DISEASES OF THE RESPIRATORY SYSTEM. 153 



is better than a fatal termination. It is better not to blemish, if 

 possible. 



Tapping the chest (paracentesis thoracis) is occasionally used, 

 but with unsatisfactory results. About the eighth or ninth inter- 

 costal space, midway between the level of the sternum and the level 

 of the fluid is the point to introduce the trocar and canula, or, bet- 

 ter, an aspirator. 



The diet and means of keeping up the appetite are very impor- 

 tant. 



Coax the animal to eat; give him gruel, grass, apples, and the 

 like if he will not eat bran or steamed oats. 



EMPYEMA. 



Give the synonym. 



Purulent pleurisy. 



What is empyaema ? 



This is pus in the pleural cavity. 



Although quite common in man, it is more or less rare in 

 animals. It may occur from injuries to the chest cavity involving 

 the pleura. 



HYDKOTHOEAX. 



What is understood by hydrothorax? 



This may be defined to be water or serum in the pleural cavity. 



It is somewhat rare in equines, it being more frequent in the 

 sheep and the dog; it is a non-febrile disease, with about the same 

 physical signs as in the second stage of pleurisy. 



Dyspnoea is the principal s}Tiiptom. 



What is the treatment ? 



Build up the system. Give diuretics, diaphoretics, and absorb- 

 ents. Stimulants may be indicated. 

 Locally, blisters may be beneficial. 



PNEUMOTHORAX. 



Give the definition and causes of pneumothorax. 



It is an accumulation of air in the pleural cavity, due, usually, 

 to penetrating wound — broken rib or abscess breaking internally 

 and externally. 



