ANESTHESIA. 41 



III. ANAESTHESIA. 



Anesthesia may be divided according to its nature and extent 

 into general and local. We shall consider these in order. 



The first operation under ether was performed on the 14th October, 

 1846, by Warren, in the Faculty of Medicine at Boston. Boots and 

 Lister first employed ether in England. During 1847 several 

 veterinary surgeons published experiments showing the advantages 

 of its use in operations on the horse. 



Notwithstanding certain drawbacks ether was at first exclusively 

 used, but on the 10th November, 1847, Simpson drew attention to 

 the anaesthetic qualities of chloroform, which he declared superior 

 to its predecessor. Chloroform soon displaced ether, maintaining 

 its supremacy in man until a relatively recent date. In animals, 

 save perhaps the dog and cat, it is still the most popular anaesthetic. 



Other substances have since been introduced. The first departure 

 was probably the mixture of ether and chloroform, with or without 

 alcohol. The rectal administration of ether was then suggested, 

 followed by the use of morphine, the intra-venous, intra-rectal, or 

 intra-peritoneal injection of chloral, the inhalation of chloroform in 

 conjunction with subcutaneous injections of morphine and atropine, 

 and the administration of paraldehyde, urethane, and methylene. 

 When, as in oxen, the flesh would be used for human food in case 

 of the operation failing, large doses of alcohol are often given. 



In general anaesthesia the patient is thrown into a more or less 

 profound artificial sleep. It is not always necessary, however, to 

 act on the entire individual. Sometimes the operation only affects 

 a very limited area, and local anaesthesia suffices. Local anaesthesia 

 may be produced by the application of ice or freezing mixtures, by 

 the spraying of certain liquids, like ether or ethyl chloride, or by the 

 subcutaneous injection of a solution of cocaine, eucaine, stovaine, 

 or novocaine. 



Anaesthetics are quite as useful in animals as in man ; and few 

 important operations are performed on veterinary patients without 

 anaesthesia, either local or general. For most minor operations, the 

 means of control at our disposal are sufficient without general 

 anaesthetics, but certain operations cannot be well performed without 

 them. In reduction of hernia?, delivery in cases of dystokia, in 

 laparotomy, and all cases where one works in dangerous proximity to 

 important organs, the animal's struggles render general anaesthesia 

 almost indispensable. It is also necessary for delicate operations on or 



