Stages of anesthesia and their characteristics

Features of local anesthesia

Local anesthesia is understood as temporary anesthesia of a small area of the body due to the effect of external drugs on it or injection of a medicinal solution. In the definition one can immediately see a large classification of types of local anesthesia: superficial and internal. The latter, in turn, is divided into several more subtypes depending on the area of influence (epidural, conduction, spinal, infiltration).

Local anesthesia has found use in almost all areas of medicine, but the most striking example is dentistry. Today, almost all manipulations are performed with anesthesia. And if previously the patient had to endure 10-20 minutes while the doctor drills the tooth, cleans the canals, and puts a filling, now all pain is reduced to a second tingling sensation from the insertion of a thin needle.

How is it carried out?

All types of local anesthesia have their own characteristics, but on average it is something like this: a person is injected with medicine into a specific area. After a few minutes, sensitivity in this area is lost, and doctors can begin manipulation. The patient remains conscious, but he does not feel anything, not even the touch of a cold instrument. The general condition is also stable, although some admit to experiencing mild nausea and dizziness. But doctors attribute this more likely to anxiety than pain relief.

By the way! Sometimes, before inserting a needle, the skin is first numbed with external anesthetics to reduce pain from puncturing soft tissue. The result is a combined local anesthesia. It is used, for example, during epidural anesthesia.

How does anesthesia wear off?

The amount of anesthetic administered and the choice of its type are calculated based on the complexity of the operation and the patient’s physique. But the medicine is always taken with a reserve so that the anesthesia does not suddenly wear off during medical procedures if they require more time. Accordingly, after the end of the operation, the patient has a few more minutes (sometimes even a little more than an hour) for the anesthetic to stop working.

Sensitivity returns gradually, but quite quickly. First, a person begins to feel the touch, and after a minute or two he feels pain at the site of the manipulation. If it was a dental procedure, then the area where the gum was punctured or the hole after the extracted tooth may ache.

When treating caries, as a rule, no pain is felt after the anesthesia wears off. If it was a more complex operation, for example, to remove an ingrown nail, then the operated finger may begin to hurt quite severely because there was a violation of the integrity of the tissue. But these pains can be relieved with analgesics.

Possible complications

Some people are allergic to certain types of medications. Local anesthesia involves the use of Lidocaine, Novocaine, Bupivacaine, etc. And a person may experience a reaction to them in the form of:

These reactions appear immediately after administration of the drug. And if the first two are quite tolerable, then the last three require termination of the operation and hospitalization of the patient. You can find out if it is available by first conducting an allergy test.

Some people note certain reactions after the local anesthesia wears off: dizziness or headache, weakness, sleepiness, and fever. But it is impossible to say for sure whether this is an allergy to the medicine or consequences after the operation.

COMBINED GENERAL ANESTHESIA

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COMBINED GENERAL ANESTHESIA

Combined anesthesia is anesthesia that is achieved by simultaneous or sequential use of a combination of various drugs: general anesthetics, tranquilizers, analgesics, muscle relaxants. This allows you to significantly reduce the concentration of anesthetics in the patient’s body and their toxic effect on him. In such cases, anesthesia becomes more manageable; it becomes possible to reduce the concentration of a potent anesthetic to maintain anesthesia at a certain level. The most commonly used combinations of anesthetics are for intravenous and inhalational use.

Total intravenous anesthesia. With this type of anesthesia, a combination of several anesthetics is usually used for intravenous use. They are usually administered by continuous infusion. The most commonly used short-acting anesthetic is propofol in combination with fentanyl or another analgesic.

In the first 10 minutes, propofol is administered at a dose of 10 mg/kg, in the next 10 minutes - 8 mg/kg, in the next 8 minutes - 6 mg/kg. It is most convenient to perform the infusion with an automatic syringe using a target setting. The infusion rate is continuously calculated by a microprocessor built into the unit. The required dose of the drug is displayed on the display of the automatic syringe.

Balanced anesthesia. For balanced anesthesia, a combination of narcotic analgesics (morphine, fentanyl, sufentanil) with isoflurane (0.5%) or propofol (50-200 mg/kg per minute) is used.

Ataralgesia is a multicomponent balanced anesthesia based on the use of drugs from the benzodiazepine group in combination with narcotic analgesics. Through the use of sedative, tranquilizing and analgesic drugs, a state of ataraxia (literally this term means “equanimity, composure, calmness”) and pronounced analgesia is achieved.

REGIONAL ANESTHESIA

The most widespread in clinical practice are local infiltration superficial (terminal) and various types of conduction and regional anesthesia. Hypothermal, intraosseous, intravascular tourniquet and acupuncture anesthesia are rarely used. Currently, local anesthesia is the main type of anesthesia in outpatient and outpatient practice, as well as for minor surgical interventions.

Mechanism of action of drugs for local anesthesia

Drugs in this group block the transmission of nerve impulses at the site of interaction of their molecules with nerve fibers. In this case, anesthesia occurs in the entire area innervated by the blocked nerve and its endings. First of all, thin unmyelinated type C fibers, which provide pain sensitivity, are excluded from the process of nerve impulse transmission during local anesthesia. Tactile sensations are preserved; they disappear later after blockade of myelinated type A fibers. Last of all, with local anesthesia, motor fibers are blocked. The mechanism of action of drugs for local anesthesia is due to the fact that they prevent the occurrence of a nerve impulse and reciprocally block its transmission through the nerve fiber. The main target of action of drugs for local anesthesia is the membrane of the nerve cell, which plays a major role in the generation and transmission of nerve impulses. Local anesthetic drugs disrupt the permeability of membranes to Na+ ions when an action potential occurs, making it impossible to depolarize the nerve cell and thus block the perception and conduction of nerve impulses. They cause a non-depolarizing blockade by stabilizing polarized membranes.

Local anesthetic drugs of the ester group (in particular novocaine) are hydrolyzed by blood plasma esterases and are quickly destroyed. Amide derivatives (lidocaine, grimecaine, pyromecaine, etc.) act longer, since they do not hydrolyze in the blood plasma, but disintegrate in the liver. Today, procaine (novocaine), lidocaine, bupivacaine and ropivacaine are mainly used in anesthesiological practice.

Preparing for local anesthesia

Before performing local anesthesia, the anesthesiologist must participate in the preoperative examination and preparation of the patient for surgery. To reduce mental trauma, ensure good sleep and prevent the toxic effects of local anesthetics, patients are prescribed special premedication before anesthesia. It is especially indicated for persons with an increased level of metabolic processes and excitability of the nervous system (thyrotoxicosis, neuroses). Before starting pain relief, it is necessary to prepare equipment, supplies and appropriate therapeutic agents for artificial ventilation, oxygen inhalation, removing the patient from cardiovascular collapse and eliminating allergic reactions.

Epidural anesthesia

In this type of anesthesia, a local anesthetic is injected into the epidural space, which does not communicate with the spinal cord or brain, so it does not directly affect the brain. This is the main advantage of epidural anesthesia over spinal anesthesia.

An anesthetic solution injected into the epidural space bathes the spinal nerve roots emerging from the spinal cord into the epidural space. In addition, through the intervertebral foramina it enters the boundary pillars, blocking them. This causes a blockade of sympathetic, sensory and motor innervation. As a rule, anesthesia covers a significant area, since the anesthetic solution in the epidural space rises up and falls down by 5-8 segments (with the introduction of 10-16 ml of anesthetic).

Patients scheduled for surgery under epidural anesthesia should be carefully assessed and appropriately prepared for surgery. It is especially important to replenish their circulating blood volume, since in case of hypovolemia it is dangerous to use this type of anesthesia. Premedication should not be excessive. Neuroleptics cannot be used with it. Before anesthesia, an intravenous infusion of 400-500 ml of crystalloid or colloid blood replacement solutions is performed.

Epidural anesthesia is performed with the patient sitting or lying on his side with his legs adducted to his stomach. The choice of puncture site is determined by the desired level of anesthesia. The puncture is performed at a level corresponding to the center of the selected anesthesia zone.

For anesthesia, two needles are used: one for hypodermic injections, the other for performing a blockade. Using the first needle, preliminary anesthesia of the skin and its main layer is carried out. Then the insertion site of the second needle is determined between the spinous processes. For the blockade, a special Tuohy needle is used, having a length of up to 10 cm and an internal diameter of about 1 mm, with a sharp but short and curved end. It is inserted into the spine between the spinous processes strictly along the posterior midline to a depth of 2-2.5 cm, in the lumbar region - perpendicular to the spine, in the thoracic region - at a slight downward angle, corresponding to the direction of the spinous processes (Fig. 34, a). Then a syringe filled with an isotonic sodium chloride solution and an air bubble in it is attached to the needle. Further advancement of the needle deeper is carried out by observing the degree of compression of the air bubble in the syringe.

Before entering the epidural space, the needle passes through the skin, subcutaneous layer, supraspinous, interspinous and yellow ligaments. While the end of the needle is between the fibers of the ligaments, the solution flows out very slowly when you press the syringe plunger, and the air bubble in it contracts. As soon as the needle penetrates the epidural space, the resistance to the solution decreases and the piston moves forward easily. The air bubble does not compress. When disconnecting the syringe from the needle, no liquid should flow out of it. If fluid flows out, this indicates that the tip of the needle has entered the vertebral (spinal) canal. When the needle is guaranteed to have penetrated the epidural space, 2-3 ml of anesthetic solution is injected into it to push back the spinal dura and prevent its perforation by the needle or catheter. Then a thin polyethylene catheter is inserted into the needle (Fig. 34, 6), through which the anesthetic is administered fractionally or infusionally during and after the operation, thereby providing long-term anesthesia. First, a test dose of anesthetic is administered, usually 2-3 ml of a 2% lidocaine solution or 0.5% bupivacaine. After making sure that there are no signs of allergic or other undesirable reactions, the catheter is fixed and after 5-8 minutes the entire dose of the drug is administered. For a complete blockade of one segment of the spinal cord, adult patients require 1-2.5 ml of a solution of the drug for local anesthesia. Since in elderly and senile patients the volume of the epidural space is reduced as a result of sclerosis of the fiber filling the space, the dose of the drug for local anesthesia is reduced by 30-50%.

Fig. 34. Technique of puncture (a) and catheterization (b) of the epidural space.

To maintain long-term postoperative analgesia, the catheter is left in the epidural space after surgery (so-called extended epidural anesthesia).

Possible complications with epidural anesthesia: 1) collapse (the higher the level of epidural anesthesia, the greater the risk of its development). Collapse can be easily prevented by administering a 0.5% ephedrine solution in a low dose (in fractions of 1-2 ml) in parallel with active infusion therapy; 2) breathing problems with a high level of epidural anesthesia; in these cases, artificial ventilation is required; 3) headache, pain at the puncture site; 4) traumatic radiculitis; 5) infection of the epidural space.

Indications for the use of epidural anesthesia: 1) large-scale surgical interventions in the lower abdominal cavity, urological, proctological operations and operations on the lower extremities; 2) operations in elderly and senile people, with concomitant cardiopulmonary pathology, metabolic disorders, liver and kidney function, in the practice of childbirth; 3) in the presence of postoperative pain syndrome.

Epidural anesthesia is also used for the purpose of quickly restoring intestinal motility after operations on the abdominal organs, in the complex treatment of a number of diseases (acute pancreatitis, peritonitis, intestinal obstruction, with some pain syndromes and circulatory disorders in the extremities).

Contraindications: 1) the presence of inflammatory processes in the area of the intended puncture or generalized infection; 2) hypovolemia, hypotension, severe shock; 3) increased sensitivity to drugs for local anesthesia; 4) diseases of the spine that make it difficult to insert a needle into the epidural space; 5) diseases of the peripheral and central nervous system.

Advantages of epidural anesthesia: 1) the ability to achieve segmental anesthesia, accompanied by sufficient muscle relaxation and blockade of sympathetic innervation; 2) the possibility of lowering blood pressure (if necessary); 3) providing long-term analgesia in the postoperative period and early restoration of motor activity of patients.

REGIONAL ANESTHESIA

Spinal anesthesia

In this type of anesthesia, a solution of a local anesthetic drug (bupivacaine, lidocaine) is injected into the subarachnoid space after puncturing the dura mater. In this case, the anesthetic quickly interacts with the nerve roots and provides pain relief to the entire part of the body located below the puncture site. If the relative density of the injected anesthetic solution is less than the relative density of the cerebrospinal fluid, then it moves to the higher parts of the spinal cord. As a rule, a 2% lidocaine solution (3-4 ml) or 0.5-0.75% bupivacaine (2-3 ml) is used for spinal anesthesia. The duration of anesthesia when using lidocaine is 1 hour, and bupivacaine is 1.5-2 hours.

Spinal anesthesia is often used for operations on organs located below the diaphragm and in operations on the lower extremities. The introduction of an anesthetic above the level of the ThXII vertebra can cause disruption of the vasomotor and respiratory centers. Even with low levels of anesthesia, there is usually a decrease in blood pressure. Arterial hypotension occurs as a result of the influence of the anesthetic on the connecting branches that conduct vasoconstrictor impulses from the vasomotor center to the periphery. This causes paralysis of the vasomotor nerves (visceral and somatic).

The technique of spinal anesthesia is simpler than epidural, since the flow of fluid from the needle is an accurate indicator of entry into the spinal canal. Most often, the puncture is performed between the vertebrae L1-L2, or L2-L3. .

The patient's position on the operating table depends on the type of anesthetic used. When performing anesthesia with a drug whose relative density is less than the relative density of the cerebrospinal fluid, the patient after performing a spinal puncture in a sitting position and administering the drug should be placed on his back so that the solution does not have time to move upward. If the puncture is performed in a lying position, the level of anesthesia is regulated by changing the position of the operating table.

Advantages of spinal anesthesia: high efficiency and achievement of relaxation of the abdominal muscles.

Disadvantages of spinal anesthesia: the development of severe arterial hypotension, respiratory depression, headache, urinary retention, and manifestations of meningism are possible. If a needle accidentally damages the roots of the spinal nerves, the patient may experience traumatic radiculitis. The use of thin, pointed spinal needles (25-27 gauge) significantly reduces the incidence of postoperative headache.

For an experienced anesthesiologist, even such a complication as respiratory arrest is not threatening. If breathing stops, it is necessary to intubate the trachea and begin artificial ventilation. In the event of severe arterial hypotension, it is necessary to start an infusion of blood plasma substitutes; if there is no effect, administer adrenergic agonists (ephedrine, phenylephrine/mesatone).

Extended spinal anesthesia is used for surgical interventions of any duration performed in the ThIV-SV innervation zone. To do this, catheterization of the subarachnoid space is performed. A 0.5% bupivacaine solution is used as an anesthetic. The initial dose of the drug is 3-4 ml (15-20 mg), repeated - 1.5-3 ml (7.5-15 mg). A repeat dose is administered after 3-3.5 hours. For postoperative pain relief, a 0.125% solution of bupivacaine is used in a dose of 3-4 ml (3.75-4 mg) or fentanyl - 50 mg.

Complications of local anesthesia

Complications arising from local anesthesia are conventionally divided into complications caused by improper execution of anesthesia technique, overdose of anesthetic and hypersensitivity to it. Complications caused by the peculiarities of the technique of performing various types of local anesthesia have been covered previously.

The clinical picture of poisoning with local anesthetics (yawning, restlessness, disorientation in space, tremor, headache, nausea, vomiting, generalized tonic and clonic convulsions) is due to their effect on the central nervous system. In severe cases of poisoning, death occurs from paralysis of the respiratory tract. The effect of the anesthetic on the cardiovascular system first manifests itself in tachycardia and arterial hypertension. Subsequently, a decrease in electrical excitability, conductivity and contractile function of the myocardium occurs with the occurrence of bradycardia and arterial hypotension, up to cardiac arrest. If a toxic reaction to an anesthetic occurs, it is necessary to inject the patient intravenously with fat emulsions, such as lipofundin, and artificially support basic vital functions (artificial ventilation, oxygen therapy, inotropic support, infusion therapy).

Frequent complications of local and regional anesthesia are anaphylactic reactions in patients with hypersensitivity to drugs for local anesthesia: allergic skin reaction, cardiovascular collapse (pale skin, cold extremities, cold clammy sweat, sharp decrease in blood pressure, unconsciousness) or anaphylactic shock.

Prevention and treatment of these complications should be etiopathogenetic.

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Features of general anesthesia

A more complex type of anesthesia, which involves immersing the patient in a narcotic sleep and completely depriving him of not only sensitivity, but also consciousness. It is difficult for people who have never been exposed to this in their lives to imagine such a state. Therefore, many people are afraid of their first operation under general anesthesia.

General anesthesia is also successfully used today in all areas of medicine. Moreover, sometimes this is the only chance to perform the operation. In dentistry, this type of pain relief is also used when a person (usually a child) is unable to overcome his fear of going to the dentist.

There are two main types of general anesthesia: inhalation (through a mask) and. Sometimes combined anesthesia is used. What it will be in a particular case is decided by the doctor, depending on the specifics of the operation and the physiology of the patient.

What is it made up of?

General anesthesia consists of three “components”: analgesia and muscle relaxation. In essence, a person simply falls asleep, but in fact completely different changes occur in his body. During normal sleep, breathing is calm, the body is relaxed, but reflexes are preserved.

And if you prick a person with a pin or simply pat him, he will wake up. And narcotic sleep also implies analgesia - suppression of the body’s autonomic reactions to all types of interventions: punctures, incisions, manipulation of internal organs, etc.

The third “component” of general anesthesia – muscle relaxation – is necessary to facilitate the work of surgeons during surgery. Due to the presence of muscle relaxants in the medicinal solution, the patient’s muscles are as relaxed as possible and also cannot reflexively react to interventions (contract, tense).

How is it carried out?

If this is general anesthesia of the inhalation type, then a mask is put on the patient’s nose and mouth, through which a gas-narcotic mixture is supplied. A person is required to breathe evenly and not resist the onset of sleep. Using sensors connected to the body, the anesthesiologist determines when the anesthesia has fully taken effect and signals this to the surgeons.

Involves the administration of drugs through the skin. This anesthesia is considered deeper and more reliable, while inhalation anesthesia is used for simple operations. If a difficult and lengthy intervention is ahead, then combined anesthesia is used: first, then a mask is added.

By the way! During general anesthesia, doctors must monitor the main indicators of the body’s vitality, thanks to equipment and external signs. The patient’s skin color, body temperature, heart function, pulse - all this allows you to monitor the course of anesthesia and the person’s condition.

How long does it take to recover from general anesthesia?

People sometimes fear for their well-being when they come out of general anesthesia after surgery because it is a complex process. Although, it is difficult for the anesthesiologist, but rather unpleasant for the patient. It's like waking up from a very heavy sleep. In this case, the following sensations may be noted:

If the general anesthesia was light, then the patient after the operation goes to the ward and “wakes up” on his own. After deep anesthesia, a person must be “awakened” by an anesthesiologist. This can happen directly in the operating room, or in the intensive care unit after some time.

By the way! Some people recover from general anesthesia for hours, experiencing the full range of symptoms listed above.

Possible consequences

General anesthesia is stress for the body, which during its action actually balances on the brink of life and death. Yes, everything happens under the control of a medical team, but still breathing almost stops, there are no reflexes, the heart beats very weakly. Therefore, consequences associated with disruption of the normal functioning of the cardiovascular and respiratory systems are not uncommon. This is manifested by a decrease or increase in pressure, spasms of the larynx and bronchi, sputum production, and hiccups.

Is it possible to make recovery from anesthesia easier?

You can reduce the intensity of discomfort if you properly prepare for surgery. To do this, you need to openly tell your doctor about the illnesses you have suffered and your concerns, follow a diet, and conscientiously take the prescribed medications. If the patient is self-willed in preoperative preparation, eats in secret from doctors, runs around smoking or takes some pills, then this will create problems during surgery. Moreover, they will be associated not only with immersion in and recovery from anesthesia, but also with the course of the operation itself. It is necessary to follow medical recommendations even after general anesthesia has stopped working. If your doctor allows you to get up and walk, you need to do this to prevent thromboembolism (blockage of the venous vessels). Some people are advised to simply move their legs for the same reason. It is not recommended to grab a book or smartphone immediately after waking up: it is better to rest and think about something good, for example, that everything is behind. And under no circumstances should you ignore the doctor’s instructions, which may vary depending on the type of anesthesia and the operation performed.

Every person who is about to undergo surgery under general anesthesia experiences natural anxiety and curiosity. These worries are understandable, since even today’s advanced advances in medicine do not make it possible to predict 100% the consequences of both the operation itself and general anesthesia. People have individual tolerance to anesthesia, which affects everyone differently, so it is impossible to predict exactly what sensations the patient will experience after anesthesia.

How general anesthesia can affect the body, and what the recovery from it will be, depends on a number of factors:

age;
hormonal status;
presence of chronic diseases;
proper preparation for surgery;
presence of bad habits;
allergic reactions.

Each person handles general anesthesia differently.

A large degree of responsibility falls on the shoulders of the anesthesiologist, who must carefully study the patient’s medical record and make the right choice regarding anesthetic drugs and the method of their administration. The anesthesiologist is obliged to conduct a conversation with the patient about the proper preparation of the body for the upcoming surgical intervention. The doctor should give the most complete answer to the patient’s questions about how long and exactly how he will recover from general anesthesia, without hiding the likelihood of complications.

It is important to remember that going into medicated sleep under general anesthesia is a justifiable risk. However, it has been experimentally proven that if the patient properly prepares his own body for surgery, anesthesia works reliably and recovery from it is not accompanied by severe symptoms.

When to use anesthesia

Often children, especially teenagers, behave quite calmly. While carrying out the necessary work, explanations, clarifications, the baby remains balanced throughout these half an hour. These are, of course, rare cases, but they do happen.

Children are given anesthesia for an MRI if they are afraid or cannot lie still

Anesthesia is indicated if the patient feels discomfort, constantly moves during the procedure, or is afraid. Medication-induced sleep is very harmless. As for children, it is better to use intravenous anesthesia. Hypnotic sleep is easily tolerated. As the drug is administered, the patient sleeps, but as soon as the doctors stop giving the infusion, the patient comes out of the sleep state.

It is preferable to perform the procedure on young patients under anesthesia rather than performing an MRI on children without anesthesia. Firstly, this way you can get accurate results. Secondly, there will be no consequences for the child.

Read also: features of MRI for children.

Pros and cons of general anesthesia

Despite the fact that recovery from anesthesia is often unpleasant, this procedure is necessary. Anesthesia is widely used in many areas of medicine. During the operation, a person in a state of artificial sleep does not experience pain and lies motionless on the operating table, providing surgeons with ideal working conditions. The absence of many reflexes, relaxed muscles and peace of mind of the patient give specialists the opportunity to perform even the most complex manipulations effectively and efficiently.

General anesthesia has a number of advantages, which makes it indispensable during surgery. A person who is in a deeply inhibited state receives protection from painful shock, which would otherwise cause irreparable damage to his physical and mental health. The absence of a sense of panic and fear is beneficial for the patient himself and for those who treat him.

General anesthesia helps doctors to perform the operation calmly

Before the upcoming operation, you need to talk with the anesthesiologist, who should be told about all your fears.

In the recent past, highly toxic drugs have been used to promote medicated sleep. However, today in developed countries only anesthetics that are gentle on the body are used. The patient’s main task is not to hide information from the anesthesiologist that may be important when choosing an anesthetic drug. False shame about illnesses suffered in the recent past or about taking illegal drugs leads to sad consequences.

The disadvantages of coming out of artificial sleep include the fact that after anesthesia the following unpleasant sensations are possible:

visual hallucinations;
auditory hallucinations;
nausea;
vomit;
stomach pain;
headache;
severe dry mouth;
sore throat;
feeling very tired.

In each case, there are ways to reduce the risk of developing unpleasant symptoms after anesthesia. To do this, it is important to honestly follow the recommendations of the anesthesiologist before surgery. All the doctor's questions must be answered truthfully. If these conditions are met and the drug combination is correctly selected, patients recover from anesthesia quickly and without complications.

How do you come out of anesthesia?

After surgery, people recover from general anesthesia individually and unpredictably. How long this period lasts depends on the specific circumstances each time. Some patients emerge from artificial sleep a few minutes after the end of the operation. After half an hour they regain consciousness, and an hour later they take their first sip of water. Other patients recover from general anesthesia for hours, while experiencing not the most pleasant experiences in life.

A person’s condition after anesthesia depends on a number of factors.

How long it will take to recover from anesthesia after surgery depends on its type and duration. For simple surgical interventions, if the patient’s body condition allows, the anesthesiologist “wakes up” him after the operation right in the operating room. In this case, after 5 or 6 hours the patient comes to his senses. He is able to eat liquid broth, communicate with other people and even move independently.

Coming out of anesthesia is often accompanied by a feeling of severe pain in the area injured during surgery. Patients should report any pain symptoms that occur during recovery from this state. There is no need to endure and suffer. A warning about the sensations experienced will allow doctors to promptly relieve excessive pain and help make recovery from anesthesia less difficult for the body.

Stages of anesthesia

Path: Medical blog of Andrey Novitsky > Stages of anesthesia

When general anesthetics are introduced into the body, a natural phasing pattern has been established in the clinical picture of general anesthesia, which is most clearly observed when using ether. Manifestations of anesthesia with other anesthetics develop similarly, but the division of manifestations into stages is less pronounced. Knowledge of the clinical picture of each stage helps the anesthesiologist when performing general anesthesia. The most widely used classification of stages of anesthesia is Gwedel A., modified by I.S. Zhorov. Classification of stages of anesthesia (according to A. Guedel): I. The stage of analgesia begins from the moment of inhalation of ether vapor. After a few minutes, loss of consciousness occurs: speech becomes incoherent, drowsiness appears. The facial skin is hyperemic. The pupils are the original size or dilated and react to light. Breathing is rapid and irregular. Heart rate is increased, blood pressure is slightly increased. Tactile and temperature sensitivity are preserved, pain sensitivity is weakened, which allows short-term manipulations. II. The stage of excitation begins immediately after loss of consciousness and is characterized by speech and motor arousal. The skin is hyperemic. The eyelids are closed, the pupils are dilated, the photoreaction is preserved, the ciliary reflex is absent; lacrimation and swimming movements of the eyeballs appear. Breathing is frequent and arrhythmic. Heart rate and blood pressure are increased. Cough and gag reflexes are strengthened. Muscles are tense, trismus. When stimulating the larynx and pharynx, laryngospasm is possible. During this stage, ventricular fibrillation of the heart may develop, and rarely, involuntary urination and vomiting. III. Surgical stage III 1. Against the background of restful sleep, muscle tone and laryngeal-pharyngeal reflexes are still preserved. The pupils are constricted and react to light; corneal reflex preserved; slow movements of the eyeballs. Breathing is even, somewhat rapid. Heart rate is increased, blood pressure is at the initial level. III 2. The skin is pink, the mucous membranes are moist. The pupils are constricted, the photoreaction is preserved; there is no corneal reflex; eyeballs are fixed. Breathing is even. Heart rate and blood pressure at baseline. Laryngeal and pharyngeal reflexes are absent. Muscle tone is reduced. III 3. Appearance of signs of toxic action of the anesthetic. The skin is pale pink. The pupils are dilated, the photoreaction is weakened; dry cornea. Breathing is diaphragmatic, rapid. Heart rate increased, blood pressure decreased. Muscle tone is reduced. III 4. Appearance of signs of anesthetic overdose. The skin is pale cyanotic. The pupils are sharply dilated, there is no photoreaction. Only diaphragmatic breathing is preserved - shallow, arrhythmic. Heart rate is sharply increased, the pulse is frequent, thread-like; Blood pressure dropped sharply. If the anesthetic continues to flow, further depression of respiration and circulation occurs and a terminal condition develops. This level is unacceptable in clinical practice. IV. The awakening stage occurs after the cessation of the anesthetic and is characterized by the gradual restoration of reflexes, muscle tone, sensitivity and consciousness in the reverse order.

This page was published on 01/30/2011. Tags: anesthesiology

What to do during a long recovery from anesthesia?

Surgical operations are planned. The person who is prescribed such an intervention receives enough time from the doctor for the most thorough preparation. The quality of this preparation largely determines how long and exactly how the patient will recover from anesthesia.

Most people who have been operated on under general anesthesia for a long time (from 3 hours) come to their senses within 1–3 days from the moment the effect of the anesthetic drugs wears off. Since the same anesthetics have different effects even on patients with similar histories, the likelihood of accurately determining the time is low, but rough estimates can be made.

While the patient is emerging from unconsciousness, he periodically regains consciousness. At these moments, the health worker asks the patient questions about his well-being, which are important to answer without hesitation. There is no need to endure pain, severe nausea or gag reflexes, since medicine has sufficient ways to correct these problems.

Before and after surgery, a person experiences an uncontrollable feeling of fear. However, you should not fight panic on your own. If there are obsessive experiences, a consultation with a psychologist is necessary even before the operation begins. If the patient’s relatives take part in his fate, they also need a conversation with a psychologist. The support of relatives, with proper support, will help the patient prepare for the upcoming surgical treatment and allow him to more easily endure the consequences of anesthesia.

When organizing care for surgical patients, it is necessary to keep in mind that any surgical intervention is accompanied by the development of stress in them, and most operations are performed under general anesthesia. Both circumstances require close attention to the patient in the coming hours after surgery.

With complete restoration of consciousness, stabilization of breathing and hemodynamics, the patient can be transferred to a specialized department. In the same case, when there is the slightest doubt or the likelihood of a complication, the patient is transferred to the postoperative (post-anesthesia) ward, which should be directly adjacent to the operating unit. If there is no such ward, then the patient is transported to the intensive care unit.

The patient is transported on a gurney, accompanied by an anesthesiologist who performed anesthesia. During transportation, cardiac and respiratory arrest may occur, during which resuscitation measures are immediately carried out.

In the ward, the patient is placed on his side, thereby preventing vomit, saliva or mucus from entering the respiratory tract in case of vomiting. After restoration of protective reflexes and consciousness, the patient is given the desired position. The patient, who is in a state of excitement, is secured with soft straps. Then the monitoring equipment is connected. Monitoring of patients is organized by an anesthesiologist-resuscitator and conducted by a nurse anesthetist

The main
patient
management in the immediate future after surgery are:

 prevention of respiratory failure;

 prevention of circulatory and homeostasis disorders;

 relief of pain syndrome;

 prevention of infectious complications.

Respiratory depression may occur in the postoperative period

due to the ongoing effect of substances that were used during anesthesia (anaesthetics, narcotic analgesics, muscle relaxants). Weak diaphragmatic breathing and paradoxical movements of the chest (during inhalation it is the chest) are indications for artificial ventilation.

Restoration of synchronous respiratory movements of the chest and abdomen (diaphragmatic breathing), as well as sufficient muscle strength, when the patient can shake hands, raise his head and hold it in this position for at least 2 seconds, indicates the cessation of the influence of medicinal substances.

During the period when the patient recovers from anesthesia, oxygen starvation (hypoxia) may be observed, the most important symptom of which is cyanosis (bluish tint) of the skin, but its absence does not exclude hypoxia. The main cause of hypoxia is a violation of the free patency of the respiratory tract. Vomiting and regurgitation of gastric contents are especially dangerous. Vomit

occurs due to the action of anesthetics and narcotic analgesics, as well as as a result of hypoxia during anesthesia and in cases where the stomach is full.
When the patient lies horizontally or with the head down, regurgitation
(fluid flow in the direction opposite to the physiological) of gastric contents may occur, i.e. its passive flow into the oral cavity.

If vomit enters the respiratory tract, i.e. during their aspiration

, occlusion of the bronchial tree may occur.
Patients experience mechanical asphyxia, which ends in respiratory arrest and death. This complication is prevented by emptying the stomach
with a tube before surgery, and after the operation is completed, the contents are removed from the stomach again.
By placing the patient in a lateral position after surgery,
aspiration of gastric contents is prevented, as well as
tongue retraction
, which can also lead to asphyxia. This situation does not completely exclude the occurrence of these complications and is standard when transporting unconscious patients. As an exception, it is applicable when, when removing the patient from anesthesia, protective reflexes are not sufficiently restored. To prevent the tongue from recessing, they use an air duct or resort to the so-called triple Safar maneuver (throwing the head back, pushing the lower jaw forward and opening the mouth slightly).

If this complication occurs, the head end of the patient's body is lowered down. Then the mouth is cleaned with a napkin or suction. The trachea is freed from vomit by pressing from the sides on the chest. The patient is intubated and the bronchial tree is washed in small portions with a solution of baking soda and the liquid is suctioned, or a sanitation bronchoscopy is performed.

Increased pain in the surgical area limits the depth of breathing and prevents coughing up mucus. Insufficient ventilation of the lungs, including when bronchioles are blocked by mucus, leads to the formation of atelectasis

when part of the lung loses its airiness, collapses and inflammation develops here.
To prevent this, rational pain relief
.
Breathing exercises
are important , every hour the patient must take 5 deep breaths and exhalations, also
change body position
,
early active movements
up to standing up and chest massage.
When sputum is discharged once every 3-4 hours for a few minutes, the patient is given a postural position
(on one side or another, on the back), in which the mucus moves well into the large bronchi and is coughed up relatively easily. If there is a large amount of sputum, direct laryngoscopy is performed, a thin catheter is inserted through the glottis and the mucus is actively aspirated.

Circulatory disorders

in the postoperative period is often associated with hypovolemia (decreased fluid in the body), which exists before or occurs during and after surgery. In order to prevent these disorders, the missing fluid is replenished by transfusion of electrolyte solutions and plasma substitutes. To determine the required volume of infusions, an accurate record of the fluid excreted in urine, feces, vomit, through drains, fistulas, gastric and intestinal tubes is kept.

To carry out infusion therapy, venipuncture or venesection is performed. The most optimal method is catheterization of the main vein. The catheter can be a conductor of infection, and when caring for it, promptly change the contaminated material that is used to fix it to the skin. In case of phlebitis, infusion into this vein is stopped and the catheter is removed. The venous catheter becomes thrombosed, and blood clots form around it. Thrombus rupture leads to thromboembolic complications,

to avoid which, the catheter is regularly, 2-3 times a day, washed with saline solution with heparin.

When dehydration occurs, negative central venous pressure is observed; its suction effect contributes to the entry of air through the dropper into the vascular bed and the occurrence of air embolism

. To prevent it, during infusions, monitor the absence of air bubbles in the system and its tightness at the junction with the catheter. After the end of the infusion, the catheter cannula is closed with a special plug.

Upon learning about the upcoming operation, and therefore anesthesia, any patient experiences excitement. Every person understands perfectly well that anesthesia is performed specifically for pain relief, but the stories of friends and acquaintances about how hard the human body endures this procedure frighten patients a lot. We'll tell you how long it takes to recover from anesthesia and what causes this condition.

Carrying out an MRI under general anesthesia

The peculiarity of MRI is that during the procedure the patient must lie absolutely still (from 20 to 90 minutes). While in the tomograph coil, the patient may experience a feeling of enclosed space. The examination is accompanied by loud noise. Therefore, in some categories of patients, MRI must be performed under anesthesia.

In what cases MRI

Is it performed under anesthesia?

Feature of MRI

is that during the procedure the patient must lie absolutely still (from 20 to 90 minutes). While in the tomograph coil, the patient may experience a feeling of enclosed space. The examination is accompanied by loud noise.

Therefore, in some categories of patients, MRI must be performed under anesthesia.

Indications for anesthesia arise:

in patients suffering from claustrophobia or panic attacks;
in young children, starting from infancy;
in patients with hyperkinesis and forced body position due to pain (for example, with severe radiculitis);
in patients with inappropriate behavior due to mental disorders.

Carrying out MRI under anesthesia serves as a solution to the above problems.

What types of anesthesia are used for MRI?

Depending on the specifics of a particular case, this may be:

deep sedation (drug relief of anxiety and fear, bringing into a state of calm), achieved using modern tranquilizers, or

superficial anesthesia, which can be either intravenous or inhalational. In some particularly difficult cases, anesthesia must be supplemented with artificial ventilation.

At the Scandinavia

any of the above types of anesthesia are used in a qualified manner.
The choice of the optimal method of anesthesia is made by the anesthesiologist
, taking into account the characteristics of each case.

What are the characteristics of anesthesia for MRI?

The main feature is that the study is carried out under conditions of a strong magnetic field, which disrupts the operation of conventional anesthesia machines and monitors. Therefore, in MRI rooms

special, very expensive anesthesia-respiratory and monitoring equipment is used, capable of operating in a magnetic field.

In addition, the patient is monitored during the study from a neighboring office through a window, so special monitors must be connected to it to continuously monitor the state of his vital functions. Special means are required to reliably ensure airway patency.

At the Scandinavia

There are all the above-mentioned devices and materials certified for qualified provision of anesthesia in an
MRI room
. We can provide anesthesia services of any complexity in accordance with modern patient safety standards. In addition, we provide anesthesiological and resuscitation support for MRI studies in patients undergoing artificial ventilation.

How is anesthesia performed during MRI?

During sedation, the drug is administered intravenously using a special dispenser, and oxygen is inhaled through a light face mask.

For anesthesia in our clinic, in most cases, Sevoran (Sevoflurane) is used, an inhalational anesthetic of the latest generation. Compared to intravenous anesthesia, inhalation anesthesia with Sevoran has a number of advantages. Sevoran is non-toxic, hypoallergenic, and the rate of saturation of the patient with it, as well as the rate of its removal from the body when the supply is stopped, makes anesthesia very manageable. Consciousness turns off after a few breaths, which is especially important in young children, since it allows one to avoid traumatizing the child’s psyche with various painful manipulations, such as intramuscular and intravenous injections.

In adults, induction of anesthesia is performed with an intravenous anesthetic, after which anesthesia is maintained with sevoran. Intravenous anesthesia is also possible. After stopping Sevoran inhalation, signs of consciousness appear within a few minutes. Within half an hour, the patient awakens completely and can be released from the clinic.

During anesthesia, we use a special air duct - the so-called. laryngeal mask, which makes it possible to avoid tracheal intubation and associated risks. Connecting the laryngeal mask to the breathing circuit of the anesthesia machine allows you to reliably supply the patient with a respiratory mixture, and, if necessary, perform mechanical ventilation.

Recommendations for a patient who is scheduled to undergo MRI under sedation or anesthesia

Before anesthesia:

Undergo an examination prescribed by your attending physician (tests, examination by a therapist, specialists, if necessary).
Before anesthesia, for adults and children over 6 years old - the last meal no later than 9 hours before, for children under 6 years old - 6 hours before. The last intake of clean liquid (ONLY water, tea, clarified juice is acceptable) no more than 200 ml (for children - no more than 100 ml), and no later than 2 hours before the scheduled time of the study.
In case of planned treatment with any drugs, discuss with the anesthesiologist the need to take them on the day of the study (consultation by telephone is possible).
Do not apply makeup to your face before the examination.
Remove all jewelry (watches, rings, chains, earrings).
Remove removable dentures, if any.
If you wear contact lenses, notify the anesthesiologist about this. Carry a kit for contact lenses (container, rinsing liquid).

After anesthesia:

Take liquid no earlier than 30 minutes later.
Eating no earlier than 2 hours later, unless otherwise instructed by the anesthesiologist.
It is prohibited to drive vehicles, use power tools, or perform other potentially dangerous work that requires increased concentration for 24 hours after anesthesia.
After anesthesia, you can leave the clinic, preferably with an accompanying person, no earlier than 30 minutes (usually 1 hour) after the examination by the anesthesiologist.

Preparing for anesthesia

Anesthesia is an anesthesia of the body, which is accompanied by artificial sleep. Under the influence of the administered drugs, the human body loses pain sensitivity. High-quality anesthesia and rapid recovery from anesthesia largely depend on the anesthesiologist, whose task is to select the appropriate combination of narcotic drugs, depending on the individual characteristics of the patient, and therefore with minimal risk of adverse consequences.

Why is sedation and anesthesia used during MRI?

Anesthesia is given when the patient is an infant, and MRI is indicated in this case if it does not make sense to conduct an x-ray or ultrasound. Sedation is the most modern method of anesthesia. Doctors consider it the safest. When the drug is administered, the patient's consciousness remains with it. The baby is calm, does not move, lies flat. Depending on temperament and indications, a small patient may undergo superficial or deep sedation.

For deep cases, the most modern tranquilizers are used. This is guaranteed to relieve fear in an adult and makes it possible to carry out the procedure without incident. But tranquilizers are contraindicated for children.

Superficial sedation is an intravenous injection, often done as an inhalation. The person being examined is conscious and does not experience pain or anxiety.

If sedation is not enough, more serious anesthesia must be done. There are also contraindications to the use of tranquilizers in some patients. Therefore, doctors resort to general anesthesia. These are masks with drugs, intravenous infusions, etc.

For children, anesthesia is most often given in the form of inhalations.

The choice of the type of drug rests entirely with the anesthesiologist. Only he is able to determine what exactly a particular patient needs for examination using MRI.

The patient must be immobilized during the procedure. If this is a small child, it will be difficult to do this for a full 20 minutes or even half an hour. Adults may experience claustrophobia (fear of closed spaces) or other phobias. When a light anesthesia is administered, a person relaxes and forgets about his complexes. Sedatives do not cause harm, but they work. After all, if the patient moves at an inappropriate moment, the device will produce an image of inadequate quality, which means the examination itself may become impractical.

Feelings after anesthesia

In most cases, after anesthesia and surgery, the patient is transported to the department where he was before the operation. Only in exceptional situations, when the health condition is considered serious or even extremely serious, is he sent to intensive care.

Indeed, after anesthesia and surgical manipulations, the body needs some time to recover. The duration of recovery will be different for each person, because it depends on many factors, such as: duration of anesthesia, complexity of the operation, gender of the patient, his initial condition and characteristics of the body. Usually, a day after anesthesia, the patient ceases to feel the effects of the administration of anesthetics.

In the first minutes after waking up, the patient feels lethargy, disorientation in space, lethargy and rigidity of thinking. It is difficult for a person in this state to concentrate and formulate his thoughts. These sensations may fade and recur, but after a few hours consciousness becomes clearer and clearer.

Some effects of anesthesia last for several hours. Thus, the patient becomes sleepy, feels weak in the muscles, and experiences difficulty coordinating movement. If the patient has undergone spinal anesthesia, then for some time after waking up he will be overcome by severe weakness and a feeling of numbness in the limbs, “pins and needles” in the legs, and a frightening inability to perform any actions. In fact, there is no need to panic, as physical activity will return within a few hours. Let's consider other effects that occur after anesthesia.

Painful sensations

The level of pain relief after recovery from anesthesia rapidly decreases, which means that pain at the operation site increases. The pain can be severe and often leads to increased blood pressure and increased heart rate. You should report your feelings to your doctor or nurse, who will give you an anesthetic injection and help alleviate your condition.

Knowing how long it takes to recover from anesthesia, and what a person who has undergone surgery feels, each patient will be more relaxed about this procedure. Good health to you!

Before the planned operation, in addition to how everything will go, the patient is concerned about one more question: what will the recovery be like after general anesthesia and how to quickly get out of this state? These experiences are quite understandable, because there are often cases when a person reacts quite severely to the drugs administered.

Anesthesia is an artificial sleep caused by certain drugs (anesthetics), during which reflexes and some body functions are inhibited and switched off. The muscles relax, the reaction to pain disappears, and consciousness turns off.

How long does it take to recover after anesthesia?

Almost everyone who is about to undergo surgery asks themselves and doctors this question, but it is unlikely that anyone will be able to answer unequivocally how long the anesthesia takes to wear off and how it is removed. Recovery lasts from a few minutes to a certain number of hours. Therefore, how to quickly recover from anesthesia depends on several factors:

Duration of the operation. If it is complex and lasts several hours, then coming out of anesthesia will be more difficult.
Dosage of anesthetics. It is directly related to the time spent on the operation: with a multi-hour surgical intervention, the amount of the administered drug is correspondingly greater and its tolerability may be more difficult.
General health of the patient. A strong body is able to tolerate anesthesia more easily and recover from it faster.
Patient's age. Older people usually have a more difficult time with anesthesia.

Recovery from anesthesia is accompanied by the restoration of vital processes and the return to functioning of all functions. On average, this takes from 1.5 to 5 hours. The anesthesiologist continues to observe the patient after the intervention is completed, monitoring how the person returns to normal and whether there are any complications.

Possible side effects of anesthesia

How the body will cope with anesthetics and how the patient will recover from their influence is of particular concern to the patient. Everyone has their own reaction to the administered drugs: some come out of this state almost immediately, while others experience side effects:

Headache, dizziness. Anesthetics sometimes lower blood pressure, which leads to dizziness. Head pain is common after an epidural, but it goes away within a few hours.
Sore throat. If you had to use a breathing tube or intubate the patient, then this side effect is possible. Usually goes away within 2 days.
Nausea, sometimes with vomiting. The most common occurrence. The feeling of nausea directly depends on the drugs administered.
Confused consciousness. This usually affects older people.

These are the main, most common side effects of anesthesia. There are several more severe reactions of the body, but they are less common:

hallucinations;
speech or hearing impairment;
chills;
slow thinking;
numbness of the limbs;
sleep disturbance.

In any case, it is not at all a fact that the listed reactions to anesthesia will necessarily occur. Most of them can be avoided if you take into account a number of simple conditions.

General rules: how not to aggravate the effects of anesthesia, prevention

To help yourself and more easily survive the so-called “coming-off” from anesthesia, you need to follow several rules that doctors always warn about:

The day before surgery, you should absolutely not eat heavy foods. Dinner should be light, and no later than 18-19 hours (the doctor will say more precisely, it depends on the type of operation and its expected duration).
On the day of the operation (before the start), you can eat 6 hours (no later), and drink at least 2 hours or more. In each specific case, the possible time of eating will be more accurately determined by the anesthesiologist.
The anesthesiologist must know absolutely everything about the patient’s condition in order to select the correct dose of the drug or cancel the operation. This is especially true in cases where the patient’s well-being suddenly changed shortly before the intervention. It is very important!
You can drink no earlier than an hour later, and only with your doctor’s permission. You should not drink sweet or carbonated drinks: this can cause bloating or vomiting. It is better to drink plain boiled water or warm tea.
If drinking does not cause vomiting, after a few hours, with the consent of the doctor, you can eat some light and liquid food: fermented milk products, cream soup, jelly, vegetable puree. It is especially important to adhere to such a diet for those who have undergone surgery on the abdominal or pelvic region: these patients will experience disturbances in peristalsis for 2-3 days, so the food should be as gentle as possible and made from easily digestible foods.
If the operation was long and difficult, then in order to avoid memory impairment you will need to drink a lot of fluid: from 1.5 to 3 liters per day. This will help remove the drug from the body faster.
There is no point in enduring severe pain in the operated area, so you can always ask the doctor to prescribe a painkiller injection. But usually the patient who wakes up is given an injection immediately.

What anesthesia is indicated for children

MRI with anesthesia for young patients is an even more important procedure. But this is necessary so that nervous conditions do not develop in the future and they do not develop into huge fears. For children, anesthesiologists use short-acting drugs. They are eliminated from the body very quickly, but put the patient into deep sleep. They have practically no contraindications.

The use of tranquilizers in children is prohibited, since their use can significantly affect the functioning of the lungs and cardiac system.

As for the procedure itself, its safety also lies in the fact that patients are connected to a system for monitoring their condition. Doctors can evaluate the well-being and functioning of the organs and systems of the subjects every second.

Prevention of complications

In addition to the sometimes difficult condition after anesthesia, there is also a risk of postoperative complications. But they can be avoided if you follow simple conditions.

After surgery, the patient cannot always breathe deeply, which is usually fraught with depression of respiratory function, congestion in the lungs and subsequent pneumonia. Therefore, in order to catch his breath, the patient needs to perform breathing exercises. An exercise that simulates inflating a balloon will be useful.

2 hours after the surgeon finishes his work, you need to start turning over (with the doctor’s permission), after 5-6 hours you should try to sit up on the bed, and after half a day or a day you can walk. Physical activity is necessary to avoid the formation of blood clots due to a long lying position. Perhaps the doctor will prescribe physical therapy.

Conclusion

The fear of going under the influence of anesthetics is understandable for many people. But this greatest invention gives doctors a unique opportunity to carry out any, even the most complex, operations and other actions without the threat of painful shock in the patient. Drugs that put the patient into a state of artificial sleep are constantly being improved, and perhaps someday a drug will be invented that does not cause negative reactions in the body.

But for now, it is important to understand that there are basic requirements to alleviate your condition after anesthesia:

thorough preliminary examination and compliance with the doctor’s recommendations before surgery;
correct actions after surgery regarding physical activity, breathing and nutrition;
a conversation with an anesthesiologist if there is panic or worsening of the condition before the operation, which will help the specialist select the appropriate drug depending on the health and psychological state of the patient, the anesthesiologist can also advise you how to quickly recover from anesthesia if you ask him about it.

And there is one more very important condition: do not listen to terrible stories about how hard and painfully one of your relatives or friends experienced the “recovery” from anesthesia. Everything will go differently for everyone, and over time, any sensations experienced at this time will still be forgotten.

When the procedure is contraindicated

Before anesthesia is administered for MRI, the patient is examined. Anesthesia should not be given if:

There is developmental delay, weight deficiency, and rickets.
Body temperature is increased.
There are infections.
The patient suffers from asthma.
There are diseases of the nervous system.
The heart is not working well.

Asthma is a contraindication

If the doctor is constantly with the patient during the examination, there will be no threats, even when there are some contraindications.