694 PASSIVE IMMUNIZATION SERUM THERAPY 



5. An assistant holds the loaded cylinder and tubing; the operator 

 steadies the skin over a prominent vein and quickly inserts the needle. 

 A flow of blood indicates that the vein has been penetrated. The tub- 

 ing is then quickly and carefully attached, the tourniquet released by 

 unfastening the hemostat, and the injection given. As a rule, an eleva- 

 tion of the cylinder of two or three feet is sufficient. If swelling occurs 

 about the site of puncture and the patient complains of pain, the in- 

 jection is entering the subcutaneous tissue; when this occurs, the pinch 

 cock should be closed and the needle removed. It is then necessary to 

 make the injection into another vein or into the same vein at another 

 site. 



TECHNIC OF SUBDURAL INOCULATION 



In the treatment of epidemic cerebrospinal meningitis, influenzal 

 meningitis, and tetanus the specific serums are administered subdurally 

 by means of a needle introduced in the lumbar region. Recently sub- 

 dural injections of salvarsanized serum and weak solutions of salvarsan 

 itself have been advocated in the treatment of cerebrospinal syphilis, 

 tabes dorsalis, and paresis. Every practitioner should be prepared to 

 perform lumbar puncture for the purpose of securing cerebrospinal fluid 

 for making the Wassermann reaction and the bacteriologic, cytologic, 

 and chemical examinations, and the administration of serum is a rela- 

 tively simple matter when the puncture has been successfully made. 



The technic of lumbar puncture for the purpose of securing fluid for 

 diagnosis is described on p. 37. But when administering serum, and 

 especially in the treatment of meningitis, the clinical condition of the 

 patient and the danger of sudden collapse render it advisable and neces- 

 sary that the inoculation be given with the patient lying on his side. 



Methods. Two methods are now being employed. The older method 

 consists in injecting the serum by means of a syringe, and the later one 

 is a method whereby the serum is allowed to flow in by gravity. 



Not infrequently a patient will develop symptoms of collapse during 

 a subdural injection, and these have been ascribed to undue pressure, 

 the injurious action of trikresol or other preservative upon the respira- 

 tory centers, too rapid injection, and the introduction of too large a 

 quantity of serum. It is now apparent that in the past too little atten- 

 tion has been paid to the patient while the injection was being made, and 

 serum has usually been administered according to more or less fixed and 

 arbitrary rules, instead of being guided by the clinical condition of the 

 patient. 



