A manual of the practice of medicine / by George Hilaro Barlow.

  • George Hilaro Barlow
Date:
1861
Catalogue details

Licence: Public Domain Mark

Credit: A manual of the practice of medicine / by George Hilaro Barlow. Source: Wellcome Collection.

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    receiving the infection of this disease, either from its genera] prevalence at the time, or from the possibility of its being con- veyed, as in hospitals, by nurses or other attendants. Scarification is chiefly employed in superficial inflammation, as of the integuments or areolar tissue immediately underneath them, and has the advantage of directly unloading the smaller vessels. (1.) The effects of general bleeding are commonly stated to be—1, a diminution of the force and frequency of the heart's action; 2, a derivation of the blood from the inflamed part; 3, a modification of the character of the blood itself. The blood is the natural stimulus of the heart, by which the contraction of its cavities is excited and maintained; and although the heart of some animals will continue to act for a time, even after removal from the body, yet the effect of loss of blood upon persons in health, as well as that of obstruction to the supply of blood to the left ventricle in disease, shows that the consequence of a withdrawal of this stimulus is a diminu- tion in the force and frequency of the heart's action. At the same time it may be observed that this depression is not entirely owing to the direct effect of the withdrawal of its accustomed stimulus from the heart, but also to the rapid removal of the pressure upon the brain and medulla oblongata ■ though the effect of this latter has, as we have already seen in speaking of syncope, been considerably over-estimated. Still it is an important fact that when blood is drawn in the erect Posture, so that the influence of gravitation co-operates with tnat ot the operation iii weakening the flow of blood to the neacl, not only are the sensations and consciousness of the patient, i. e., the functions of the brain and medulla oblongata, much sooner affected; but the heart's own action is much •sooner impaired than when the same quantity is taken from a patient lying horizontally : a most remarkable diminution of W ™?UTi,- tJie Pulsations is thus very frequently effected, puke falling for example, from 120 to GO in a minute, at nrnrW™?..tSneJiat ftutltness and transient insensibility are produced. * We perceive then that the depressing agency of poterfuTbutttld,Ti!he r rore and atfi^ 2£ power ul, but on the other hand more transient, acting through • .nd medulla oblongata, and producing an effect We mat oi sudden concussion or shock,-the other more gradual i 'ln1': Patent, ariring from the abstraction of the Si Sons even 1 T* *™ n?ode8 of action- that some E ,^hen labouring under inflammation of an active cll^acter, will, ,( bled m a full stream, and in an erect position! • Alison's ' Outlines of Pathology and Practice,' p. 217.
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