Ethyl chloride (aethylis chloridum), C2H5C1, is a highly volatile and inflammable gas, prepared by the action of hydrochloric acid upon absolute alcohol. It condenses to a liquid at 13° C. (55.4° F.), and is kept thus in sealed tubes under pressure. These tubes are made with a minute pin-hole nozzle covered with a cap and on removal of this cap the liquid issues with some force in the form of a very fine spray.

Local Action

On striking the warm skin it vaporizes with such rapidity that it freezes the tissues. This makes a local anesthesia of a moment's duration, during which a small cut, as of an abscess or infected finger, or a puncture, as in paracentesis of thorax or abdomen, may be made without pain. The freezing of the tissues sometimes results in sloughing. The spray is sometimes also employed in facial neuralgia.

Systemic Action

To produce general anesthesia ethyl chloride is vaporized into an inhaler, the patient being brought into a state of anesthesia in from one to two minutes without any local irritation, but with incomplete muscular relaxation. Recovery when the anesthetic is stopped is almost immediate, and because of this it is a difficult task to maintain the anesthesia for any length of time. (Whiteford has kept the patient under ethyl chloride for thirty-five minutes, and Wiessner for fifty minutes, by pouring 2 or 3 c.c. on the mask every two minutes; Montgomery and Bland, for fifty-four minutes.)

On the average, 5 gm. will produce unconsciousness and abolition of pain in one or two minutes, and maintain it for ten minutes, but the reflexes are not depressed to the point of complete muscular relaxation. Because of its concentrated form and ease of transportation, it being a liquid in glass tubes, and because of its cheapness in the dose used, it has been employed in operations of short duration, in dentistry, and as a preliminary to ether anesthesia. Connell says that severe headache, nausea, repeated vomiting and severe prostration are not infrequent, that "a delayed collapse has added a number of fatalities to the score of this anesthetic," and that "on the whole, ethyl chloride meets no necessity in anesthesia which cannot be better supplied by ether, chloroform, or nitrous oxide."

Ethyl bromide resembles ethyl chloride in its action, but is not quite so volatile, and its use has been abandoned.

Mixtures of these anesthetics should not be employed.