THE PRACTICE OF DISINFECTION 163 



and abroad is the disinfection by iodin.. The patient 

 receives a full bath on the evening preceding the opera- 

 tion; any hairy portions of the skin are shaved, but no 

 dressing whatever is used; just before anesthetizing the 

 site of the operation is painted with a solution of iodin 

 in 50 per cent, alcohol and is covered with sterile towels. 

 The painting is repeated just before the operation. 

 The action of the iodin is the same as that of alcohol, 

 but is more pronounced and lasting. Its greatest dis- 

 advantage is the occasional development of an iodin 

 dermatitis; this is most likely to occur when the solu- 

 tion used is too strong (it should not be more than 5 

 per cent.); second, when the solution is old and con- 

 tains decomposition products of iodin; third, when the 

 skin is unusually tender, as in children; or, fourth, when 

 the skin has been previously washed with antiseptic 

 solutions or even plain water. In emergency cases no 

 previous w^ashing is resorted to, but the skin is cleaned 

 with a 1 per cent, solution of iodin in benzene two to 

 five minutes before the iodin is applied. 



Disinfection of the hands is closely allied with the 

 preparation of the patient, and, to a certain extent, 

 the same methods can be used for both. A ten minutes' 

 scrubbing with a bristle brush, using hot water and a 

 tincture of green soap, and giving special attention to 

 the skin folds at the base of the nails and the space 

 under the nails, is followed by rinsing in alcohol, ether^ 

 and bichlorid solution. Hands may thus be superficially 

 sterilized, but when they are immersed in hot solutions, 

 which induces sweating, countless bacteria will be 

 driven from the sweat and solmcoous glands to the 

 sterilized surface. This has been repeatedly proved by 



