38 CANINE AND FELINE SURGERY. 



istered before respiration actually ceases. If this could always 

 be done the proportion of deaths during antesthetisation in the 

 dog and cat would be infinitesimal. 



Since chloroform is an agent which destroys life by paralysing 

 either the respiratory or cardiac centres, and sometimes both 

 apparently at once, the objects sought for in an antidote are 

 those which will act as a stimulant and restorative to either or 

 both. It is important then that the anaesthetist shall select the 

 one which seems most nearly to fulfil these objects. 



In ammonia vapour, such as is evolved from liq. ammon. fort, 

 we have an agent whose therapeutic actions are those of general 

 stimulant, both respiratory and cardiac, but we dare not give 

 it in the form of a draught, because the patient is unable to 

 swallow, and we cannot inject it hypodermically on account of 

 its slowness of absorption and irritant action, whilst its intra- 

 venous injection is difficult, so that it is usually given in the 

 form of a vapour inhalation. It is needless to remark that the 

 respiratory apparatus must be artificially induced to work if it 

 has ceased to do so, in order that the effect of the vapour may 

 be shown on the body. This is sometimes a source of difficulty, 

 and when once the respiratory organs have recommenced to 

 work the vapour must not be too suddenly applied, or the 

 reaction is apt to be too severe. It must be used at intervals 

 with discretion, holding the bottle under the patient's nostrils 

 for a few moments and then withdrawing it. 



With amyl nitrite the chief action is that of a cardiac stimu- 

 lant, and it has the advantages of being non-irritant and readily 

 absorbed from mucous surfaces, so that it can be administered 

 on the tongue. The necessary dose, too, is very small, and it 

 can be given undiluted. For the dog or cat about one quarter 

 of a minim for each pound body-weight is a fair average dose. 



Hydrocyanic acid ^ first suggested itself as an antidote to 

 chloroform whilst watching the powerful respiratory efforts 



1 "Journal of Comparative Pathology and Therapeutics," Vol. XI., p. 101. "Lancet," 

 1st Jan. 1898. 



