Technique for urethral
catheterization of the male domestic ferret (Mustela putoris furo)
Cheryl B. Greenacre
Department of Small Animal Medicine, College of Veterinary Medicine, University of
Georgia, Athens, GA 30602
Abstract: An
increasing number of ferrets in the United States present for acute stranguria due to a
variety of causes. Veterinarians may encounter difficulties in placing a urethral catheter
in ferrets due to the small size of the patient, lack of appropriate equipment or
unfamiliarity with the anatomy of the ferret urethra and associated structures. The
following is a description of a procedure utilized to place a urethral catheter in a
ferret including a video.
Key Words: Ferret, Mustela putoris
furo, Urinary tract, Stranguria, Male, Catheterization
| Note:
Treatment of animals should only be performed by a licensed veterinarian.
Veterinarians should consult the current literature and current pharmacological
formularies before initiating any treatment protocol. |
Introduction
The most common cause of stranguria in a
ferret is prostatic hyperplasia, cysts or abcesses secondary to hormonal influence from a
diseased adrenal gland, even if the ferret has been previously neutered. Neoplasia of the
adrenal gland in domestic ferrets in the United States is common and is usually due to
adrenal hyperplasia, adenoma or adenocarcinoma.1-5 The next most common cause
of stranguria in the ferret is urolithiasis (usually struvite) of any size including a
syndrome similar to cats with stones the size of a grain of sand.3 All other causes of
stranguria that occur in dogs and cats can also occur in ferrets including neoplasia of
the urinary tract.
The prepuce is ventral in ferrets much
like it is in dogs. Unlike dogs though, the os penis of the ferret is curved at the distal
tip and extends approximately 4 mm beyond the pink urethral tissue.6,7 Therefore, the urethral orifice is not at the tip of the penis, but at the pink penile
tissue, white os penis juncture, on the ventral surface, approximately 4 mm proximal from
the tip of the os penis. Due to the curved, bony tip, exposure of the penis is difficult
and uncomfortable for the ferret. Therefore, it is recommended the ferret be anesthetized
for urethral catheterization. Isoflurane is the anesthetic of choice. To facilitate
visualization and insertion of the catheter, the urethral orifice is delicately lifted
open with a small instrument (such as a 25 gauge needle, bevel down). A pair of magnifying
loupes is greatly helpful in visualizing the urethral opening and is recommended.
The procedure for placing a urethral
catheter in a ferret is much the same as in a dog, except that the catheter should be
3-1/2 French in size.8 If a 3-1/2 French red rubber catheter cannot be passed,
then a 22 gauge jugular catheter may be attempted, but care must be taken not to damage
delicate tissues with this more rigid catheter. The stylet is removed after placement. To
pre-measure the catheter it should extend from the prepucial opening to the pubis and back
again, minus approximately 2 cm.
Once a urethral catheter is placed with
its tip approximately 1 cm into the bladder, it is sutured to the skin near the prepuce
and taped along the dorsum and at the base of the tail. All exposed rubber must be covered
with self adhesive wrap or tape since ferrets are predisposed to chewing rubber products.
| Step by Step Procedure | Play Video >> |
| 1. |
Preferably the
ferret should have an empty stomach prior to being anesthetized. Since the gastric
emptying time of a ferret is 2 hours, the ferret should have food withheld at least that
long. |
| 2. |
Anesthetize
the ferret with isoflurane gas anesthesia. |
| 3. |
After
pre-measuring the catheter, have an assistant expose the penis while you aseptically
prepare the penis and adjacent preputial tissue with chlorhexadine surgical scrub and
rinse with sterile saline. Repeat scrub and rinse 3 times. |
| 4. |
While wearing
sterile gloves, gently roll the shaft of a sterile 25 gauge needle on the ventral surface
of the penis where the pink penile tissue and white os penis meet to identify the urethral
orifice. |
| 5. |
Once the
urethral orifice has been visualized , utilize the tip of the sterile 25 gauge needle,
bevel down to prevent inadvertently cutting the urethral tissue, to lift it open. Then
thread the 3-1/2 French red rubber catheter into the opened urethral orifice. Difficulty
will be experienced curving around the pubis. Placement of the catheter can be checked
with radiographs. |
| 6. |
Once in place,
the exposed part of the catheter is curved dorsally to rest along the dorsum and the
dorsal surface of the base of the tail. The catheter is sutured to the skin near the
prepuce, and taped to the body. Tape is often placed completely around the body of the
ferret and around the base of the tail. |
| 7. |
A syringe or
bag is then placed on the exposed end of the catheter, taking care to cover all exposed
rubber parts with self-adhesive wrap. |
| 8. |
Correct
underlying disease cause.
|
References
1. Coleman GD,
Chavez MA, Williams BH. Cystic prostatic disease associated with adrenocortical lesions in
the ferret (Mustela putoris furo). Vet Pathol, 35:547-549, 1998.
2. Rosenthal KL,
Peterson ME. Stranguria in a castrated male ferret. J Amer Vet Med Assoc, 209:62-64, 1996.
3. Hillyer EV.
Urogenital diseases. In: Ferrets, rabbits and rodents - Clinical medicine and
surgery, Hillyer EV, Quesenberry KE (eds.), Saunders, Philadelphia, 44-52, 1997.
4. Rosenthal KL.
Endocrine diseases, part II. In: Ferrets, rabbits and rodents - Clinical medicine
and surgery, Hillyer EV, Quesenberry KE (eds.), Saunders, Philadelphia, 91-98, 1997.
5. Fox JG, Marini
RP. Diseases of the endocrine system. In: Biology and diseases of the ferret, 2nd
ed., Fox JG, (ed.), Williams and Wilkins, Baltimore, 291-306, 1998.
6. Brown SA.
Basic anatomy, physiology, and husbandry. In: Ferrets, rabbits and rodents -
Clinical medicine and surgery, Hillyer EV, Quesenberry KE (eds.), Saunders, Philadelphia,
3-13, 1997.
7. Quesenberry
KE. Basic approach to veterinary care. In: Ferrets, rabbits and rodents -
Clinical medicine and surgery, Hillyer EV, Quesenberry KE (eds.), Saunders, Philadelphia,
14-25, 1997.
8. Marini RP,
Esteves MI, Fox JG. A technique for catheterization of the urinary bladder in the ferret.
Lab Animal 28:155-157, 1994.
This Page Last Updated November 15, 1999 |