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combined with a hypoallergenic diet.  The use of cyclosporine therapy has been well described and appears to have demonstrable benefit.  Unfortunately, cyclosporine remains prohibitively expensive for most of the very large dogs that typically suffer from perianal fistulae.  We have been utilizing a modified immunosuppressive therapy involving prednisone (given at immunosuppressive doses and tapered over a period of months) and azathioprine (given at 50 mg/m² PO SID x 7 days, then switched to EOD).  This must be combined with an exclusive hypoallergenic diet, such as those based on duck, rabbit, or venison.  Systemic antibiotics and cleansing of the fistulae are typically also utilized.  Treatment is continued for a minimum of eight to twelve weeks.  Most dogs demonstrate improvement in comfort and a reduction in the number or severity of the fistulae.  Surgical treatment at this point is usually less involved and more likely to resolve the fistulae.

Perineal Urethrostomy

This also can be a very successful surgery if properly performed and properly utilized.  Urinary incontinence subsequent to surgery, almost never occurs.  I personally prefer to use this surgery as a treatment of last resort (I believe that most cases of feline urinary tract obstruction can be treated medically).  The strongest indication for PU in my mind is repeat urinary obstruction, despite appropriate medical management and not due to cystic and urethral calculi.

The longitudinal incision made in the dorsal urethra, needs to be brought to a level just cranial to the bulbourethral glands.  To achieve this, the ischiocavernosus muscles must be dissected off of the ischii and the urethra must be dissected well into the pelvic canal.  If the urethral incision isn't carried to this level, the resulting stoma will be too small and insufficiently distensible to accomplish the original goal of the PU.  Also, when suturing the urethra to the perineal skin, there must be good epithelial to epithelial contact all around the stoma.  If there are gaps present, granulation tissue will develop, the wound will heal in part by contraction and epithelialization, and there will be a much higher chance of stricture formation.

This surgery can be more difficult in very fat cats because it is difficult to bring the urethra out to skin level without tension (the PU is still functional, but it tends to result in a "sucked in" appearance).  Perineal urethrostomy performed as an emergency procedure can also be a bit more risky because there is usually significant urethral inflammation that can affect wound

healing.  I have found some of these urethras to be very friable and have poor suture holding strength.  In these cases (where dehiscence or stricture formation is a serious concern), I usually will convert the perineal urethrostomy to an antepubic urethrostomy.  This involves a caudal abdominal laparotomy to allow retrieval of the pelvic urethra.  If this cannot be sufficiently isolated through the perineal approach, a pubic osteotomy is performed to facilitate dissection and elevation of as much urethra as possible.  The urethra is brought through the body wall incision to the level of the skin.  If a pubic osteotomy were performed, it is reduced and stabilized with cerclage wire.  The body wall is closed except for the caudal one cm or so (so the urethra can pass through this portion without excessive compression).  The end of the urethra is spatulated and sutured like a perineal urethrostomy to the skin at the caudal end of the incision or to a separate incision caudal to the main laparotomy incision if the length of urethra permits.  The main problem that I have seen with antepubic urethrostomy is urine scald around the pendulous inguinal skin folds seen in fat cats.  Most cats, though, respond very well to this procedure and maintain full continence.

If you have any questions about these conditions, or any other surgical condition, please feel free to call any of the surgeons here at SouthPaws (Bud Siemering, Dan Brehm, and Eileen Snakard) at 703-451-0909.  We have a full range of advanced diagnostic and therapeutic equipment -- and extensive experience -- to treat a very wide range of soft tissue, oncologic, orthopaedic, and neurosurgical disorders.  All referring veterinarians and technicians are welcome to visit SouthPaws and scrub in on any surgeries in which they are interested.

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dog is hiding it is likely in a confined space, so it is also cornered. The owner pulling it out adds to its fear, and the dog might perceive the owner as threatening and the dog reacts to defend itself from the threat.
Another medication used for thunderstorms is diazepam.  This tends to be a bit more sedating than alprazolam. I do not use acepromazine for thunderstorms because it is not an anxiolytic, a dog is less responsive to the storm but is just as anxious about it.

I have not used melatonin for thunderstorms, however a dose that I found is dogs less than 5kg .5-1 mg, 5-15 kg 1.5 mg, 15-50 kg 3 mg; it can be given up to three times a day. Plain tablets only not capsules or other forms.