536 TLEURISY. 



serous fluid. Here, after a longer period of convalescence, we 

 may calculate upon a removal of a certain amount of the fluid 

 exudate ; Ave cannot, however, with anything like the same 

 confidence, calculate upon the removal of the organizations, the 

 false membranes and adhesions. These may, and often do, 

 continue for life, and may prove obnoxious in future attacks of 

 inflammatory action. 



When this almost invariable condition or sequel of inflam- 

 mation of the pleura is of such an extent as seriously to inter- 

 fere with the pulmonic function, and when unrelieved by ab- 

 sorption, we speak of the condition as dropsy of the chest, or 

 Hydrotlwrax. When the morbid pleuritic action is from the 

 first very intense, or from some peculiar specificity in connec- 

 tion with the action itself, or the influences brought to bear 

 upon the animal, we have in association with the etiused Uquid 

 a quantity of pus sufficient to give it a true purulent appear- 

 ance, the condition is termed Eiivpycema. 



Diagnosis of Pleurisy. — Pleurisy may be distinguished from 

 pneumonia and bronchitis by the evidence during the earher 

 stages of its invasion of a greater amount of pain and fever, 

 by the harder and more incompressible nature of the pulse, 

 the shorter and more painful cough. The respirations, which 

 are simply accelerated in pneumonia, are never, unless com- 

 plicated with the membranous inflammation, of the purely 

 abdominal character we observe in pleurisy. In pleurisy we 

 want the crepitant rale found existing in pneumonia ; while 

 when absence of sound is indicated by auscultation, we find 

 that in the pleuritic affection it is the result of the presence 

 of fluid in the pleural cavity, while in the pulmonic it usually 

 arises from consolidation of lung-tissue. 



When occurring from solidification of lung-tissue, the 

 absence of sound is not equally distributed, the respiratory 

 noise being most marked farthest from the solidified portions, 

 gradually becoming less distinct as the more perfectly oblite- 

 rated air-cells are reached. When the deficiency or modi- 

 fication of sound is due to the presence of fluid in the chest, 

 the absence or modification takes place, abruptly or at once, 

 at a certain height from the floor of the thorax, indicative of 

 the height to which the fluid has extended. 



In cases of extensive inflammati(in of the pleural membrane 



