A treatise on the diseases of the chest and on mediate auscultation / by R.T.H. Laennec.

  • Laennec, R. T. H. (René Théophile Hyacinthe), 1781-1826.
Date:
1827
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the diseases of the chest and on mediate auscultation / by R.T.H. Laennec. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    more particularly In those points wh^rc the lungs, in their di- latation, approach nearest to the thoracic parietes, for instance, the anterior-superior, the lateral, and the posterior-inferior regions. Ilie hollow of the axilla, and the space between the clavicle and superior edge of the trapezius muscle, exhibit the phenomenon in its greatest intensity. To judge correctly of the state of respiration by this me- thod, we must not rely on the results of the first moments of examination. The sort of buzzing sensation often caused by the first application of the instrument, the fear, restraint, and agitation of the patient, which mechanically lessen the force of respiration, the frequently inconvenient posture of the ob- server, and the great sensation occasionally produced by the action of the heart,—are all causes which may at first prevent us from correctly appreciating, or even from hearing at all, the sound of inspiration and expiration. We must, therefore, al- low some seconds to pass before we attempt to form an opi- nion. I need hardly observe that there miist be no noise whatever in the vicinity of the patient. I have already mentioned the necessity of the observer avoid- ing uneasy postures. Besides the inconveniences stated, this may also mislead by occasioning the auscultator to hear the sound of the contraction of his own muscles. We must be equally on our guard that the patient does not excite this sound In his own muscles, by too strong a contraction of them in crossing the arms, leaning forward or resting on the el- bow. On this account, in the examination of weak subjects, it is always better to have them supported by assistants, than to make them exhaust their remaining strength in keeping themselves in the erect position. It is right to observe, how- ever, that all these precautions are only necessary to beginners. After one or two months' experience, the ear becomes accus- tomed to the sound it is In search of, and Is able to discrimi- nate it from all the others with which it may be combined, even when weaker than they are. The intervention of clothing, even when of considerable thickness, does not sensibly diminish tlie sound of respiration; but we must be careful that there is no friction between this and the instrument, as this circumstance, especially if the clothes arc of silk, or of a fine hard stuflfj. may mislead us by exciting a sensation analogous lo that produced by respiration.