472 GERMICIDES — DISINFECTANTS 



THERAPEUTIC CLASSIFICATION OP DISINFECTANTS 



General Disinfectants. There are many disinfectants used for 

 general purposes. For cesspools, copperas or lime, chlorinated lime, 

 naphthalin and the cheaper preparations of cresol are generally em- 

 ployed. 



For Stables. All litter and articles of little value should be 

 burned. Blankets may be disinfected by steam, or boiling, or by 

 soaking in a disinfectant solution. Harnesses, halters, etc., by a dis- 

 infectant solution ; woodwork after thorough cleaning, by bichloride 

 of mercury, coal tar preparations or formalin. On account of the 

 difficulty in sealing barns and stables the last named preparation is 

 not of great service in many cases. 



Surgical Disinfectants. One of the most important uses of 

 germicides or disinfectants is in surgical technique and aseptic or 

 antiseptic handling of wounds. Bichloride of mercury is one of the 

 most popular disinfectants for general use. It is cheap, soluble and 

 very effective but possesses the disadvantages of being very poison- 

 ous, corrosive to instruments, irritant to tissues and is readily decom- 

 posed into inactive compounds by proteids. It is said that the 

 last mentioned objection may be overcome by the addition of a weak 

 acid (citric or tartaric). For the preparation of the field of opera- 

 tion a solution of 1 : 1000 or 1 : 500 should be used and preferably in 

 alcohol. See Harrington's solution, p. 431. For large wounds and 

 cavities 1 : 10,000—5000 and for small wounds 1 : 2000 to 1 : 1000. 

 It should not be used on serous surfaces as it is irritant. 



Phenol by many is not regarded as being so efficient but neverthet- 

 less is widely used. It is particularly destructive to pus organisms. 

 It is soluble, is not very much affected by proteids and only dulls 

 metallic instruments. On the other hand, it is very toxic and has 

 a benumbing action on the hands. It is used in aqueous solutions 

 of from 1 to 5 per cent, upon open wounds and in the pure form for 

 knives and other instruments which are injured by boiling. 



Formaldehyde is a very active disinfectant but is too irritating 

 for general purposes. Solutions of from 1 to 2 per cent, of 

 formalin are occasionally used for wounds and a 2 per cent, solution 

 for instruments. 



Practical Disinfection of the Hands. There are several meth- 

 ods for disinfection of the hands of the operator. A few will be 

 mentioned. Fiirbringer's method is first, to clean the nails well 

 and scrub the hands with soap and water and brush for several 

 minutes, then soak in alcohol for at least one minute, and then plunge 

 into a 1 : 500 aqueous solution of bichloride of mercury while stiU 

 wet. The alcohol aids in removing the soap and grease from the 

 creases of the hands and at the same time favors the penetration of 

 the antiseptic. Another method is to scrub the hands as mentioned 



