On digitalis : with some observations on the urine / by T.L. Brunton.

Date:
1868
Catalogue details

Licence: Public Domain Mark

Credit: On digitalis : with some observations on the urine / by T.L. Brunton. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    We see that the pulse in Daniel G. presents the same characters. From these facts I believe we cannot avoid the conclusion that it exerts a slowing action directly on the heart. In poisoning by digitalis the force of the pulse bears no relation to that of the heart's impulse; for while the latter is sti'ong and hammering, the former is small, thready, and nearly imperceptible. Marey1 gives this law, The force of the pulse is not in correspondence with the energy of the ventricular contraction, but is regulated by the state of the circulation in the ultimate ramifications of the vascular system. The force of the pulse increasing with the arterial • .... ■ J>v\ aXc tension and diminishing along with it, the pulse that occurs in digitalis poisoning is due to the lowtension; and this, again, as we shall see hereafter, probably depends on the relaxation of the capillary system, and the rapid transit of blood through it. On the Heart.—Having seen that digitalis exerts a prim- ary influence on the heart, the question now arises, What is this action] And, first, as to its force. Does digitalis weaken the muscular power of the heart 1 Does it increase it ? or does it do neither, but simply lessen the number of pulsations, either by diminishing its irritability, and so rendering it less sensitive to the stimulus of the blood, or by increasing the power of the regulating part of the nervous system ] Very different opinions have been held on these points by different authors. Stannius2 says, that after the injection of | a strong dose of digitalis, there is at once a surprising feeble- ness of the cardiac pulsations, which soon changes into paraly- sis of this organ, at first partial and then complete ; and this he attributes to paralysis of its muscular contractility, rather than to any affection of its nervous arrangements. 1 Marey, Physiol. Med. de la Circ. de Sang, p. 235. 2 Stannius quoted by Homolle and Quevenne, p. 234.
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