243 



wear suspensory bags when they are exercised. Piles may often be re- 

 duced by astringeut washes — tea made from white oak bark or a satu- 

 rated solution of alum. Tlie bowels should be kept loose with bran 

 mashes and the animal kept quiet in the stable. When varicose veins 

 exist superficially and threaten to produce inconvenience, they may be 

 ligated above and below and thus obliterated. Sometimes absorption 

 may be induced by constant bandages. 



AIR IN VEINS— AIR EMBOLISM. 



It was formerly supposed that the entrance of air into a vein at the 

 time of the infliction of a wound or in blood-letting was extremely dan- 

 gerous and very often produced sudden death by interfering with the 

 circulation of the blood through the heart and lungs. Danger from air 

 embolism is exceedingly doubtful, unless great quantities were forced 

 into a large vein by artificial means. 



PURPURA HEMORRHAGICA. 



Purpura hemorrhagica usually occurs as a sequel to debilitating dis- 

 eases, such as strangles, influenza, etc. It may, however, arise in the 

 absence of any previous disease in badly ventilated stables, among 

 poorly-fed horses, and in animals subject to exhausting work and ex- 

 treme temperatures. It is apparently due to a primary deterioration of 

 the blood, weakness of the capillary vessels, and general debility or ex- 

 haustion of the nervous system. Its gravity does not depend so much 

 upon the amount of blood extravasated as it does upon the disturbance 

 or diminished action of the vasomotor centers. 



t>\jmptoms. — This disease becomes manifested by the occurrence of 

 sudden swellings on various parts of the body, on the head or lips, limbs, 

 abdomen, etc. They may be diffused or very markedly circumscribed, 

 though in the advanced stages they cover large areas. They pit on 

 pressure and are but slightly painful to the touch. The limbs may 

 swell to a very large size, the nostrils may become almost closed, and 

 the head and throat may swell to the point of suffocation. The swell- 

 ings not infrequently disappear from one portion of the body and de- 

 velop on another, or may recede from the surface and invade the intes- 

 tinal mucous membrane. The mucous lining of the nostrils and mouth 

 is covered with dark red or purple spots, a bloody colored serum flows 

 from the nostrils, the tongue may be swollen and prevent eating or 

 closing of the jaws. In twenty-four or forty-eight hours bloody serum 

 may exude through the skin over the swollen parts, and finally large 

 gangrenous sloughs may form. Tlie temperature is never very high, 

 the pulse is frequent and compressible, and becomes feebler as the ani- 

 mal loses strength. A cough is usually present. The urine is scanty 

 and high colored, and when the intestines are much affected a bloody 

 diarrhea may set in, with colicky pains. Some of the internal organs 



