What Is Anesthesia?

It is generally believed that anesthesia is a reversible functional depression of the central nervous system and / or peripheral nervous system produced by drugs or other methods. This suppression is mainly characterized by the loss of sensation, especially pain.

Does anesthesia affect intelligence?

Many people wake up after surgery and feel chaotic, so they often worry that anesthesia will harm their intelligence. As a result, many patients have a negative attitude towards anesthesia. So, does anesthesia really affect intelligence?

The principle of anesthesia is more

The reason why anesthesia can eliminate pain is that anesthetics block the signal transmission of pain, the brain can't receive the pain signal, or it can temporarily "numb" the brain, so that we can't feel pain all over the body.

Are there any side effects from anesthesia? More

At present, the safety of anaesthetic drugs applied to the clinic is very high. It has no effect on young adults who have a well-developed brain; it may have effects on children and the elderly whose central nervous system is developing or degenerating. After undergoing major surgery, some elderly people will have a decline in learning ability and memory to a certain extent in a short period of time, and can recover after a few days, and a very small number of people can not even recover for months or even permanently.

Content organization: du Xiaoli

Basic Information

English name

anesthesia

Visiting department

Department of Anesthesiology

Common symptoms

Loss of pain

Contagious

no

Development stage of anesthesia

1. The development stage of ancient anesthesia--the discovery and bud of anesthesia

From the prehistoric period, the development of ancient medicine has gone through a long time. In labor and life, human beings are constantly looking for medicines and methods to reduce the trauma or pain caused by disasters or animals. "Shen Nong tastes Baicao and encounters 70 poisons in one day" reflects that the ancient people of our country have been doing everything possible to find good medicines for curing diseases and pain. During this period, natural plant drugs such as opium, marijuana, and mandela appeared to be used for analgesia, but from the perspective of the concept of anesthesia, regardless of its anesthetic effect and safety, it is incomparable with modern anesthetic drugs and methods. In a budding state.

2. The development stage of modern anesthesia-the formation of clinical anesthesia

From the 18th century, general anesthesia such as ether was successfully used in surgery, and it was the beginning of modern anesthesia. This stage is characterized by many medical scientists, chemists, including surgeons, medical students, etc. who have contributed to the discovery and clinical application of anesthetics. At the same time, the clinical application of anesthesia methods and drugs is diversified. Aiming at the problems during surgical anesthesia, it has also developed from simple analgesia to a more comprehensive treatment during and after anesthesia. By the 1930s and 1940s, it had accumulated rich clinical experience and gradually formed clinical anesthesia.

3. Developmental stages of modern anesthesia

In the 1950s, based on the development of clinical anesthesiology, the scope and fields of anesthesia were further expanded. The basic theory and professional knowledge of anesthesia were continuously enriched and improved. The anesthesia operation technology was continuously improved and improved. The anesthesia discipline and specialty were further developed. . Entered the third stage of the development of modern anesthesia. This stage is characterized by the emergence of a large number of professionals engaged in anesthesia. Due to the expansion of the scope and field of anesthesia, anesthesia branched out into subdisciplines. With the use of new theories, new knowledge, and new technologies, anesthesia was promoted. Modernization of learning.

The scope of modern anesthesia

It mainly includes 4 aspects:

Clinical anesthesia

All treatments involving perioperative period before and after anesthesia. Make preparations before anesthesia, such as understanding the condition, and selecting the most appropriate anesthesia and medicine in conjunction with surgery. In order to reduce the patient's mental stress before surgery and ensure the smooth progress of anesthesia and surgery, sedatives, analgesics, anticholinergics and other anesthetic drugs can be given appropriately. Fast before anesthesia to prevent complications such as vomiting and aspiration during surgery. After receiving the operating room, the patient was anesthetized according to the operating requirements. During anesthesia and surgery, we must closely observe the changes of the patient and carry out necessary treatment. After anesthesia, the patient is safely transported back to the ward or anesthesia recovery room, and monitoring and treatment are continued until the patient recovers normal physiological functions. Make anesthesia records during and after anesthesia.

2. Intensive care

Critically ill patients or patients with serious complications during anesthesia surgery, such as those with severe functional disturbances in circulation, breathing, nerves, liver, kidneys, metabolism, etc., can be concentrated in intensive care units that focus on precision and valuable equipment. Professionally trained medical personnel perform thorough and sophisticated monitoring and treatment, and the anesthesia profession plays an important role in it, participating in shock treatment and respiratory therapy.

3. Emergency Resuscitation

During the anesthesia of the operation, heartbeat and respiratory arrest will suddenly occur. Circulation and respiratory failure (such as diseases, trauma, drowning, electric shock, traffic accidents, etc.) that may also occur in the emergency room and ward due to various reasons, require immediate heart Pulmonary resuscitation, at this time, anesthesia workers need to participate in rescue.

4. Pain treatment

For a variety of acute and chronic pain (such as post-traumatic pain, waist and leg pain, neuralgia, tumor pain, central pain).

Clinical anesthesia

Including general anesthesia and local anesthesia.

General anesthesia

General anesthesia refers to the process of injecting anesthetics into the body through inhalation, intravenous, intramuscular injection or rectal injection, so that the central nervous system is inhibited, causing the patient to lose consciousness without pain throughout the body. This type of anesthesia is the commonly-known "sleeping state", which is characterized by the disappearance of the patient's consciousness, the relaxation of muscles throughout the body, and no pain. The most common type of general anesthesia is tracheal intubation. It is characterized by the use of intravenous or inhaled anesthetics to produce general anesthesia. Intraoperative tracheal intubation and mechanically assisted breathing are required.

The process of tracheal intubation under general anesthesia. This process includes anesthesia induction, anesthesia maintenance, and anesthesia recovery. The so-called anesthesia induction is to make people from awake to falling asleep. After the patient enters the operating room, the nurse first opens the venous access (that is, a needle infusion), the anesthesiologist connects the monitoring of ECG, blood pressure, blood oxygen saturation, etc., and the mask inhales oxygen. The anesthesiologist can then begin induction of anesthesia. The anesthesiologist will give the patient an intravenous general anesthetic or inhale the anesthetic gas. The patient's consciousness disappears 3 to 5 minutes after the administration, and the patient will go from sleep to awake. Under general anesthesia, because of unconsciousness and general muscle relaxation, the patient loses breathing power and spontaneous breathing usually disappears. Therefore, after the patient enters the general anesthesia state, the anesthesiologist will perform tracheal intubation operation, that is, laryngoscope, etc. With the aid of a tube instrument, a tracheal tube is inserted into the patient's trachea through the patient's mouth or nasal cavity. The other end of the tracheal tube is connected to an anesthesia machine, which delivers oxygen to the patient through the tracheal tube to help the patient breathe.

After that, it will enter the state of anesthesia maintenance. The anesthesiologist will continuously inhale the anesthesia gas to the patient through the anesthesia machine, or continue infusion of anesthesia drugs through the intravenous access, so that the patient is continuously under anesthesia. At this point, surgery can begin. The length of the entire anesthesia maintenance period depends on the length of the operation. The longer the operation time, the longer the anesthesia maintenance time; the shorter the operation time, the shorter the anesthesia maintenance time. When the operation is successfully completed, the anesthesiologist will stop using the anesthetic and the patient will enter the anesthesia recovery period. With the metabolism of anesthetic drugs in patients, the concentration of anesthetic drugs gradually decreases. When the concentration of anesthetic drugs in the body is reduced to a certain level, the patient can resume spontaneous breathing, and his consciousness will be clear. At this time, the anesthesiologist will pull out the tracheal tube, continue to inhale oxygen to the patient, and suck out oral secretions. When the patient's spontaneous breathing recovers well, his consciousness is fully awake, his ability to perceive is good, and his vital signs are stable, that is, when he has reached the anesthesia recovery standard, he can return to the ward.

General anesthesia does not always require intubation and mechanical ventilation. Some time is short, no harmful stimuli, simple surgical operations and inspection operations, such as abortion surgery, gastroscopy, etc., do not require tracheal intubation and general anesthesia, but can implement general anesthesia that retains spontaneous breathing but disappears .

Local anesthesia

Local anesthesia is the use of local anesthetics such as procaine, lidocaine, etc., injected at the corresponding site to block the spinal nerve, plexus or nerve trunk and finer peripheral nerve endings. . The characteristic of local anesthesia is that the anesthesia is limited to the "local" of the body, and the patient's consciousness is sober. Common methods include spinal anesthesia (block), nerve block, regional block, local infiltration anesthesia, and surface anesthesia.

Spinal canal anesthesia is a local anesthetic injected into the spinal canal through spinal puncture. The subarachnoid space is called subarachnoid block or spinal anesthesia, and the epidural space is called epidural. Lumen block. Spinal canal anesthesia is also commonly known as "half body anesthesia". The anesthesiologist will perform an operation on your back, and then you will feel numbness in the lower body, and the pain and touch will disappear.

Nerve block is the injection of a local anesthetic into a nerve trunk (plexus) of the body, causing painful conduction block in the area it controls. Common nerve blocks include cervical nerve plexus block, brachial plexus block, femoral nerve block. Blocking and so on.

Regional block is the injection of a local anesthetic around the surgical site to block nerve endings in the surgical area to achieve the purpose of anesthesia.

Local infiltration anesthesia is a method of injecting local anesthetic directly into the surgical site and distributing it evenly throughout the layers of the entire surgical area to block the transmission of pain.

Surface anesthesia is to spray or apply a highly permeable local anesthetic to the surface of the mucosa, conjunctiva, etc. to produce anesthesia.

Clinical Anesthesia Application

Many anesthesiologists don't know much about the work of the general public, but simply think that the anesthesiologist just needs a shot of anesthesia before the operation is okay. In fact, in addition to the work of anesthesiologists, in addition to ensuring that patients undergo surgery successfully under painless and safe conditions, they also include preparation and treatment before and after anesthesia, monitoring and treatment of critically ill patients, emergency resuscitation, and pain treatment.

In order to do a good job of clinical anesthesia, it is necessary to master the basic theory of anesthesia and skillfully apply various anesthesia techniques and operations, and also to be familiar with the characteristics of various conditions of surgery. In each case of anesthesia, the following specific tasks must be performed.

1. Preparation before anesthesia

It is mainly to understand the condition, make a correct estimate, determine the anesthesia plan in combination with the condition, and select the most appropriate anesthesia method and medicine. Fully estimate the problems that may occur during anesthesia surgery, in order to prevent problems before they occur, make adequate preparations and preventive measures, and formulate treatment plans for possible problems.

2. Work during anesthesia

Perform anesthesia according to the anesthesia operation protocol to obtain the best anesthesia effect, so that the patient can complete the operation without pain, quietness, no memory, and no adverse reactions. At the same time, create good conditions for surgery, and try to meet the special requirements of certain surgery (such as muscle relaxation, low temperature, low blood pressure, etc.). Do a good job of monitoring the surgical anesthesia process, including continuous monitoring of circulation, breathing, water electrolyte, body temperature and other functions, and write down anesthesia records. According to the changes of the anesthesia process, effective treatments are made, such as maintaining hemodynamic stability and performing respiratory management.

3. Work after anesthesia

After the anesthesia, return the patient to the ward (or anesthesia recovery room) for a good transfer. According to different conditions and operations, do a variety of treatments after anesthesia, including continuous monitoring of patients, prevent complications, deal with accidents in a timely manner, and assist clinical departments to treat complications, so that patients can recover as soon as possible. Make a record of follow-up and summary after anesthesia.

4. Anesthesia recovery room and enhanced monitoring and treatment room work

With the increase of complex anesthesia and surgery performed by critically ill patients, the end of surgery does not mean the disappearance of anesthesia and the complete recovery of main physiological functions, plus the disturbances of circulation, breathing, metabolism and other functions that have occurred during surgical anesthesia. Failure to completely correct it, there is still the danger of various complications after anesthesia. Patients after anesthesia surgery still need to be carefully treated by professionally trained medical staff to promote early recovery. As a result, anesthesia recovery rooms and enhanced monitoring treatment rooms were established. Anesthesiologists play an important role in the recovery of anesthetized patients, the monitoring of critically ill patients, and the prevention and treatment of anesthesia complications.

5. Emergency Resuscitation

Anesthesiologists make full use of the acquired professional knowledge and techniques, such as endotracheal intubation, artificial ventilation, cardiopulmonary resuscitation and other methods, and participate in emergency resuscitation treatment in hospitals, playing an important role in emergency resuscitation.

6. Pain treatment

Anesthesiologists can control and treat acute and chronic pain by using analgesics and nerve block technology mastered by anesthesia specialty, and open pain treatment clinics or wards. It plays an important role in the treatment of postoperative analgesia, painless delivery and advanced cancer pain.

In short, the clinical anesthesiologist is mainly responsible for: jointly determining with the patient's doctor whether the patient can withstand surgical anesthesia; deciding which type of anesthesia and monitoring measures; applying anesthesia to the patient; making every effort to ensure the safety of the patient throughout the operation; After the operation is completed, the patient is recovered safely and smoothly; postoperative pain treatment; chronic pain treatment.

Anesthesia Safety and Risk

Anesthesiologists are often asked about "safety and risk of anesthesia" when visiting patients before surgery. In fact, any surgery and anesthesia have certain risks. The level of risk is determined by various factors such as the physical condition of the patient, the type of surgery, and the technical experience and conditions of the medical unit.

1. Physical condition of the patient

The American Association of Anesthesiologists (ASA) has formulated the "ASA Physical Condition Classification" based on the patient's general health and disease severity. Generally speaking, I and II patients have a good tolerance to anesthesia, and the anesthesia is stable. Class III patients have certain risks of receiving anesthesia. They should be fully prepared before anesthesia. Effective measures must be taken to prevent complications. The anesthesia risk of patients with grades IV and V is extremely high, and full and careful preparation before anesthesia is needed. Overall, the worse the patient's body, the higher the risk of anesthesia.

ASA physical condition assessment rating
Grading	standard
I	Physically healthy, well-developed and nourished, and normal function of all organs.
	In addition to surgical diseases, there are mild comorbidities, and functional compensation is sound.
	Coexisting diseases are more serious and physical activity is limited, but they can still cope with daily activities.
F	The comorbidities are severe, the ability to perform daily activities is lost, and life-threatening is often faced.
	With or without surgery, life is difficult to sustain for 24 hours in dying patients.

2. The type of surgery

The risk of perioperative surgery varies in different parts of the surgery. Superficial surgery, such as limb fracture repair, has a much lower perioperative poor prognosis than those with thoracic, abdominal or intracranial surgery. The degree of urgency of surgery is another influencing factor. The congenital nature of the two types of surgery is different when performing emergency or elective surgery. Due to the urgent condition of the emergency surgery, the poor prognosis can be 3-6 times higher than that of elective surgery.

3. Technical experience and conditions of medical units

The technical experience of doctors needs to be accumulated, and the equipment conditions of the units are not the same. The more patients with poor physical condition, many comorbidities, and critical illnesses, the more complicated and difficult the operation, the higher the risk of surgical anesthesia, and the higher the technical experience and conditions of medical units.

In actual clinical work, the anesthesiologist usually visits the patient before the operation. During the visit, the anesthesiologist will understand the patient's current medical history and past history in detail, and make full use of the patient's general condition and important organ physiological functions. Evaluation of the patient's tolerance to anesthesia and surgery. Due to individual differences and comorbidities, anesthesiologists will fully inform patients and their families of the risks associated with anesthesia, and explain relevant anesthesia precautions to patients and their families. And signed an informed consent form.

Medical science is not perfect science, and medical risks inevitably exist in medical practice. Fortunately, the development and improvement of modern medicine has greatly improved the safety of anesthesia. At the same time, in order to ensure that anesthesiologists provide safe and effective treatment to patients, many regions have formulated corresponding anesthesia quality control standards to ensure the quality and safety of anesthesia. Including inspection, preparation before anesthesia, basic anesthesia monitoring, monitoring and treatment during anesthesia recovery. And continue to develop new standards to further increase patient safety. These new industry standards and today's complex monitors and anesthesia equipment, together with evolving medical technology, make patients' lives safer. ^[1-3]