34 



CANINE AND FELINE SURGERY. 



before proceeding. The second stage is one of excitement 

 during which the animal is in a semi-conscious state, and 

 appears in an ahnost frenzied condition, yelping and struggling 

 violently, and often involuntarily relaxing the sphincters of the 

 rectum and bladder. After this we get the third or safe ana;s- 

 thetic stage, in which the animal is ready for the operation ; 

 and lastly, the fourth or dangerous stage, in which there is risk 

 of permanently paralysing one or more of the great vital centres. 

 When the anjesthetic is administered very gradually it is often 

 possible to cause the animal to pass into the third stage without 



Fig. 17. 

 Diagram of author's third pattern of inhaler showing another form of mask. 



becoming in any way frenzied or excited ; one can frequently 

 succeed in quietly anaesthetising small dogs whilst they are held 

 in the arms of the owner without being secured in any way 

 and without any struggling, the animal passing tranquill}' into 

 the stage of unconsciousness. 



The first signs of the approach of the stage of safe anaesthesia 

 are that the struggling becomes less, the efforts being weaker, 

 and the tail becomes limp ; then the hind quarters become 

 powerless, and ultimately the head cannot be raised. When 

 the whole body is totally limp and respirations are regular the 



