METHODS OF INOCULATION 



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3. The injections are best given in a vein at the elbow. The arm- 

 about this region should be scrubbed with hot water and soap, followed 

 by alcohol and 1 : 1000 bichlorid of mercury solution, or liberally painted 

 with tincture of iodin. A firm tourniquet is then applied above the 

 elbow; a single firm turn of rubber tubing held by a hemostat is quite sat- 

 isfactory, as when the vein has been entered the tourniquet should be 

 quickly released with the least movement and disturbance possible, and 



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FIG. 140. METHOD OF MAKING INTRAVENOUS INJECTION BY GRAVITY. 



This method is suitable for the intravenous administration of salvarsan or anti- 

 streptococcus serum, etc. The needle has been entered into a prominent vein 

 (indicated by a flow of blood); the tubing has been attached by means of a metal 

 tip which fits the needle easily and snugly; the tourniquet has been loosened and the 

 injection is being given. 



this arrangement answers all requirements. Sterile towels should be 

 placed about the arm and shoulder. 



4. About 20 c.c. or more of sterile distilled water or normal salt solu- 

 tion are then poured into the cylinder, and the cock opened until all air 

 has been expelled from the tubing. The fluid, serum, or salvarsan is 

 then poured into the cylinder. It is a good practice to filter the fluid, 

 through several layers of sterile gauze, especially when salvarsan is being 

 injected, in order to remove any bits of glass or other foreign bodies that may 

 be present. 



