Chapter 14: Table of Contents
Ventral Cystotomy Incision
Perform a ventral cystotomy incision. Although it has been claimed that a dorsal cystotomy incision minimized post-operative leakage of urine, decreased the likelihood of calculus formation on intraluminal suture material, and resulted in fewer adhesions between the bladder and body wall – this is not supported clinically. There are no significant advantages to performing a dorsal incision and this approach is not recommended. A ventral cystotomy incision provides better visualization of the bladder neck and trigone allowing cystic calculi to be retrieved more easily. It is also easier to avoid the ureteral openings (located dorso-laterally) through a ventral incision, which reduces the risk of including the ureters in the bladder wall closure.A urinary catheter should be placed preoperatively (or intraoperatively in male dogs) to reduce the risk of calculi entering the urethra and to allow retrograde urethral flushing to be performed prior to cystotomy closure.
After placing two midline stay sutures at each end of the proposed cystotomy incision (one closer to the apex and one closer to the trigone), perform a 3-4 cm ventral, midline cystotomy incision that extends towards the trigone but not closer than 1-2 cm from the urethra. First stab the bladder wall, then extend the incision with Metzembaum scissors. Place additional lateral stay sutures to facilitate visualization or use a curved Carmalt forceps to distract the bladder wall edges laterally. Collect a bladder wall sample (including mucosa) for culture or histopathology as required. Remove any urinary calculi from the urinary bladder with forceps or an appropriately sized bladder spoon. Digital palpation is appropriate but requires the surgical gloves to be discarded and replaced prior to closing. Once all visible calculi have been removed, ask an unsterile assistant to pulse flush sterile saline through the urinary catheter as it is slowly removed. With a sterile urinary catheter, antegrade flush can also be performed from the bladder towards the urethral papilla but this is not recommended in male dogs as it may lodge remaining calculi within the penile urethra or the os penis. Once all calculi are removed, the bladder is closed routinely.