Is anesthesia dangerous? Expert - about myths and real medical practice

• Myths about anesthesia
• Modern drugs for anesthesia
• Imaging Techniques for the Anesthesiologist
• Liver and brain toxicity
• Consequences of anesthesia for older people
• Epidural anesthesia
• Anesthesia in dentistry

Traditionally, the patient experiences the greatest fear when thinking about general anesthesia.

Let's start dispelling myths with terminology; general anesthesia does not exist in medical nature. After all, translated from Latin, anesthesia is a medicinal sleep, so any manipulation in which our consciousness turns off for at least a minute is called anesthesia. And it is always general, because there is no local sleep. Confusion arises because a synonym for anesthesia is general anesthesia.

Why general anesthesia is dangerous - myths about anesthesia

Over the past decades, general anesthesia has become much “softer”: the introduction of drugs with fewer side effects, a significant reduction in the use of narcotic drugs, the development and active use of a new generation of gas mixtures that enter the lungs through a ventilator and support a person in medicated sleep as much as necessary, all this has led to the fact that modern anesthesia has become practically safe. Proof of this is the fact that these days there is practically no question about the duration of anesthesia. If in the 70s, hours were counted, and the longer a person was in medicated sleep, the worse he “moved away from it,” but now serious operations last for 10–12 hours, and the next day the patient is transferred to a ward, which called “with a clear head.”

Another brick in the safety wall is the active introduction of imaging techniques in anesthesiology. If previously a doctor punctured large vessels and installed catheters in them blindly, based only on anatomical landmarks and his own experience, today everything happens under ultrasound control, the risk of error and the development of complications tends to zero.

The equipment controls the depth of anesthesia, automatically changes breathing parameters, selecting optimal criteria for each specific moment of the operation. The workplace of an anesthesiologist is difficult to distinguish from the cockpit of an airliner.

As you know, in the past, the liver and brain suffered the most from serious anesthetic drugs. Therefore, special attention is paid to neuro- and hepatoprotection. Modern drugs have minimal hepatotoxicity and virtually no damage to the liver, neurotoxicity is also significantly reduced, and special drug regimens are used to protect the brain. And it works, because stories about memory loss or deterioration of brain activity after anesthesia are becoming less and less common.

Science and clinical practice

I will try to tell you about the effect of anesthesia on the human body, and in particular on the brain.

Anesthesia is a state of loss of consciousness that is induced artificially and is characterized by its reversibility. Anesthesia produces pain relief, which allows it to be used in surgery to relieve the patient of the suffering associated with the sensation of physical pain. The state of anesthesia is achieved with the help of anesthetics; there is a certain medical specialization - an anesthesiologist who selects the optimal dose and combination of drugs based on the individual characteristics of the patient’s body, in addition, the type of medical effect matters. It often happens that anesthesia causes fear in people to a large extent more than the surgical operation itself. Among other things, there are many rumors and rumors about anesthesia; some fear that anesthesia can cause death. Is it really? How does anesthesia affect the human body? Is it dangerous, will anesthesia affect further memory problems and cognitive functions of a person?

I don’t want to offend anyone, but very often I hear amazingly illiterate and ignorant statements about anesthesia on this subject, not only from ordinary people, but also from doctors, but almost any non-anesthesiologist will be happy to tell you thoughtfully something like “anesthesia is always anesthesia” or “Anesthesia is not candy.” It’s good that at least the majority do not repeat the generally accepted nonsense that “anesthesia takes 5 years of a person’s life” or “affects the heart.” Patients who undergo operations under general anesthesia write with pleasure in various forums how afraid they are of “general anesthesia,” and a chorus of well-wishers echoes them: “yes, yes, anesthesia is like dying a little,” “anesthesia has a lot of contraindications,” “maybe allergic shock!” It seems that you can do without anesthesia and there is no need to monitor the patient’s somatic condition during the most complex and traumatic interventions. True, no one writes that pain has a very, very strong effect on health, that not everything can be tolerated.

Most of us know about anesthesia that it is used during operations as an anesthetic; this is where our knowledge ends and fears, worries, and speculation begin. General anesthesia, or anesthesia, is a time-limited state of unconsciousness during the administration of special painkillers, during which time the patient undergoes a surgical operation, after which the patient’s consciousness is restored. The actions of the anesthesiologist are aimed at relieving the patient of pain during the operation, as well as to ensure a normal and painless transition to a state of consciousness, with no discomfort.

How general anesthesia affects the human body should be discussed based on what type of anesthesia is used. General anesthesia is divided according to several criteria, but again we will not go deeper, but will only name and characterize the main types used in practice. For major operations on internal organs located above the diaphragm, which separates the chest cavity from the abdominal cavity, anesthesia with artificial ventilation of the lungs is usually used, and, in heart operations, with artificial circulation. Anesthesia drugs can be administered either intravenously or through inhaled air, or both. Sometimes such anesthesia is also supported by spinal (subdural) or epidural anesthesia, which, in turn, can be used independently. During spinal anesthesia, the drug is injected under the dura mater into the fluid that washes the spinal cord at the level of its segments responsible for sensitivity in the surgical area. For the duration of the anesthetic, these segments and all those located below them become insensitive to pain, and the anesthetized parts of the body become immobile. With epidural anesthesia, the drug that causes it is injected above the dura mater, at the level of the nerve trunks extending from the spinal cord and, washing them, causes an interruption of sensory and motor nerve impulses at the site of action of the drug. Organs located below the operation site may not be anesthetized. Both types of such anesthesia are considered gentle: they are the least aggressive and have the advantages of general and local anesthesia, while practically not having their disadvantages. Epidural anesthesia can also be prolonged. In this case, a thin catheter (tube) is placed over the dura mater and brought out. It is glued to the patient’s back and painkillers are added there: this postoperative pain relief is the most effective. These types of anesthesia require a very small amount of a drug from the group of local anesthetics; until recently, pain relief was done with lidocaine, but now drugs have been proposed that act longer and are more effective in smaller doses.

The anesthesiologist chooses the type of anesthesia based on the individual characteristics of the person being operated on; the choice depends on his physical condition, on what kind of operation is being performed, and even the level of qualification of the surgeon and the anesthesiologist himself matters. In order to perform the same operation on different people, different types of anesthesia can be applied to them; the ideal combination of drugs is selected for the patient, which is achieved by mixing different drugs and types of pain relief. Thus, the importance of a specialist anesthesiologist is extremely difficult to overestimate; this doctor is always present during all major operations.

People who have undergone surgery, and therefore general anesthesia, report the following symptoms and unpleasant moments after the use of painkillers:

Firstly, memory impairments are possible, which can manifest themselves in different ways, from subtle isolated cases to regular and pronounced ones that arise suddenly.

Secondly, after using anesthesia, some note sleep disturbances, which can persist even several months after the operation.

Thirdly, immediately after surgery, the use of anesthesia can cause headaches, hallucinations, hearing and speech disorders. All these symptoms, as a rule, disappear within the next few hours after the application of anesthesia.

And this is not a complete list of troubles that can be caused by the use of anesthesia, as people who have suffered it say.

Now let's talk about the effect of general anesthesia on the brain:

Some of the consequences of anesthesia are memory impairment, decreased attention, and deterioration in learning ability. The disorders described above in medicine are called postoperative cognitive dysfunction. Memory impairments observed after anesthesia always cause a lot of trouble for patients. Patients are concerned about what happened to their memory after anesthesia, how long it will last, and what can be done to alleviate the condition. As a rule, anesthesiologists cannot give clear answers to the questions posed above. Memory impairment after anesthesia is not such a rare complication. Most studies regarding post-anesthesia memory impairment have focused on cardiac surgery. It has been shown that during the first week after anesthesia, memory impairment occurs in 30-80% of cardiac surgery patients. Patients who have undergone non-cardiac surgery are at slightly lower risk of developing memory impairment after anesthesia. Thus, in the first week after anesthesia, a decrease in memory and attention is observed in 25% of patients, and after 3 months – in 10% of patients. There are studies that show that after undergoing anesthesia, cognitive disorders can persist for a year or more.

Scientists have not reached a consensus on which type of anesthesia has the least effect on the brain. According to some, disorders of cognitive functions such as memory, attention and learning occur with the same frequency, both with general anesthesia and with regional methods of anesthesia (spinal anesthesia; epidural anesthesia). Others have concluded that regional anesthesia is associated with fewer incidents of memory and attention impairment.

There is no clear answer regarding the harmfulness or harmlessness of individual anesthesia drugs. It is believed that sharp changes in the delivery of oxygen to the brain are important in the development of memory impairment during anesthesia. During anesthesia, it is possible to develop certain conditions that are associated with the development of temporary oxygen starvation of the cerebral cortex. These conditions are associated with a significant drop in blood pressure and a marked decrease in oxygen levels in the blood.

Despite the fact that the causes of post-anesthesia intellectual impairments continue to remain unclear, scientists have found a number of factors that increase the risk of developing attention and memory impairments after anesthesia: older age, repeated anesthesia, long-term surgery, low level of education of the patient, and those that developed after surgery. infectious and respiratory complications.

In order not to scare potential patients, as a neurosurgeon I can say that often all problems with memory and cognitive functions are reversible! There is a sufficient arsenal of tools to solve this issue, which in most cases will help not lead to the development of complications or will help restore lost functions as quickly as possible.

The most important thing I want to say in conclusion is that, of course, the risk of anesthesia and the volume of surgical intervention are always assessed. You always need to make a CHOICE!

The choice is of course yours, but after an explanation from the TEAM (anesthesiologist and surgeon) about the development of possible pros and cons - and the occurrence of possible complications.

By the word TEAM I mean a well-coordinated team (anesthesiologist, surgeon, nurses) who work in one direction - for the benefit of the patient with a good quality of life!

Epidural anesthesia

Many operations take place while the patient is conscious. For example, operations on the lower extremities, genitals, hernias, and many others. Mainly due to the use of various types of spinal anesthesia, mainly epidural block. In this case, for pain relief you will need several milliliters of the drug, which are injected into the epidural space running along the spinal column. But for several hours, the absence of sensitivity below the level of the catheter is guaranteed.

Childbirth is increasingly taking place under epidural anesthesia. But we must remember that it is not recommended in cases of weak labor, when contractions, on the contrary, have to be stimulated. As for the situation when childbirth proceeds normally, data from many years of research indicate that epidural anesthesia during childbirth is safe and effective.

Today, many people prefer to undergo unpleasant examinations under general anesthesia - gastro- and colonoscopy, various biopsies and punctures. This is really a solution for those who are very afraid of even a little pain and do not want to experience painful minutes. The main thing is that the procedure is carried out under the supervision of an anesthesiologist, who accurately calculates the dosage of the drug and turns off consciousness to the minute. He monitors the patient's breathing and, if necessary, adds a little medicine. If these rules are strictly followed, studies under intravenous general anesthesia are absolutely safe.

Side effects

Nausea is a common side effect of general anesthesia.

There are a number of potential side effects of anesthesia.

Some people may experience none, others several. None of the side effects are particularly long-lasting and usually occur immediately after anesthesia.

Side effects of general anesthesia include:

• temporary confusion and memory loss, although this is more common in older people
• dizziness
• difficulty urinating
• bruising or soreness from the IV
• nausea and vomiting
• trembling and chills
• sore throat due to breathing tube

Anesthesia in dentistry

And one more question that interests many: is it worth agreeing to general anesthesia when installing dental implants? In fact, in this case there is no choice. After all, if we are talking about installing 1-2 implants, you can really get by with local anesthesia, but when a dentist does half of the jaw at a time, then working without anesthesia will turn into real torture for both the doctor and the patient. Considering these facts and the safety of modern anesthesiology, most patients agree with the doctor’s proposal and prefer to wake up with a finished result.

Story

General anesthetics have been widely used in surgery since 1842, when Crawford Long prescribed diethyl ether to a patient and performed the first painless operation.

On October 16, 1846, American dentist and surgeon Thomas Morton first administered ether anesthesia to a patient to remove a submandibular tumor.

In Russia, the first operation under anesthesia was performed on February 7, 1847 by Pirogov’s friend at the professorial institute, Fyodor Inozemtsev.

Pirogov himself performed the operation using anesthesia a week later. Over the course of a year, 690 operations were performed under anesthesia in 13 cities of Russia, 300 of which were performed by Pirogov!

Soon he took part in military operations in the Caucasus. Here, for the first time in the history of medicine, he began to operate on the wounded with ether anesthesia. In total, the great surgeon performed about 10,000 operations under ether anesthesia.

Risks

In general, general anesthesia is safe. Even very sick patients can be safely anesthetized. The surgical procedure itself involves much greater risk.

Modern general anesthesia is an incredibly safe procedure.

However, older adults and those undergoing lengthy procedures are most at risk for complications . These findings may include postoperative confusion , heart attack, pneumonia, and stroke.

Some specific conditions increase the risk for a patient undergoing general anesthesia, for example:

• obstructive sleep apnea, a condition in which people stop breathing while sleeping
• seizures
• existing heart, kidney or lung disease
• high blood pressure
• alcoholism
• smoking
• previous negative reactions to anesthesia
• medications that may increase bleeding - aspirin, warfarin , for example
• drug allergy
• diabetes
• obesity or overweight

Preoperative assessment

Before undergoing general anesthesia, patients should undergo a preoperative assessment to determine the most appropriate medications, their amount and combination.

Some of the factors that should be examined in the preoperative assessment include:

• body mass index (BMI)
• disease history
• age
• medications taken
• time before anesthesia
• alcohol or drug use
• use of pharmaceuticals
• examination of the oral cavity, teeth and respiratory tract
• cervical spine mobility study

It is important that you answer these questions accurately. For example, if a history of alcohol or drug use is not mentioned, insufficient anesthesia may be given, which could lead to dangerously high blood pressure or unintentional intraoperative awakening.

Unintentional intraoperative awakening

This refers to rare cases where patients report remaining conscious during surgery, long after the anesthetic should have taken effect . Some patients are aware of the procedure itself, and some may even feel pain.

Unintentional intraoperative awakening is incredibly rare, affecting approximately 1 in every 19,000 patients under general anesthesia.

Because of the muscle relaxants used at the same time as anesthesia, patients are unable to let their surgeon or anesthesiologist know that they still know what is happening.

Unintentional intraoperative awakening is more likely during emergency surgery.

Patients who experience unintentional intraoperative awakening may suffer from long-term psychological problems. Most often, awareness is short-lived and only sounds, and occurs before or at the very end of the procedure.

According to a recent large-scale study of this phenomenon, patients experienced involuntary twitching , stabbing pain, pain, paralysis and suffocation, among other sensations.

Because unintentional intraoperative awakening is rare, it is unclear exactly why it occurs.

Stages

The Gödel classification, developed by Arthur Ernest Gödel in 1937, describes four stages of anesthesia. Modern anesthetics and updated methods of drug have improved the speed of onset of anesthesia , overall safety and recovery, but the four stages remain essentially the same:

General anesthesia is similar to a comatose state and different from sleep.

Stage 1 or induction . This phase occurs between the administration of the drug and loss of consciousness. The patient moves from analgesia without amnesia to analgesia with amnesia.

Stage 2, or arousal stage . The period after loss of consciousness, characterized by agitated and delirious activity. Breathing and heart rate become erratic, and nausea, dilated pupils, and holding your breath may occur.

Due to irregular breathing and the risk of vomiting, there is a danger of suffocation. Modern fast-acting drugs are aimed at limiting the time spent on the 2nd stage of anesthesia.

Stage 3 or surgical anesthesia : muscles relax, vomiting stops, breathing is suppressed. Eye movements slow and then stop. The patient is ready for surgery

Stage 4, or overdose : if too much anesthetic has been administered, then depression of the brain stem occurs . This leads to respiratory and cardiovascular collapse.

The anesthesiologist's priority is to get the patient to stage 3 anesthesia as quickly as possible and keep him there throughout the operation.

Local vs General

There are a number of reasons why general anesthesia may be chosen over local anesthesia.

This choice depends on age, health and personal preference.

The main reasons for choosing general anesthesia are:

• The procedure will likely take a long time.
• There is a possibility of significant blood loss.
• This may affect breathing, for example during breast surgery.
• The procedure will make the patient feel uncomfortable.
• It is difficult for the patient to maintain a forced position during surgery.

The purpose of general anesthesia is to induce:

• pain relief or elimination of the natural response to pain
• amnesia or memory loss
• immobility or elimination of motor reflexes
• dream
• relaxation of skeletal muscles

However, the use of general anesthesia poses a higher risk of complications than local anesthesia. If the surgery is minor, then the patient is offered local anesthesia, especially if he has a condition such as sleep apnea or other risk factors.