The influence of cocaine, atropine, and caffeine on the heart and bloodvessels / by H.G. Beyer.

  • Beyer, Henry Gustav, 1850-1918.
Date:
1885
Catalogue details

Licence: Public Domain Mark

Credit: The influence of cocaine, atropine, and caffeine on the heart and bloodvessels / by H.G. Beyer. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    gists for several years to come in order to bring the problem to a final solution which will prove satisfactory to all. A priori, the anaesthesia produced by cocaine might be due to its directly paralyzing influence on the terminal filaments of sensory nerves and nerves of special sense, the production of anassthesia being also accompanied by a temporary abolition of special sense, at least as far as the mouth, ear, and nose are concerned. By many, no doubt, it has been sup{)osed that a stimulating influence on the sympathetic is the cause underlying both the production of anaesthesia as well as that of pupillary dilatation, and, indeed, the probability in favor of such action is very great, and would explain everything very satisfactorily if experiment would prove it. By still others, the anaesthesia has been thought to be probably due to a temporary contraction of the capillaries, in consequence of which the tissues are, for the time being, deprived of their normal blood supply and thus rendered insensible to external impressions. The latter view has been advanced by Dr. Edward R. Squibb, in his Ephemeris, January and March, 1885, and has a great deal in its favor. A certain amount of blanching of those mucous surfaces to which cocaine has been applied is almost invariably present by the time antesthesia has become established. A slight amount of capillary contraction may also be seen by any one in the expanded frog's web after the direct application or hypodermic injection of cocaine, more marked when the capillaries had previously been irritated and an artificial dilatation thus been produced. It was with a view of tlirowing, if possible, some additional light on the influence of cocaine on the circulatory apparatus that the following obser- vations were undertaken. Soon after beginning my experiments with cocaine on the heart of the terrapin I was very much impressed with the great similarity of the effect produced by cocaine and atropine. The action of the latter drug had formed the subject of some of my previous experi- ments, but, on account of the supposed peculiarity of some of them, they were not all published at the time. This striking similarity made me subject atropine to renewed and more extended investigation with results to be referred to hereafter more in detail. Caffeine was also afterwards taken up in addition to these because of the supposed similar action. All the experiments here described were made in tlie laboratory of the Museum of Hygiene under the auspices of the Bureau of Medi<!ine and Surgery, Navy Department, Washington, D. C. My thanks are, tiiere- fore, due to the chief of that bureau, Surgeon-General Francis M. Gunnell, and also to Medical Director John M. Browne and Surgeon C. H. White, for much kindness in facilitating my work.