ANAESTHESIA (narcosis; grech, nerke catalepsy, numbness +-osis; synonym general anesthesia) — the deep sleep (reversible oppression of cells of the central nervous system) which is artificially caused in the pharmacological or electric way followed by switching off of consciousness, an analgesia, relaxation of skeletal muscles and oppression of reflex activity. In initial value the term «anaesthesia» meant catalepsy.
- 1 History
- 2 Theories of an anesthesia
- 3 Types of an anesthesia
- 4 Anesthetics
- 5 Components of an anesthesia
- 6 Indications to an anesthesia
- 7 Technique of an anesthesia
- 8 The clinical picture of an anesthesia
- 9 Adequacy of an anesthesia (control methods)
- 10 The anesthesia in the emergency surgery
- 11 An anesthesia in children's surgery
- 12 the Anaesthesia at advanced and senile age
- 13 The anesthesia in field
- 14 From additional materials
Anesthesia by means of various stupefying means (a mandrake, a belladonna, opium, the Indian hemp, etc.) was known in Ancient Egypt, India, China, Greece and Rome. Much later (in 13 — 15 centuries) the analgesic effect of alcohol, and also mix of opium with Scopolaminum was open, to-rye along with use in the medical purposes gave to criminals before an execution. However scientific history H. begins only in the middle of 19 century when for several years (from 1842 to 1847) Longum (Page W. Long), H. Wells, U. Morton, J. Simpson, F. I. Inozemtsev and N. I. Pirogov independently from each other begin to test as anesthetics at various operations at first ether and chloroform, and then record of nitrogen, applying them in the inhalation way. Further the general anesthesia by ether, chloroform and nitrous oxide began to be applied widely and allowed to carry out operations impossible before. Discovery by S. P. Fedorov and N. P. Kravkov in 1904 of the anesthetizing properties of the gedonal entered intravenously served as the beginning of development of methods of not inhalation N., to-ry widely apply in modern practice, using barbiturates, steroid anesthetics, hydroxybutyrate of sodium, Epontolum, etc. Intravenous N. supplements inhalation, and it is widely used for bystry introduction to N. and along with it continues to be developed as samostoyatelnyymetod. 50 — the 60th 20 century were marked by opening and implementation in a wedge., to practician of new inhalation anesthetics, among to-rykh galoidsoderzhashchy substances (Trilenum, a halothane, metoksifluran and etran) take the central place. Use of muscle relaxants, analgetics, neuroleptics, and also combinations of anesthetics with various properties opened an opportunity to receive and strengthen the necessary effects of anesthesia, at the same time whenever possible avoiding adverse and toxic effect of each of the used substances. So the method of the combined anesthesia arose.
Pharmakol, researches of the 60th led to opening and implementation in a wedge, practice of substances with narrowly targeted action — powerful analgetics, neuroleptics, and also substances with multifocal type of action, big and small tranquilizers, sedative drugs, to-rye began to apply widely and successfully in anesthesiology. Use of numerous means for N. in combination with razvity methods of artificial ventilation of the lungs and an intensive care provided opportunities for further development of surgery.
Theories of an anesthesia
throughout all scientific history H. became numerous attempts to create the uniform theory of N. which is well explaining the mechanism of its emergence. The assumption that the mechanism of action of all known means is almost identical to N. as the effect caused by them, one and that it was the cornerstone of almost all theories of N. Also attempts to reveal the general for all means used for N., physical, physical became. - chemical or chemical properties or features of a structure, in connection with to-rymi they are capable to cause the general anesthesia. Attempts these were not crowned with success and have only historical interest now. Nevertheless results of these researches and the separate established provisions are originally scientific and exert impact on modern ideas of mechanisms H. and its entities. Indisputable is only a postulate that N. represents result of interaction between means for N. and c. the N of page, edge participates in this interaction at the level of neuron and interneural synoptic bonds.
Consideration of the main theories of N. shows that any of them is not capable to explain well all observed effects of the general anesthesia and, therefore, origins of N. Odnako of the bases finally to reject old theories is not present since the lipidic theory, e.g., correlates with idea of the minimum alveolar concentration of anesthetic better, than others.
Coagulative theory. In 1864 W. Kuhne, and in 1875 K. Bernard described the phenomenon of coagulation of protoplasm of cells under the influence of vapors of ether and chloroform. K. Bernard suggested then that reversible coagulation of protoplasm of nervous cells arising under the influence of anesthetics is responsible for N. Pytayas's development to explain physical. - the chemical mechanism H., K. Bernard connected his emergence with the change of surface intention, permeability of a cellular membrane, change of viscosity of protoplasm and other possible effects caused by ether and chloroform. However in the subsequent, in particular P. V. Makarov, (1938), it was shown that at the general anesthesia concentration of means for N. in a cell is so small that not only does not change colloidal state of its protoplasm, but has even no significant effect on intracellular carrying out excitement. The colloid theory was in essence refuted by it.
Lipidic theory. In 1866 Mr. Hermann suggested that N. can be result of physical interaction of anestetichesky means with intracellular lipids. The statement of this point of view was promoted substantially by establishment by G. Meyer and Overton (Ch. E. Overton) in 1899 and 1901 (independently from each other) the fact of direct correlation between expressiveness of narcotic effect of this means and its solubility in fats. The theory of distribution of means was developed for N. in fat and water on extent of its dissolution in these environments (a so-called distribution coefficient oil/water), according to a cut the narcotic force of substance is in direct dependence on the size of this coefficient. This dependence was convincingly confirmed for fat-soluble anesthetics by Idzher (E. I. Eger) with soavt, in 1965. However the patterns postulated by the lipidic theory are fair only for connections of one homologous series — acyclic hydrocarbons and inert gases and barbiturates, steroid anesthetics, etc. do not extend to other means for N., napr. In this regard the lipidic theory has no universal value.
Protein theory. In 1904 — 1905. Moscow criminal investigation department and Roaf (Moore, Roaf) established that nek-ry anestetichesky means (e.g., chloroform, ethylene, cyclopropane) form unstable chemical connections or physical units with cellular proteins. At the same time extent of communication of these connections depends on the partial pressure of drugs in solution and, therefore, defines direct dependence of depth of N. on concentration of anesthetic in an organism. However exact value of bonds of anestetichesky means with proteins in the mechanism of development of anesthesia remains not clear so far.
Theory of a boundary tension. A number of substances, first of all saturated hydrocarbons and alcohols, have ability to reduce surface intention of liquids, including and cellular environments, depending on force of the narcotic effect (Traube's theory, 1904, 1913). Further by Clements's works (J. A. Clements, 1962) it is established that inhalation anesthetics and nek-ry inert gases are capable сния^ать surface intention of lipoprotein membranes of air cells, and this effect is shown in direct dependence at most of narcotic effect of substance. The theory based on effect of change of surface intention and the change of permeability of cations connected with it through a cellular membrane has also no universal value as it became known that many inhalation anesthetics (e.g., galoidsoderzhashchy hydrocarbons) do not exert at all impact on surface intention while other surfactants (e.g., silicon compounds) have no narcotic effect.
The adsorptive theory it is based that a part of anestetichesky means is adsorbed on a surface of cellular membranes, and extent of oppression funkts, activities of a cell, including and nervous, is depending on number of molecules of means for N. adsorbed by a membrane [to S. Loewe, 1912]. D. N. Nasonov and V. Ya. Alexandrov (1940) offered the concept «the adsorptive blockade», meaning inability of any cell to connect any substances, i.e. to participate fully in metabolic processes, in the presence of anesthetic. The island Warburg (1914) assumed that the main effect of means for N. which is adsorbed on a surface of a cellular membrane is oppression of enzymatic activity of a cell. The theory has many exceptions and does not explain the processes happening in a cell during N.
Thermodynamic theory (or theory of inert gases). In 1939 Ferguson (J. To. W. Ferguson) formulated the provision that the narcotic force of inert gases and flying anesthetics is proportional to the partial pressure of their vapors. On this basis the conclusion that N. represents result of physical, but not chemical interaction between a nervous cell and anesthetic as at this interaction more important is the total effective volume of molecules of anesthetic, but not their number was made. This theory does not explain specific mechanisms of change funkts, activities of a cell in a condition of N.
Theory of water microcrystals. Attempts to open the mechanism H. were expressed also in studying physical. - chemical interactions between anesthetic and protoplasm of a cell. On the basis of the X-ray crystallographic analysis (see) it was established that atoms and molecules of a number of inert gases, and also ethane, cyclopropane, chloroform, etc. form in water solutions microcrystals in the form of various polyhedrons, in to-rykh the water molecules connected by hydrogen bindings appear, according to Klaussen (Claussen, 1951), L. Polinga (1961) grouped by molecules of various inert gases and anestetichesky means withheld in the center of these crystals by means of Van der Waals's forces. Also other pattern — dependence of this effect of temperature is clear. As at body temperature the possibility of formation of water microcrystals is practically excluded, L. The Poling indicated a role in this process of other chemical connections in particular bearing electric charge of side chains of proteinaceous molecules, to-rye in cases of interaction between anesthetic and a nervous cell at body temperature play a role of catalysts of this process, but at lower temperatures (25 °) can independently form water microcrystals in protoplasm of cells. In zones of synoptic communication microcrystals can interrupt process of carrying out excitement. Serious defect in the theory of water microcrystals was revealed by establishment of the following fact: many anestetichesky means (e.g., ether, Ftorotanum and metoksifluran) do not form water microcrystals at 0 °, the standard atmospheric pressure and their high partial pressure in mix at all (close to sizes of partial pressure of each of these anesthetics in the set conditions). Other objection against this theory was that many fluorinated anesthetics do not keep within the linear relation between their concentration and quantity of microcrystals existing for other anesthetics.
Theory of disturbance of oxidizing processes. M. Fervorn in 1912 assumed that effect of anesthetics is connected with the disturbance of oxidation-reduction processes in a cell bringing at rather high concentration of anesthetics in an organism to funkts, its insolvency. In experiences of in vitro of Brody, Beyn (T. M. of Brody, J. A. Bain, 1951) it is established that a number of the substances having anestetichesky activity reduces oxygen consumption by tissue of a brain without increase in concentration of intermediate products of exchange — a lactate, pyruvate, etc.; that barbiturates separate processes of oxidation and phosphorylation and reduce formation of ATP, but do not influence at the same time the general oxygen consumption by a brain. Products of ATP decrease under the influence of barbiturates first of all as a result of delay of oxidation rate in mitochondrions. At the same time it is established also that changes of cellular metabolism are not parallel to extent of oppression funkts, activities of separate cellular structures and, in particular, oppression of carrying out excitement through a sympathetic ganglion. It first of all concerns ether, cyclopropane and nitrous oxide, to-rye in the concentration blocking carrying out excitement on axons do not exert a little noticeable impact on oxygen consumption. It is known that practically all general anesthetics cause these or those disturbances of metabolic functions, however these disturbances are not parallel to expressiveness of narcotic effect and cannot explain completely me-* hanizm of emergence and maintenance of a narcotic state. Moreover, it became known that, nesmot * rya on the disturbances in separate nodes of a metabolic chain arising owing to effect of the general anesthetics nek-ry of them, napr, barbiturates and Ftorotanum, are capable to increase stability of c. N of page to a hypoxia and an anoxia.
Membrane theory. In the 70th interest in the idea of an explanation of mechanisms H. from the point of view of impact of the general anesthetics on properties of a cellular membrane revived. A thought that they affect a cellular membrane, changing it fiziol, permeability, was stated at the beginning of 20 century by Heber (Heber, 1907), Vinterstein (H. Winterstein, 1916). However after works of English scientists of A. Hodzhkin, E. Huxley who theoretically proved and experimentally confirmed the doctrine about physiology of a cellular membrane in 1949 — 1952 and conferred for these works the Nobel Prize in 1963 the membrane theory of N. receives a serious scientific basis. Under the influence of the general and local anesthetics and a number of other substances permeability of a cellular membrane for sodium, potassium and chlorine changes. It causes change of polarization of a cellular membrane and makes impossible generation of the action potentials having ability to independent distribution on a nervous cell and being the main substrate of specific function of a cell. In addition to the general and local anesthetics, reduction of permeability of a membrane, its stabilization and the subsequent reduction of action potential can be caused by the steroid substances which do not have specific hormonal activity, napr, viadril. There is also a point of view, according to a cut the general anesthetic causes long and permanent depolarization of a cellular membrane, the impossibility to generate action potential appears the investigation of what besides. However in both cases a starting point of effect of the considered substances is oppression of membrane permeability for ions under their influence. As almost all anestetichesky means behave in an organism, with biochemical, the points of view, rather inertly, i.e. do not enter actively chemical connections, there was an assumption that interaction of the general anesthetics with molecules of a cell membrane has not the chemical, but physical nature. Yet not all fiziol, the phenomena arising at effect of anestetichesky substances it is possible to explain from the point of view of the membrane theory. In spite of the fact that cumulative effect of all anesthetics as it is already proved, disturbance ionic membrane is permeability (see), the mechanism of oppression of functions of nervous cells is not identical to all anesthetics. It is possible to give as one of arguments of this situation different physical. - a chemical tropnost of various anesthetics to substances of the lipidic and protein nature. Researches of mechanisms H. within interaction of anestetichesky means with a cellular membrane, cellular organellas and other elements of a cell are only in an initial stage, in the USSR they are undertaken by T. M. Darbinyan and soavt. (1972).
Types of an anesthesia
the Inhalation anesthesia is carried out at inhalation of one or two (the mixed N.) gaseous or liquid flying anesthetics through a mask of the narcotic device or through an endotracheal tube (see. Inhalation anesthesia ).
Not the inhalation anesthesia is carried out by introduction to a vein of one or several solutions of anestetichesky and analgetic means (see. Not inhalation anesthesia ). Carry to not inhalation methods H. also ways when anesthetic is entered intramusculary (Ketaminum), rektalno (Narcolanum). The Pryamokishechny method H. is for the first time offered by N. I. Pirogov; most often it is used in pediatric practice.
The electroanaesthesia is carried out by means of the special devices generating weak currents of sinusoidal, rectangular or triangular shape, to-rye influence a brain of the patient through the electrodes imposed on the head (see. Electroanesthesia ).
In modern anesthesiology in most cases apply the combined types of anesthesia, aiming to reduce adverse effects of effect of each separate drug and to increase their positive properties (combined, or mixed, N.). Unlike the combined N., carried out by one any drug, call a monoanaesthesia.
About basis anesthesia speak in that case of a combination of drugs for N. when in the beginning not inhalation means, and then gaseous or flying anesthetic is used. In some cases simultaneous use of several means for N. in much reduced concentration provides adequate general anesthesia due to mutual strengthening of effect of drugs (the potentiated anesthesia).
Nitrous oxide (see) — inodorous colorless gas; weight of 1 l — 1,977 g.
It is stored in cylinders in liquid state under pressure of 50 am; 1 kg of liquid nitrous oxide forms at evaporation apprx. 500 l of gas; does not ignite. In an organism any connections does not join, well a rastvorim in water, intercellular lymphs and blood, not a rastvorima in lipids. It is chemically poorly active that allows to use alkaline absorbers of carbon dioxide during N. It is applied only in mix with oxygen to providing an analgesia at short-term out-patient and nontraumatic stationary operations, and also practically at all types of the combined N. Analgeziya comes at inhalation of mix, in a cut concentration of nitrous oxide makes 40 — 50 about. %, at concentration of nitrous oxide 60 — 80 about. the % is switched off consciousness.
In some cases gas-narcotic mix of oxygen and nitrous oxide is applied to carrying out an autoanalge-ziya, it is preferential in obstetric practice. During the developing of pains the woman in labor herself puts a mask on a face and breathes this mix before weakening of pain, independently regulating at the same time duration of inhalation.
Ethyl ether (see) — a transparent colorless liquid with the specific irritating smell and burning taste, well liposoluble and it is weak — in water, easily combustible and explosive, especially in mix with oxygen. It considerably limits its use. Ethyl ether — classical strong anesthetic with the expressed width of therapeutic action and powerful narcotic, analgetic and mioplegichesky effect. The analgesia comes during creation of concentration of ether in blood of 0,18 — 0,35 g/l, a surgical stage (III-1) — at 0,9 — 1,1 g/l that corresponds 3 — 6 about. % of vapors of ether in the inhaled mix.
Ftorotanum (see) — colorless transparent liquid with the unsharp sweetish smell reminding chloroform, well liposoluble and low solubility in water. For N.'s carrying out by Ftorotanum use special evaporators. Ftorotanum — the powerful anesthetic providing sufficient level H. already at 1 — 2 about. % of drug in respiratory mix. Introduction to N. (inhalation within 1 — 2 min. 2 — 3 about. %, sometimes to 4 about. %) bystry, quiet, without feeling of suffocation and other unpleasant feelings. Important advantage of Ftorotanum — it not - potential of explosion. However it possesses the expressed cardiodepressor effect that limits its use. Much less often in the combined anesthesia use metoksifluran (see), etran (enflurane), trichloroethylene (see), cyclopropane (see).
Barbiturates hexenal (see) and Thiopentalum-natrium (see) — powders, well water soluble. Apply intravenously in solutions 1 — 2% of concentration preferential to introduction N. and at the short-term operations which are not demanding a deep analgesia. 250 — 400 mg of each of drugs are caused by rather deep narcotic sleep proceeding 15 — 25 min. Thiopentalum-natrium has the expressed vagotonic effect in this connection danger laringo-and a bronkhiolospazma increases at its use.
Propanididum (see) — not barbituric anesthetic (it is entered in the list of drugs), derivative an eugenola, low solubility in water and representing the liquid dissolved in water with addition of cremophore. In a dose of 500 mg quickly causes N. lasting apprx. 4 — 5 min. which is followed by the short-term period of a hyperpnea. Use for short-term and diagnostic operations and various procedures, and also for introduction N.
Predion (see) — hormonal and inactive steroid drug in the form of crystal powder, well water soluble. Enter intravenously into 2,5 — 5% solution in number of 500 — 1000 mg. The anesthesia develops in 5 — 7 min. after introduction and 30 — 60 min. proceed. Drug is a little toxic, its therapeutic width is 3 times more, than at barbiturates. Irritant action on a vascular wall with possible subsequent development of phlebitis and vein thromboses significantly limits the sphere of its use.
Sodium hydroxybutyrate (see) — sodium salt gamma and hydroxy-butyric to - you are (GOMK) close on a structure and properties to piperidic to - those are to the biogenic substance which is contained in brain fabric is normal and taking part in regulation of nervous activity. In this regard GOMK, having at intravenous and internal administration narcotic and somnolent effect, consider as low-toxic. Represents powder, well water soluble in any proportions, solutions to-rogo have alkali reaction (pH to 8,7), and steady against sterilization by boiling. After introduction of GOMK in a dose 70 — 120 mgyg in 10 — 20 min. there comes the dream proceeding 2 — 4 hours. Depth of a dream gradually increases and reaches a maximum in 30 — 50 min. Drug strengthens action of other narcotic and analgetic means, but itself has almost no analgetic activity. Causes sufficient myorelaxation effect. Does not render significant effect on functions of breath and blood circulation. It is widely applied in anesteziol, practice as not inhalation anesthetic to introduction N. as means for carrying out the combined H.
In a modern anesteziol, practice for adequate N.'s providing use also a row pharmakol. means, to-rye do not treat directly drugs of group of means for N. Naiboley widely also sedatives, and also a number of the drugs carried in special group of means for N are applied antipsychotic, anxiolytic.
Droperidolum (see) — a neuroleptic from group of phenyl propyl ketones, the low-toxic drug used as one of fixed assets for carrying out neyroleptanalgeziya (see). Enter 15 — 20 mg intravenously. Drug has the expressed antishock effect, and also causes a moderate vazoplegiya. Duration of action apprx. the 2nd hour.
Fentanyl (see) enters the list of the substances carried to means for N. Primenyaetsya as a part of a neyroleptanalgeziya. Is the strongest analgetic surpassing morphine in analgetic activity honor by 100 times. During the carrying out a neyroleptanalgeziya enter 0,4 — 0,5 mg in the beginning, then fractionally intravenously on 0,1 — 0,2 mg in 10 — 15 min. Thalamonal which is mix of Droperidolum and fentanyl is applied to premedication in combination with atropine and diazepam.
Diazepam (see) treats group anksio lytic, sedatives. Possesses the expressed psychosedation. At intravenous administration even in usual doses causes the light sleep proceeding apprx. 25 — 40 min. Apply preferential as addition to a neyroleptanalgeziya, to premedication, and also at introduction N. for providing a so-called ataralgeziya (grech, ataraxia tranquility, indifference + algesis suffering, torture) — the method of the general anesthesia based on the combined use of tranquilizers (anxiolytic, sedative drugs) and modern analgetic means (fentanyl, pentazocine).
Introduction to a wedge, practice in 1942. muscle relaxants (see) allowed to improve sharply N.'s technique in connection with the appeared opportunity to manage selectively a muscle tone. Action of muscular relaxants (immobilization) is connected with blockade of transfer of nervous excitement at the level of a neuromuscular synapse in two ways: a) lengthening to physiologically inherent trailer plate of a phase of depolarization from several milliseconds up to 5 — 7 min. (the depolarizing relaxants); b) the prevention of emergence of a phase of depolarization of muscle fiber in connection with blockade of a postsynaptic membrane (not depolarizing relaxants).
In anesteziol, practice widely apply Muscle relaxants of both types of action. The depolarizing muscular relaxants (Dithylinum, suktsi-nilkholin, miorelaksin) use preferential for simplification of an intubation of a trachea at introduction N. and for maintenance muscle relaxation at short-term operations. Enter them intravenously in doses of 0,75 — 1,0 mg/kg each 5 — 7 min. Not depots-lyarpzuyushchiye muscular relaxants cause a relaxation from 20 to 90 min. therefore they are used at long operations.
In practice there are various schemes of introduction of muscle relaxants. Often before introduction of the depolarizing relaxants (suktsinilkholin), to an intubation of a trachea, carry out a prekurarpzation — introduction nedepolyarizuyushchpkh relaxants in small doses (d-tubocurarine — 5 mg, pavulon — 1 mg) for reduction of side effects at the subsequent introduction of a suktsinilkholin.
After N.'s carrying out with use of muscle relaxants the phenomena of a rekurarization, i.e. repeated oppression of a neuromuscular synapse after a complete recovery of its function by the end of operation are sometimes observed. Clinically it is shown by a repeated relaxation and respiratory depression. As prevention of this terrible complication serves control of adequacy of recovery of a muscle tone and independent breath, timely and optimum on a dose a dekura-rization (cancellation of muscle relaxants) by administration of antikholinesterazny drugs.
Components of an anesthesia
Narcotic dream — main constant component of modern anesthesia. At it consciousness of the patient is switched off that causes full amnesia. Switching off of consciousness at N. always precedes switching off of other types of sensitivity, including elimination of reactions to the nociceptive (destroying) irritations in the form of the painful answer, neurovegetative and other reactions, and also to relaxation of muscles. Therefore only with introduction to practice of methods of the combined anesthesia providing in addition to means for N., use of analgetics, muscle relaxants and other means need for deep N disappeared.
Analgesia — elimination of pain. It can be reached by superficial N.'s addition with derivatives of opium (morphine, Omnoponum), Promedolum, fentanyl, pentazocine. Many modern inhalation (Ftorotanum, etran), and also neingalyatsioiny (hexenal and thio-pental-sodium) anesthetics have almost no analgetic effect therefore it is necessary to supplement their action with analgetics. Other anesthetics (ether, metoksifluran, nitrous oxide) provide the sufficient analgetic effect which is not demanding addition. Switching off of consciousness in itself is capable to eliminate a psychoemotional component of perception of pain without participation of analgetic means; in this regard at good muscle relaxation carrying out operations using anesthetics with weak analgetic activity is possible (Ftorotanum, etran). The most powerful, though the short-term, analgetic effect can be provided with intravenous administration of fentanyl, to-ry widely apply to carrying out a neyroleptanalgeziya, combining it with a neuroleptic Droperidolum, a tranquilizer diazepam and muscle relaxants against the background of artificial ventilation of the lungs by mix of nitrous oxide with oxygen. The similar type of the combined anesthesia can be called both a neyroleptanalgeziya, and an anesthesia as it provides use of one of anestetichesky means — nitrous oxides.
Neurovegetative blockade at N. consists in stabilization of reactions of century of N of page in response to operation and it is reached by influence of anesthetics and analgetics, to-rye suppress extraordinary reaction, hl. obr. through influence at the level of the central regulating mechanisms of century of N of page. Blockade of peripheral effectors can be reached by use and cholinolytics (atropine, Methacinum, Scopolaminum), ganglioblokator (Pentaminum, a gigroniya, an arfonada) or according to special indications of alpha adrenoblockers (Tropaphenum, Regitinum).
Muscle relaxation is an obligatory component at extensive interventions, especially in abdominal surgery. At deep radio N. there comes the expressed muscle relaxation. Sufficient immobilization develops also at anesthesia etrany. At all other types of anesthesia, including superficial radio N., immobilization is reached introduction of muscle relaxants of the depolarizing and not depolarizing types of action. As Muscle relaxants in the corresponding doses switch off all any muscles, including respiratory, use provides them carrying out artificial ventilation of the lungs (see. Artificial respiration ).
Maintenance of adequate gas exchange (see. Gas exchange ) it is reached as at independent breath of the patient in the period of PI., and during the carrying out artificial ventilation of the lungs. For this purpose use a method of an assisted breast (at insufficient own), select the respiratory mixes containing optimum amount of oxygen and choose the mode of ventilation providing not only the maximum oxygenation of blood, but also optimum removal of carbon dioxide.
Maintenance of adequate blood circulation (see. Blood circulation ) it is aimed at providing an optimum system and organ blood-groove and transport of oxygen. During N. use the general methods of regulation of a hemodynamics by maintenance of sufficient volume of the circulating blood, compensations of blood loss transfusion of donor blood, plasma and various blood substitutes, carrying out managed hemodilutions (see). It is extremely important to keep stability of contractility of a myocardium and to support adequate cordial emission. One of effective receptions is regulation of the general peripheric resistance by means of vazopres-sor or vazodilatator. An important element of maintenance of adequate blood circulation is ensuring sufficient venous return, to-ry in some cases (during the performance of large operations and at patients in a serious condition) control in size of the central venous pressure. The adequate diuresis during N. (not lower than 50 ml/hour) reflects satisfactory volume renal and, therefore, the general blood-groove.
Regulation of metabolism is one of the most difficult components of an anesthesia. In most cases it is reached by regulation of already described components (adequacy of gas exchange of N of blood circulation) and provided with timely compensation of shifts of acid-base and electrolytic balance. For providing a normal course of protein and energy balance the organism has the sufficient reserves which are completely satisfying metabolic functions during operation and N. Outside the narcotic and operational period there is a need in addition to enter solutions of carbohydrates and proteinaceous drugs into an organism (preferential amino acids). Important element of regulation of metabolism is the prevention of heat waste by an organism in the period of N. and after it. This problem is solved to a certain extent by active warming of the patient after N. on the operating table. In some cases for decrease in intensity of exchange processes during operation the method of a moderate hypothermia is used, at a cut body temperature artificially reduce by external cooling in the conditions of N. and full muscle relaxation providing switching off of thermoregulatory activity of an organism and a possibility of effective cooling (see. Hypothermia artificial ).
At separate operations quite often there is a need of providing special conditions N. Tak, e.g., at lung operations one-pulmonary N. and blockade of one of bronchial tubes are sometimes necessary; in neurosurgical practice quite often it is required to carry out preliminary dehydration of a brain by means of osmodiuretik (urea, a mannitol) or to bring cerebrospinal liquid out of cerebral cavities; at patients with diseases of the carrying-out system of heart in the period of N. cardiostimulation sometimes is necessary.
Indications to an anesthesia
At the choice between local anesthesia and N. it is necessary to be guided by the principle: the serious condition of the patient, the is more than indications for carrying out P. allowing to support fullestly a homeostasis due to providing a narcotic dream, an analgesia, neurovegetative blockade and a giiorefleksiya, a miorelaksa-tspa and a possibility of management of functions of blood circulation and breath. So, if frustration of a hemodynamics were result of disturbance of sokratitelny function of heart (myocardial infarction), the best way of anesthesia at transactions of vital indications is N., but not local anesthesia as only N. in the conditions of artificial ventilation of the lungs provides a possibility of management of functions of an organism. At traumatic shock of N. it is shown both as means of anesthesia and as a way of stabilization of a number of other functions — a hemodynamics, metabolism and breath.
At patients in a serious condition correctly chosen and carried out N. usually leads to improvement of a state and, therefore, creates favorable conditions for carrying out operation. At small on volume, the low-traumatic operations which are not demanding management of functions of an organism preference of local or peridural anesthesia can be given.
Technique of an anesthesia
Preparation for an anesthesia. Distinguish the general preparation for N. and special pharmakol, preparation — premedication. The general preparation includes preliminary sanitation of an oral cavity, bowel emptying and a stomach (if in it there are contents), normalization of water and electrolytic balance, elimination of deficit of components of volume of blood and normalization of blood circulation.
The condition of the patient before N. is estimated on the following indicators: arterial and central venous pressure, frequency and the nature of breath, an ECG, volume of the circulating blood, composition of blood and urine, biochemical, composition of blood, content of electrolytes in blood and urine, acid-base equilibrium and gas composition of blood, etc. At the expressed disturbances of a hemodynamics hold the events directed to their elimination. Hypovolemia) eliminate with hemotransfusion or infusion of middlemolecular dextrans (Polyglucinum) or colloid solutions. At dehydration the patient repeatedly enter salt solutions and isotonic solutions of glucose, at a metabolic alkalosis within several days before N. and operation — solutions of potassium chloride and glucose with insulin. Administration of sodium in an organism in any kind at a metabolic alkalosis is contraindicated.
Premedication has a main goal removal of psychoemotional tension before operation, simplification of introduction to N., maintenance of stability of N. and easier escaping it. Sufficient Premedication eliminates concern of the patient, removes internal stress it, causing drowsiness, and suppresses secretion of bronchial contents and saliva. Important purpose of premedication is the prevention patol, reflexes, hl. obr. cardiac arrhythmias, to-rye can arise during N. in connection with immediate effect of flying anesthetics and muscle relaxants, and also to be a consequence of afferent influences from upper respiratory tracts and visceral bodies, on to-rykh operation is made at present. The narcotic analgetik used for premedication, in addition to the main analytical effect, reduce a tachypnea, caused, e.g., by trichloroethylene, and also suppress the possible physical activity of the patient resulting from excitement of the extrapyramidal system connected using barbiturates, napr, thiofoams-tala-sodium. Inclusion in structure of means for premedication of fenotiazi-new drugs (aminazine) reduces the level of heat production of an organism.
For premedication use: a) sedatives — barbiturates (phenobarbital, amytal of sodium, etc.), fenotiazinovy drugs (aminazine, isopromethazine); even more often apply diazepam (Seduxenum), to-ry not only gives good tranquilizing effect, but also has the big width of therapeutic action and in this regard it is rather safe; b) narcotic analgetik — morphine, synthetic drugs Promedolum and fentanyl; c) antipsychotic drugs — degidro-benzperidol (Droperidolum); d) para-sympatholytics — atropine and Scopolaminum.
Simple options of premedication are most widespread: 1) amytal-sodium of 0,2 g for the night, Promedolum of 10 — 20 mg and atropine of 0,7 mg intramusculary in 40 — 50 min. prior to the beginning of N.; 2) for night of 10 — 15 mg of diazepam inside, in 1 hour prior to the beginning of anesthesia of 5 — 10 mg of solution of diazepam intramusculary and in 30 min. 1,5 — 2 ml of thalamonal and 0,5 — 0,7 mg of atropine intramusculary. After premedication to the patient do not allow to get up and deliver to the operating room on a wheelchair.
Introduction anesthesia (induction of anesthesia) — a way of the beginning of anesthesia, at Krom provide bystry, safe and effective switching off of consciousness, loss of painful sensitivity and muscle relaxation without stage of excitement of the patient and the necessary depth of anesthesia allowing to carry out transition to maintenance of anesthesia on the fixed set level. During mask radio and chloroformic N.'s development widely applied a method of a so-called raush narcosis, at Krom to the patient allowed to inhale quickly anesthetic in high concentration, to-ry poured idle time on a gauze anesthetic inhalers (see). From modern positions this method is considered as «a hypoxemic suffocation», extremely dangerous, anti-physiologic; is of only historical interest.
Introduction N. is begun in the operating room or the special preoperative room after the corresponding preparation of the narcotic equipment and a narcotic little table (fig. 1). Prior to broad use of a classical method of introduction anesthesia with use of solutions of barbiturates, neyroleptanalgetik, Propanididum, etc. in combination with muscle relaxants long time applied introduction N., gradually entering the patient inhalation Anesthetic Ether, cyclopropane, chloroform, Ftorotanum through a mask of the narcotic device to the level providing not only a loss of consciousness and switching off of painful sensitivity, but also the muscle relaxation allowing to carry out an intubation of a trachea (see. Intubation ). Such method of induction finds application in pediatric anesthesiology as it is technically simpler at the child and is easier transferred by it, than intravenous introduction N. U adults introduction N. in most cases is provided with an intravenous injection by 1 — 2% of solution of barbiturates of short action (Thiopentalum-natrium, hexenal), neyroleggtanalgeti-k (thalamonal, or separate administration of fentanyl and a degidrobenzperidol) in combination with diazepam or other tranquilizers, and also intravenous administration of a tgropa-nidid. Muscle relaxation is reached by intravenous administration of suktspnil-sincaline or a pavulon (pankuronium-bromide). During the short period from the moment of a loss of consciousness to development of a full muscular relaxation carry out artificial ventilation of the lungs by means of the narcotic device through a mask mix of 50% of oxygen and 50% of nitrous oxide. Introduction N. and all further period of N. document in the special narcotic card where reflect dynamics of heart rate, the ABP and other this overseeing by a condition of the patient and the main actions for N.'s maintaining in various stages. Introduction N. — the most dangerous period of anesthesia as at this particular time there is a bystry transition of an organism from one fiziol, a state in another at yet not died away vivacity of reflex answers. The main complications — a metastasis ad nervos of a hemodynamics and a heart rhythm, disturbance of passability of respiratory tracts (bronkhiolospazm, a laryngospasm), vomiting and regurgitation. An important role in development of hypotension (see. Hypotension arterial ) in the period of introduction N. by means of barbiturates plays a cardio-depressor effect of the last. In this regard it is reasonable to enter barbiturates in the concentration which are not exceeding 1 — 2%. Even at the favorable course of induction of anesthesia after an intubation of a trachea the incontinuous period of hypertensia is quite often observed (see. arterial hypertension ), the origin a cut can possibly be connected with the reflex resulting from irritation of a trachea an endotracheal tube. Local anesthesia of a mucous membrane of a trachea at the time of an intubation considerably reduces reflex irritability it, but does not eliminate completely. More rare is the reason of hypertensia hypoxia (see) and hypercapnia (see) in the period of introduction N. developing in connection with the inadequate ventilation of the lungs preceding an intubation of a trachea. The most frequent reason of the bronkhiolospazm developing at introduction N. (see. Bronchospasm ) — insufficient depth of anesthesia. As the contributing factors to development of a bronkhiolospazm serve insufficient blockade of a parasympathetic part of century of N of page, use of sulfur-containing barbiturates, cyclopropane, and also irritation of respiratory tracts an endotracheal tube in the conditions of insufficiently deep anesthesia. Bronkhiolospazm is shown by the falloff of a pliability of lungs, small respiratory volume, the convulsive movements of all body complicated by a breath and an exhalation, rattles. To elimination it is applied by inhalations of Ftorotanum in small concentration, sometimes Trilenum or ether, intravenously enter novocaine, an Euphyllinum, succinyl-sincaline, Promedolum. The satisfactory result is yielded also by introduction of Isadrinum. Ventilation of the lungs in the period of a bronkhiolospazm is carried out manually a bag of the narcotic device, at the same time insufflirut 100% oxygen. The method of massage of lungs for treatment of a bronkhiolospazm wide did not find a wedge, applications. Vomiting (see) and hl. obr. regurgitation of gastric contents (see. Reflux ) can arise in any period of N., however most often it happens during induction. This complication becomes especially dangerous if it remains unnoticed. Acid contents of a stomach, pH to-rogo happen lower than 2,5, getting into a trachea, bronchial tubes and bronchioles, causes a chemical burn of a mucous membrane of respiratory tracts with the subsequent development of so-called aspiration) a pneumonitis, an exudative and purulent tracheobronchitis, diffuse or focal pneumonia. This complex of the phenomena is known under the name «Mendelssohn's syndrome». The main measure of prevention of vomiting and regurgitation in the period of N. is gastric emptying before N., position of the patient with the raised head (Fowler's position), overlapping of a gleam of a gullet with pressing on a cricoid of a throat during the entire period of introduction N. and an intubation of a trachea (reception the Sell and). One of measures of prevention of regurgitation and flowing of contents of a stomach in a trachea is sounding of a stomach (see) for N., failure from use of bezmanzhetochny endotracheal tubes and total failure from a method of a tamponade of a pharyngeal cavity. If aspiration of gastric contents nevertheless happened irrespective of, the patient had a vomiting or regurgitation, carry out the following to lay down. actions: 1) immediately intubate a trachea of the patient (if the intubation is not made earlier); 2) suck away contents from a trachea and bronchial tubes; 3) in intervals between the periods of suction carry out artificial ventilation of the lungs for complete elimination of a hypoxia; 4) through an endotracheal tube repeatedly wash out a trachea and bronchial tubes of 4% solution of bicarbonate, to-ry enter 15 — 20 ml and immediately suck away (lavage of lungs); 5) after each lavage, and also at the end of N. before extubation enter 100 — 200 mg of a hydrocortisone in solution into a trachea and bronchial tubes; in the postoperative period within several days appoint a hydrocortisone intramusculary; b) intravenously enter an Euphyllinum for the prevention and treatment of a spasm of bronchial tubes; 7) after extubation (or in the presence of an endotracheal tube in a trachea) make rentgenol, control of a thorax for identification of an atelekta-zirovaniye of lungs; 8) if there is a suspicion on existence in bronchial tubes of food masses and any other conglomerates, to-rye it is impossible to remove with simple suction, make a bronkhoskopiya (better the injection bronchoscope), at a cut carry out all complex of the above described actions.
In induction period of anesthesia, both at inhalation, and at an intravenous method, cough is possible (especially often at smokers). Its emergence can be connected with irritation of a throat at inhalation of anesthetic (especially ether) in high concentration, and also with the irritating impact on a throat of gastric contents or saliva. Prevention is gradual increase in concentration of inhalation anesthetic, and also elimination of flowing of liquid contents in a throat. Cough can also be interrupted with bystry immobilization of the patient with introduction of muscle relaxants.
Period of maintenance of an anesthesia on time matches duration of operation. At short-term interventions use anesthetics and Muscle relaxants with the short period of action (Propanididum, barbiturates, nitrous oxide, Ftorotanum, with-uktsinilkholin), at long operations frakdi-onno administer the drugs for a neyroleptanalgeziya, Ftorotanum or ether in a combination with nitrous oxide, hydroxybutyrate of sodium, tubokurariya or pavulon. A main objective of N. during maintenance is protection of the patient against an operational injury and providing the best working conditions of the surgeon. For this purpose the anesthesiologist shall control continuously depth of anesthesia, its adequacy to character and a stage of intervention, to support optimum gas exchange, to estimate and compensate a loss of blood, to prevent undesirable neurovegetative reactions, to korrigirovat hemodynamic SHIFTS.
Removal from an anesthesia begins with the termination of introduction to an organism of anestetichesky means. Though return of consciousness also matches recovery of compensatory and adaptable mechanisms, escaping of N. on it does not come to an end. Even at recovery of consciousness at the patient within several minutes and even hours (depending on a look and N.'s duration) there is an oppression of respiratory function, an adynamia and muscular weakness.
At the same time during this period the central thermoregulatory mechanisms are recovered, at the patient the fever, to-ry, from the point of view of compensation of functions begins, promotes recovery of a normal temperature homeostasis. Due to activation of functions of the patient needs the increased amount of oxygen, a cut it can be provided only in the conditions of the recovered breath.
N.'s duration is defined by specifics of operation, depth of anesthesia and time of removal of anesthetic from an organism. At radio and metoksifluranovy N. process of escaping of N. is begun earlier, than at ftorotanovy. At a neyroleptanalgeziya fentanyl stops being entered in 20 — 30 min. prior to the end of operation. Favorable and fast escaping of N. in many respects depends on art of the anesthesiologist. It is necessary that on the operating table at the patient elements of consciousness were recovered (ability to answer the elementary questions and to carry out elementary instructions), breath, adequate on volume, and the main protective reflexes (tussive and pharyngeal). Criterion of adequacy of breath is the respiratory volume not lower than 400 — 500 ml, and also the satisfactory pO level 2 , pCO 2 and pH of blood. The main reasons for the slowed-down recovery of adequate spontaneous breath: 1) carrying out artificial ventilation of the lungs in the period of N. in the mode of a hyperventilation, at Krom the C0.2 level in blood decreases and by N.'s end does not reach the threshold necessary for normal excitement of a respiratory center; 2) shift of acid-base equilibrium of blood towards the acidosis which is slowing down hydrolysis of the depolarizing relaxants and oppressing secretory function of kidneys; 3) suppression of neuromuscular conductivity the anesthetic which was not in time to leave an organism yet; 4) deepening of neuromuscular blockade after introduction to time of operation of antibiotics; 5) overdose or excess accumulation in an organism of muscle relaxants.
After use of not depolarizing muscle relaxants carry out a dekurarization. Its sense is that at administration of antikholinesterazny drugs (prozerin) favorable conditions for accumulation in a zone of a myoneural synapse of a mediator of acetylcholine providing direct transfer of an impulse from a nerve on a muscle are created. Dekurarization will be seen off only in that case when the patient had elements of spontaneous breath. Usually slowly enter 0,04 — 0,05 mg/kg of a prozerin intravenously (sometimes fractionally) after preliminary administration of atropine for removal of parasympathomimetic effect, the prevention of bradycardia and an asystolia. In nek-ry cases awakening of the patient is forced (and control adequacy of his breath) intravenous administration of 2 — 3 ml of solution of Cordiaminum or water-soluble camphor. These drugs are first of all powerful respiratory analeptpka though their this effect and is not really long. After a neyroleptanalgeziya as a respiratory analeptic quite often apply fortrat (pentazocine), using at the same time, in addition to analgesic effect, its antagonistic in relation to fentanyl at action. For the same purposes use nalorfpn — drug with the expressed antagonistic effect in relation to morphine and morfinopodobny drugs.
Extubation of a trachea is made only after recovery of consciousness, reflexes and initial volume of lung ventilation. Before extubation suck away contents from a trachea and an oral cavity.
The main signs of full awakening after N., the terminations of curarization and recovery of spontaneous breath the following: the patient talks, at a request freely moves extremities, can tear off a nape from a head restraint; it is capable to clear the throat; can make several deep breaths on. to instructions of the anesthesiologist; the patient has no cyanosis; the movements of a diaphragm and a costal framework of a thorax are synchronous (there is no paradoxical breath); minute volume of lung ventilation of not less initial.
In the presence of all these signs of the patient it can be transferred to postoperative chamber of intensive observation. Before transfer the anesthesiologist is obliged to estimate once again blood loss and efficiency of blood substitution, to listen to cardiac sounds, to measure the ABP and to estimate peripheric circulation, a diuresis and to be convinced that the oral cavity is free from contents. The chamber of intensive observation surely does a x-ray film of lungs for identification of possible atelectases and other complications.
The clinical picture of an anesthesia
N. any anestetichesky means develops on certain patterns (staging), specific to each anesthetic or their combination. Due to the introduction to broad practice of the muscle relaxants which provided a possibility of carrying out anesthesia at superficial stages and also in connection with use during N. not of one, but several anesthetics with multidirectional type of action supplementing each other, the classical concept «clinic of an anaesthesia» lost the former value. It, in turn, complicated a possibility of assessment of depth of anesthesia and its adequacy, raised requirements to qualification of the anesthesiologist and led to creation of new objective methods of assessment of anesthesia (an electroencephalography, a miografiya). The clinical picture and staging of development of N. can be fullestly tracked on the example of radio by N. Sushchestvuyet A. E. Guedel's classification providing four stages of radio N.:
III \surgical stage (tolerant);
W. W. Mushin allocates in a surgical stage of N. three levels (superficial, average and deep), and I. S. Zhorov instead of an agonal stage suggests to allocate a stage of awakening. The I stage (analgesia) comes in 3 — 8 min. inhalation of ether at its concentration in blood of 0,18 — 0,35 g/l. The patient loses orientation in a surrounding situation, becomes talkative, then gradually falls into a drowsy state, from to-rogo it it is possible to remove easily the loud address. At the end of the I stage consciousness is switched off and there comes the analgesia. The II stage (excitement) is characterized by activation of all fiziol, processes and manifestations — the patient is excited, breath noisy, pulse becomes frequent, the ABP raises, all types of reflex activity amplify. In the III (surgical) stage excitement stops and functions are stabilized fiziol. Range of a surgical stage is big — from superficial N. with preservation of the majority of reflexes to deep when activity of the respiratory and vasomotor central regulating mechanisms is suppressed. In a stage of III 1 (superficial, the first, the level of a surgical stage) there comes the quiet equal dream with preservation of lid and pharyngeal and guttural reflexes and a muscle tone. In this stage it is possible to execute only short-term and low-traumatic operation. Operations on bodies of belly, chest cavities and nek-ry others are possible only at introduction of muscle relaxants. In a stage of III2 (the average level of a surgical stage) at disappearance of reflex activity and a muscle tone against the background of a satisfactory hemodynamics and breath there is possible a performance of operations on abdominal organs without use of muscle relaxants. In a stage of III3 (deep level) toxic impact of ether on an organism begins to be shown, at Krom there occurs gradual expansion of pupils, their reaction to light dies away, rhythm and depth of breath is broken, tachycardia accrues, the ABP decreases, the full muscular atony develops. N.'s deepening to a stage of Sh3 (at a monoanaesthesia) is admissible only on a short time term at somatic healthy subjects at an obligatory assisted breast. The stage of III4 (allocated with Gedel) is characterized by limit oppression fiziol, functions with paralysis of intercostal muscles, suppression of contractility of a diaphragm, hypotonia, paralysis of sphincters. More or less long maintenance of N. at this level is impossible as soon it passes into an agonal stage with deep disorder of breath, disappearance of pulse and the subsequent termination of blood circulation. About a wedge, positions H. in a stage of III3 during the long period it is inadmissible. The N in a stage of III4 is inadmissible under no circumstances. The stage of awakening beginning at complete cessation of intake of anesthetics in an organism is characterized by almost consecutive passing of all stages of N. upside-down, but in a little reduced look (there is almost no excitement, e.g.), to a complete recovery of consciousness.
Inhalation monoanaesthesia nitrous oxide carry out at breath of the patient with mix of nitrous oxide with oxygen in the ratio 4: 1 at the general gas-current of 8 — 10 l/min. In 5 — 6 min. after the beginning of inhalation of such mix there comes the loss of consciousness about a nek-eye motive and speech excitement, sometimes laughter (it gave the grounds to call nitrous oxide laughing gas). In 2 — 3 min. there comes N. in a stage of III1. It is not possible to receive deeper level of anesthesia, as a rule. Increase in concentration of nitrous oxide in respiratory mix is inadmissible since involves a hypoxia. Level of the reached analgesia satisfactory, but a sufficient muscular relaxation does not develop therefore in the conditions of a monoanaesthesia nitrous oxide performance only of small operations which are not demanding muscle relaxation is possible. In modern anesthesiology nitrous oxide is widely used as obligatory anesthetic of any combined N. Thanks to beta adrenomimeticheskomu to effect it not only influences cordial activity, but also levels to a certain extent a negative inotropic effect of nek-ry anesthetics, napr, Ftorotanum.
Nitrous oxide in combination with oxygen is widely used during the carrying out to lay down. an anesthesia, to-ry it was developed by B. V. Petrovsky and S. Efuni as a method of postoperative anesthesia. To the patient in the postoperative period carry out by means of a mask or nasal catheters of inhalation of gas-narcotic mix of nitrous oxide with oxygen in ratios of O 2 : N 2 O — 1: 1, 1: 2, 1: 3.
Current ftorotanovy monoanaesthesia subdivide into three stages: I \initial, II — transitional (similar to a stage of excitement at etherization) and III — surgical. The initial stage developing at inhalation 1,5 — 2 — 3 about. % of Ftorotanum in respiratory mix, it is short (1,5 — 3 min.) also comes to an end at quet breathing and stable blood circulation with loss of consciousness. The transition phase at ftorotanovy N. is observed very seldom and if arises, then no more than 1 min. proceed and shown by easy excitement and sluggish attempts of the patient to rise from a table. In a surgical stage, at a cut performance of operative measures is possible, allocate two or three levels. Already the satisfactory muscular relaxation against the background of initial signs of decrease in reflex activity and nek-ry decrease in the ABP and slight bradycardia develops in stages of III1 of ftorotanovy anesthesia at patients. It is established that the hypotensive effect which is traced on all stages of ftorotanovy N. is caused first of all by a cardiodepressor effect of anesthetic and connected with this decrease in cordial emission. The stage of III2 is characterized by further fading of reflex activity, considerable muscle relaxation, hypotonia and bradycardia; increase of a respiratory rhythm during the easing costal and strengthening of diaphragmal respiration can be observed a nek-swarm. In this stage comes full muscle relaxation, essential respiratory depression, both costal, and phrenic; skin remains dry and warm to the touch, skin color and nail beds usual pink and only at essential respiratory depression develops a Crocq's disease, and sometimes and the general cyanosis. The expressed hypotonia, bradycardia develops in stages of III3, pupils begin to extend. At all stages of N. Ftorotanum observes the progressing decrease in cordial emission of cardiodepressor genesis, a cut only in insignificant degree is compensated by increase in the general peripheric resistance or is not compensated at all, as explains arterial hypotension. However in deep stages of ftorotanovy N. the general peripheric resistance is always increased, and it causes satisfactory effect of so-called centralization of blood circulation, at a cut satisfactory perfusion of vitals (a brain, a liver, heart and kidneys), and also skin (pink and warm skin) even remains at the low volumes of cordial emission. As ftorotanovy hypotension has kardio depressor character, use of the increased concentration of Ftorotanum for receiving the so-called managed hypotonia with Kliniko-fiziol, positions cannot be justified.
Etranovy N. (at inhalation of anesthetic in number of 2 — 3 about. the % in the inhaled mix) is characterized by bystry approach of a narcotic dream without the period of excitement and the hl is followed by the moderate arterial hypotension caused from the very beginning N. (unlike N. Ftorotanum). obr. a vazoilegiya at very moderate kardpodepres-these, coming only in the period of deep N. Accurate staging in a wedge, etranovy N.'s current usually is absent as extremely bystry change a wedge, signs is observed. In the whole N. etrany proceeds at good stability of hemodynamic indicators without symptoms of a depression of function of breath and at the satisfactory muscular relaxation allowing to perform small operations without use of muscle relaxants. However the insufficient analytical properties of an etran (which were even less expressed, than at N. by Ftorotanum) cause the necessity of addition H. one of analgetics.
To reflect the narcotic force of this or that inhalation anesthetic and to express it through an indicator of percentage of anesthetic in the inhaled mix, i.e. to find equipotentiality of anesthetics, the concept about the minimum alveolar concentration is entered. Concentration of inhalation anesthetic in respiratory mix is taken for minimum, at a cut in 50% of cases the painful reflex answer to a section of skin is suppressed. At a research of this indicator at people its following values for various anesthetics are established: diethyl ether — 1,92 about. %, Ftorotanum — 0,765 about. %, metoksifluran — 0,16 about. %, etran — 1,6 about. %, cyclopropane — 9,2 about. %, nitrous oxide — 101 about. % (i.e. 100% of concentration of nitrous oxide in most cases appear insufficiently for the prevention of the reflex painful answer to a section of skin).
The wedge, the picture H. caused by specific inhalation drug — ether, Ftorotanum, etrany, etc., has as it is stated above, the specific features. To each stage and level H. there corresponds a certain concentration of anesthetic in blood. During the use as the main anesthetic of ether I the stage (analgesia) develops at achievement in a venous blood of concentration of ether of 18 — 35 mg in 100 ml; The II stage of radio N. (excitement) is reached at increase in content of ether in a venous blood to 40 — 90 mg in 100 ml; The III stage of radio N. is characterized by the content in blue blood of ether in concentration from 90 — 110 to 140 — 180 mg in 100 ml.
The I stage of ftorotanovy N. develops at achievement of concentration of drug in a venous blood of 8 — 9 mg in 100 ml. Superficial level III of a stage of ftorotanovy N. is characterized by concentration of Ftorotanum in a venous blood of 9 — 11 mg in 100 ml. The average level — 12 — 17 mg in 100 ml. Deep level of ftorotanovy N (III) develops at concentration of Ftorotanum in a venous blood of 21 — 31 mg in 100 ml.
Creation of necessary concentration of anesthetics in an organism and to maintenance of appropriate levels of N. is promoted by use of narcotic devices and exact evaporators for inhalation drugs. In fig. 2 the device for carrying out an anesthesia of «Nar-kon-P» is presented, to-ry allows to use as anesthetic ether, Ftorotanum and nitrous oxide as separately, and in various combinations with each other, and as carrier gas — pure oxygen or the oxygen air mixture containing 45 about. % of O 2 , and also usual air.
In fig. 3 more perfect model of the narcotic device — «Polynarcon» is presented, edges it is counted on use of ether, Ftorotanum, trichloroethylene, cyclopropane and nitrous oxide. «Poly-наркон-2» it is intended for inhalation N.'s carrying out by various means; it, as well as Narkon-P and «Polynarcon», provides high precision and stability of maintenance of necessary concentration of vapors of anesthetic (at the expense of the evaporator) over a wide range of change of a consumption of carrier gas (fig. 4). Use of devices for inhalation N.'s carrying out with exact evaporators creates the best conditions for carrying out N.
N.'s clinic neingalyatsponny drugs (barbiturates of short and ultrashort action — Thiopentalum-natrium, hexenal, bay-tinaly, kemitaly) it is characterized by bystry development of a narcotic dream, almost total absence of excitement, weak analgetic effect and an insufficient muscular relaxation. It is accepted to divide a current of the barbituric N. reached by intravenous slow administration of 1 — 2% of solution (to 500 — 700 mg of drug), into three stages. The stage of I is reached already at introduction of 150 — 200 mg of drug and characterized by bystry quiet backfilling of the patient about a nek-eye with respiratory depression, increase in guttural and gag reflexes at stability of a hemodynamics. In a stage of II expansion of pupils, preservation of the reflex activity which is completely excluding a possibility of an intubation of a trachea without relaxants and a respiratory arrhythmia sometimes till the short-term periods of an apnoea is observed a nek-swarm. Motor reaction on pain stimulation is possible. In a stage of the III (surgical) reaction to pain completely disappears, there comes the moderate muscular relaxation, breath becomes superficial. In this stage the oppression of sokratitelny function of a myocardium which is shown the progressing hypotension develops, can pass edges at further deepening of N. into an apnoea and an asystolia. The cardiodepressor effect and threat of an apnoea at barbituric N. are not so much connected with the general dose of anesthetic entered throughout a considerable time term, how many by its high concentration (5% or 10%) and very bystry introduction. In this regard use of barbiturates in the concentration exceeding 2%, inadmissibly. In most cases barbiturates use only for introduction N.
Adequacy of an anesthesia (control methods)
the General assessment of adequacy of an anesthesia, i.e. its compliance to character, injury and duration of operation, is under construction on the basis of assessment of separate components on indicators of the general condition of the patient, reflex activity, a hemodynamics, gas exchange and transport of oxygen, function of kidneys, muscle relaxation, electric activity of a brain, etc. N.'s complexity complicates determination of depth of a narcotic dream in the usual standard parameters. At the same time the tendency to use of preferential superficial levels of anesthesia considerably increasing safety and N.'s efficiency levels need of exact assessment of level and depth of anesthesia. In modern conditions for assessment of adequacy of N. use a number of all-clinical indicators (such as heart rate, the ABP, color of a skin iokrov, a condition of a tone of cross-striped muscles, etc., supplementing them with special researches (an electroencephalography, an electromyography, definition of gas composition of blood, volume of the circulating blood, cordial emission, etc.), need in to-rykh arises in special situations.
Frequency of cordial it is reduced and y. After premedication, the cut almost always is a part of means atropine, moderate tachycardia (apprx. 90 — 100 ud/m in) is a usual state. Bradycardia against the background of m - cholinolytic blockade by atropine, especially in combination with arterial hypotension, demonstrates the essential deepening of N. adjoining on overdose of anesthetic. At ftorotanovy anesthesia moderate bradycardia is usual; it develops from the very beginning of N., but becomes expressed (to 50 — 40 beats/min) if N. deepen excessively. Such bradycardia represents predictively an adverse sign. The accruing tachycardia, especially, if it is combined with hypertensia, is characteristic of an insufficient analgesia even in the conditions of satisfactory reflex blockade and miorelaksatsip.
Arterial pressure is an integral indicator and is in direct dependence on cordial emission and the general peripheric resistance. Thus, this indicator only indirectly reflects a system blood stream, but is valuable in combination with assessment of other parameters of a hemodynamics (e.g., the central venous pressure, pulse, an ECG). For introduction N., especially for the period of an intubation of a trachea and during the near future after it, moderate hypertensia as reflection of yet not suppressed reflex activity is characteristic.
Of the majority of types of N. (with its average depth meeting surgical requirements and good miorelaksatsip) it is characteristic normal the ABP. The hypertensia developing during N. (at confidence in lack of a hypercapnia), practically always testifies to insufficiency of analytical effect of the general anesthesia and demands either N.'s deepening, or addition of its analgetikama. Hypotension during N. (if it is not caused in the artificial way by means of ganglioblokator) is undesirable and almost always (in the absence of a hypovolemia) reflects too deep level N. In most cases hypotension happens caused by decrease under the influence of anesthetic of sokratitelny properties of a myocardium and reduction of cordial emission, it is more rare happens the investigation of a secondary narcotic vazodilatation.
Monitor observation with periodic record ECG on a tape is an important control method of adequacy of anesthesia and all course of N. Vstrechayutsya various undesirable forms of changes of an ECG — from elementary constants (in shape takhi-or bradycardia) or periodic disturbances of a rhythm (in the form of various ekstrasistoliya) before difficult disturbances of conductivity, the general ischemia and hypoxia of a myocardium or local disturbances of coronary circulation. Periodic arrhythmias are predictively not dangerous and disappear in most cases with change of a general regime of N. and its separate components. Changes of food of a myocardium are more characteristic of elderly patients, have more serious basis and are connected with the mode H. only indirectly, i.e. can develop at any levels of anesthesia.
Definition of cordial emission — a difficult method of assessment of anesthesia; it is carried out only according to indications. Apply the thermodilution method providing preliminary catheterization of a pulmonary artery the special floating probe of Svan — the Ghanaian and cultivation of dye by method X amyl of tone.
Assessment of spontaneous ventilation of the lungs is based on the accounting of frequency and depth of breath, its character (the costal, phrenic or mixed type), the minute volume of breath (MVB) determined with the help gas meter (see) — a ventilometra. Consider also a wedge, symptoms — emergence of cyanosis, perspiration, tachycardia, hypertensia etc. Key parameter in assessment of breath is FASHION, to-ry later definition by means of veins-tilometra it has to be compared with the due sizes FASHION found according to Radford's nomogram. At oppression of spontaneous breath and decrease in FASHION carrying out an assisted breast or artificial ventilation of the lungs is shown.
Assessment of artificial ventilation of the lungs is made on the basis of theoretically found for this patient on the nomogram Radford due FASHION on indicators of a ventilometr — the device defining amount of expired air. Use also an indicator of pCO 2 blood, to-ry shall not exceed the limit of 32 — 42 mm of mercury.
Assessment of oxygenation and transport function of blood. Existence of cyanosis and decrease in pO 2 in an arterial blood (as a last resort — capillary, taken after warming of a finger) it is lower than 80 mm of mercury., and also decrease in oxygenation of an arterial blood lower than 90 — 92% demonstrate development of a hypoxia and demand improvement of conditions of oxygenation or by increase in volume of lung ventilation, or by increase in the oxygen content in the inhaled mix (but no more than 50 — 60%). Insufficient ventilation of the lungs, in addition to a hypoxia, is always expressed by a hypercapnia (pCO 2 it is higher than 45 mm of mercury.). Cyanosis as a symptom of a hypoxia develops only when the hemoglobin content of blood is not lower than datum level.
Assessment of extent of muscle relaxation can be carried out on the nature of relaxation of muscles of a stomach and other muscles, and also on lack of movements of the patient at pain stimulation. More precisely muscle relaxation is estimated by means of elektromiografichesky control of the neuromuscular block according to special indications during N. and for differential diagnosis of a postoperative apnoea.
Elektroentsefalografichesky control of depth of an anesthesia. Due to the distribution of the methods of the combined anesthesia with muscle relaxants which excluded need for deep stages of N. the numerous wedge, symptoms inherent to a monoanaesthesia disappeared, and there was a need of thin assessment of depth and adequacy of anesthesia according to bioelectric activity of a brain. It is established that at N.'s deepening on EEG (see. Elektroentsefalografiya ) the accurate dynamics characteristic of each stage and for each separate anesthetic comes to light. At radio N. allocate five stages, to-rye were brought into accord with classification a wedge, N.'s stages on Gedela (fig. 5, at the left). The stage of II which is characterized by the mixed fast-wave and medlennovolnovy activity, and stage of III (stage of slow waves) allow performance of operations. The stage of IV (a stage of mute electric zones) is characterized by alternation of delta waves with sites of silence and is on border of full fading of electric activity of a brain. It corresponds 3 — to the 4th level of a surgical stage of N. on Gedela. At inhalation of nitrous oxide in the most admissible concentration (80%) in 5 — 10 min. only the stage of transition of an alpha rhythm to medlennovolnovy activity with a frequency of 4 — cycles with increase in amplitude of waves to 50 — 70 mkv can be reached. Changes on EEG at ftorotanovy N. are expressed quite significantly and unlike those, to-rye are observed at N. by ether. Allocate seven EEG-stages of ftorotanovy N. (fig. 5, in the center). The loss of consciousness is observed already in the I stage of a bystry low-voltage rhythm. Muscle relaxation, delay of breath and the termination of the movement of eyeglobes at a steady hemodynamics is observed upon transition of low-voltage bystry activity in medlennovolnovy with a frequency of fluctuations of 4 — sec. with an average amplitude (the II EEG-stage). In the III EEG-stage the bent to arterial hypotension and moderate bradycardia appears. IV and V EEG-stages of ftorotanovy anesthesia are characterized by medlennovolnovy activity of preferential high amplitude and correspond deep a wedge, to stages of N. N.'s maintaining in the V EEG-stage is undesirable, and in stages of VI and VII — is inadmissible.
Patterns of development of barbituric N. in EEG are similar to dynamics of EEG at inhalation anesthesia and pass through activation of electric activity of a brain, delay of frequency of fluctuations and increase in their amplitude with transition to all extended periods of silence (fig. 5, on the right). Emergence is characteristic of barbituric anesthesia spayko-howl activities in the I EEG-stage.
The anesthesia in the emergency surgery
Lack of sufficient information about a condition of the patient, state of shock and a so-called full stomach — the main problems arising during the carrying out emergency N. Zadachey of the anesthesiologist is, whenever possible, bystry and full inspection of the patient for examination funkts, conditions of various bodies and systems. However even at the most imperative need the anesthesiologist has no right to tighten from the beginning of anesthesia at absolute indications to an immediate surgery to obtain additional information on a condition of the patient. The general rule in the emergency anesthesiology is sounding and a full oporozhdeniye of a stomach prior to the beginning of N. Prevention of regurgitation and aspiration of gastric contents is laying of the patient in situation Fowler and use of reception of Selick. Inadmissible in the emergency anesthesiology as well as in other situations, the tamponade of a throat a gauze tampon is during the use of an endotracheal tube without cuff. At patients in state of shock it has to be preferred as N. which does not have significant effect on cordial emission, peripheric vascular resistance and a hemodynamics in general. Most the method of a neyroleptanalgeziya and various methods of the combined anesthesia with addition of morphine, pentazocine, diazepam and other narcotic and sedative drugs conform to these requirements.
The anesthesia in out-patient conditions can be carried out at various diagnostic procedures, preferential endoscopies, in stomatol. to practice at extraction of teeth, and also at their processing for prosthetics, short-term and nontraumatic surgical and ginekol, operations and procedures (opening of abscesses, a scraping of a cavity of the uterus, bandaging, etc.). One of the main requirements, just as in the emergency anesthesiology, is gastric emptying. Other condition is an opportunity for the patient shortly after N. (in 30 min.) to leave policlinic. Apply inhalation mask N. nitrous oxide and Ftorotanum, and also intravenous N. Sombrevinum.
An anesthesia in children's surgery
At N.'s carrying out front masks, respiratory bags and packed beds of narcotic devices, endotracheal tubes, laryngoscopes, syringe needles, tubes for cannulate of vessels, catheters for aspiration shall be the corresponding sizes for each age group of children.
Somatic preparation for N. is directed to possible correction of the available disturbances of the main vital functions of an organism. Psychological preparation is especially important for children over 3 years. The anesthesiologist meets the child in advance, convinces him that an operative measure under N. without serious consequences, sometimes is useful to explain to children of advanced age separate stages of anesthesia — inhalation of oxygen through a mask, intravenous injections. The small child is warned that it will be transferred to other room, will allow to breathe through a mask, «warmed», etc.
Premedication for the children who do not have the expressed allergy most often consists in intramuscular introduction in 15 — 20 min. prior to the beginning of N. of Promedolum and atropine. At children aged up to 6 months Promedolum oppresses breath. Therefore after administration of this drug the child shall be under constant observation. To the children inclined to allergic reactions, in addition appoint to night and in day of operation ataraktichesky, antihistaminic, antipsychotic, somnolent drugs. The good effect of premedication is reached by administration of atropine with thalamonal, a combination of atropine, Droperidolum and diazepam. Very conveniently as premedication to use a combination of atropine and Droperidolum or atropine and diazepam to Ketaminum. In 8 — 10 min. after intramuscular administration of ketamine in a dose of 2,5 mg/kg the child falls asleep, and it can be transferred to the operating room. In essence Premedication using Ketaminum provides not only preparation, but also induction in N. Preliminary administration of diazepam and Droperidolum reduce side effects of Ketaminum — increase in the ABP, tachycardia and convulsive readiness.
Dosages of medicinal substances in milligrams on body weight at children, as a rule, a little big, than at adults. Approximate general doses of the drugs used for premedication to children of various age are given in the table.
Table. The doses of drugs appointed for premedication of children of various age
Introduction N. to children to 5 — most often would be carried out years by means of inhalation anesthetics: Ftorotanum and nitrous oxide. If the child against the background of premedication is guided in a situation, then it is impossible to impose a mask violently. In the beginning it is held at distance 5 — 8 cm on behalf of the child and give through it pure oxygen. It is possible to apply a special mask toy. The mask is gradually brought closer and put on a child's face. During 40 — 60 sec. make inhalation of oxygen, then establish giving 60 — 70 about. % of nitrous oxide and 40 — 30 about. % of oxygen, and in 60 — 90 sec. add Ftorotanum to respiratory mix, gradually increasing its giving from 0,5 to 1,5 — 2,0 about. %. As powerful anesthetic in the absence of Ftorotanum it is possible to use ether to 3 — 4 about. % or cyclopropane 12 — 15 about. %. Against the background of premedication antipsychotic drugs or Ketaminum induction in N. is possible by means of inhalations of nitrous oxide with oxygen in the ratio 2:1.
To children with well-marked veins or when cannulate of a vein was carried out the day before, introduction N. it is possible to carry out 1 — 2% the solutions of hexenal or 1% solution of Thiopentalum-natrium entered intravenously. Introduction intravenous N. can be carried out by Sombrevinum (Propanididum). The drug is administered in a dose 5 — 7 mg/kg to children 8 — 10 years in 5% solution are more senior, and for children of younger age concentration of solution decreases twice. Introduction N. can be received at intravenous administration of hydroxybutyrate of sodium (GOMK) in a dose of 100 — 150 mg/kg. Ofitsinalny 20% solution dissolve 5% of solution of glucose in 10 — 20 ml. The drug is administered slowly within 2 — 4 min. The dream usually comes in 3 — 4 min. after administration of drug.
To children of younger age apply inhalation N. to maintenance of anesthesia nitrous oxide, Ftorotanum and oxygen more often. Shall contain in gas-narcotic mix not less than 30 — 40 about. % of oxygen and no more than 1,0 — 1,5 about. % of Ftorotanum. In need of N.'s deepening it is better to apply narcotic analgetik: Promedolum in a dose of 1,0 — 2,0 mg/kg.
The most adequate anesthesia is provided during the use of high doses of narcotic analge-tics: introduction during operation of Promedolum in a dose of 2 — 3 mg/kg in combination with premedication of GOMK or diazepam or inhalation of nitrous oxide with oxygen. After such N. artificial ventilation of the lungs within 8 — 12 hour is required.
Endotracheal N.'s carrying out in combination with muscle relaxants is shown in the following cases: 1) at operations with opening of a pleural cavity; 2) at big and long operations when good relaxation of muscles is required; 3) at operations at the children who are in a serious condition when possibly disturbance of breath, cardiovascular activity; 4) at head, oral cavity, neck operations; 5) at operative measures when creation of anti-physiological edgewise position, on a stomach with the hung head is necessary; 6) at the majority of operations by the newborn.
Due to the increased vulnerability and danger of the subsequent hypostasis of subcopular space the intubation of a trachea at children needs to be carried out carefully and atraumatic. It is necessary to remember that children of younger age have an epiglottis shorter. The intubation of a trachea is carried out at full relaxation of muscles after introduction of muscle relaxants. Only newborns sometimes can carry out this manipulation under N. without muscle relaxants after the forced hyperventilation of lungs. At children surely apply smooth tubes without cuffs to an intubation of a trachea. Length of an endotracheal tube is equal to about one and a half distances from a corner of a mouth to a lobe of an ear. At operations in an oral cavity the intubation of a trachea in Nov is shown. For this purpose the smooth tube is entered under N. without efforts, it is better through the right closing nasal stroke in an oral cavity, then after introduction of muscle relaxants under control of the laryngoscope carry out it through a glottis. Specially curved intubation nippers of Medzhill are convenient for this manipulation, to-rymi take the oral end of a tube.
Muscle relaxants to children apply to short-term and long relaxation of muscles. Children of younger age are steadier to depolarizing and, on the contrary, are sensitive to not depolarizing muscle relaxants. Single doses (in mg/kg) for children it is slightly more depolarizing muscle relaxants (suktsinilkholin, a leaf-nol, miorelaksin), than for adults. Before an intubation of a trachea the depolarizing Muscle relaxants are entered in a dose of 2 — 2,5 mg/kg, for maintenance of a mioplegiya use doses of 1,0 — 2,0 mg/kg. Usually one or several introductions of the depolarizing muscle relaxants and a moderate hyperventilation of lungs against the background of a surgical stage of N. provide good relaxation of muscles and switching off of breath. Not depolarizing Muscle relaxants (tubocurarine) apply 0,25 — 0,4 mg/kg in a dose. Such dose causes an apnoea for 10 — 20 min. and provides good muscle relaxation within 30 — 40 min. The subsequent doses make V2 — 2/3 initial. As a rule, Muscle relaxants enter intravenously, but when veins are badly expressed, enter them intramusculary or under language. At the same time it is necessary to increase doses of the depolarizing muscle relaxants to 3 — 4 mg/kg. The effect of such introduction occurs in 90 — 120 sec. and proceeds within 5 — 7 min. Tubocurarine is entered intramusculary in a dose of 0,3 — 0,5 mg/kg.
Neyroleptanalgeziya is shown at operations to children with a renal failure, a liver and shifts of the main constants of an organism. In 40 — 60 min. prior to operation intramusculary enter thalamonal in a dose of 0,25 — 1,0 ml, atropine in age dosages. On the operating table intravenously repeatedly enter 0,2 — 0,4 ml thalamonal and, against the background of inhalation of nitrous oxide and oxygen in the ratio 2:1. After introduction of a muscle relaxant carry out an intubation of a trachea. Further the general anesthesia is supported by fractional administration of fentanyl in a dose of 0,3 — 1,0 ml by each 20 — 30 min. and Droperidolum of 2,0 — 5,0 ml with an interval \1/2 — 2 hours. After the termination of inhalation of nitrous oxide at children consciousness is very quickly recovered.
At big and traumatic operations it is reasonable to use Ketaminum for premedication and induction in N., and on this background to carry out endotracheal N. by nitrous oxide with small concentration of Ftorotanum (0,5 — 0,7 about. %). Ketamine N. in pure form (monoanaesthesia) is most shown at urgent operations lasting 40 — 60 min. if carrying out artificial ventilation of the lungs is not required. Advantage of this type of anesthesia is bystry and easy induction in N., lack of hypotensive and emetic effect.
The N at newborns has the features. For premedication it is reasonable to use only atropine in a dose of 0,1 ml. In N. and maintenance of anesthesia apply nitrous oxide with oxygen to induction and Ftorotanum. At traumatic operations it is necessary to reduce concentration of Ftorotanum and to apply Promedolum in a dose of 0,5 — 0,8 mg/kg. At the weakened patients with deficit of weight the intubation of a trachea can be carried out after administration of atropine prior to the beginning of N. U of «strong» newborns with a good muscle tone an intubation of a trachea better to carry out after N.'s beginning and introduction of muscle relaxants.
Very important during N. at the operated child to maintain standard temperature of a body what use the operating table with heating, warming and moistening of gas-narcotic mix and intravenous administration of the solutions warmed to body temperature to. The loss of blood shall be compensated by the similar volume of liquids («a drop for a drop»). Blood loss up to 10% of volume of blood (25 — 30 ml) compensate reopoliglyukiny, Polyglucinum, 5 — 10% solution of glucose. At blood loss of St. 10% of volume of the circulating blood it is necessary to compensate the lost volume blood and blood substitutes in the ratio 1: 1. Pokhmimo compensations of blood loss in addition enter liquid of 4 — 8 ml/kg into hour
the Anaesthesia at advanced and senile age
the Senile age is not considered a contraindication for carrying out N. At planned operation preparation by sedative drugs (diazepam or chlordiazepoxide) begins to be carried out in 2 — 3 days prior to operation. For providing a good night dream appoint hypnotic drugs, it is more preferable barbiturates — phenobarbital, etaminal-sodium, etc. It is not necessary to appoint derivatives of opium (morphine, Omnoponum) the patient of advanced and senile age as these drugs oppress breath and suppress a tussive reflex. The choice of a method of the main anesthesia is defined by a condition of the patient: the serious condition, the poverkhnostny there has to be an anesthesia at sufficient an analgesia Quite often quite satisfactory there is an inhalation of nitrous oxide to oxygen in the ratio 3: 1 or 4:1. Good results are yielded by Neyroleptanalgeziya against the background of inhalation of nitrous oxide with oxygen. At inevitability of use of Ftorotanum its concentration in respiratory mix shall not exceed 1,5 about. %. With success apply steroid N. (viadril, al-gezin) and hydroxybutyrate of sodium. For ensuring postoperative anesthesia administration of pentazocine is reasonable (fortrat).
The anesthesia in field
the Anaesthesia in field conditions for the first time was carried out by N. I. Pirogov in 1847 during military operations of the Russian army in the Caucasus (ether, and then chloroform). In war of 1914 — 1918, despite the advantages of a local anesthesia revealed by then, in field surgery generally used methods of the general anesthesia. As means for it served chloroform, ether, Aether chloratus and a combination of these anesthetics. In World War II approach to the choice of anesthesia in armies of the being at war countries was various. The Soviet field surgeons applied preferential local anesthesia, and at the beginning of war resorted to the general anesthesia only in 15 — 20% of operations. By the end of the Great Patriotic War use of methods of the general anesthesia increased, and N. was applied in 30 — 35% of operations. In armies of the USA and England from the very beginning of war of the general anesthesia the main place was allocated, and it was generally provided specially podgotov-lennymn with doctors and paramedical staff.
During the post-war period in connection with successful development of anesthesiology and regular and organizational registration of this specialty in military medicine premises for use of more perfect methods of the general anesthesia appeared. In modern conditions for carrying out it in most armies are provided in the state field to lay down. institutions anesthesiologists and anesthetists. On equipment the special sets, narcotic, respiratory devices and nek-ry other technical means necessary for carrying out the general anesthesia are accepted. Considerably the arsenal pharmakol, means for N. increased: ether, Ftorotanum, trichloroethylene, nitrous oxide, barbiturates (hexenal and Thiopentalum-natrium), drugs for a neyroleptanalgeziya, Muscle relaxants of long and short action, etc.
In field conditions the general anesthesia is shown at surgical treatment of extensive wounds of soft tissues, at operations for the majority of the getting wounds and the closed damages of bodies of chest and belly cavities, widespread burns, wounds with injury of large bones and joints, the main vessels, at amputations of extremities, large neurosurgical and maxillofacial operations and nek-ry other interventions, and also at difficult and painful bandagings. The N is shown in cases when at struck before operation there are disturbances of the vital functions (breath, blood circulation) or these disturbances can arise during operation, and also at the operations undertaken before the removal struck from state of shock.
Distinctive feature of N. in field conditions is relative unpreparedness struck to N. and dependence of methods and means anesteziol, the help from a medical situation, a stage of medical evacuation and character of the task solved by a stage. At a stage of the qualified surgical help simple methods H. — mask and intravenous with spontaneous breath prevail or at artificial ventilation of the lungs by air; on ethane of the specialized surgical help — the combined methods of the general anesthesia with artificial ventilation of the lungs by the gas-narcotic mix managed by ganglionic blockade, a hypothermia etc.
At the choice of a method - N. and technology of its carrying out original positions remain in force, to-rymi anesthesiologists in peace time are guided. Along with it the features following from an originality of working conditions field are considered to lay down. institutions. Preference is given simpler, but to rather effective methods allowing to provide quickly necessary degree of anesthesia and quickly to awaken struck after operation. At the choice and carrying out anesthesia it is necessary to take into account that many struck arrive on the operating table in state of shock, with big blood loss, respiratory insufficiency. At the same time the anesthesiologist has no sufficient time for comprehensive assessment of their state and preoperative preparation, is limited in the choice pharmakol, means and technical providing anesthesia.
Premedication in most cases should be carried out on the operating table. And doses and time of an injection of the anesthetics and sedative drugs received struck at the previous stages are considered. In the absence of the expressed their residual action intravenously enter morphine (10 mg) in combination with atropine (0,5 — 0,8 mg) and isopromethazine (25 mg) or Droperidolum (2,5 — 5,0 mg).
The main anesthetics for induction are barbiturates of short action. Hexenal or Thiopentalum-natrium enter in a dose 200 — 400 mg into 1% or 2% solution. Heavy struck, having hypersensitivity to barbiturates, the drug needs to be administered more slowly and in a smaller dose. For induction in N. with success it is possible to use inhalation of Ftorotanum in combination with nitrous oxide or azeotronny mix.
Against the background of rather steady indicators of gas exchange and blood circulation the majority of short operations can be executed at independent breath struck without carrying out a transfusion of liquid and introduction any additional pharmakol, means. As the only or main anesthetic at the same time hexenal or Thiopentalum-natrium, ketamine, constant boiling mixture, Ftorotanum or its combination with nitrous oxide can be used.
At long and considerable operations on volume use endotracheal) a method of the general anesthesia in combination with artificial ventilation of the lungs is reasonable. At the same time tyazhelopora-zhenny with frustration of a hemodynamics and breath introduction pharmakol, the funds allocated for improvement of blood circulation, gas exchange and correction of possible metabolic frustration can be shown. Means of the choice for maintenance en to tracheal N. are drugs for a neyroleptanalgeziya (fentanyl, Droperidolum) in combination with insufflation of nitrous oxide, ether or constant boiling mixture. At the combined radiation defeats it is more preferable neingalyatsioiny methods H.; doses of anesthetics and muscle relaxants should be reduced by 15 — 20%.
In field conditions cases when the persons which do not have in this field of special preparation are forced to carry out N. are not excluded. It is under such circumstances reasonable to use the simplest, though imperfect, radio N.'s method by means of Esmarkh's mask or the narcotic device as became during the Great Patriotic War.
From additional materials
ANAESTHESIA (— the state which is artificially caused in the pharmacological or electric way followed by switching off of consciousness, suppression of painful sensitivity, relaxation of skeletal muscles and oppression of reflex activity. Absolute contraindications to an anesthesia do not exist. Than the reference state of the patient is heavier, especially the anesthesia allowing to support reliably a homeostasis of an organism in the conditions of an operational stress is shown.
Contraindications in specific clinical situations, first of all, are connected with the kliniko-pharmacological characteristic of anesthetic. The optimum anesthesia assumes exhaustive assessment of a condition of the patient before an operative measure, a right choice of a type of an anesthesia and means for its implementation at all stages from premedication and an introduction anesthesia till the period of maintenance and escaping of anesthesia. The main kliniko-pharmacological data on inhalation and not inhalation anesthetics are provided in tables 1 and 2: the physical and chemical characteristic, pharmacological action, the main indications and contraindications to use, side effects and complications, the main forms of release and ways of storage.
Table 1. The MAIN SVEDANIYA'S KLINIKO-FARMAKOLOGIChESKE ABOUT INHALATION ANESTHETICS
Table 2. The MAIN KLINIKO-FARMAKOLOGIChESKIE of the DATA On NEINGALYaTsI0NNYH ANESTHETICS
Bibliography: Bunyatyan A. A., Ryabov G. A. imanevicha. 3. Anesthesiology and resuscitation, M., 1977; Vishnevsky A. A. and Schreiber M. I. Field surgery, M., 1975; D and r and - N I am T. M. N and about l about in the h and N with to and y V. B. Mechanisms of an anesthesia, M., 1972; About r about in I. S. General anesthesia, M., 1964; Manevich A. 3. Pediatric anesthesiology with elements of resuscitation and an intensive care, M., 1970; Experience of the Soviet medicine in the Great Patriotic War of 1941 — 1945, t. 3, p.1, page 492, M., 1953; The Guide to anesthesiology, under the editorship of T. M. Darbinyan, M., 1973; Uvarov B. S. Anesthesiology help in conditions of modern war, Voyen. - medical zhurn., No. 10, page 25, 1966; Atkinson R. S. a. Lee J. A. Synopsis der Anasthe-sie, B., 1978; Emergency war surgery, Washington, 1975; Kinderanasthesie, hrsg. v. W. Dick u. F. W. Ahnefeld, B. u. a., 1978, Bibliogr.; A practice of anesthesia, ed. by W. D. Wylie a. H. C. Churchill-Davidson, L., 1972; Stephens K. F. Some aspects of anesthesia in war, Med. Bull. US Army Europe, v. 20, p. 170, 1963.
G. A. Ryabov; W. A. Michelson (it is put.), B. S. Uvarov (soldier.).