2 Surgical Diseases and Surgery of the Dog 



it is also ready existent in the form of certain natural secretions, 

 especially those of serous cavities, such as joints and the pleural 

 sacs, where septic surgical interference is commonly followed by 

 pyogenic processes, particularly when abnormal accumulations of 

 fluid are present. The normal peritoneum must be excepted on ac- 

 count of the well-known comparative immunity it enjoys, probably 

 by reason of the numerous recesses existing between the coils of the 

 viscera where there is a chance for microbic activity to become local- 

 ized, the pleura and joints on the other hand offering an unbroken 

 extent of space for the accumulation of fluids. Hence, the object 

 should always be to avoid the creation of putrescible matter, but 

 inasmuch as this is a matter of impossibility in some parts of the 

 body, it is necessary to take precautions to prevent infection by the 

 practice of aseptic methods, or resort to the alternative of drainage. 

 Aseptic methods are indispensable in operations involving interfer- 

 ence with the thorax, the' cerebro-spinal canal, joints, and deeply 

 situated organs such as the thyroid gland ; they are not so necessary 

 when the peritoneum is concerned, excepting when ascites is present, 

 but are advisable as a precautionary measure; they are also expe- 

 dient in operations on the surface of the body but can be dispensed 

 with where local infection has already occurred, as in wounds and 

 abscesses. 



The preliminary steps in an operation on the lines indicated 

 above consist of sterilization of instruments and material and dis- 

 infection of the hands of the operator and the cutis in the area of 

 operation. 



Sterilization of Instruments. Instruments are best sterilized 

 by boiling for at least ten minutes, and if some powdered carbonate 

 of soda is added to the water to the amount of one drachm to the 

 pint, so much the better. Sodium carbonate dissolves the capsules 

 of the germs and the latter are destroyed in much shorter time, and 

 moreover, it inhibits rusting. Chemical disinfectants are unreliable 

 but should be used to receive the instruments during the course of 

 the operation to prevent fresh contamination. For the latter pur- 

 pose a solution of carbolic acid (5:100) is suitable. 



Sterilization of Hands. The hands of the operator always re- 

 quire thorough cleansing. They should first be scrubbed in hot 

 water and soap, particular attention being bestowed on the nails. 

 They should then be immersed for a few minutes in a strong solu- 



