Origin. - A liquid composed of about 96 per cent. by weight of absolute ether or ethyl oxide, [(C2H5)2O = 73.52], and about 4 per cent. of alcohol containing a little water.

Description and Properties. - A transparent, colorless, mobile liquid, having a characteristic odor and a burning, sweetish taste. Specific gravity, 0.716-0.717 at 250 C. (770 F.). Soluble in about ten times its volume of water, with slight contraction of bulk. Miscible, in all proportions, with alcohol, chloroform, petroleum, benzin, benzene, and fixed and volatile oils.

Ether is highly volatile and inflammable, its vapor, when mixed with air and ignited, exploding violently. It should be kept in well-stoppered containers, preferably in tin cans, in a cool place, remote from lights or fire.

Dose, 15-40 minims (1.0-4.0 Cc.) [15 minims (1 Cc), U. S. P.].

Official Preparations

Splritus aetheris - Spiritus aetheris - Spirit of Ether. - Dose, 1/4-1 fluidrachm (1.0-4.0 Cc). _ _

Spiritus aetheris Compositus - Spiritus aetheris Compositi - Compound Spirit of Ether (Hoffmann's Anodyne). - Ether, 325; alcohol, 650; ethereal oil, 25 parts. Dose, 5-60 minims (0.3-4.0 Cc).

Antagonists and Incompatibles. - The stimulant and anodyne action of ether is antagonized by the arterial sedatives, the tetan-izing alkaloids, strychnine, picrotoxin, etc.

Synergists. - The arterial and cerebral stimulants, chloroform and other anesthetics, and alcohol.

Physiological Action. - Externally and Locally. - Ether when applied to the skin produces intense cold by its rapid evaporation. If it is confined and its evaporation prevented, great irritation is caused. By spraying a part with ether it becomes quickly frozen, marked local anesthesia being produced thereby.

Applied to mucous membranes, it creates considerable irritation, especially of the fauces and respiratory tract when inhaled.

Internally. - Digestive System. - It is a carminative, increasing peristalsis and the secretions from the pancreas and the salivary and gastric glands, at the same time dilating the vessels of the stomach.

Circulatory System. -When taken into the stomach, ether re-flexly stimulates the heart in a manner similar to that of alcohol, raising arterial tension by increasing the force and frequency of the heart's action.

Ether stimulates the heart and increases the blood-pressure when inhaled. It is a diffusible, rapid, and reliable cardiac stimulant.

Respiratory System. - Medicinal doses stimulate and poisonous doses paralyze the respiratory center.

Nervous System. - Ether first occasions a considerable degree of excitement, due to the direct action of the ethyl upon the cerebral cortex. Its action on the cerebrum is similar to that of alcohol, and need not be recapitulated. The action is much more rapid. The stages are all compressed and hence somewhat accentuated. Thus the excitement of the second stage is distinctly comparable with the incoherence and exuberance of the partially intoxicated individual.

Respiration is frequently arrested at the beginning of ether-inhalation, owing to reflex spasm arising from irritation of the peripheral ends of the vagi and trigemini. As the inhalation is continued the breathing becomes deeper and slower from stimulation of the respiratory center. This part of the nervous system may, in fact, become exhausted from over-stimulation, when the respirations are slow and shallow.

In fatal cases of ether-narcosis the respiration is usually arrested before the cessation of the heart's action.

Absorption and Elimination. - Ether is rapidly eliminated, chiefly by the lungs, but also by the kidneys, which are often considerably irritated by the process.

Temperature. - The prolonged administration of ether produces a great reduction of temperature - doubtless due to the depression of the circulation and respiration and the rapid evaporation of the drug, chilling the body and lungs, rather than to any direct action upon the nervous mechanism presiding over the heat-centers.

In brief, the action of ether when inhaled may be divided into 3 stages for purposes of description. They merge one into another, and in many individuals great variations exist. These may be termed the stage of (1) impaired consciousness, (2) excitement, (3) anesthesia. At first a sensation of choking and irritability of the respiratory mucous membrane is experienced. A greatly increased activity of the salivary glands follows, accompanied by a sensation of pricking or tingling of the hands and feet. The conjunctiva is injected, the face is flushed, the veins of the neck are distended, and there is experienced a peculiar feeling of lightness, together with the beginning of impairment of consciousness. Seeing and hearing are altered, slight insensibility is present, and is sometimes utilized for slight operations. Following this first short period the stage of excitement is usually ushered in by muscular twitchings or muscular struggles. The patient may yell, laugh, cry, curse or pray, struggle or become pugilistic or sometimes amorous. The respirations are usually quickened and irregular from the struggling, and the pulse is rapid and irritable. The pupils are usually dilated.

The stage of anesthesia is usually indicated by muscular relax-ation. The patient becomes quiet. The breathing becomes more regular and slower; the heart becomes steadier and slower. The reflexes are abolished, the genital and conjunctival reflexes last involved, and complete anesthesia and unconsciousness with mildly contracted pupils indicate the full action of the anesthetic.

If the inhalation be discontinued before a toxic quantity of ether has been administered, consciousness gradually returns - in some cases almost at once, although some loss of sensation and muscular weakness remain for a while.

The return of consciousness is usually accompanied by retching and vomiting - often by severe rigors, unless care has been taken to keep the patient warm. Great excitement not infrequently attends this stage of etherization.