Bladder, Urethra and Ureters

How to – Perineal urethrotomy, equine


Urinary obstruction secondary to urolithiasis or other obstruction (eg tumor). Access to the bladder for diagnostic or therapeutic procedures.

Relevant anatomy

Preoperative management

Food restrictions:



Tetanus prophylaxis is recommended. 

Local blocks:


This procedure is usually done standing under epidural anesthesia. Pass a urinary catheter to better identify the urethra. Preop antibiotics and NSAIDs are routine. Clip and prep the area below the tail. Secure the tail away from the surgery field.

Surgery Supplies: 

Surgical procedure

Starting a few cm below the anus, make a midline incision 6-8 cm in length. Continue on midline between the paired retractor penis muscles using sharp and blunt dissection. You should be able to palpate the catheter (have someone move it if you aren’t sure). Dissect down to the catheter. Eventually you should incise the urethra longitudinally (we don’t want to transect it). The lining of the urethra is a shiny white and you should be able to see the catheter and pass an instrument up and down the urethra. Your patient can now urinate and get to a hospital for further treatment as indicated!

Postoperative care






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Large Animal Surgery - Supplemental Notes Copyright © by Erin Malone, DVM, PhD is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.