Notes on the pneumothorax occurring in phthisis / by R. Douglas Powell.

  • Powell, Richard Douglas, 1842-1925.
Date:
1869
Catalogue details

Licence: Public Domain Mark

Credit: Notes on the pneumothorax occurring in phthisis / by R. Douglas Powell. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    displaced towards the opposite side by the pressure of the escaped air is not wholly true, for the displacement is instantaneous. This was first noticed as a clinical fact by the writer in 1865, in a case seen within two or three min- utes of seizure; the explanation was not then, however, apparent. The true mode of production seems to be the following :—The mediastinum (including the heart) is the only boundary common to the two thoracic cavities, which is flaccid, and admits of a certain degree of passive move- ment to either side. It is maintained in position (and with it the heart) by the opposing elastic tensions (a) of the two lungs, each tending to draw it (the mediastinum) to its own side. Now, if the elastic tension of one lung be destroyed by the admission of air from without into the pleural cavity, causing the lung to collapse, the elasticity of the other lung has no opposing force, and immediately draws the mediastinum, and with it the heart, to its own side. More- over, when an inspiratory effort is made, it is impossible for the elasticity of the sound lung to be overcome, and, consequently, for its expansion to commence, until the me- diastinum has become sufficiently convex to be stretched, and thus to form a resisting wall. In this way and to this extent the displacement of the heart is immediately and necessarily consequent upon the admission of air into the pleura. Beyond this it may be increased by the direct pressure produced by the subsequent accumulation of air. (a) This tension was found by Dr. Salter, in some experiments on the dog, to be equal to from twelve to eighteen inches of water. Lecture at the College of Physicians, 1805.)