358 PRINCIPLES OF VETERINARY SURGERY 



while developing, threatens to effect an entrance into the 

 neighboring muscular plane, the synovial membranes or into 

 the large splanchnic serous membranes. 



The incision is made in the most dependent part in order 

 to facilitate the flow of pus. If sinuses, anfractuosities or di- 

 verticula exist, a counter opening is made. For superficial 

 abscesses simple tapping may be sufficient, but when the 

 cavity is one of any considerable size a liberal incision is es- 

 sential. For deep abscesses the incision must be made suc- 

 cessively through the different layers. 



Veterinarians frequently use the cautery instead of the 

 straight bistoury for this purpose. The cautery must be 

 brought to a white heat, and must be inserted into the fluct- 

 uating part by pressure and semi-rotation. By this method 

 the haemorrhage that follows is considerably less than with 

 the bistoury, and the cutaneous wound has not the same ten- 

 dency to close too rapidly. The trocar is specially used in 

 tapping abscesses that threaten to burst in the region of a 

 mucous membrane, but it offers no special advantages. 



When an abscess is opened should it be left to itself? In 

 the last stages it has been advised to currette the fleshy to- 

 menta from the pyogenic membrane in order to remove the 

 microbian cultures with which they are impregnated, but 

 this is a useless" precaution. This does not mean, however, 

 that nature must be left alone, as repair will be more speedy, 

 and the cure more rapid if the sac is well washed out with 

 a solution of carbolic acid to draw out the remainder of the 

 pus and disinfect the pyogenic membrane and thus facilitate 

 the constriction and reunion of the fleshy tomenta. Under 

 these conditions cicatrization rapidly supervenes. 



COLD ABSCESSES. 



It is difficult to draw a well-defined line of demarcation 

 between hot (acute) abscesses and cold (chronic) abscesses, 

 as between these two are all the intermediate varieties. 



