On the art of percussion : as applied to the diagnosis of thoracic and abdominal diseases / by John Hughes Bennett.

  • Bennett, John Hughes, 1812-1875.
Date:
[1842]
Catalogue details

Licence: Public Domain Mark

Credit: On the art of percussion : as applied to the diagnosis of thoracic and abdominal diseases / by John Hughes Bennett. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    comprehension of the sounds which may be cHcitcd in a morbid state. Thus, the lungs may occasion a dull or parenchymatous sound, from solidification, the result of pneumonia or tubercular deposition, or on the other hand, become more tympanitic, from the presence of emphysema. The abdomen may give out a paren- chymatous sound, from enlargement of the uterus, or an ovarian tumour; or a himioral sound, from the effusion of fluid in the cavity of the peritoneum. Of the Sense of Besistance produced hy Percussion.—By the sense of resistance, is understood the peculiar sensation resulting from those impressions which are communicated to the fingers on strik- ing hard, soft, or elastic bodies. It is of the greatest service in determining the physical condition of the organ percussed. The sense of resistance bears relation to the density of the object struck,—hence firm and solid textures offer more resistance than those which are soft or elastic. Of all the thoracic and abdo- dominal organs, the liver presents the greatest degree of resis- tance, and the stomach the least. The presence of fluid in the hollow viscera, offers a medium of resistance between the paren- chymatous organs on the one hand, and those containing air on the other. But air much condensed, or fluid Contained within the rigid walls of the thorax, may offer a considerable degree of resistance. The sense of resistance should be as much educated by the physician as the sense of hearing, and it would be difficult for an individual, practised in the art of percussion, to say which of these two points is most valuable to him. Both are only to be learnt by practice, and considering it perfectly useless to de- scribe that in words which may be learnt in half an hour, by the use of the pleximeter and hammer on a dead body, or the living subject, I shall now proceed to describe the General rules to he folloioed in the practice of Mediate Percussion.— 1. The pleximeter should be held by the projecting handles be- tween the thumb and index finger of the left hand, and pressed firmly down upon the organ to be percussed. Much depends upon this inile being followed, as the sound and sense of resis- tance are considerably modified according to the pressure made by the pleximeter. A very easy experiment will prove this. If, for instance, the pleximeter be struck while it rests lightly on the abdomen over the umbilicus, and again, when it is pressed firmly down amongst the viscera, the change in tone will be at once perceived. In the first case a dull sound is produced, from the muscles and integuments being alone inHuenced by the force of the blow; in the second case, a clear tympanitic sound is occasion- ed from the vibration of the walls of the intestine. In every in- stance, therefore, thepleximetershouldbe so held and ])rosseddown, as to render it, so to speak, a part of the organ we wish to percusp.