458 DISEASES OF THE CIBOULATORY SYSTEM. 



culty of the respiration. The course of pericarditis is sometimes 

 acute, at other times chronic; in the acute form, death may happen 

 suddenly through heart rupture. In the dog, the symptoms of 

 hydro-pericardium are the following: intense dyspnœa, cyanosis, 

 swelling of the jugular veins, imperceptible cardiac impulse, which 

 is undulatory or chopping ; the pulse is rapid and irregular ; we 

 also see dropsies, emaciation, and marasmus. 



Differential diagnosis. Pericarditis may be confounded with 

 endocarditis and pleurisy, but it is easy to distinguish it from pul- 

 monary affections. The differential diagnosis of pericarditis and 

 endocarditis must be based upon the very special characters of the 

 bruits localized in the pericardium ; these are friction bruits which 

 the observer thinks he hears immediately below the ear; they are 

 sometimes felt, and they are not so closely related to both phases of 

 the cardiac rhythm as the endocarditic bruits ; besides, the heart- 

 sounds are absolutely normal and without intimate connection with 

 the pericarditic bruits. It is more difficult to distinguish it from 

 pleurisy at the beginning ; this latter trouble is also accompanied 

 by a bruit of friction, which, however, is rather isochronous with 

 the respiratory movements than with those of the heart, and besides 

 the circulatory troubles are wanting. Sometimes pericarditis is 

 secondary and is related to the pleural inflammation. In doubtful 

 cases we must conclude the existence of pleurisy (Roll), which is rela- 

 tively much more frequent than inflammation of the pericardium. 



Treatment. In the horse and dog pericarditis is much less 

 serious than in the ox, and its treatment offers many more chances 

 of success. It consists in avoiding excitements, fatigue, and in the 

 use of refrigerants and antiphlogistics : applications of ice or per- 

 manent irrigation of cold water ; this latter method is the most ad- 

 vantageous for the horse. Internally we give digitalis (for the horse, 

 10 to 12 grammes per day ; for the dog, 0.1 to 0.3 gramme) ; we 

 may also use tartar emetic and salts. If the trouble shows a chronic 

 course we must resort to the drastics and diuretics. When the 

 quantity of exudate becomes threatening to life, or if it remains 

 stationary, we may puncture the pericardium by means of the 

 trocar. In the horse we practise the puncture in front of the ante- 

 rior edge of the fifth and sixth ribs, a handbreadth above the floor 

 of the pectoral cavity ; it is proper to make a preliminary incision 

 of the shape of a buttonhole into the skin in order to facilitate the 

 introduction of the instrument. In subjects of our small species, 



