perineal urethrostomy for tom cats

What You Need to Know about Perineal Urethrostomy in Cats

Just like human beings, animals can suffer from illnesses and medical conditions that will require treatment and sometimes surgical procedures. One of these is known as perineal urethrostomy also referred to as PU.

In medical terms, “tomy” means opening. Thus, this procedure means to create an opening in the urethra, with the incision located in the perineum, between the scrotum and rectum of the animal, more often in cats and dogs. In this particular topic, we will talk about perineal urethrostomy done on a male cat.

As opposed to urethrotomy, which is a temporary opening, urethrostomy is permanent. It is usually performed on cats suffering from urine obstruction caused by bladder stones, protein plugs, scarring or trauma. If any of these conditions is not corrected, this can lead to urinary tract infection, loss of bladder tone and a rapid progression to death.


When is surgery recommended?

Cats that suffer from urethral obstruction can be unblocked and managed with medication and proper diet. However, if this condition recurs or does not fully resolve, the cat may need to go under the knife. Also, if urine flow is obstructed as a result of trauma or scarring of the urethra, the only remedy for this is surgery.


How is Perineal Urethrostomy done on a tom cat?

Similar to all surgeries, there will be pre-operative tests that are needed to be done depending on the severity of the condition and the age of the cat. These may include: abdominal ultrasound, blood tests, urinalysis and radiographs.

The general anesthesia and the operation can last between 45 minutes to two hours. But normally, the entire operation is usually about 50 minutes.

After the induction of the anesthesia, the cat is placed on the surgical table, in prone position.  Once the penis is freed from its attachments, an incision will be made in the dorsal urethra up to an in between the bulbourethral glands.  Next, the urethra is sutured open with to the skin using a small suture (4-0 or 5-0) on a cutting needle.  Ideally a complete inert non absorbable suture is used as this will cause very little to no inflammation.  Unfortunately, not all cats are amenable to having the sutures removed 10-14 days later!  Therefore many surgeons opt to use a short acting absorbable suture (Vicryl RapideTM). This suture will dissolve in about 14 days.


Post-operative Care

After the surgery, pain management is of prime importance.  These cats are very much in pain, and will not urinate if the pain is not properly managed.  It is also important to use an elizabethan collar to keep the feline from licking the surgical site that can lead to wound dehiscence.

It is also recommended to monitor the cat for any discharge. Urine color may be a little reddish because of the procedure but after a few days, it should normalize.  Incontinence may be present post-operatively.  This may be due to infection or pain.  It is important to accurately assess and manage the patient.


Perineal urethrostomy is a safe and life saving procedure.  When performed properly, complications are very few.  Stenosis of the opening is a big concern but occurs most commonly because the urethrostomy was not created “high enough”.  It is very important that the new opening be in the pelvic urethra.  Come take the course and learn how to do it right and save the lives of many cats!



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