96 URETHROTOMY. LITHOTOMY 



quires time and patience, since as a rule it is not possible to 

 encompass the entire calculus with the forceps. That is, 

 the narrowness of the neck of the bladder prevents the 

 sufficiently wide opening of the forceps. The stone con- 

 sequently must be gradually broken off at its periphery and 

 the individual pieces of calculus removed. The character 

 of the surface of the stone has an evident bearing upon the 

 practicability of lithotripsy. 



The surgical dilation of the pelvic urethra with the 

 lithotome is usually far more practical than the crushing of 

 the stone. Introduce the instrument and divide the urethra 

 upward on the median line as the instrument is withdrawn. 

 In order to prevent injury to the rectum, it should be 

 emptied of feces before the operation is undertaken. After 

 the removal of the stone, theoperator may push the catheter 

 again over the ischial arch and unite the lips of the wound 

 in the urethral mucous membrane by means of intestinal 

 sutures. Flush the bladder and urethra by means of a 

 warm, 3 per cent, boric acid solution injected through the 

 catheter and then withdraw the^latter. Finally, suture the 

 skin wound and insert a drainage tube or antiseptic gauze 

 in the lower angle. 



Or the whole wound may be left entirely open and dressed" 

 daily with antiseptics. In case the pelvic urethra has been 

 divided, the suturing of the external wound is of question- 

 able utility. 



(For student practice on an anaesthetized horse, intro- 

 duce a stone into the bladder through the urethral wound 

 and practice grasping and removing it with the lithotomy 

 forceps.) 



27. AMPUTATION OF THE PENIS 

 Figs. 41, 42, 43 



Instruments. Scalpel, elastic ligature, strong silk suture, 

 strong piece of tape i m. long, artery and compression 

 foi ceps. 



