Anesthesia

The anesthesia, or the general anesthesia is the artificially caused condition of the central nervous system which is reversible at which there is a loss of control over some reflexes, relaxation of skeletal muscles, anesthesia, amnesia, a dream and a loss of consciousness. This state comes at administration of several or one anesthetics which optimum combination and a dose is selected individually the anesthesiologist taking into account specific features of the patient, and also depending on medical procedure.

Main goal of an anesthesia is delay of reaction when carrying out an operative measure, first of all for blocking of pain. Medication sleep which usually is associated with this concept is only its compound component. Considerable decrease or full suppression of expressiveness of vegetative reactions of a human body to a surgical injury is also important at an anesthesia. It is characterized by the increased arterial pressure, and also other phenomena taking place at the switched-off consciousness. This suppression of reactions is called an analgesia or anesthesia. There is also the third component of an anesthesia – relaxations of muscles, or muscle relaxation that is necessary for ensuring work of surgeons.

The main priority of an anesthesia is pain and fight against pain: if there is no pain, there will be no start of physiological mechanisms also. Thus, the main protection of the anesthesiologist is prevention of such succession of events.

The concept "anaesthesia" is understood as only the general anesthesia. In case of local suppression of pain, speak about "local anesthesia" or "local anesthesia". Thus, characteristic feature of an anesthesia is switching off of consciousness therefore "anesthesia" and "anesthesia" have absolutely different values.

The first anesthetizing drugs were made already long ago when for these purposes various plants were used: henbane, hemp, opium, etc. Such drugs were used in the form of broths, infusions or sleepy sponges. The last represented sponges which impregnated with juice of certain plants and set fire then patients breathed their smoke.

Types of an anesthesia:

  • Parenteral (intramuscular, intravenous, rectal and so forth)
  • Inhalation
  • Combined (consecutive use of drugs, and also ways of their introduction).

Also distinguish an anesthesia with spontaneous breath, that is with independent, and an anesthesia with artificial ventilation of the lungs. The last is combined, as a rule, with a trachea intubation – introduction of a special tube to respiratory tracts after backfilling of the patient, and also with other methods which provide an opportunity to blow oxygen, air or gas mixes to the patient into lungs with use of a special bag or the medical ventilation apparatus.

Current of an anesthesia

The current of an anesthesia means several stages, each of which is characterized by the features and involvement in process of braking of some structures back and a brain.

At the first analgetic stage there is a condition of the expressed devocalization. Pulse becomes frequent, breath rhythmical and deep, eyeballs move randomly, the tone of muscles is a little raised, reflexes remain kept, pain disappears or becomes dull. The analgesia develops as a result of switching off of the centers of sensitivity of pain in visual hillocks and trunk part of a reticular formation, and activity of a cerebral cortex increases.

At continuation of introduction of means there comes deepening of its effect therefore there comes the following stage – motive excitement which is characterized by chaotic reduction of extremities, increase of a tone of skeletal muscles, nekordinirovanny movements in space and attempts to rise, pulse and breath continue to remain uniform, the blood pressure raises, the pupil extends, and eyeballs "wander", there is often a swallowing, secretion stalemate, bronchial, the lacrimal and sialadens amplifies. There is a deepening of an analgesia. Fibrillation of ventricles of heart, a reflex apnoea, vomiting, an urination, and even death are possible.

Further there comes the stage of a surgical anesthesia. It is divided into 4 levels in anesthesiology:

  • The superficial anesthesia at which there is a total disappearance of tactile and painful sensitivity, narrowing of pupils, pulse increase stabilization of a blood pressure, breath remains deep, rhythmical, begins to snore a little as a result of relaxation of phonatory bands.
  • For an easy anesthesia relaxation of skeletal muscles is peculiar, pulse and breath remain rhythmical, and the anesthesiologist can give to the surgeon a signal of a possibility of the beginning of superficial operation.
  • At a full anesthesia breath still remains superficial and equal, pulse and a blood pressure decrease a little. Reflexes and cavities and body surfaces are not shown, but the centers of blood circulation and breath work normally, pupils begin to extend. Weakening of reflexes of a rectum and bladder, loss of language, and also asphyxia if it is not recorded, because of closing with language of passing to an air throat is possible.
  • The state on the verge of life and death can arise in case of approach of a deep anesthesia. The blood pressure strongly decreases, as well as pulse which becomes weak, small filling. Breath is tolchkoobrazny, superficial, phrenic. Cyanosis of mucous is observed, there are no manifestations of eyeglobes, the pupil extends, and the cornea becomes dry.

Control of a state during an anesthesia

Continuous check of pulse, content of oxygen in blood, the arterial pressure which changes automatically is necessary for successful control of a condition of the patient during an anesthesia or manually in the direct and indirect ways, the ECG, temperature of a surface and "kernel" of a body, gases in blood, diuresis speed, an acid-base state and electrolytic structure continuously is registered.

Special devices support an inhalation anesthesia at the necessary level. It is possible to distinguish rotameters, evaporators which give the chance precisely to define and regulate concentration of gaseous means and vapors of the liquid anesthetics used an anesthesia in respiratory mix from such devices. Besides, these devices allow to control parameters of artificial ventilation of the lungs, and modern devices – even concentration of gases in the exhaled and inhaled air.

Absolute contraindications for an anesthesia are the following states:

  • Acute drug or alcoholic intoxication;
  • State after disturbance of blood circulation or a heart attack before half a year;
  • Acute form of asthma;
  • Disturbances of a cordial rhythm;
  • Heavy pathologies of endocrine system and internals, generally dekompensirovanny;
  • Existence of the diseases depending on hormones.

Besides, it is necessary to warn the anesthesiologist about all accepted medicines and even vitamins, allergies and any diseases sluchayemy earlier.

The anesthesiologist is the specialist doctor who is carrying out an anesthesia. He ensures safety of life, constantly and continuously monitors work of all bodies and functions of an organism, reacts to the arising changes. The limit trust to the anesthesiologist and implementation of all its recommendations is guarantee of successful course of an anesthesia on which also the result of the operation, and also safety of life in many respects depends.

Section: N