PNEUMOTHORAX. 135 



Dropsy of the Chest. 

 {Hydrothorax.) 



Any accumulatioa of serous fluid that is not dependent on an 

 inflammation of the pleura (that is, of a transudate) in the cavity 

 of the thorax is called hydrothorax. This is often a symptom of 

 general dropsy, or it may arise from chronic disease of any of the 

 organs (see ascites). In such cases the effusion first shows itself 

 in the chest when dropsy of the skin (anasarca) exists. 



Pathological, Anatomy. Hydrothorax, as a rule, affects 

 both sides of the chest. Frohner records a case where one side 

 only was affected. We find in the cavity of the chest a clear 

 yellow fluid, sometimes mixed with blood; the pleura is cedematous, 

 swollen, and in loBg-continued cases it has a flaccid or macerated 

 look. The lungs do not present any change, except the signs of 

 partial compression. The other organs of the body are ansemic. 



Clinical Symptoms. The physical examination of this dis- 

 ease presents symptoms very similar to pleuritic exudates, but in 

 dropsical transudates both sides of the thoracic cavity are filled, 

 and on changing the position of the animal the fluid moves about 

 much more quickly than a pleuritic exudate would, and the sensi- 

 tiveness of the animal to pressure on the walls of the chest and 

 the rubbing or crepitating bruit of pleuritis are absent. 



Therapeutics. The treatment, as a rule, is of a palliative 

 character, as it is only in very rare instances we succeed in remov- 

 ing the original disease; we use the same agents as in ascites. The 

 operation of tapping the chest-wall (see Puncture of the Cavity of 

 the Chest, page 134) is only to be resorted to when the fluid has 

 collected in large quantities and the animal is threatened with 

 suffocation; but this only affords temporary relief. 



Pneumothorax. 



Etiology. The cause of jjneumothorax — that is to say, the 

 accumulation of air in the thorax — is produced in several ways. 

 By perforating wounds of the chest, by the breaking into the 

 pleural cavity of a collection of pus from the lung, tearing of the 

 lung-tissue from great exertion, and from perforation of the 

 oesophagus. 



