LUMBAR PUNCTURE 177 



perforating it : when this is the case a short sharp push with 

 the wire will probably puncture the membrane, and the point 

 of the needle will slip in. A piece of steel wire is best. 



Since cultures may have to be taken, it is advisable to have 

 some sort of a handle which may be sterilized with the needle 

 and avoid any necessity for a very elaborate sterilization of 

 the hands. I use a pair of artery forceps, one blade of which 

 is passed inside the barrel and the other outside, and the in- 

 strument clipped on. The two are sterilized together and the 

 forceps used as a handle, and not removed until the puncture 

 has been made. Where a sterilizer large enough to take the 

 two instruments fixed together is not at hand the needle may 

 be placed point downward in a test-tube half full of water, 

 and the forceps inserted as far as it will go by its side. The 

 tube is boiled for ten minutes and the needle removed by 

 clipping it with the forceps, as above. The handle will not be 

 sterilized, but that does not matter. 



I have devised a curved needle with a handle fitting into a 

 socket (Fig. 28), which also answers well. It has the- advan- 

 tage that it can be put in a wide tube plugged with cotton- 

 wool, sterilized by dry heat, and taken to the bedside ready 

 for immediate use. 



2. Materials for disinfection of the patient's skin. I prefer 

 tincture of iodine followed by acetone. 



3. Apparatus for boiling the needle in a dilute solution of 

 washing-soda, or for sterilizing it in hot oil.* 



4. Spray for local anaesthesia. If this is used the hard 

 plaque of skin adds considerably to the difficulty of the opera- 

 tion. If, however, the region be frozen twice, and allowed to 

 thaw after each freezing, the skin will be found to have re- 

 sumed its normal texture and to be very fairly anaesthetic. 



5. Two or three test-tubes sterilized by dry heat and plugg'ed 

 with dry cotton-wool. 



6. If cultures are to be taken, the tubes of medium should 

 be inoculated at the time of the operation if possible. The 

 medium required will depend to a great extent upon the nature 

 of the organism which is expected. If there are no indica- 



* If possible, the needle should be sterilized by dry heat previous to the 

 operation, and kept in a tube plugged at both ends with cotton- wool, as in 

 the method recommended for the collection of blood for bacteriological 

 examination. 



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