PREVENTION, SYMPTOMS AND TREATMENT 



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early stages of severe inflammatory attacks of the brain or its mem- 

 branes. 



In cerebral congestion, and dyspnea due-to gastric tympany and 

 pressure on the diaphragm, bleeding may give relief. Blood-letting 

 is particularly applicable in the prophylactic treatment of parturient 

 apoplexy of cows, when the disease has once occurred, and may 

 be practised in plethoric animals immediately before parturition. 

 Venesection alleviates dangerous pulmonary congestion, removes 

 the venous load on the right heart, and relieves dyspnea and cya- 

 nosis by making it possible for the heart to force a smaller quantity 

 of blood through the less obstructed lungs. 



A feeble and easily compressible pulse does not necessarily con- 

 traindicate venesection in engorgement of the lungs, for this condi- 

 tion leads to stasis in the pulmonary circulation, prevents the proper 

 flow of blood into the left ventricle, and thus causes arterial anemia. 

 Therefore, so far from contraindicating blood-letting, this condi- 

 tion urgently demands it. Alarming dyspnea, great cyanosis, to- 

 gether with a general plethoric state, should guide us in blood-letting 

 in sthenic pneumonia and pulmonary congestion, rather than the 

 state of the pulse. Venesection is serviceable in advanced cases of 

 cardiac disease in dogs — with failing compensation, venous engorge- 

 ment of the lungs, and dyspnea — by relieving obstruction to the 

 right heart. Moderate blood-letting is occasionally useful in severe 

 cases of acute pleuritis, laminitis, lymphangitis and urticaria in 

 plethoric horses. 



Finally, in various toxemias, blood-letting drains away both 

 the blood and its contained poison. The mass of blood removed may 

 be advantageously replaced by injection of normal salt solution into 

 a vein or under the skin. This method is not in prevalent use in 

 veterinary medicine, but is applied with notable success in human 

 practice. Every veterinary practitioner should be competent to 

 bleed an animal. An amount greater than 1/5 of the total quantity 

 of blood should not be withdrawn. The total quantity of blood is 



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