VETgirl October 2024 Beat e-Magazine

QUARTERLY BEAT / OCTOBER 2024

Other complications include reobstruction without stricture due to larger stones, bleeding from the surgery site, and increased risk of UTIs. A less common but potentially serious complication occurs when urine tracks subcutaneously, resulting in inflammation or even large areas of sloughed skin. P ost - op care It is CRITICAL that cats not lick at the urethrostomy site so an e-collar is mandatory for two weeks post-op. I prefer non-clumping litter so that it doesn’t clump on the surgery site. Owners can gently dab the surgery site but should not aggressively clean for fear of disrupting the mucosal healing. I usually get the cats back in two weeks post-op, examine the site, and pass an 8 fr red rubber tube (can almost always be done without sedation) to make sure stoma is adequate size. C at urethrostomies when a PU has failed or is not adequate : T ranspelvic and antepubic urethrostomies If a urethrostomy strictures, the first option is to move further cranially in the urethra to make a new PU. This is much easier if the PU was not adequately cranial the first time! If moving further cranially in the urethra is not possible then we go to a plan B. Two other urethrostomies can be considered, both performed with the cat in dorsal recumbency. My preference is a transpelvic urethrostomy. For this procedure, the urethra is tracked caudally to the caudal ischium. A 1-2 cm long x 5-8 mm wide rectangle of ischium is removed using rongeurs to localize the intrapelvic urethra. A longitudinal incision is made into the ventral aspect of this portion of the urethra (a catheter pass from a cystotomy can assist with locating this) and the urethrostomy is performed similar to a PU using both similar suture and suture pattern to make a stoma in the intra pelvic urethra. The second option, an antepubic or prepubic urethrostomy is performed by transecting the urethra as far caudally as possible from an abdominal approach. The urethra is then brought through a paramedian incision in the abdominal body wall. The end of the urethra is spatulated and a stoma is created to the ventral abdominal skin. C omplications and post - op care Both of these salvage options are technically challenging and have higher complication rates than a PU. The antepubic urethrostomy particularly has a high risk of peristomal dermatitis and stricture. The antepubic also has a high rate of recurrent UTIs and urinary incontinence due to the shorter length of the urethra and potential damage to the nervous plexus supplying it. The transpelvic has lower risk of incontinence but still risk for peristomal dermatitis and stricture as well at UTI. Owners need to be counseled carefully when these options are selected.

FELINE PERINEAL URETHROSTOMY I ndications Most common indication is repeated urethral obstructions. May also be indicated in cats that cannot be unblocked or for caudal urethral tears. S urgical technique Position can be either sternal with legs hanging over the table or dorsal (allowing for concurrent cystotomy or conversion to transpubic or antepubic urethrostomy). Pass a tomcat or other catheter into the urethra if possible. Incise the skin around the prepuce and scrotum and continue the dissection cranially to the level of the ischium. Transect the ischiocavernosus muscles from the ischium using bipolar cautery or sharp dissection. Sever the attachments of the penile tissue to the floor of the ischium sharply to allow the penis to be mobilized dorsally and caudally. It is helpful to clamp a hemostat or Allis tissue forceps to the penis and prepuce to maintain orientation and allow easier tissue manipulation during the dissection. Resect the retractor penis muscle off of the penis back to a level cranial to the bulbourethral glands. Make a longitudinal incision near the caudal end of the penile urethra over the tomcat catheter and back the catheter out slowly until the tip exits through this defect. Introduce a second tomcat catheter into the cranial portion of the urethra and the bladder. Use an 11-blade vertically to make a longitudinal incision in the urethra. The author finds that this is most easily done without jagged stops and starts by holding the blade vertically resting on the dorsal portion of the tomcat catheter. As the tomcat catheter is pushed cranially along the urethra, use the 11-blade to make a smooth cut in the dorsal urethra. Continue this cut to a level cranial to the bulbourethral glands. At this level the urethra should accommodate the thick part of a tomcat catheter or a mosquito hemostat to the boxlocks (hinge). Construct the stoma by placing 5 or 7 simple interrupted sutures around the dorsum of the skin incision and cranial urethral incisions. It is critical to suture the urethral mucosa to the skin. The author likes to use 4-0 or 5-0 Monocryl for the sutures, which are left to absorb, however, some surgeons prefer non-absorbable, which are eventually removed. Following construction of the dorsal stroma, the “drainboard” of the remaining urethral mucosa is constructed using the same suture in a simple continuous pattern down each side. Once 1-2 cm of drainboard has been completed, the remaining penis is amputated, and remaining skin defect is closed. The bladder should be flushed thoroughly with sterile saline post-op and express the bladder to make sure the cat has a good urine stream. C omplications and surgical errors Stricture is the most common and devastating complication, typically due to one of the following: 1. Failure to suture mucosa to skin; 2. Failure to dissect cranial to the bulbourethral glands where the urethra is wider; or 3. Cats grooming the site prior to healing. These patients must have an e-collar during recovery.

TO PEE OR NOT TO PEE? THAT IS THE QUESTION: WHEN AND HOW TO MAKE A URETHROSTOMY IN MALE DOGS AND CATS

DR. CHRIS RALPHS DACVS Ocean State Veterinary Specialists

In this VETgirl Webinar To Pee or Not to Pee? That is the Question: When and How to Make a Urethrostomy in Male Dogs and Cats on June 12, 2024, Dr. Chris Ralphs, DACVS reviews all you need to know about becoming a derm rockstar! In case you missed the webinar, watch it again HERE or read the cliff notes below!

side to avoid excessive bleeding and to be centered on the urethra to maintain mucosa on each side for closure. The penile mucosa is then sutured to the skin on either side of the incision to form the stoma using 4-0 or 5-0 absorbable monofilament such as Monocryl in a simple interrupted or simple continuous pattern. The author prefers 5 simple interrupted sutures at the caudal edge closest to the bladder and then simple continuous down each side. These sutures are typically left to be absorbed. Pass a catheter from the stoma to the bladder to ensure patency and then close any remaining skin defects. C omplications and surgical errors Strictures are gratifyingly uncommon in this surgery. However, hemorrhage is very common and annoying. Make sure owners are aware that there will likely be bleeding from the site for a week or more. If bleeding continues past two weeks it may require a revision. If too much scrotal skin is left, there can be irritation of the skin. Some dogs may urinate on their legs and are more prone to UTIs. P ost - op care E-collar for two weeks. Owners should gently dab, not scrub, at the surgery site if cleaning is needed.

MALE CANINE URETHROSTOMY I ndications Canine urethrostomy is performed less commonly than feline and can be performed for several reasons including stricture, persistent stone formation (e.g., dalmatians and bichon frise), trauma, or neoplasia. L ocation The most common location to perform a urethrostomy is scrotal because the urethra is wide and superficial at this level. It can also be performed prescrotal, if the dog is not to be neutered, or perineal, although the urethra is deeper and more vascular at the perineal location so this is less common. T echnique An ellipse of scrotal skin is excised over the urethra to avoid urine scald. The retractor penis muscle and other subcutaneous adventitia is moved off to the side of the urethra at this site. An 8-10 fr red rubber catheter can be passed to aid in identification and safe incision into the urethra. A 2 to 4 cm longitudinal incision is made on the ventral surface of the urethra caudal to the os penis. Care is taken to not incise into the tunica on either

WEBINAR HIGHLIGHTS

VETGIRL BEAT EMAGAZINE | VETGIRLONTHERUN.COM

Made with FlippingBook - Online Brochure Maker