COCAINE 189 



the cornea ; necrotic area or sterile abscess at the point of injection. 



2. After absorption, excitement and delirium. 



3. Sudden collapse after usual doses in .susceptible cases, but not 

 often in animals. 



Therapeutics. 



1. Externally. Cocaine or its synthetic chemical substances or 

 substitutes are the agents most generally employed for local anes- 

 thesia. The operations most suitable for local anesthesia are : 



Removal of tumors Operations on eye and throat 



Tenotomies Operations on the feet 



Firing Operations on mucous 



Neurectomies membranes, etc. 



2. To dilate the pupil and is superior to atropine in many cases. 



3. To detect obscure lameness by injecting a solution over the 

 nerves supplying the part and thus removing all sensation beyond the 

 point of injection. 



4. Internally. It has been used as a central nervous stimulant 

 in shock and collapse as in chloroform poisoning or narcotic drugs. 



5. To check nausea. Cocaine and other members of the group 

 may be useful to check nausea and vomiting of cats and dogs. 



6. General anesthetic. Eitter, in 1909, obtained in dogs by 

 injecting 10 mils of a 1 — 3 per cent, solution intravenously, general 

 anesthesia lasting foi 15 to 30 minutes. The animals remained 

 avs^ake, but quiet and indifferent and insensitive to pain. 



7. Intravenous local anesthetic. Bier produced anesthesia in 

 the limbs by placing a tourniquet above and below the point to be 

 anesthetized and injecting the cocaine solution directly into the vein. 

 This method is used Considerably by some surgeons but has not been 

 taken up by veterinarians to any extent. There is said to be some 

 danger of clotting of the blood. 



8. Spinal analgesia. See p. 186. 



Strengths of Solution. A solution of from 1 — 2 per cent, is 

 used for the relief of pain, but a stronger solution (4 per cent.) is 

 required to produce complete anesthesia as in cutting operations. 

 Four per cent, solutions may be too strong for application to the eye 

 except for very brief periods. 



Sehleich suggested the use of solutions of different strengths (and 

 with morphine without reason) for the infiltration method. This 

 consists in injecting a relatively large amount — up to 200 mils (6 

 fluidounces) — of a solution of 1 :10,000 in physiological saline 

 through a fine needle and permitting it to permeate the tissues about 

 the region to be operated upon. Relatively smaller amounts of 

 solutions of 1 :1,00C) may be used in the same way. The solu- 

 tion, in human work, is injected into — not beneath — the skin at 

 first, and then into the underlying tissues successively. This method 



