loo URETHROTOMY. LITHOTOMY. 



25. URETHROTOMY. LITHOTOMY. 

 FIG. 7, 8. 



Objects. For the removal of calculi from the bladder or 

 urethra or performing other operations on these parts. 



Instruments. Catheter, convex scalpel, scissors, artery 

 and compression forceps, tenacula, lithotome, lithotomy 

 forceps, lithotrite, absorbent cotton, drainage tube, suture 

 material. 



Technic. Urethrotomy may be performed on horses in 

 a standing position, the hind feet being secured with hobbles. 



It is best, however, to operate under anaesthesia with the 

 patient in lateral or dorsal recumbency, either on the operat- 

 ing table or cast, being careful to secure as gently as possi- 

 ble, having first emptied the bladder if practicable, since 

 rupture of an overdistended viscus may readily occur during 

 violent struggles by the animal. 



The point of operation will depend upon the location of 

 the calculus or other obstacle. If it is found in the pelvic 

 portion of the urethra or in the bladder, the operation is 

 made at the ischial notch, Fig. 8. First the penis is drawn 

 out from the prepuce and the catheter introduced into the 

 urethra and pushed upward until it has passed the ischial 

 notch. After disinfection of the skin, render it tense and 

 make a 5 cm. long incision on the median line at the ischial 

 arch through the skin, bulbo-cavernosus muscle, spongy 

 portion of the urethra, and the urethral mucous membrane 

 down to the catheter. Fig. 8, k. In order to prevent infiltra- 

 tion of urine after the operation, special care is to be taken 

 to make the lower end of the wound slanting in such a 

 manner that the inner margin is higher than the outer. 



After the catheter has been drawn back away from the 

 ischial arch, introduce the lithotomy forceps into the urethra 

 or bladder, grasp the stone and draw it outward in its natural 

 direction. The grasping of the stone by the forceps is 

 materially aided by means of the left hand introduced into 



