On the action and use of aconitia / by John Harley.

  • Harley, John, 1833-1921.
Date:
[1872?]
Catalogue details

Licence: Public Domain Mark

Credit: On the action and use of aconitia / by John Harley. 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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    4. The action of the alkaloid on the sensory function appears to be coextensive and coequal with that on the motor function, the area for intense action having the same limits, beyond which the ansesthesiant action rapidly diminishes in intensity. Thus, while the head and neck are deprived of sensation, the rest of the surface is only partially affected, and the sensibility of the lower parts of the body only slightly or not at all disordered. 5. Apart from the derangement of accommodation, from spasm or enfeeblement of the muscular apparatus of the eye and the ear, the senses of sight and hearing were unaffected; the latter, indeed, was apparently wholly unaffected. There was no evidence of any impairment of smell. Taste was, without doubt, greatly disturbed, both on account of its relation to common sensation, and of the deep implication of the fifth nerve. 6. Beyond the slight depression of function resulting in somnolency (after medicinal doses and in the intervals of the paroxysms which follow poisonous ones) aconite has no direct influence on the brain, and the effects produced by asphyxia have usually only a brief duration at the end of a paroxysm or immediately preceding the death of the animal. The intense distress of impending suffocation produces, however, a total disregard for everything else but the desire for relief, and thus the animal rages frantically about as if actually delirious. 7. The sympathetic nerve is unaffected. At the moment of death the pupils dilate vigorously; and after death the heart may continue to pulsate,1 or, if the right heart be arrested by distension, its action may be revived by depletion. The con- tracted left heart is still, only because it is empty. From the evidence adduced, it is I think, conclusively proven that the heart is only secondarily affected, and as a consequence of the respiratory difficulty. If I could scandalise common sense by belief in the idea that the heart was under an inhibitory influence conveyed to it by the cardiac branches of the pneumogastric, I might argue that the foregoing obser- vations go very far to disprove the existence of such a function, unless I could persuade myself that the cardiac branches of the 1 This I find is strictly in accordance with Dr. Fleming’s observations : ‘Inquiry into the Physiological and Medical Properties of Aconite/ p. 91, et seq.
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