SERUM TREATMENT OF TETANUS 775 



3. For the rapid neutralization of toxin free in the body-fluids serum 

 should be given intravenously. In the treatment of tetanus from 10,000 

 to 20,000 units may be given by this route as early as possible. While 

 it is conceded that when the toxin has become firmly bound to the tissues 

 of the central nervous system dissociation by the use of antitoxin is not 

 possible, yet one can never know, in a given case, how firm this union 

 has become, and clinical results, supported by animal experimentation, 

 show that life may be preserved by large doses of antitoxin injected into 

 the blood. 



4. The experimental work of Pennin, 1 Park and Nicoll, 2 supported 

 by the clinical results reported by various observers, shows quite con- 

 clusively that the subdural route is a very efficacious and valuable avenue 

 by which to administer antitoxin in the treatment of tetanus. The serum 

 should be given by the gravity method, in exactly the same manner as 

 in giving antimeningitic serum. To insure its thorough dissemination 

 throughout the spinal meninges the antitoxin should be diluted, if 

 necessary, with normal salt solution. As a rule, the amount injected 

 should be slightly less than the amount of fluid withdrawn. In the 

 case of a "dry tap, " if the operator is reasonably sure of having entered 

 the canal, from 3 to 5 c.c. of serum may be injected. It is generally 

 necessary to repeat this injection within twenty-four hours. 



The reason for administering antitoxin subdurally is apparent when 

 it is remembered that neither the central nervous system nor the peri- 

 pheral nerves take up antitoxin direct from the blood (Park). Only 

 after very large intravenous doses are traces of antitoxin found in the 

 cerebrospinal fluid, and animals passively and actively immunized may 

 be rendered tetanic if the toxin is injected directly into the central 

 nervous system or into the nerve. While antitoxin injected subdurally 

 finally passes over into the blood, it will neutralize any free or dissoci- 

 ated toxin before the latter has developed any harmful tendency. 



5. To neutralize any toxin that may have been absorbed by a nerve 

 it may be advisable to inject antitoxin directly into the nerve, and these 

 intraneural injections under anesthesia are advised by Ashhurst, John, 

 and others as part of the rational treatment of tetanus. 



The technic of these injections has been described elsewhere. 



Prophylaxis of Tetanus. The most successful preventive treatment, 

 and practically the only successful curative one after the disease has de- 

 veloped, is by means of tetanus antitoxin. As a prophylactic remedy 

 this antitoxin exceeds in value even diphtheria antitoxin; therapeutic- 



1 Mitt. a. d. Grenzgebiet d. Med. und Chir., 1913. xxvii, 1. 



2 Jour. Amer. Med. Assoc., 1914, Ixiii, 235. 



