128 CLINICAL BACTERIOLOGY AND HEMATOLOGY 



LUMBAR PUNCTURE 



Fluid may be removed from the spinal meninges for a bacterio- 

 logical or other examination by means of Quincke's lumbar 

 puncture. The information furnished by this means is often of 

 very great value ; in fact, Osier says that " during the past ten 

 years no single measure of greater value in diagnosis has been 

 introduced." The process is simple, easy, and entirely devoid of 

 danger, and can be carried out without an anaesthetic. I have 

 now performed this operation over three hundred times, and have 

 only seen bad after-effects (in all cases temporary) in three or four 

 cases, in all of which eucaine had been used as a local anaesthetic. 

 I have therefore abandoned the use of this drug, and now employ 

 only ethyl chloride locally. On the other hand, a very large 

 amount of benefit is often derived from it, and it must be regarded 

 as the most useful therapeutic agent at our disposal in the treat- 

 ment of meningitis, especially chronic forms ; one case at least of 

 tuberculous meningitis has been cured by repeated punctures. 

 It acts, of course, by relieving the high intracerebral tension and 

 by removing some of the toxin-containing cerebro- spinal fluid. 

 In basic meningitis I have seen several cases in which the 

 patient's life was saved by it : the urgent pressure symptoms 

 were relieved on several occasions, the relief lasting a few days, 

 and he was thus enabled to tide over the attack, uninterrupted 

 and complete recovery resulting. In a case in which I performed 

 the operation recently a single puncture was followed by imme- 

 diate relief, though the symptoms were most grave, and there has 

 been at present (after a month) no recrudescence. Great temporary 

 relief may also be given in the severe headache of uraemia and 

 chlorosis. 



It should never be done on a " walking " patient, since if too 

 much fluid is drawn off headache or vomiting are said to result ; 

 these soon pass off if the patient rests in bed. 



Requisites. — -i. A suitable needle. In children the spinal 

 meninges will be reached at a depth of 3 to 4 centimetres (roughly 

 I to 1^ inches), whilst in adults the depth may be twice as great. 

 The needle should not be less than -z^ inches long for an infant 

 and 4 inches for an adult, and should be sharp and strong. An 

 antitoxin needle will usually serve very well. A syringe is 

 unnecessary, and the fluid should never be sucked out of the 



