On the physical exploration of the lungs / by George W. Balfour.

  • Balfour, George William, 1823-1903.
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: On the physical exploration of the lungs / by George W. Balfour. Source: Wellcome Collection.

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    the body giving forth the sonorous vibrations with its own funda¬ mental note, and in percussion it therefore varies infinitely with the nature of the body thrown into sonorous vibrations. It is there¬ fore of importance in percussing the chest to avoid, as far as possible, all sources of confusion which may be traced to clang. For this reason I have already mentioned the care which ought to be exer¬ cised in selecting a suitable plessor and pleximeter; for this reason also we must carefully avoid indiscriminately comparing the percus¬ sion note of a rib with that of an interspace; but must always com¬ pare rib with rib, and interspace with interspace. Over the sternum, clang often simulates increased resonance by a lowering of the pitch ; over the shoulder-blades, clang simulates diminished resonance by a heightening of the pitch. We must therefore percuss the sternum by itself, and avoid comparing its percussion note with that of either the ribs or interspaces on either side ; and for a similar reason we must, in percussing the scapular regions, compare the right scapular region with the left one, and not with any part of the chest above or below it. A mass of fluid or of perfectly airless flesh, when percussed under conditions which are such as completely to obviate any communi¬ cation of the percussional vibrations to sonorous bodies lying above or beneath them, is incapable of being thrown into sonorous vibra¬ tions, is therefore perfectly free from clang, and gives forth on percus¬ sion absolutely no sound at all. Out of the body, the nearest approach to this absolute freedom from all sound is obtained when we percuss a mass of solid flesh, six inches at least in thickness, or a perfectly full jar of any fluid, over one inch in diameter, and at least six inches in height, both placed upon a solid stone table of some inches in thickness. Upon these masses the pleximeter must be closely applied, and the only sound then produced by percussion is simply the unavoidable clang of the pleximeter when struck by the plessor. Within the body, it is obvious that similar conditions are unattainable. The percussional vibrations are always more or less communicated to the ribs or air-containing organs—the lungs, stomach, or intestines—in the neighbourhood of the part percussed ; and we have their clang always mingling with that of the plexi¬ meter, so that the absence of sound in percussing organs within the body is never so complete as in the conditions described. In the healthy body, the nearest approach to this entire absence of sound on percussion is obtained on the left side in the fourth interspace, about an inch and a half from the left edge of the sternum ; and on the right side, in the fifth interspace, anywhere to the right of the