THE THORACIC AND ABDOMINAL WALLS 153 



Paracentesis Thoracis (Tapping the Chest). 



The accumulation of fluid in the chest can usually be 

 traced as a sequel to an attack of pleurisy, although in many 

 cases no acute symptoms of the disease have been observed 

 by the owner. It is equally commonly met with in the dog 

 and cat. 



Symptoms. — The patient is noticed to be dull, capricious in 

 appetite, and to have lately become very much emaciated ; 

 exercise or other exertion causes distress and great lassitude, 

 the respiration being distinctly laboured, and a line from the 

 last rib diagonally along the tucked-up flank (the so-called 

 ' pleuritic ridge ') is well seen in short-haired dogs. The 

 temperature is not usually high, and may even be normal or 

 sub-normal. 



Occasionally the appetite will remain ravenous even until a 

 very late stage in the disease, and death may occur suddenly 

 without any. preliminary warning. The operation of ex- 

 ploring the chest is done to verif}' the diagnosis of fluid, and 

 effect its removal when found to be present. 



Operation. — Unless absolutely necessary, it is not advisable 

 to fix the patient before performing this operation, but merely 

 to have the animal quietly held in the standing position. 

 Any pressure on the throat or chest is dangerous, and death 

 is very apt to ensue suddenly from asphyxia if the patient 

 struggles or falls heavily to the ground. Carefully shave the 

 hair from and disinfect (see p. 2) a spot about an inch above 

 and behind the point of the elbow on the right side ; a fine 

 trocar and cannula, which have been boiled, are introduced 

 subcutaneously for a short distance, and the point turned in 

 between two of the ribs (usually the sixth and seventh or 

 seventh and eighth ; see Fig. 122). The trocar is then with- 

 drawn and the cannula inserted as far as necessary, the fluid 

 contents of the chest being allowed to escape slowly. Any 

 material blocking the end of the cannula and retarding the 



