70 ANTISEPTIC AND ASEPTIC METHODS. 



dressings. Antiseptic treatment of wounds might never have survived 

 had not observance of cleanliness largely assisted it. Contrary to 

 the belief generally held when antisepsis was introduced, entrance 

 of air into wounds is little to be feared, and atmospheric germs can 

 be almost disregarded. In veterinary surgery asepsis will probably 

 never obtain the same favour as antisepsis. Strictly considered, 

 however, antisepsis and asepsis do not stand in opposition, but 

 rather form mutual complements of each other; aseptic methods 

 being preventive, antiseptic curative, their association is often advan- 

 tageous. Antisepsis is resorted to when the region of operation 

 includes a suppurating wound, a fistula, or an ulcer, or when reunion 

 by first intention has failed. Antiseptics are then employed to 

 disinfect the seat of operation, the hands, the instruments, and the 

 dressing materials. The aseptic method, on the other hand, is 

 applicable to operations on infection-free tissues which might become 

 inflamed under the action of antiseptics, to cases of limited necrosis 

 and to intoxications ; but if asepsis can be ensured, it is useless to 

 apply to healthy tissues strong antiseptic solutions. Of the two 

 principles — •" antisepsis before and during," " antisepsis before, 

 asepsis during "—the former is preferable in our practice on account 

 of the chances of the wound, the hands, and instruments becoming 

 infected during operation. Even in human surgery, where, thanks 

 to better surroundings and to special apparatus, rigorous asepsis 

 can much more readily be obtained, and where the operator can 

 count on highly skilled assistants, antisepsis nevertheless has many 

 adherents. 



Wound infection is caused by the presence of pathogenic bacteria, 

 which sooner or later develop and multiply, and by their activity 

 or their products set up irritation of the tissues, inflammation, 

 suppuration, and in certain cases, general infection of the body. 

 Among the micro-organisms causing surgical infections micrococci 

 and bacilli stand pre-eminent. Whilst the former are usually quickly 

 killed by heat and the principal disinfectants, the latter resist to a 

 varying degree, depending on whether they are present in the form 

 of rods or exist as spores. The adult bacilli are easily killed, 

 the spores on the other hand are strongly resistent. Certain spores, 

 like those of tetanus and anthrax, exhibit most extraordinary 

 vitality. 



When dry, microbes resist the action of heat and antiseptics to 

 a higher degree and for a longer time than when moist. The most 

 convenient method of destroying them is exposure to moist heat. 

 Whilst steam at 212° F. kills the majority of pathogenic microbes, 



