444 TETANUS 



from inoculation with the minimum lethal dose of bacilli or 

 toxin. If symptoms had begun to appear, 100 c.c. at once would 

 be necessary, and therefore, in such cases, more powerful sera 

 are used, e.g., one of which one grm. would protect 100,000,000 

 grms. weight of mice. 1 The potency of such sera is maintained 

 for several months if precautions are taken to avoid putrefaction, 

 exposure to bright light, etc. To this end '5 per cent, carbolic 

 acid is usually added, and the serum is kept in the dark. In 

 a case of tetanus in man, 100 c.c. should be injected within 

 twenty-four hours in five doses, each at a different part of the 

 body, followed up by further injections if no improvement takes 

 place. Intravenous injection of the antitoxin has also been 

 practised, and, in cases which we have seen treated in this way, 

 has seemed to give better results than those obtained by the 

 subcutaneous method. The serum is warmed to the body tem- 

 perature and slowly introduced into a vein in the arm, the pulse 

 and respiration being carefully watched during the proceeding. 

 Ten to twenty c.c. can be injected every few hours, and in 

 all 100 c.c. should be given in as short a time as possible. 

 Henderson Smith has shown that when antitoxins to toxins of 

 the tetanus group are injected intravenously a high concentration 

 in the body fluid is maintained for some time, and the oppor- 

 tunity for neutralisation of toxin is thus great. He suggests 

 that both intravenous and subcutaneous injections should be 

 simultaneously practised. The former gives quickly the con- 

 centration which is desirable, and when the antitoxin injected 

 intravenously is beginning to be eliminated, that introduced 

 hypodermically comes into the circulation and the concentration 

 is maintained. The antitoxin has also been introduced intra- 

 cerebrally, very slow injection into the brain substance being 

 practised, but no better results have been obtained than by the 

 subcutaneous method. 



Many cases of human tetanus have been thus treated, but 

 the improvement in the death-rate has not been nearly so 

 marked as that which has occurred in diphtheria under similar 

 circumstances. As in the case of diphtheria, however, the 

 results would probably be better if more attention were paid 

 to the dosage of the serum. The great difficulty is that usually 

 the presence of the tetanus bacilli is not suspected till they have 

 begun to manifest their gravest effects. In diphtheria a well- 

 marked clinical feature, sore throat, draws attention to the 



1 The antitetanic serum sent out by the Pasteur Institute in Paris has a 

 strength of 1 : 1,000,000,000. Of this it is recommended that 50 to 100 c.c. 

 should be ^injected subcutaneously in one or two doses. 



