REFRIGERANTS. This term is applied in medicine both to internal and external cooling remedies. The medicines of this class prescribed for internal use cause a refresh ing feeling and a sensation of coolness throughout the system, although they do not in reality diminish the temperature of the body. Their principal use is in the treatment of febrile and inflammatory affections, in which the benefit they produce appears to depend on the fact, that their direct action on the coats of the stomach occasions, by nervous sympathy, a temporary reduction in the force of the circulation. They likewise have the power of allaying gastric irritability and the morbid sensations of heat and thirst. The following are the refrigerants in most common use for internal administra tion: citric and tartaric acids taken into combination with bicarbonate of potash as effervescing draugItti, ripe oranges, lemons (in the form of lemonade q.v.), chlorate of potash (ten grains dissolved in water, and sweetened with syrup, to be taken every second hour), and nitrate of potash, which may be taken in the same manlier as the chlorate, or 113 niter-whey, which is prepared by boiling two drams of niter in a pint of new milk; the strained milk may be given frequent doses of two or three ounces. Many continental physicians regard oxalic acid in the form of lemonade as the best of all the refrigerants. Its poisonous character must not be forgotten, but five grains dis solved in half a pint (or more) of water may be taken in divided doses in the twenty four hours with perfect safety.
The following remarks on the external application of refrigerants are for the most part condensed from Mr. Simon's able article on" Inflammation" in Holmes's System of Surgery. Cold, continuously applied, is the sedative of every vital manifestation; and in theory, it may be regarded as being in direct and essential opposition to the causes of inflammation; and as it is thus an antidote to the causes of inflammation, rather than a remedy for the resulting changes, so, in order to get full advantage from its use, it should be employed from the moment when these causes begin to operate. Cold is of great value in the treatment of wounds, especially such as are made in surgical opera tions. The local temperature can be thus Continuously moderated, care being taken that it is not too much reduced, so as to occasion gangrene. Under the effective use of cold (together, of course, with absolute rest of the parts), many a knee-joint, whether wounded accidentally or by a surgical operation, recovers without permanent injury In most cases local cooling is best effected by water of the desired temperature. Cloths
wetted with it are spread over the surface which is to be acted on, their original low temperature being retained either by their being continuously dripped upon by means of a bundle of threads inserted in a reservoir of cold water, and acting like a siphon. of by their being frequently re-wetted or Changed. Their surface should be exposed as freely as possible to the air, so as to secure ample space for evaporation. In cases where great cold is required—as, for example, in cases of strangulated hernia, of inflammation of the brain and its membranes, or of fever with well-marked cerebral sympfoms bladders of pounded ice are preferable to wetted cloths. Both as regards the degree of cold and the period of its application, the surgeon should to a considerable degree be influenced by the sensations of his patient. When its application gives comfort, it is almost certain to be doing good; and in most cases where it gives discomfort., it is doing harm.
A. notice of the external use of refrigerants would be imperfect without a reference to the memoir of Dr. Esmareh, professor of surgery in the university of Kiel, On the 1164 of Cold in Surgery, translated by Dr. Montgomery for "the new Sydenham society,' in the year 18G1. His mode of application is by means of India-rubber bags filled with ice, snow, or some freezing mixture; or of thin iron-plate reservoirs of cold water, made by means of a mold of gutta-percha to fit any inflamed part. In a case of "chronic purulent inflammation of the knee-joint," the ice-bags were continuously applied for 12 weeks. Dr. James Arnott's investigations on "Local Antesthesia by Cold," in the Medical Times for the years 1854-5-7, and Dr. Chapman's method of treating nervous diseases by the application of cold to the spine, as recorded in his Functional Diseases of 1Vomen and elsewhere, require also a passing reference.
The application of cold, either through the medium of air or water, to the body gen erally is a subject of great importance. The use of cold air is especially seen in febrile cases, in which the physician directs the sick-room to be kept cool, and the patient (unless in exceptional cases) lightly clothed. Mr. Paget reports that the most successful eases of pyemia that have fallen under his observation Were those in which the patients were freely exposed to the air. The value of baths and cold effusions is noticed in the articles BATH and IIYDROPATITY. In addition to what is there stated, it is important to know that prolonged inunersiou in water as warn' as 95° Fahr. may be the means of reducing febrile temperature.