ETHYL ETHER

From Big Medical Encyclopedia

ETYLOVYY EFYR (synonym: diethyl ether, sulphuric ether, ether) — the most famous representative of ethers who is applied in medicine as anesthetic for external use, preparation of tinctures and extracts. In practice of chemical and biochemical laboratories E. aa. it is used for extraction and as the environment for carrying out nek-ry reactions. In the industry E. aa. apply in production of a film and film, smokeless powders, glues on the basis of a collodion. During the receiving and use E. aa. it can represent professional harm.

C2H5OC2H5 ethyl ether — easily evaporating, colorless mobile liquid with a peculiar (radio) smell, density at 20 ° 0,7135; * °kip 34,48 °; g°pl — 116,2 °; coefficient of a refraction at 20 °

1,3526, water solubility at 20 ° 6,5%. Ethyl ether dissolves at 25 ° apprx. 1,5% of water, about a cut it forms the constant boiling mixture containing 98,74% of ethyl ether with * °kip 34,15 ° (see. Constant boiling mixtures). AA. aa. beyond all bounds mixes up with alcohol (see) and the majority of other organic solvents (see), well dissolves many organic compounds (see), including fats (see), pitches, etc. Couple E. aa. explosive mixes with air (concentration limits of explosibility of 1,9 — 48%), temperature of flash 43 °, self-ignition temperature 180 ° form. Owing to an easy inflammability and a volatility E. aa. constitutes considerable danger in the fire relation that limits its technical use and shall be considered in laboratory and medical practice.

In the chemical relation E. aa., as well as all ethers (see), it is quite inert. It forms connections (salt of oxonium) with substances of acid character thanks to what E. aa. substantially we will dissolve in concentrated to-takh (sulfuric and salt) and well dissolves hydrogen chloride. AA. aa. reacts also with bromine and salts of nek-ry metals. During the heating with galogenovodorodny to-tami it it is split: (C2H5)20 + NVG —>

- *s2n5vg + C2H5OH. Ethyl ether is steady against effect of alkalis (see) and alkali metals (see); sodium metal is applied to drying E. aa. As well as other ethers, AA. aa. gradually is oxidized oxygen of air with formation of peroxide substances and acetic aldehyde (see Acetaldehyde). Contained in E. aa. peroxides (see) are explosive and can be a cause of explosion at its distillation therefore in overtaken E. aa. it is necessary to control the content of peroxides by tests with the acidified solution of potassium iodide or with solution of salt of bivalent iron and potassium thiocyanate. Formation of peroxides is slowed down at storage E. aa. in the place protected from light, in bottles from dark glass and at a low temperature.

In the industry E. aa. make heating of alcohol with the concentrated chamois to - that (from here the name «sulphuric ether» which was widely occurring earlier) or catalytic dehydration of alcohol: 2C2H5OH — * (C2H5)20 + H20. Besides, ethyl ether is a by-product in production of synthetic ethanol.

Qualitative test on E. aa. its turning into acetic aldehyde under the influence of ferrous sulfate and hydrogen peroxide, for definition can serve E. aa. in air and in blood use its oxidation by potassium bichromate; however both of these methods are not specific. Modern methods of definition of ethyl ether, including in biological material, are based on gas and highly effective solution chromatography (see).

AA. aa. in the concentration exceeding admissible it is toxic. A wedge, a picture at acute poisoning E. aa. it is characterized by excitement with the subsequent drowsiness and a loss of consciousness. Hron. poisoning E. aa.

it is shown by a loss of appetite, nausea, apathy, drowsiness (is more rare — sleeplessness). At the same time note full intolerance of alcohol. Frequent steam inhalation E. aa. causes accustoming to it.

ETHYL ETHER 375


Ground mass E. aa., coming to a human body, it is allocated in not changed look, and nek-paradise a part is metabolized to acetic aldehyde, contents to-rogo in blood in this case is close to the level which is observed after administration of alcohol.

Description of properties E. aa. as professional harm, first aid and emergency treatment at poisoning E. aa. — see Ethers.

Use in anesthesiology. In the medical practician E. aa. generally use for an inhalation anesthesia (see), as means for the monoanaesthesia or substance which is a part of multi-component gas-narcotic mixture for an anesthesia, inhalation a cut is carried out through an endotracheal tube (see the Anaesthesia). AA. aa. represents classical strong anesthetic with the expressed width of therapeutic action and powerful narcotic, analgetic and mioplegi-chesky effect. The relaxation of skeletal muscles caused E. aa., is not eliminated with antikholineste-different means (see). Ethyl ether strengthens the muscle relaxation caused by kurarepodobny substances (see), antibiotics from group of aminoglycosides and nek-ry other antibiotics (see Muscle relaxants).

A respiration rate and minute volume at inhalation E. aa. increase that is connected with irritation of irritantny receptors of respiratory tracts couples E. aa., under action to-rykh secretion of salivary and bronchial glands also considerably amplifies. Influence E. aa. on cordial emission, heart rate and the general peripheric resistance depends on a grade of anesthesia (see). At the same time perhaps sharp increase in the ABP owing to increase in content of adrenaline (see) and noradrenaline (see) in blood. AA. aa. does not cause sensitization of a myocardium to aritmogenny action of catecholamines (see). In general E. aa. is one of the safest anesthetics from the point of view of influence on blood circulation. Indicators of coagulability of blood against the background of an anesthesia E. aa. do not change. AA. aa. causes relaxation of a myometrium.

At the choice E. aa. as anesthetic it is necessary to consider its sympathomimetic action, ability to raise a tone of vessels, to strengthen cordial activity, to raise excretion of catecholamines, concentration in blood of sugar, milk and pyroracemic to - t, to increase consumption by an organism of oxygen, to oppress motor and secretory functions went. - kish. path.

AA. aa. as anesthetic can be applied without oxygen by means of simple devices (see the Anesthetic inhaler).

Dosage E. aa. depends on a way of supply of drug and a condition of the patient. Most precisely concentration E. aa. in the inhaled gas-narcotic mix it is regulated at half-open system. At a mask anesthesia concentration of vapors E. aa. in the inhaled gas-narcotic mix gradually increases with

1 — 2 about. % to 12 — 20 about. % within 10 — 20 min. before development of a narcotic dream with the subsequent reduction of concentration of ethyl ether to 5 — 10 about. % for maintenance of an anesthesia.

At interruption in supply E. aa. on any grade of anesthesia the wedge, a picture is characterized by gradual recovery of reflexes, a tone of muscles, sensitivity and consciousness, thus all grades of anesthesia almost upside-down repeat. At the same time awakening happens slowly within several hours and is followed by effect of an analgesia.

At an endotracheal anesthesia when the introduction not inhalation anesthesia and muscle relaxants are applied, the optimum depth of etherization can be supported by small concentration of ethyl ether (2,5 — 3,5 about. %) under control of a pupillary reflex and condition of a hemodynamics, and more precisely — by means of an electroencephalography.

Negative properties E. aa. are the slow introduction to a surgical grade of anesthesia which is followed by the period of excitement, long awakening, irritation of a mucous membrane of respiratory tracts, ability to cause reirritation of sympathoadrenal system (see), disturbance of metabolic processes, and also potential of explosion of drug. Therefore as means for a monoanaesthesia E. aa. apply seldom, use it for carrying out the combined (multicomponent) general anesthesia in combination with inhalation more often (nitrous oxide, Ftorotanum) and not inhalation (drugs barbituric to - you, etc.) anesthetics and muscle relaxants.

Complications at etherization can be observed both during an anesthesia, and in the postoperative period (see). Their character and weight depend on a way of the general anesthesia (a masochyy, endotracheal anesthesia), the applied rebreathing system (see. Inhalation anesthesia), condition of the patient, experience of the anesthesiologist. At a mask anesthesia the laryngospasm can develop in stages of an analgesia (see), the bronchospasm (see) because of irritant action E is more rare. aa., cases of a cardiac standstill owing to a vago-vagal reflex are described. In the II grade of anesthesia (a stage of excitement) asphyxia owing to vomiting or regurgitation, obstruction of respiratory tracts by slime, in the III stage is dangerous (surgical) at overdose E. aa. retraction of language, oppression of the respiratory and vasomotor centers is possible. In a stage of awakening (according to I. S. Zhorov) vomiting, in the early postoperative period — nausea, a tracheobronchitis, laryngitis, paresis of intestines, oppression of function of a liver, disturbance of acid-base equilibrium can develop (metabolic acidosis). AA. aa. causes vasoconstriction of kidneys, reduction of intensity of glomerular filtering and decrease in amount of the emitted urine owing to increase in secretion of vasopressin (see).

Prevention of complications of etherization first of all consists in strict observance of rules of carrying out all stages of the general anesthesia taking into account contraindications. The complex of premedication shall include drugs of vagolytic, antihistaminic and sedative action.

At treatment of the complications connected with etherization depending on their character appoint the means stimulating breath, cordial activity, eliminate obstruction of respiratory tracts, also blood substitutes transfuse blood, apply artificial ventilation of the lungs, a cardiac massage.

There are no absolute contraindications to use of etherization. Relative contraindications are acute respiratory diseases, increase in intracranial pressure, a diabetes mellitus and other states which are followed by acidosis and also a hyperthyroidism, a serious illness of a liver and kidneys, heart failure, a myasthenia. Etherization is contraindicated at operations with use of electrothermic coagulation.

Drugs of ethyl ether. To the drugs E used in medical practice. aa. carry the Aether anaesthesicus, an Aether anaesthesicus stabilized and ether medical.

Aether anaesthesicus (Aether pro narcosi; synonym: Aether anaes-thesicus, Anesthetic Ether; joint venture. Б). Form of release: hermetically the corked bottles from dark glass with a capacity of 100 and 150 ml with the metal foil enclosed under a stopper. Storage: in the cool place protected from light, far from fire.

The Aether anaesthesicus stabilized (Aether pro narcosi stabilisatus; joint venture. B) on the properties it is similar to an Aether anaesthesicus, however addition of the stabilizer — antioxidant (see Antioxidants) — extends a period of validity of drug. Form of release: hermetically the corked bottles from orange glass with a capacity of 140 ml.

Ether medical (Aether medicinalis; joint venture. B) represents less purified drug, than an Aether anaesthesicus. For an anesthesia it is not used. Ether medical is used for external use, and also for preparation of tinctures and extracts. Sometimes appoint inside at vomiting. The highest doses for adults inside: one-time 0,33 ml (20 drops), daily 1 ml (60 drops). Form of release: large bottles of various capacity. Storage conditions are same, as well as at storage of an Aether anaesthesicus.

Bibliography: At N I would be t I A. A. N, Rya

of b G. A. and Manevich A. 3. Anesthesiology and resuscitation, page 184, M., 1984; Gadaskina I. D. and Filov V. A. Transformations and definition of industrial organic poisons in an organism, page 205, D., 1971; M and sh to about fi-sk y M. D. Pharmaceuticals, t. 1, page 11, M., 1984; The Guide to anesthesiology, under the editorship of T. M. Darbinyan, page 63, M., 1973; The Reference book on an anesta

of a ziologiya and resuscitation, under the editorship of

A. A. Bunyatyana, page 144, M., 1982;

V. I Pods. General surgery, page 100, M., 1983; T e r N e y And. Modern organic chemistry, the lane with English, t. 1, page 439, M., 1981; Lee J. A. a. Atkinson R. S. Synopsis der Anasthesie,

B., 1978; The pharmacological basis of therapeutics, ed. by A. G. Gilman a. o., N. Y., 1980.

A. I. Tochilkin; P. H. Alyautdin (pharm.), O. A. Dolina (anest.).

Яндекс.Метрика