190 DEPRESSANTS TO PERIPHERAL NERVES 



is painful when inflammation exists, and in such cases it is preferable 

 to block the nerves supplying the parts. Schleich also believes that 

 the local anemia due to pressure of the large amounts of solution aids 

 in decreasing sensation. He also asserts that similar injections be- 

 neath the periosteum permit of operations on the bones. The anes- 

 thetic lasts about twenty-five minutes. He recommends three solu- 

 tions of different strengths, as follows : 



Solution 12 3 



Cocaine hydrochloride gr. iv (0.25) gr. ij (0.12) gr. Vs (0.012) 



Morphine hydrochloride. ... gr. 1/2 (0.03) gr. 1/2 (0.03) gr. Vio (0.006) 



Sodium chloride gr. iv (0.25) gr. iv (0.25) gr. iv (0.25) 



Sterilized distilled water. . . fS iv (120) fS iv (120) fS iv (120) 



To each of these solutions 3 minims of a 5 per cent, solution of 

 phenol are added. The second solution is the one most used, the 

 first where acute inflammation is present and the third where it is 

 necessary to use repeated injections. The effect of these injections 

 may be considerably increased if adrenaline chloride in the propor- 

 tion of 1 — 20,000 is added to the mixtures. This method of anes- 

 thesia has been given considerable trial and may be satisfactory for 

 minor operations, but is not satisfactory for deep cutting operations 

 or for operations upon the nerves. 



COCAINE SUBSTITUTES 



On account of certain drawbacks to cocaine, especially its poison- 

 ous nature, decomposition on sterilizing, poor keeping qualities in 

 soliition and occasional idiosyncrasy to the drug, several products 

 have been advanced as substitutes for it. The following are the 

 most important : 



Novocaine (para-aminobenzoyldiethylaminoethanol hydrochlor- 

 ide) occurs as fine colorless needles that melt at 156° C, and are 

 soluble in 1 part of water and about 30 parts of alcohol. Its solu- 

 tions are neutral. Its aqueous solutions may be boiled without un- 

 dergoing change. Toward alkalies and alkaloidal reagents it be- 

 haves like alkaloidal salts. Injected subcutaneously it manifests a 

 strong but transient anesthetic action but is said to be absolutely un- 

 irritating. Braun combines the active principle of the suprarenal 

 capsules with it to increase its action and says that so combined, it is 

 as powerful as cocaine. It prodirces no effect upon the arterioles, 

 and is not absorbed from intact mucous membranes, so is not suitable 

 for operations upon the eye and throat, where dependence is placed 

 upon the simple application of the drug. According to Schley, it is 

 only about Ye as toxic as cocaine. 



It is used in solutions of from 0.5 to 2 per cent. Crile recom- 

 mends a solution of 1 — 400 to anesthetize the field of operation be- 

 fore cutting and thus prevent surgical shock to the tissues. This is, 

 of course, supplementary to general anesthesia. 



