INHALATION 375 



result from asphyxia, depending upon some fault in its 

 administration. As Sir Lauder Brunton has aptly observed, 

 suffocation and anaesthesia are a deadly combination. 

 There is one effect of chloroform, not recognised by the 

 Commission, which may be dangerous and even cause 

 death. If concentrated vapour is given early during the 

 administration the vagus centre in the medulla is so stimu- 

 lated and excited that inhibition of the heart may result. 

 That such is the cause is proved by the fact that it cannot 

 be produced if the vagi are cut, and further, a dose of atro- 

 pine given beforehand paralyses the vagus endings in the 

 heart, and so prevents any inhibition. Schafer has sug- 

 gested the use of atropine as a routine measure in chloro- 

 form administration, but the better method is to give the 

 drug slowly. Dangerous restriction of air may result from 

 the inhaling apparatus unduly closing the nostrils. Ingress 

 of air may be arrested by pressure on the neck or chest, 

 by the animal being placed in an awkward position, by the 

 tongue dropping on to the larynx, or by vomited food 

 entering the windpipe. In forcibly restraining the early 

 struggling, breathing is sometimes interfered with, and the 

 deep inspirations which usually subsequently occur will 

 convey into the lungs and distribute to the nerve centres 

 unduly large quantities of the anaesthetic vapour. The 

 experienced practitioner is always specially watchful of 

 cases in which there is much struggling ; he pushes the 

 administration as rapidly as is safe, in order quickly to 

 produce perfect anaesthesia,' but so soon as this is effected 

 he allows several full draughts of air. At this stage the 

 napkin, nose-bag, or inhaler may be removed, for so soon 

 as full anaesthesia is produced, the insensibility is readily 

 maintained by small quantities of the drug, given occa- 

 sionally. 



The further precautions mainly consist in the chloro- 

 formist bestowing undivided attention on two points : (1) 

 He must watch the breathing, in order that the patient's 

 safety shall be maintained by fresh air entering the lungs, 

 thus preventing any dangerous accumulation of the drug, 

 and the arrest of natural respiration ; (2) he must maintain 

 throughout the operation the requisite degree of anaes- 



