6o OPERATIVE TECHNIQUE. 



seven and a half grains, per pound of body-weight. Roucher has 

 sHghtly modified this method. The bowel is cleared with a soap and 

 water or glycerine enema, and a subcutaneous injection of morphine in 

 the proportion of Jrrth grain of hydrochloride of morphine per lb. 

 of body-weight administered, followed by an enema of one drachm ot 

 chloral hydrate in linseed emulsion. If necessary the dose may be 

 repeated in seven to eight minutes ; very large dogs may require a 

 third, or even a fourth. The disadvantages are the same as in the 

 horse. Anaesthesia is slow and haemorrhage abundant. 



Richet has recommended intra-peritoneal injections of chloral 

 alone or associated with morphine. Injected into the peritoneum 

 chloral produces complete anaesthesia in about ten minutes. The 

 injection is made with a Pravaz's syringe, the greatest care being 

 taken in regard to asepsis. When well diluted, chloral is tolerated 

 by the peritoneum. Morphine added to the chloral prolongs anaes- 

 thesia to about one hour without danger of syncope. In this 

 method the doses are, hydrochloride of morphine "02 grain, chloral 

 four grains, per pound of weight. The method, however, does not 

 seem to have proved permanently successful, dangerous complications 

 sometimes occurring. 



Frohner regards urethane as one of the best agents for the dog, and 

 has tried hypnone and paraldehyde with good results. Desoubry gives 

 from 22 to 30 grains of sulphonal to dogs of 40 lbs. body-weight, and 

 highly praises the method. 



In the dog and cat, however, the best method probably consists 

 in using chloroform after a preliminary injection of atropine and 

 morphine. The morphine modifies excitement at the commencement 

 of anaesthesia ; the atropine prevents cardiac syncope by suspending 

 the function of the cardiac moderating centre and of the arresting fibres 

 of the pneumogastric. The solution is prepared as follows : 



Hydrochloride of morphine . . .3 grains. 



Sulphate of atropine . . . . '3 grain. 



Distilled water . . . . . 2i fluid drachms. 



This solution is injected in the proportion of five minims per 

 pound of body-weight. In twenty to twenty-five minutes the solution 

 produces its effect, and chloroform inhalation can be commenced. 

 A drachm or two is sufficient to produce complete anaesthesia, 

 which can be prolonged for one or two hours. The solution used in 

 man is as follows : 



Hydrochloride of morphine . . • i^ grains. 



Sulphate of atropine .... "08 grain. 



Distilled water 2-I- fluid drachms. 



