The Abdomen 147 



reeled towards keeping up the heart's action, and encouraging the 

 ehmination of morbid matter through the excretory organs. 



ASCITES. 



This is a trouble of purely mechanical nature, the result of im- 

 paired circulation. It must be remembered that there are two cir- 

 culatory systems in connection with the abdominal cavity — the sys- 

 temic and the portal, and that anjrthing which arrests the circulation 

 in either of these is liable to lead to ascites. The most frequent cause 

 would seem to be cardiac lesions, producing altered relationship be- 

 tween arterial and venous blood pressure and blood flow. There 

 then follow venous stagnation, capillary starvation and distension, 

 and transudation of certain of the fluid constituents of the blood. 

 Cadiot witnessed thirty-seven cases in less than three years and based 

 thereon statistics of the relative frequency of occurrence of the 

 various causes of the disease. Of twenty-eight cases, ten of the ani- 

 mals were afflicted with cardiac disease (pericarditis-7, mitral 

 lesions-2, tricuspid lesions-i). The next most frequent factor was 

 tuberculosis of the liver, omentum, or mesentery, eight of the ani- 

 mals being thus affected. Pleuritis was responsible for four of the 

 cases, malignant tumor of the liver and lungs two, hepatic 

 cirrhosis without cardiac lesion three, and carcinoma of the 

 liver one. Of the remainder of the animals, five suffered 

 primary ascites proceeding from chronic peritonitis, and in six which 

 were seen but once, the causative disease was not definitely diag- 

 nosed. Chronic renal diseases and compression or obliteration of 

 the portal vein by neoplasms may also cause ascites. 



The amount of accumulated fluid in ascites may be very con- 

 siderable, sometimes amounting almost to the actual body-weight 

 of the animal. Hobday removed five and one-half gallons from a 

 Mastiff by canula. It may be clear or yellowish and opalescent, 

 and sometimes contains white and red cells and endothelium. It 

 rarely coagulates. It is often of a pinkish tint when malignant 

 neoplasm is the causative factor, owing to rupture of vessels on the 

 surface of the tumor. A remarkable condition known as chylous 

 ascites may result from traumatic rupture of a lymphatic trunk 

 whereby the cavity becomes filled with a thick opalescent or milky 

 fluid rich in proteids and fine fatty globules with a tendency to 

 coagulate. 



