URETHRAL OPERATIONS. I17 



entrance. The catheter, which in the female may be of elastic 

 gum or metal, is guided gently by the forefinger into the orifice 

 of the urethra, this being found as a small opening on the floor 

 of the vagina, and carefully introduced in a slightly downward 

 and backward direction into the bladder. 



To pass the catheter in the male, the animal should be placed 

 on its back or side, the operator having both hands free to 

 manipulate the instrument and penis. The penis is forced 

 gently but firmly out of the prepuce, the latter being pushed 

 back at the same time and the catheter carefully introduced 

 into the urethra. Gentle pressure is then exerted, and the 

 catheter slowly passed into the bladder. Sometimes resist- 

 ance is met with when the instrument reaches the perineal 

 arch, but this can be readily overcome by withdrawing the 

 stylet for a short distance, and thus allowing the more flexible 

 canula to go forward by itself. 



Having thus introduced the catheter into the bladder, the 

 only remaining procedure is to carefully withdraw the stylet 

 and allow the urine to come away. 



Attention must always be paid to the cleanliness of the 

 catheter, and, before being introduced, the instrument should 

 be lubricated with some antiseptic, such as pure vaseline, 

 boracic acid ointment, or oil containing some antiseptic. 



Operation for Imperforate Urethra or Vagina. — An imper- 

 forate urethra or vagina is occasionally met with ; if the stoppage 

 occurs at its extremity, an incision with a scalpel will give im- 

 mediate relief. Precautions must be taken to prevent union of 

 the edges of the wound, either by making a fairly large orifice, 

 or by the application of the cautery.^ 



Removal of Calculi from the Urethra; Urethrotomy.— In 

 the dog and cat, particularly in male animals, small calculi are 

 occasionally met with in the urethral canal. They cause acute 

 pain during their passage through the urethra, and frequently 

 give rise to cystitis and even rupture of the bladder. They 



'Journal of Comparative Pathology and Therapeutics," Vol. IX., p. 155. 



