is administered over 15-30 seconds. This dose induces narcotic sleep lasting 4-6 minutes. To prolong anesthesia, half the initial dose is administered.

Thus, anesthesiologist there is a sufficient choice of means for an introduction anesthesia. To be able to choose the most optimal method of induction anesthesia for each patient is already half the success of the upcoming anesthesia and surgery.

For the first analgesic stage outwardly pronounced state of stupor is characteristic. The patient is as if in a stupor or shows some anxiety. Breathing is deep and rhythmic, the pulse is quickened, the movement of the eyeball is arbitrary. Muscle tone remains the same or slightly increased. Reflexes are saved. Pain sensations are dulled or disappear, while tactile and temperature receptions are not disturbed. Analgesia develops in connection with the switching off of pain sensitivity centers in the stem part of the reticular formation and visual tubercles, while the bioelectrical activity of the cerebral cortex even increases. The course of induction anesthesia can be complicated by the inability to move the jaw with microgenia, ankylosis of the temporomandibular joint. This causes the root of the tongue, the epiglottis, to sink. To combat this, the maximum extension of the head is used, the tongue is pulled out if possible, the introduction of a nasal catheter, and assisted ventilation.

The second stage - motor excitation comes with further receipt of funds. It is manifested by an increase in skeletal muscle tone, erratic contractions of the limbs, attempts to stand up, or uncoordinated movements in space. Breathing and pulse are uneven. Blood pressure is elevated. There is a "wandering" of the eyeballs. The pupil is dilated. Increased secretion of the salivary, lacrimal, bronchial and sweat glands. Frequent swallowing. Against this background, there is a deepening of analgesia. Urination, vomiting, reflex respiratory arrest, ventricular fibrillation, and even death are possible.

As the effect of the anesthetic increases, the third stage is surgical anesthesia. In anesthesiology, this stage is divided into 4 levels:

1. Surface anesthesia. Completely disappears pain and tactile sensitivity. Swallowing stops. The corneal reflex (closing of the eyelids to touch the hair to the cornea) disappears. The eyeballs deviate in an eccentric position, the pupils constrict. Breathing is deep, rhythmic, snoring due to the relaxation of the vocal cords. Blood pressure stabilizes, pulse is quickened. Skeletal muscles are not relaxed. Saved reflexes of the anal sphincter, as well as viscero-visceral to stretch the peritoneum and mesentery.

2. Light anesthesia. The eyeballs are set in a central position. The pupils are constricted and weakly react to light. Skeletal muscles are relaxed, but not completely. Loss of the reflex to stretch the peritoneum. Breathing and pulse are rhythmic. You can do superficial operations.

3. Full anesthesia. Breathing is even, superficial, becoming more frequent when CO 2 is added to the inhaled air. The pulse is rhythmic, but its filling decreases, blood pressure is reduced. Reflexes from the surface and body cavities do not appear, but they persist from the aortic and carotid sinus zones, ensuring the functioning of the centers of respiration and blood circulation. You can cause weakened reflexes of the bladder and rectum. The pupils of the eyes begin to dilate. Skeletal muscles are relaxed, retraction of the tongue is possible if it is not fixed, and asphyxia due to blocking the passage of air into the larynx.

4. Superdeep anesthesia- a state on the verge of life and death. Breathing is shallow, jerky, diaphragmatic. The pulse is weak, small filling, blood pressure is low. Cyanosis of the mucous membranes. The movements of the eyeballs are not manifested and they are in their usual position, the cornea is dry, the pupil is dilated.

Inhalation anesthesia is maintained at the desired level by special devices (evaporators, rotameters - a device for determining volume flow gas or liquids per unit of time), which make it possible to precisely control the concentration of vapors of liquid (vapor-forming) anesthetics or gaseous anesthetic agents in the respiratory mixture. Anesthesia-respiratory devices allow you to control various parameters of artificial lung ventilation - ALV, and modern anesthetic monitors - the concentration of gases (oxygen, nitrous oxide, carbon dioxide and anesthetic vapors) in the inhaled and exhaled gas.

5. Recovery from anesthesia or awakening- no less important stage than induction anesthesia and maintenance of anesthesia. During the recovery from anesthesia, reflexes are restored in patients, but gradually, and for some time they may be inadequate. Associated with this is the occurrence of a number of complications of anesthesia, which forces anesthesiologists to continue monitoring the patient even after the end of the operation.

At the end of the operation, before extubation, the anesthesiologist should check the reliability of hemostasis in the oral cavity, good fixation of tampons, protective plates, splints, etc., in order to avoid airway obstruction and aspiration complications.

The postoperative period for dental patients is dangerous with extensive edema, infiltrates in areas where it is dangerous due to impaired airway patency. This is the subject of special attention of the anesthesiologist, as well as the issue of oral care.

Currently, neuroleptanalgesia (NLA) is widely used.) - a type of combined general anestezin, in which drugs are used that cause neurolepsy and analgesia. The method is especially indicated in pediatric surgery. Neuroleptanalgesia(Greek neuron nerve + lepsis grasping, attack + Greek negative prefix ana- + algos pain) is a combined method of intravenous general anesthesia, in which the patient is conscious, but does not experience emotions (neurolepsy) and pain (analgesia). Due to this, protective reflexes of the sympathetic system are turned off and the need for oxygen in tissues decreases. The advantages of neuroleptanalgesia also include: a large breadth of therapeutic action, low toxicity and suppression of the gag reflex.

The most widespread are three types of NLA:

using fentanyl, droperidol. nitrous oxide with oxygen, mnorelaxants, mechanical ventilation (artificial ventilation of the lungs);

as an aid in inhalation general anesthesia;

in combination with local anesthesia while maintaining spontaneous breathing.

A relatively new type of general anesthesia is combined electroanesthesia., in which generators of pulsed, sinusoidal current, etc. are used. The advantages of this anesthesia are as follows:

A narcotic state can be caused by excluding all narcotic drugs from the combined anesthesia scheme.

Electric current has no direct toxic effect and affects only the central nervous system.

Anesthesia is simple, anesthesia can be interrupted at any time, there is no cumulation, the method is explosion-proof and economical.

However, regardless of the applied current and apparatus, the method has a significant drawback: the current causes pain at the site of its passage, and therefore, medications must be used to introduce electroanesthesia. Therefore, it is not widely used in the practice of a dentist.

When providing general anesthesia, the anesthesiologist and surgeon should take into account the features of the most important systems of the child's body, which differ from those in adults, the anatomical, physiological and psychological characteristics of children of different ages, the specifics of surgical interventions in the maxillofacial region and oral cavity. The volume and size of various organs and anatomical formations in a child is much smaller than in adults, which requires special tools and equipment. The idea that children (especially younger children) are less sensitive to pain and mental trauma is wrong. They require adequate anesthesia.

In order to avoid surprises during anesthesia associated with individual hypersensitivity or intolerance to any drugs (especially narcotic drugs), the doctor must carefully find out the child's history from the parents, clarify whether he has unusual reactions to taking various drugs, foods, severe allergic status, the child's tendency to faint, loss of consciousness in response to factors such as pain, fear.

The family history is also important: data on the intolerance of the next of kin to any drugs, since it is possible that the intolerance of pharmacological agents was genetically transmitted to the child. It is important to find out if the child is registered with other specialists at the dispensary. A clear understanding of the general condition of the child and the vital functions of the body determines the correct choice of the type and method of anesthesia and is the prevention of possible complications during local and general anesthesia.

Respiratory system in young children has a number of features. Narrow upper airways are easily injured and prone to mucosal edema; hypertrophied palatine tonsils, hyperglossia and increased secretion of mucous glands - all this increases the threat of violation of their patency. Excursion of the chest in young children is reduced as a result of limited mobility of the diaphragm, ribs and sternum. The aerodynamic resistance of the respiratory tract, as well as the need for oxygen consumption, are increased. In this regard, the respiratory system of even a healthy small child is significantly strained to ensure normal gas exchange, and minimal respiratory disturbances lead to respiratory failure. Accumulation of secretions in the tracheobronchial tree, mucosal edema, increased resistance in the "lung - anesthetic apparatus" system, painful hypoventilation cause severe respiratory failure.

In newborns, the entrance to the trachea between the vocal cords is about 14 mm, and the diameter of the trachea in the area of ​​the cricoid cartilage is 4 mm. The lungs of a small child are more full-blooded and less elastic, the functioning alveolar surface is three times smaller than in adults, in relation to body weight. The ribs in infants are horizontal, the intercostal and auxiliary respiratory muscles are poorly developed, the volume of the abdominal cavity is enlarged, the intestines often contain a lot of gases, resulting in increased intra-abdominal pressure and high standing of the diaphragm. All this determines the functional features of the lung system of young children, namely, an increased need for oxygen (by 25-30%) with an increase in body temperature. This condition is compensated by an increase in the frequency of breaths, shallow breathing, which, in turn, leads to an incorrect ratio of inhalation and exhalation.

Anatomical and physiological features of the child's respiratory tract, as well as the frequency of a hyperergic reaction in response to an irritant, lead to one of the most formidable complications - the rapid development of edema. And if in an adult it causes irritation in the throat, then in a small child - laryngospasm. So thickening of the mucous membrane of the respiratory tract in newborns by 1 mm reduces their lumen by 75%, and in an adult - only by 19 %. Therefore, any factors that can disrupt breathing are threatening from possible serious violations of ventilation, gas exchange and the entire homeostasis of the child, especially at an early age.

The cardiovascular system the baby is more stable than the respiratory. Anatomical features provide its functional balance.

The child's cardiovascular system does not react as sharply to stressful situations as the respiratory system. True, the heart muscle is more prone to infectious diseases, but the full recovery of myocardial function in children occurs more often and faster than in adults. The predominance of sympathetic innervation causes a frequent pulse and a tendency to tachycardia in young children. So, the pulse in young children increases significantly when they cry, strain.

Young children have lower blood pressure than adults. This is due to the large lumen of the vessels, the elasticity of their walls and the lower pumping capacity of the heart. The complex regulation of vascular tone in a young child is associated with insufficient blocking action of the vagus nerve. This, together with the centralization of blood circulation characteristic of young children (almost 2/3 of the capillary bed normally does not participate in circulation), leads to frequent fluctuations in pulse and blood pressure. Increased oxygen consumption and higher, compared with adults, the level of metabolism predetermine the intensification of some hemodynamic processes. In a child, the volume of blood in milliliters per 1 kg of body weight is 20-30% more than in adults; blood flow velocity is 2 times greater, cardiac output and stroke volume are also relatively greater than in adults.

The surgeon must be aware that the young child is very sensitive to blood loss. Hyperhydration due to the threat of cardiac dysfunction, swelling of the brain and lungs in him is just as dangerous as severe hypovolemia. If the blood loss is more than 12-15 % BCC (volume of circulating blood), it is advisable to restore it with the help of hemodilution (60-70% with blood and 30-40% with liquid).

Nervous system The child has a number of characteristics. One of the main ones is that the cerebral cortex does not yet show the necessary regulatory influence on the lower parts of the nervous system, and therefore most of the reflexes of a young child are carried out through the subcortical parts of the central nervous system and have a reflex-stereotypical and athetosis-like character.

This leads to such functional disorders:

In young children, the response to many external and internal stimuli of a different nature is relatively stereotypical - convulsions. Their tendency to convulsive reactions is explained by a higher metabolism and greater hydrophilicity of brain tissues.

Diffuse and generalized reaction of the nervous system in response to a variety of stimuli, in particular pain. Therefore, a child, even after minor stressful influences (hypothermia, minor pain, minor trauma, etc.), may have a violent reaction with hyperthermic and convulsive syndromes, a sharp change in breathing and other disorders.

3. Compensatory reactions in newborns and young children quickly fade away. Under the influence of various irritants in children of the first year of life, "overwork" of the respiratory and vasomotor centers quickly sets in.

4. Due to the peculiarities of the autonomic nervous system, the cardiovascular system of a child at the time of birth and at an early age is much better regulated than the respiratory system. In a variety of critical, stressful and other situations, a child's breathing is disturbed much faster and more significantly than the functions of other systems.

Many doctors have the impression that there is no pronounced pain sensitivity in young children due to the underdeveloped and differentiated cerebral cortex. It is not right. Children have a pronounced, although not typical for adults, reaction to pain: a rapid violation of respiratory function, depletion of compensatory mechanisms, a latent trace reaction. It is known that children who underwent traumatic manipulations without adequate anesthesia even at an early age had night terrors, stuttering, etc., much more often. Therefore, the lengthening of the frenulum of the tongue, the surgical treatment of wounds of small size and depth, the removal of temporary teeth, carried out without anesthesia, are:

inhumane, non-medical attitude towards a defenseless patient;

the risk of receiving unforeseen, up to irreparable, complications;

the lowest assessment of the theoretical training and qualifications of a doctor.

The fact of ignorance of the anatomical, physiological and functional characteristics of the child's body does not justify such actions.

Metabolism. The basal metabolism in children is significantly increased. In this regard, they are administered a variety of therapeutic substances in relatively large doses than adults. A large expenditure of energy requires adequate replenishment. Therefore, infusion therapy with the introduction of the required amount of protein, electrolytes is the most important task in intensive care. Young children require more nucleic acids than adults. With a lack of carbohydrates or their significant loss, their fat depot quickly decreases. Children are characterized by hydrolability - rapid loss and replenishment of water. The younger the child, the lower the threshold of endurance to oxygen starvation.

urinary system against the background of increased water exchange, it functions to the maximum, on the verge of the possible. In young children, there is a marked tendency to metabolic acidosis. They are more prone to sodium retention and edema formation. Excessive administration of chlorine leads to hypersalemia and salt intoxication. Conversely, the consequences of vomiting and diarrhea are the loss of chlorine, a decrease in the osmotic pressure of the plasma, and the development of exsicosis.

Thermoregulation. It is important for the surgeon to know the features of thermoregulation in young children. Their heat production lags behind heat transfer (a smaller ratio of muscle tissue mass to body surface). Subcutaneous adipose tissue, retaining heat, is not enough, the vascular center does not yet regulate heat transfer by constriction and expansion of blood vessels. In this regard, the body temperature of the child significantly depends on the temperature of the external environment. Cooling a small patient leads to severe metabolic and hemodynamic disturbances. The child cannot compensate for the loss of heat by increased muscular activity, and he has very few energy reserves. In this regard, when conducting general anesthesia in young children, one of the most important tasks is to create conditions for maintaining normal body temperature.

In a hospital setting, all modern achievements in general anesthesiology can be successfully used and adapted to this contingent of patients.

As for the conditions of the clinic, there has long been no doubt about the appropriateness and prospects for the use of anesthesia in pediatric dental practice.

Anesthesia allows for the treatment of non-contact and low-contact children, creates comfort for the patient and convenience for the doctor, reduces the time of treatment and improves its quality.

However, the introduction of general anesthesia in polyclinics is associated with objective difficulties due to the lack of anesthesiologists and dentists, specially trained to work in the pediatric dental department, and some other organizational problems.

At this stage of development of dental care for children, the centralization of the anesthesia service is more justified and safe.

The anesthesiologist stands out from among not only sufficiently experienced specialists, but his specialization in anesthesiology in dentistry is desirable.

Features of anesthesia in outpatient clinicsconditions:

unusual sitting position of the patient, which makes it difficult for the anesthesiologist to observe him, standing behind the patient;

work in the mouth, creating the preconditions for mechanical obstruction of the airways - pushing in a tampon located in the throat area,

tongue fall,

drooping of the lower jaw,

flow of saliva and blood,

foreign bodies in the mouth in the form of cotton wool, filling material, tooth dust, extracted teeth, etc.),

nasal mask, which is used for mask anesthesia with the possible introduction of a short endotracheal tube under the mask into the nasal passage if the child has a cleft palate, adenoid growths and other causes that change the nature of breathing.,

during treatment, the anesthesiologist must correctly fix the h/h to ensure free spontaneous breathing. N / h is held in the extended position, avoiding its lateral shifts. The displacement of the tongue and the mandible occurs not only from the relaxation of the masticatory muscles under the influence of the drug, but also from various manipulations of the dentist, especially during the extraction of the teeth of the mandible, when significant pressure develops on it. When treating lower molars, the dentist often presses the tongue back and to the side with cotton rolls or a mirror, which can adversely affect breathing.

A dentist must be a highly qualified therapist who has mastered the methods of endodontics, who also knows how to extract teeth and is able to provide emergency and complete surgical care for acute purulent inflammatory processes and trauma.

The working conditions of the dentist are also unusual:

the diagnosis of diseases is difficult due to the lack of a patient's reaction under anesthesia,

the usual multi-stage treatment is excluded, one-session methods of treatment are more often used,

it is difficult to evaluate the effectiveness of endodontic measures,

there is no possibility of X-ray control at the stages of treatment.

A specially trained and permanently working dentist gradually overcomes these difficulties in his work.

nurse anesthetist

helps in conducting anesthesia and provides monitoring of the child's condition, which is recorded in the anesthesia card.

supervises the child in the post-anesthetic period,

timely prepares the necessary tools and medicines,

prepares filling materials in a quality and timely manner.

A dental nurse, working constantly with one doctor, masters well not only the sequence of medical manipulations, but also the technique and features of treatment inherent in this doctor. She has a well-prepared workplace with convenient placement of everything she needs on the table.

All members of the team must be trained and quickly register the slightest changes in the child's condition: violation of spontaneous breathing, discoloration of the mucous membrane, salivation, deepening of anesthesia or untimely awakening of the patient, etc.

A coordinated tactic must be developed by all members of the team for the rapid correction of these short-term violations. This is possible only if there is an absolute mutual understanding and cooperation of the personnel constantly working together. This significantly reduces the risk of treating dental diseases under anesthesia. All team members must be proficient in prehospital cardiopulmonary resuscitation.

Indications for outpatient anesthesia in a hundredmatology can be generalized into three groups.

I. Indications due to the health group and psycho-emotional state of the child:

malformations and diseases of the central nervous system;

constitutional anomalies with presumed intolerance to local anesthetics;

psycho-emotional excitability, fear of treatment at the dentist:

a) in healthy children;

b) in children with concomitant diseases in the compensation stage, in particular from the group of cardiovascular diseases and respiratory diseases with an allergic component.

II. Indications due to the age of the child (all operations in children under 3 years).

III. Indications due to dental diseases:

Emergency conditions in children associated with acute odontogenic and non-odontogenic inflammatory processes of the oral cavity and maxillofacial area (treatment of periostitis, lymphadenitis, abscesses), especially at an early age.

Planned sanation operations for chronic periodontitis, radicular and follicular cysts of the jaws, lengthening of short frenulums of the tongue and lips.

inadequate local anesthesia.

Contraindications to anesthesia in a polyclinic:

severe or decompensated forms of common concomitant heart diseases, endocrine diseases, in particular diabetes mellitus, rickets, hepatitis, nephritis, etc. Children with this status practically do not go to the clinic, since, due to the severity of their background disease, they need treatment in specialized hospitals . These contraindications should be kept in mind by dentists working in somatic hospitals.

More common contraindications for outpatient treatment under anesthesia are:

acute infectious diseases, including acute herpetic stomatitis, SARS (the interval between the disease and treatment under anesthesia should be at least 2 weeks);

anomalies of the constitution, accompanied by hypertrophy of the thymus gland;

difficulty or impossibility of nasal breathing due to the curvature of the nasal septum, adenoid growths, chronic rhinitis, etc. (for inhalation anesthesia);

children with a full stomach (recently eaten). If it is necessary to provide them with emergency dental care, they must wait at least 4 hours after eating. If the intervention cannot be delayed, then the removal of gastric contents is carried out through a gastric tube.

It is important to consider the localization of the pathological process. Outpatient operations in the area of ​​the pharynx, maxillary-lingual groove are fraught with aspiration and dislocation (displacement of the tongue, tampon, etc.) complications. Therefore, special attention is needed when performing them or refusing to operate on an outpatient basis.

When planning a certain amount of therapeutic measures for a given patient, it is necessary to focus on the duration of treatment, which should not exceed an average of 40 minutes, with an allowable limit of lengthening the anesthesia time up to 60 minutes. These terms are due to the fact that the duration of post-anesthetic restoration of the adequacy of the child's behavior is directly proportional to the duration of anesthesia. At the same time, for outpatient conditions, it is important to ensure the possibility of a rhythmic flow of patients so that observations of one patient do not overlap with the treatment of the next.

In 40 minutes of anesthesia time, a large amount of work can be done, taking into account the calm behavior of the child, work without interruptions even for spitting, the high qualification of the doctor and good dental equipment.

Polyclinic treatment conditions, the need to quickly restore the adequacy of the child's behavior and the ability to let him go home require maximum relief from polyclinic anesthesia. That's why from a large arsenal of types and methods of anesthesia forpolyclinics are selected such that not only provideeffective anesthesia, amnesia, relaxation of the muscles of the jaw-facial area, but also well controlled, accompanied byminimal discomfort for the patient, do not giveschimi expressed oppression in the post-narcotic period. The adequacy of the behavior of a child leaving the clinic after treatment should be such as to be absolutely sure that there are no complications or adverse reactions in the late post-anesthesia period.

The choice of anesthesia is decided only by the anesthesiologist, who will carry it out depending on his personal training.

In a polyclinic, preference is given to mask anesthesia with a mixture of halothane, nitrous oxide and oxygen. However, substances that the anesthetist injects intravenously or intramuscularly have become widely used in outpatient settings. Depending on the type of intervention, the age of the child, where the intervention will be performed (in the oral cavity or outside it), and on many other reasons (equipment of the anesthesiology service of the polyclinic, choice of medications, experience of the anesthetist and dental surgeon), the type of anesthesia is selected because each of them has its own advantages and disadvantages. So, intravenous administration of a monoanesthetic, for example, ketamine, ketalar, calypsol, is very convenient: the child enters anesthesia quickly and calmly, expensive equipment that is used for inhalation anesthesia is not needed, there are no hypotensive and emetic reactions, it is possible to extend the time of anesthesia for due to the repeated administration of the anesthetic at a dose of 1/4-1/2 from the primary one. Recently, recofol (propofol), a fast-acting intravenous anesthetic, has been widely used. Compared to other similar drugs, propofol reduces the time to recovery from anesthesia and the need for antiemetics after it.

Their disadvantages are: the threat of overdose; individual intolerance to the drug due to the lack of effective targeted antidotes; the inability to quickly withdraw from anesthesia if necessary; retraction of the tongue with the occurrence of asphyxia and shortness of breath. If all of the listed shortcomings, except for the last one, are the direct concern of the anesthetist, then the retraction of the tongue is not only a threat, but also a great inconvenience for the dental surgeon. In this case, during manipulations in the oral cavity, the assistant must constantly monitor the position of the tongue stitched with a ligature or fixed by the instrument, as well as the operation of the saliva ejector to prevent aspiration of blood, saliva, cyst contents, obturation with fragments of teeth, bones, needle tips or parts of other instruments. This, of course, makes it difficult to carry out relatively long operations in the oral cavity.

Inhalation anesthesia, if we exclude a number of disadvantages of intravenous and intramuscular injection of anesthetics, has the following advantages:

1) during tracheal intubation, reliable artificial ventilation of the lungs is carried out, providing, even in comparison with mask anesthesia, more adequate gas exchange;

there is a reliable protection of the respiratory tract from the flow of blood and saliva, which allows you to safely operate in the oral cavity;

it is easy to manage anesthesia, its depth, to provide a relatively quick withdrawal from anesthesia.

These advantages, however, do not reduce the disadvantages of inhalation anesthesia, the main conditions for which are:

the use of expensive devices, devices and instruments of general anesthesia;

the need for long-term monitoring of the child's condition in the postoperative period;

3) the possibility of edema of the subglottic space in children after endotracheal anesthesia and subsequent complications in connection with this.

It is more correct to use endotracheal anesthesia in outpatient dentistry in the conditions of the so-called one-day hospital or day hospital. Otherwise, if the polyclinic does not have the conditions to allocate a separate operating day, and the doctors have the opportunity to monitor the state of the child's body for the required amount of time, combined general anesthesia with muscle relaxants and tracheal intubation on an outpatient basis increases the risk of complications.

After the end of the operation and the withdrawal of the child from anesthesia, the correctness of the surgeon's actions becomes very important. The effectiveness and sequence of such stages and manipulations are fundamentally important:

when performing surgical intervention in the oral cavity, it is necessary to ensure thorough hemostasis in the wound after the end of the operation. Without this, it is not advisable to carry out measures to bring the child out of anesthesia;

it is necessary to carefully and carefully examine the surgical field and oral cavity and make sure that there are no pieces of teeth, bones, needles, instruments, swabs, rubber pads, drainage outside the wound, remnants of ligature wire, etc.;

when performing operations on the soft palate, palatoglossal and palatopharyngeal arches, in the region of the root of the tongue, the assistant fixes the wide-open mouth with a mouth expander, the excessive action of which can lead to anterior dislocation of the lower jaw, dislocation (more often) of temporary teeth in a mixed bite - such a possibility must be provided;

during laryngoscopy, there may be damage to the frontal group of teeth in / h, their traumatic removal, which does not exclude the possibility of obstructive asphyxia when withdrawing from anesthesia;

when saliva, mucus, blood clots accumulate in the oral cavity, it is necessary to remove them with a saliva ejector, since during this period the irritating effect of any foreign bodies can provoke vomiting, laryngospasm and other complications.

Modern surgical intervention is impossible to imagine without adequate anesthesia. The painlessness of surgical operations is currently provided by a whole branch of medical science called anesthesiology. This science deals not only with the methods of anesthesia, but also with the methods of controlling the functions of the body in a critical state, which is modern anesthesia. In the arsenal of a modern anesthesiologist who comes to the aid of a surgeon, a large number of techniques - from relatively simple (local anesthesia) to the most complex methods of controlling body functions (hypothermia, controlled hypotension, cardiopulmonary bypass).

But it was not always so. For several centuries, stupefying tinctures were offered as a means of combating pain, patients were stunned or even strangled, and nerve trunks were pulled with tourniquets. Another way was to reduce the duration of surgery (for example, N. I. Pirogov removed stones from the bladder in less than 2 minutes). But before the discovery of anesthesia, abdominal operations were inaccessible to surgeons.

The era of modern surgery began in 1846, when the anesthetic properties of ether vapor were discovered by chemist C. T. Jackson and dentist W. T. G. Morton, and the first extraction of a tooth under general anesthesia was performed. Somewhat later, surgeon M. Warren performed the world's first operation (removal of a neck tumor) under inhalation anesthesia using ether. In Russia, the introduction of anesthesia techniques was facilitated by the work of F. I. Inozemtsev and N. I. Pirogov. The works of the latter (he made about 10 thousand anesthesias during the Crimean War) played an exceptionally large role. Since that time, the technique of anesthesia has become much more complicated and improved, opening up opportunities for the surgeon to perform unusually complex interventions. But the question of what is anesthesia sleep and what are the mechanisms of its occurrence still remains open.

A large number of theories have been put forward to explain the phenomenon of anesthesia, many of which have not stood the test of time and are of purely historical interest. These are, for example:

1) Bernard's coagulation theory(according to his ideas, the drugs used for induction into anesthesia caused coagulation of the protoplasm of neurons and a change in their metabolism);

2) lipoid theory(according to her ideas, narcotics dissolve the lipid substances of the membranes of nerve cells and, penetrating inside, cause a change in their metabolism);

3) protein theory(narcotic substances bind to enzyme proteins of nerve cells and cause a violation of oxidative processes in them);

4) adsorption theory(in the light of this theory, drug molecules are adsorbed on the surface of cells and cause a change in the properties of membranes and, consequently, the physiology of the nervous tissue);

5) theory of inert gases;

6) neurophysiological theory(most fully answers all the questions of researchers, explains the development of anesthesia under the influence of certain drugs by phase changes in the activity of the reticular formation, which leads to inhibition of the central nervous system).

In parallel, studies were conducted to improve the methods of local anesthesia. The founder and main promoter of this method of anesthesia was A. V. Vishnevsky, whose fundamental works on this issue are still unsurpassed.

anesthesia- this is an artificially induced deep sleep with the exclusion of consciousness, analgesia, inhibition of reflexes and muscle relaxation. It becomes clear that modern anesthetic management of surgical intervention, or anesthesia, is the most complex multicomponent procedure, which includes:

1) narcotic sleep (caused by drugs for anesthesia). Includes:

a) turning off consciousness - complete retrograde amnesia (events that happened to the patient during anesthesia are recorded in the memory);

b) decrease in sensitivity (paresthesia, hypesthesia, anesthesia);

c) proper analgesia;

2) neurovegetative blockade. It is necessary to stabilize the reactions of the autonomic nervous system to surgical intervention, since the autonomics are not largely controlled by the central nervous system and are not regulated by anesthetic drugs. Therefore, this component of anesthesia is carried out by using peripheral effectors of the autonomic nervous system - anticholinergics, adrenoblockers, ganglionic blockers;

3) muscle relaxation. Its use is applicable only for endotracheal anesthesia with controlled breathing, but it is necessary for operations on the gastrointestinal tract and major traumatic interventions;

4) maintaining an adequate state of vital functions: gas exchange (achieved by an accurate calculation of the ratio of the gas mixture inhaled by the patient), blood circulation, normal systemic and organ blood flow. You can monitor the state of blood flow by the value of blood pressure, as well as (indirectly) by the amount of urine excreted per hour (urine debit-hour). It should not be lower than 50 ml/h. Maintaining blood flow at an adequate level is achieved by blood dilution - hemodilution - by constant intravenous infusion of saline solutions under the control of central venous pressure (normal value is 60 mm of water column);

5) maintaining metabolic processes at the proper level. It is necessary to take into account how much heat the patient loses during the operation, and to conduct adequate warming or, conversely, cooling the patient.

Indications for surgical intervention under general anesthesia determined by the severity of the planned intervention and the patient's condition. The more severe the patient's condition and the more extensive the intervention, the more indications for anesthesia. Minor interventions in a relatively satisfactory condition of the patient are carried out under local anesthesia.

Classification of anesthesia along the route of drug administration into the body.

1. Inhalation (narcotic substance in vapor form is supplied to the patient's respiratory system and diffuses through the alveoli into the blood):

1) mask;

2) endotracheal.

2. Intravenous.

3. Combined (as a rule, induction anesthesia with an intravenously administered drug, followed by the connection of inhalation anesthesia).

First stage

Analgesia (hypnotic phase, round anesthesia). Clinically, this stage is manifested by a gradual depression of the patient's consciousness, which, however, does not completely disappear in this phase. The patient's speech gradually becomes incoherent. The patient's skin turns red. Pulse and respiration slightly increased. The pupils are the same size as before the operation, they react to light. The most important change in this stage concerns pain sensitivity, which practically disappears. The remaining types of sensitivity are preserved. In this stage, surgical interventions, as a rule, are not performed, but small superficial incisions and reduction of dislocations can be performed.

Second stage

Excitation stage. In this stage, the patient loses consciousness, but there is an increase in motor and autonomic activity. The patient is not accountable for his actions. His behavior can be compared with the behavior of a person who is in a state of extreme intoxication. The patient's face turns red, all muscles tense up, neck veins swell. On the part of the respiratory system, there is a sharp increase in breathing, there may be a short-term stop due to hyperventilation. Increased secretion of the salivary and bronchial glands. Blood pressure and pulse rate rise. Due to the increased gag reflex, vomiting may occur.

Often, patients experience involuntary urination. Pupils in this stage dilate, their reaction to light is preserved. The duration of this stage during ether anesthesia can reach 12 minutes, with the most pronounced excitation in patients who have been abusing alcohol for a long time and drug addicts. These categories of patients need fixation. In children and women, this stage is practically not expressed. With the deepening of anesthesia, the patient gradually calms down, the next stage of anesthesia begins.

Third stage

Anesthesia sleep stage (surgical). It is at this stage that all surgical interventions are carried out. Depending on the depth of anesthesia, there are several levels of anesthesia sleep. All of them completely lack consciousness, but the systemic reactions of the body have differences. In connection with the special importance of this stage of anesthesia for surgery, it is advisable to know all its levels.

signs first level, or stages of preserved reflexes.

1. Only superficial reflexes are absent, laryngeal and corneal reflexes are preserved.

2. Breathing is calm.

4. The pupils are somewhat narrowed, the reaction to light is lively.

5. Eyeballs move smoothly.

6. Skeletal muscles are in good shape, therefore, in the absence of muscle relaxants, operations in the abdominal cavity at this level are not performed.

Second level characterized by the following manifestations.

1. Weaken and then completely disappear reflexes (laryngeal-pharyngeal and corneal).

2. Breathing is calm.

3. Pulse and blood pressure at the preanesthetic level.

4. Pupils gradually dilate, in parallel with this, their reaction to light weakens.

5. There is no movement of the eyeballs, the pupils are set centrally.

6. Relaxation of skeletal muscles begins.

Third level has the following clinical features.

1. There are no reflexes.

2. Breathing is carried out only due to movements of the diaphragm, therefore shallow and rapid.

3. Blood pressure decreases, pulse rate increases.

4. The pupils dilate, and their reaction to the usual light stimulus is practically absent.

5. Skeletal muscles (including intercostal) are completely relaxed. As a result of this, the jaw often droops, the retraction of the tongue and respiratory arrest can pass, so the anesthesiologist always brings the jaw forward in this period.

6. The transition of the patient to this level of anesthesia is dangerous for his life, therefore, if such a situation arises, it is necessary to adjust the dose of the anesthetic.

Fourth level previously called agonal, since the state of the organism at this level is, in fact, critical. At any moment, due to paralysis of breathing or cessation of blood circulation, death can occur. The patient needs a complex of resuscitation measures. The deepening of anesthesia at this stage is an indicator of the low qualification of the anesthesiologist.

1. All reflexes are absent, there is no pupil reaction to light.

2. The pupils are maximally dilated.

3. Breathing is superficial, sharply accelerated.

4. Tachycardia, thready pulse, blood pressure is significantly reduced, may not be detected.

5. There is no muscle tone.

Fourth stage

Occurs after the cessation of the drug supply. The clinical manifestations of this stage correspond to the reverse development of those during immersion in anesthesia. But they, as a rule, proceed more quickly and are not so pronounced.

Mask anesthesia. In this type of anesthesia, the anesthetic in the gaseous state is supplied to the patient's respiratory tract through a mask of a special design. The patient can breathe on his own, or the gas mixture is supplied under pressure. When carrying out inhalation mask anesthesia, it is necessary to take care of the constant airway patency. For this, there are several methods.

2. Removal of the lower jaw forward (prevents the retraction of the tongue).

3. Establishment of the oropharyngeal or nasopharyngeal duct.

Mask anesthesia is quite difficult to tolerate by patients, so it is not used so often - for minor surgical interventions that do not require muscle relaxation.

Advantages endotracheal anesthesia. This is to ensure constant stable ventilation of the lungs and the prevention of obstruction of the airways by aspirate. The disadvantage is the higher complexity of this procedure (in the presence of an experienced anesthesiologist, this factor does not really matter).

These qualities of endotracheal anesthesia determine the scope of its application.

1. Operations with an increased risk of aspiration.

2. Operations with the use of muscle relaxants, especially thoracic ones, in which there may often be a need for separate ventilation of the lungs, which is achieved by using double-lumen endotracheal tubes.

3. Operations on the head and neck.

4. Operations with turning the body on its side or stomach (urological, etc.), in which spontaneous breathing becomes very difficult.

5. Long-term surgical interventions.

In modern surgery, it is difficult to do without the use of muscle relaxants.

These drugs are used for anesthesia during intubated trachea, abdominal operations, especially during surgical interventions on the lungs (tracheal intubation with a double-lumen tube allows ventilation of only one lung). They have the ability to potentiate the action of other components of anesthesia, so when they are used together, the concentration of the anesthetic can be reduced. In addition to anesthesia, they are used in the treatment of tetanus, emergency therapy for laryngospasm.

For combined anesthesia, several drugs are used simultaneously. This is either several drugs for inhalation anesthesia, or a combination of intravenous and inhalation anesthesia, or the use of an anesthetic and a muscle relaxant (when reducing dislocations).

In combination with anesthesia, special methods of influencing the body are also used - controlled hypotension and controlled hypothermia. With the help of controlled hypotension, a decrease in tissue perfusion is achieved, including in the area of ​​surgical intervention, which leads to minimization of blood loss. Controlled hypothermia or lowering the temperature of either the whole body or part of it leads to a decrease in tissue oxygen demand, which allows for long-term interventions with limited or switched off blood supply.

Special forms of anesthesia are neuroleptanalgesia- the use of a combination of an antipsychotic (droperidol) and an anesthetic drug (fentanyl) for pain relief - and ataralgesia - the use of a tranquilizer and an anesthetic drug for pain relief. These methods can be used for small interventions.

Electroanalgesia- a special effect on the cerebral cortex with an electric current, which leads to synchronization of the electrical activity of the cortex in ? -rhythm, which is also formed during anesthesia.

Anesthesia requires the presence of a specialist anesthesiologist. This is a complex procedure and a very serious interference in the functioning of the body. Properly performed anesthesia, as a rule, is not accompanied by complications, but they still happen even with experienced anesthesiologists.

Quantity anesthesia complications extremely large.

1. Laryngitis, tracheobronchitis.

2. Obstruction of the respiratory tract - retraction of the tongue, entry of teeth, prostheses into the respiratory tract.

3. Lung atelectasis.

4. Pneumonia.

5. Violations in the activity of the cardiovascular system: collapse, tachycardia, other cardiac arrhythmias up to fibrillation and circulatory arrest.

6. Traumatic complications during intubation (wounds of the larynx, pharynx, trachea).

7. Violations of the motor activity of the gastrointestinal tract: nausea, vomiting, regurgitation, aspiration, intestinal paresis.

8. Urinary retention.

9. Hypothermia.

Currently, there are no theories of anesthesia that would clearly define the narcotic mechanism of action of anesthetics. Among the available theories of anesthesia, the most significant are the following. Drugs can cause specific changes in all organs and systems. During the period when the body is saturated with a narcotic analgesic, there is a certain staging in the change in consciousness, respiration and blood circulation of the patient. Therefore, there are stages that characterize the depth of anesthesia. These stages manifest themselves especially clearly during ether anesthesia. There are 4 stages:

1) analgesia;

2) excitement;

3) surgical stage, subdivided into 4 levels;

4) stage of awakening.

Stage of analgesia

The patient is conscious, but some lethargy is noted, he is dozing, answers questions in monosyllables. Superficial and pain sensitivity are absent, but as for tactile and thermal sensitivity, they are preserved. In this stage, short-term surgical interventions are performed, such as opening phlegmon, abscesses, diagnostic studies, etc. The stage is short-term, lasting 3-4 minutes.

Excitation stage

In this stage, the centers of the cerebral cortex are inhibited, and the subcortical centers at this time are in a state of excitation. At the same time, the patient's consciousness is completely absent, pronounced motor and speech excitation is noted. Patients begin to scream, make attempts to get up from the operating table. Hyperemia of the skin is noted, the pulse becomes frequent, systolic blood pressure rises. The pupil of the eye becomes wide, but the reaction to light persists, lacrimation is noted. Often there is a cough, increased bronchial secretion, sometimes vomiting. Surgical intervention against the background of excitation cannot be performed. During this period, you should continue to saturate the body with a narcotic to enhance anesthesia. The duration of the stage depends on the general condition of the patient and the experience of the anesthesiologist. Typically, the duration of excitation is 7-15 minutes.

Surgical stage

With the onset of this stage of anesthesia, the patient calms down, breathing becomes calm and even, heart rate and blood pressure approach normal. During this period, surgical interventions are possible. Depending on the depth of anesthesia, 4 levels and stage III of anesthesia are distinguished. First level: the patient is calm, the number of respiratory movements, the number of heartbeats and blood pressure are approaching the initial values. The pupil gradually begins to narrow, its reaction to light is preserved. There is a smooth movement of the eyeballs, an eccentric arrangement. The corneal and pharyngeal-laryngeal reflexes were preserved. Muscle tone is preserved, therefore abdominal operations at this level are not performed. Second level: the movement of the eyeballs is stopped, they are fixed in a central position. The pupils dilate, and their reaction to light weakens. The activity of the corneal and pharyngeal-laryngeal reflexes begins to weaken with a gradual disappearance towards the end of the second level. Respiratory movements are calm and even. Values ​​of arterial pressure and pulse acquire normal values. Muscle tone is reduced, which allows for abdominal operations. Anesthesia, as a rule, is carried out in the period of the first and second levels. The third level is characterized as deep anesthesia. At the same time, the pupils of the eyes are dilated with a reaction to a strong light stimulus. As for the corneal reflex, it is absent. Complete relaxation of the skeletal muscles develops, including the intercostal muscles. Due to the latter, respiratory movements become superficial or diaphragmatic. The lower jaw sags, as its muscles relax, the root of the tongue sinks and closes the entrance to the larynx. All of the above leads to respiratory arrest. In order to prevent this complication, the lower jaw is brought forward and held in this position. At this level, tachycardia develops, and the pulse becomes small filling and tension. The level of arterial pressure decreases. Carrying out anesthesia at this level is dangerous for the life of the patient. fourth level; the maximum expansion of the pupil with the absence of its reaction to light, the cornea is dull and dry. Given that paralysis of the intercostal muscles develops, breathing becomes superficial and is carried out by movements of the diaphragm. Tachycardia is characteristic, while the pulse becomes threadlike, frequent and difficult to determine in the periphery, blood pressure is sharply reduced or not detected at all. Anesthesia at the fourth level is life-threatening for the patient, as respiratory and circulatory arrest may occur.

Awakening stage

As soon as the introduction of narcotic drugs stops, their concentration in the blood decreases, and the patient goes through all the stages of anesthesia in reverse order, awakening occurs.

The anesthesiologist takes a direct and often the main role in preparing the patient for anesthesia and surgery. An obligatory moment is the examination of the patient before the operation, but at the same time, not only the underlying disease, for which surgery is to be performed, but also the presence of concomitant diseases, which the anesthesiologist asks in detail, is important. It is necessary to know how the patient was treated for these diseases, the effect of treatment, the duration of treatment, the presence of allergic reactions, the time of the last exacerbation. If the patient undergoes a surgical intervention in a planned manner, then, if necessary, correction of existing concomitant diseases is carried out. Sanitation of the oral cavity is important in the presence of loose and carious teeth, as they can be an additional and undesirable source of infection. The anesthesiologist finds out and evaluates the psychoneurological state of the patient. So, for example, in schizophrenia, the use of hallucinogenic drugs (ketamine) is contraindicated. Surgery during the period of psychosis is contraindicated. In the presence of a neurological deficit, it is preliminarily corrected. Allergic history is of great importance for the anesthesiologist, for this, intolerance to drugs, as well as food, household chemicals, etc. is specified. If the patient has a aggravated allergic anamnesis, not even to medications, during anesthesia, an allergic reaction can develop up to anaphylactic shock. Therefore, desensitizing agents (diphenhydramine, suprastin) are introduced into premedication in large quantities. An important point is the presence of a patient in the past operations and anesthesia. It turns out what the anesthesia was and whether there were any complications. Attention is drawn to the somatic condition of the patient: the shape of the face, the shape and type of the chest, the structure and length of the neck, the severity of subcutaneous fat, the presence of edema. All this is necessary in order to choose the right method of anesthesia and drugs. The first rule for preparing a patient for anesthesia during any operation and when using any anesthesia is the cleansing of the gastrointestinal tract (the stomach is washed through the probe, cleansing enemas are performed). To suppress the psycho-emotional reaction and suppress the activity of the vagus nerve, before surgery, the patient is given medication - premedication. At night, phenazepam is prescribed intramuscularly. Patients with a labile nervous system are prescribed tranquilizers (seduxen, relanium) a day before surgery. 40 minutes before surgery, narcotic analgesics are administered intramuscularly or subcutaneously: 1 ml of a 1–2% solution of promolol or 1 ml of pentozocine (lexir), 2 ml of fentanyl, or 1 ml of 1% morphine. To suppress the function of the vagus nerve and reduce salivation, 0.5 ml of a 0.1% solution of atropine is administered. Immediately before the operation, the oral cavity is examined for the presence of removable teeth and prostheses that are removed.

The advantages of intravenous general anesthesia are the rapid introduction of the patient into anesthesia. With this type of anesthesia, there is no excitement, and the patient quickly falls asleep. But narcotic drugs that are used for intravenous administration create short-term anesthesia, so they cannot be used in their pure form as mononarcosis for long-term operations. Barbiturates - thiopental-sodium and hexenal - are able to quickly induce narcotic sleep, while there is no stage of excitation, and awakening is fast. Clinical pictures of anesthesia conducted by sodium thiopental and hexenal are similar. Geksenal has a less inhibitory effect on the respiratory center. Freshly prepared solutions of barbituric acid derivatives are used. The contents of the vial (1 g of the drug) are dissolved before the onset of anesthesia in 100 ml of isotonic sodium chloride solution (1% solution). The peripheral or central (according to indications) vein is punctured and the prepared solution is slowly injected at a rate of 1 ml for 10–15 s. When the solution was injected in a volume of 3–5 ml, the patient's sensitivity to barbituric acid derivatives is determined within 30 seconds. If no allergic reaction is noted, then continue the introduction of the drug until the surgical stage of anesthesia. From the moment of the onset of narcotic sleep, with a single injection of an anesthetic, the duration of anesthesia is 10-15 minutes. To maintain anesthesia, barbiturates are administered in fractions of 100-200 mg of the drug, up to a total dose of not more than 1 g. During the administration of barbiturates, the nurse keeps a record of the pulse, blood pressure and respiration. The anesthesiologist monitors the state of the pupil, the movement of the eyeballs, the presence of a corneal reflex to determine the level of anesthesia. Anesthesia with barbiturates, especially thiopental-sodium, is characterized by depression of the respiratory center, so the presence of an artificial respiration apparatus is necessary. When respiratory arrest (apnea) occurs, artificial lung ventilation (ALV) is performed using a mask of a breathing apparatus. Rapid administration of thiopental sodium can lead to a decrease in blood pressure and cardiac depression. In this case, the administration of the drug is stopped. In surgery, anesthesia with barbiturates as mononarcosis is used for short-term operations that do not exceed 20 minutes in duration (for example, opening of abscesses, phlegmon, reduction of dislocations, diagnostic manipulations, and reposition of bone fragments). Derivatives of barbituric acid are also used for induction anesthesia. Viadryl (predion for injection) is used at a dose of 15 mg/kg, with a total dose of 1000 mg on average. Viadryl is mainly used in small doses along with nitrous oxide. In high doses, this drug may cause a decrease in blood pressure. A complication of its use is the development of phlebitis and thrombophlebitis. In order to prevent their development, it is recommended to administer the drug slowly into the central vein in the form of a 2.5% solution. Viadryl is used for endoscopic examinations as an introductory type of anesthesia. Propanidide (epontol, sombrevin) is available in ampoules of 10 ml of a 5% solution. The dose of the drug is 7-10 mg / kg, administered intravenously, quickly (the entire dose is 500 mg in 30 seconds). Sleep comes immediately - "at the end of the needle." The duration of anesthesia sleep is 5-6 minutes. Awakening is fast, calm. The use of propanidide causes hyperventilation, which occurs immediately after loss of consciousness. Apnea may sometimes occur. In this case, ventilation should be carried out using a breathing apparatus. The negative side is the possibility of hypoxia formation against the background of the drug administration. It is necessary to control blood pressure and pulse. The drug is used for induction anesthesia in outpatient surgical practice for small operations.

Sodium hydroxybutyrate is administered intravenously very slowly. The average dose is 100–150 mg/kg. The drug creates a superficial anesthesia, so it is often used in combination with other narcotic drugs, such as barbiturates - propanidide. It is often used for induction anesthesia.

Ketamine (ketalar) can be used for intravenous and intramuscular administration. The estimated dose of the drug is 2-5 mg / kg. Ketamine can be used for mononarcosis and for induction anesthesia. The drug causes superficial sleep, stimulates the activity of the cardiovascular system (blood pressure rises, pulse quickens). The introduction of the drug is contraindicated in patients with hypertension. Widely used in shock in patients with hypotension. Side effects of ketamine can be unpleasant hallucinations at the end of anesthesia and upon awakening.

Inhalation anesthesia is carried out with the help of easily evaporating (volatile) liquids - ether, halothane, methoxy-flurane (pentran), trichlorethylene, chloroform or gaseous narcotic substances - nitrous oxide, cyclopropane.

With the endotracheal method of anesthesia, the narcotic substance enters the body from the anesthesia machine through a tube inserted into the trachea. The advantage of the method is that it provides free airway patency and can be used in operations on the neck, face, head, eliminates the possibility of aspiration of vomit, blood; reduces the amount of drug used; improves gas exchange by reducing "dead" space.

Endotracheal anesthesia is indicated for major surgical interventions, it is used as a multicomponent anesthesia with muscle relaxants (combined anesthesia). The total use of several drugs in small doses reduces the toxic effects on the body of each of them. Modern mixed anesthesia is used to provide analgesia, turn off consciousness, relaxation. Analgesia and switching off consciousness are carried out by using one or more narcotic substances - inhaled or non-inhaled. Anesthesia is carried out at the first level of the surgical stage. Muscle relaxation, or relaxation, is achieved by the fractional administration of muscle relaxants.

There are three stages of anesthesia.

1. Introduction to anesthesia. Introductory anesthesia can be carried out with any narcotic substance, against which a rather deep anesthetic sleep occurs without arousal stage. Mostly, barbiturates, fentanyl in combination with sombrevin, milled with sombrevin are used. Sodium thiopental is also often used. The drugs are used in the form of a 1% solution, they are administered intravenously at a dose of 400–500 mg. Against the background of induction anesthesia, muscle relaxants are administered and tracheal intubation is performed.

2. Maintenance of anesthesia. To maintain general anesthesia, you can use any narcotic that can protect the body from surgical trauma (halothane, cyclopropane, nitrous oxide with oxygen), as well as neuroleptanalgesia. Anesthesia is maintained at the first and second levels of the surgical stage, and muscle relaxants are administered to eliminate muscle tension, which cause myoplegia of all skeletal muscle groups, including respiratory ones. Therefore, the main condition for the modern combined method of anesthesia is mechanical ventilation, which is carried out by rhythmically squeezing a bag or fur, or using an artificial respiration apparatus.

Recently, the most widespread neuroleptanalgesia. With this method, nitrous oxide with oxygen, fentanyl, droperidol, muscle relaxants are used for anesthesia.

Introductory anesthesia intravenous. Anesthesia is maintained by inhalation of nitrous oxide with oxygen in a ratio of 2: 1, fractional intravenous administration of fentanyl and droperidol 1-2 ml every 15-20 minutes. With an increase in heart rate, fentanyl is administered, with an increase in blood pressure - droperidol. This type of anesthesia is safer for the patient. Fentanyl enhances pain relief, droperidol suppresses vegetative reactions.

3. Withdrawal from anesthesia. By the end of the operation, the anesthesiologist gradually stops the administration of narcotic substances and muscle relaxants. Consciousness returns to the patient, independent breathing and muscle tone are restored. The criterion for assessing the adequacy of spontaneous breathing are indicators of RO 2 , RCO 2 , pH. After awakening, restoration of spontaneous breathing and skeletal muscle tone, the anesthesiologist can extubate the patient and transport him for further observation in the recovery room.

During general anesthesia, the main parameters of hemodynamics are constantly determined and evaluated. Measure blood pressure, pulse rate every 10-15 minutes. In persons with diseases of the cardiovascular system, as well as in thoracic operations, it is necessary to constantly monitor the function of the heart muscle.

Electroencephalographic observation can be used to determine the level of anesthesia. To control lung ventilation and metabolic changes during anesthesia and surgery, it is necessary to study the acid-base state (PO 2 , PCO 2 , pH, BE).

During anesthesia, the nurse maintains an anesthetic chart of the patient, in which she necessarily records the main indicators of homeostasis: pulse rate, blood pressure, central venous pressure, respiratory rate, and ventilator parameters. In this map, all stages of anesthesia and surgery are fixed, the doses of narcotic substances and muscle relaxants are indicated. All drugs used during anesthesia are noted, including transfusion media. The time of all stages of the operation and the administration of drugs is recorded. At the end of the operation, the total number of all the means used is indicated, which is also reflected in the anesthesia card. A record is made of all complications during anesthesia and surgery. The anesthesia card is embedded in the medical history.

Complications during anesthesia may occur due to improper anesthesia technique or the effect of anesthetics on vital organs. One such complication is vomiting. At the beginning of the introduction of anesthesia, vomiting may be associated with the nature of the dominant disease (pyloric stenosis, intestinal obstruction) or with the direct effect of the drug on the vomiting center. Against the background of vomiting, aspiration is dangerous - the entry of gastric contents into the trachea and bronchi. Gastric contents that have a pronounced acid reaction, getting on the vocal cords, and then penetrating into the trachea, can lead to laryngospasm or bronchospasm, resulting in respiratory failure with subsequent hypoxia - this is the so-called Mendelssohn's syndrome, accompanied by cyanosis, bronchospasm, tachycardia.

Regurgitation can become dangerous - passive throwing of gastric contents into the trachea and bronchi. This usually occurs against the background of deep anesthesia using a mask with relaxation of the sphincters and overflow of the stomach or after the introduction of muscle relaxants (before intubation).

Ingestion into the lung during vomiting or regurgitation of acidic gastric contents leads to severe pneumonia, often fatal.

In order to avoid the appearance of vomiting and regurgitation, it is necessary to remove its contents from the stomach with a probe before anesthesia. In patients with peritonitis and intestinal obstruction, the probe is left in the stomach during the entire anesthesia, while a moderate Trendelenburg position is necessary. Before the onset of anesthesia, to prevent regurgitation, you can apply the Selick method - pressure on the cricoid cartilage posteriorly, which causes compression of the esophagus. If vomiting occurs, it is necessary to quickly remove the gastric contents from the oral cavity with a swab and suction; in case of regurgitation, the gastric contents are removed by suction through a catheter inserted into the trachea and bronchi. Vomiting followed by aspiration can occur not only during anesthesia, but also when the patient wakes up. To prevent aspiration in such cases, it is necessary for the patient to take a horizontal or Trendelenburg position, turn his head to the side. The patient should be monitored.

Complications from the respiratory system can occur due to impaired airway patency. This may be due to defects in the anesthesia machine. Before starting anesthesia, it is necessary to check the functioning of the device, its tightness and the permeability of gases through the breathing hoses. Airway obstruction may occur as a result of retraction of the tongue during deep anesthesia (level III of the surgical stage of anesthesia). During anesthesia, solid foreign bodies (teeth, prostheses) can enter the upper respiratory tract. To prevent these complications, it is necessary to advance and support the lower jaw against the background of deep anesthesia. Before anesthesia, the dentures should be removed, the patient's teeth should be examined.

Complications of tracheal intubation performed by direct laryngoscopy can be grouped as follows:

1) damage to the teeth by the laryngoscope blade;

3) introduction of an endotracheal tube into the esophagus;

4) introduction of an endotracheal tube into the right bronchus;

5) exit of the endotracheal tube from the trachea or bending it.

The described complications can be prevented by a clear knowledge of the intubation technique and control of the position of the endotracheal tube in the trachea above its bifurcation (using auscultation of the lungs).

Complications from the circulatory system. A decrease in blood pressure both during the period of anesthesia and during anesthesia can occur due to the effect of narcotic substances on the activity of the heart or on the vascular-motor center. This happens with an overdose of narcotic substances (often halothane). Hypotension may appear in patients with low BCC with the optimal dosage of narcotic substances. To prevent this complication, it is necessary to fill the BCC deficit before anesthesia, and during the operation, accompanied by blood loss, transfuse blood-substituting solutions and blood.

Heart rhythm disturbances (ventricular tachycardia, extrasystole, ventricular fibrillation) can occur due to a number of reasons:

1) hypoxia and hypercapnia resulting from prolonged intubation or insufficient ventilation during anesthesia;

2) overdose of narcotic substances - barbiturates, halothane;

3) the use of epinephrine against the background of halothane, which increases the sensitivity of halothane to catecholamines.

Electrocardiographic control is needed to determine the heart rhythm. Treatment is carried out depending on the cause of the complication and includes the elimination of hypoxia, a decrease in the dose of the drug, the use of quinine drugs.

Cardiac arrest is the most dangerous complication during anesthesia. It is most often caused by incorrect control of the patient's condition, errors in the technique of anesthesia, hypoxia, hypercapnia. Treatment consists of immediate cardiopulmonary resuscitation.

Complications from the nervous system.

During general anesthesia, a moderate decrease in body temperature is allowed as a result of the influence of narcotic substances on the central mechanisms of thermoregulation and cooling of the patient in the operating room. The body of patients with hypothermia after anesthesia tries to restore body temperature due to increased metabolism. Against this background, at the end of anesthesia and after it, chills appear, which is observed after halothane anesthesia. To prevent hypothermia, it is necessary to monitor the temperature in the operating room (21–22 °C), cover the patient, if necessary, infusion therapy, transfuse solutions warmed to body temperature, and inhale warm, moistened narcotic drugs. Cerebral edema is a consequence of prolonged and deep hypoxia during anesthesia. Treatment should be immediate, it is necessary to follow the principles of dehydration, hyperventilation, local cooling of the brain.

Peripheral nerve damage.

This complication occurs a day or more after anesthesia. Most often, the nerves of the upper and lower extremities and the brachial plexus are damaged. This is the result of an incorrect position of the patient on the operating table (abduction of the arm more than 90° from the body, placing the arm behind the head, fixing the arm to the arc of the operating table, laying the legs on the holders without padding). The correct position of the patient on the table eliminates the tension of the nerve trunks. Treatment is carried out by a neuropathologist and a physiotherapist.