A manual of the practice of medicine / by George Hilaro Barlow.
- George Hilaro Barlow
- Date:
- 1861
Licence: Public Domain Mark
Credit: A manual of the practice of medicine / by George Hilaro Barlow. Source: Wellcome Collection.
Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.
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![felt by tlie finger u]ion tlie radial artery, and the pulse will l)e hard or very full, but generally the foi-mer, according as tlie resistance of the coats of the artery is increased or diminished. The ventricle may, however, upon the other haiid, be thin, or weak, from degeneration, and in this case, the pulse will be feeble and small, from the scanty jet thrown into the artery at each systole; and, as a necessary consequence,the ventricle not wholly emptying itself, it will be continually excited to contract, by the constant presence of blood in its cavity, and therefore the number will be increased, or, in other words, the pulse will be rajjid as well as small and feeble. A very feeble state of the ventricular parietes may also, by causing delay in the circulation, give rise to irregular or intermittent pulse, in the manner to be presently noticed. Again, as a mechanical condition, the mitral valve may be imperfect, in which case, the blood regui'gitating into the auricle, the quantity thrown into the aorta must be diminished, and the pulse will be small; or owing to the left ventricle not receiving a regular supply of its natural stimulus, tlie blood, its contractions, and consequently the pulse, will be irregular. It may here be well to observe that independently of lesions of innervation, the chief, if not the only cause of intermittent pulse is a want of a due supply of blood to the left ventricle : this may happen in two ways—either the current flow ing into it may be considerably diminished, as in the case of a narrowed mitral orifice ; or the cavity of the ventricle may have become enlarged by dilatation, and the quantity of blood required to excite regular contraction increased ; in which case any obstruction tergal to the ventricle, or dimirmtion in the activity of the circulation, will induce intermission. (2.) Passing from the left ventricle to the orifice of the aorta we observe, that if this orifice be narrowed, the jet into the aorta must be diminished, and therefore the pulse small in comparison with tlie impulse of the heart. If, on the other hand, the valves of the aorta be imperfect, we may have a suffi- cient quantity of blood thrown into that vessel with each contraction of the ventricle ; but, a portion of it regurgitating by the elasticity of the artery, the current of the blood will not be continuous, and therefore, although the pulse may at first be felt sharp and full, it immediately subsides, conveying to the finger, the impression of a splash, with a recoil, ratlier than of an undulating current passing underneath it; this is what has been termed the splashing or water-hammer' pulse. There is another character of pulse whicli is sometimes imparted to it by disease about the aortic orifice, namely, the thrill. This may be felt when the current has been split or disturbed by anything projecting into it or drawn across it, or when there is a warty excrescence upon one of the semilunar](https://iiif.wellcomecollection.org/image/b21509104_0082.jp2/full/800%2C/0/default.jpg)
