548 SHAKLEE. 



results upon which to base the treatment of convulsions by the use of 

 . general anaesthetics. 



The method of the present study in its main features is as follows: 

 The preparation of the animal (1) for intratracheal insufflation with 

 air mixed by means of the anaesthetic regulator 3 with the vapor of the 

 anaesthetic; and (2) for intravenous injection of drugs and of Ringer- 

 Locke solution warmed to the body temperature. In some cases a pre- 

 limina ry small dose of morphine, or atropine, or both is given. Since the 

 non-anaesthetized animal which has not been treated with curarine, is 

 thrown at once into a violent tetanic convulsion by the intravenous 

 injection of strychnine sulphate in the dosage used, and since the spasm 

 of the respiratory muscles may render the introduction of the anaes- 

 thetic difficult and hazardous, an attempt is made to bring the animal 

 to such a stage of anaesthesia before the administration of the strych- 

 nine that no eonvvdsions or only slight ones would result. At times 

 the anaesthetic is administered by means of insufflation in connection 

 with the anaesthetic regulator, at other times it is automatically admin- 

 istered by the dog's inspiration, the tracheal catheter being in con- 

 nection with the regulator. The amount of Ringer-Locke solution 

 injected in each case is equivalent to about one-tenth of the body weight 

 and the duration of the injection varies from one-half hour to two hours. 

 The quantity of strychnine administered varied from 0.6 to 0.8 milli- 

 gram per kilogram of animal. In control experiments 0.4 milligram 

 per kilogram proved invariably fatal to the untreated animal. When 

 morphine or atropine is used, the quantity of morphine is sufficient to 

 produce more or less depression and that of atropine large enough to 

 liberate the heart from vagus inhibition. 



The two protocols given below will show the course of the more 

 successful cases of treatment with chloroform: 



Protocol No. J h — Dog No. 4, 12.5 kilos g , Bra. & Wh., 5 years old ( ?), seems 

 healthy, rather lean. 



8.25 a. m.: 1 cubic centimeter morphine sulphate (4 per cent aqueous solution) 

 injected subcutaneously. 



8.38: Pupils small. 



8.45: Chloroform was administered by means of a cone. [In spite of care, an 

 overdose of chloroform was given in this case and heart and respiration stopped. 

 A tracheal catheter was inserted through the mouth and artificial inspiration by 

 insufflation together with thoracic (heart) massage were begun. The heart soon 

 began to beat slowly but it was only after some minutes and after repeated strong 

 traction on the tongue that voluntary respiration was initiated]. The tracheal 

 catheter (a piece of rubber gas tubing) was connected with the anaesthetic regu- 

 lator and valve set 4/6 full, i. e. was moved 4/G of the part of a revolution neces- 

 sary to send all the air through the anaesthetic bottle. 



9.07 : Chloroform 4/6 does not keep this dog under, owing to the excess in 

 size of glottis over tracheal catheter. Pulse soft and irregular. 



3 Loo. cit. 



