Urinary Incontinence and Bladder Problems in Dogs (cont.)
Spinal cord injuries, infections, tumors, and inherited neuropathies can interfere with the nerves that control the bladder. A bladder with a compromised nerve supply lacks muscle tone and cannot contract. The bladder continues to fill until the pressure exceeds the resistance of the sphincter mechanism that closes the urethra. This results in intermittent, uncontrolled dribbling.
Neurogenic incontinence can be confirmed with a cystometrogram. This is a test that measures how forcefully the bladder contracts in response to the introduction of incremental volumes of fluid into it through a catheter. The results also suggest the site of the neurologic deficit (the spinal cord or the bladder).
Treatment: Neurogenic incontinence is treated with long-term catheterization and antibiotics to treat and suppress infection. Drugs that act on the bladder may be of help. This type of incontinence is difficult to treat. The problem may totally resolve, however, in dogs whose spinal cord injuries have been successfully treated.
Incontinence from Overdistension of the Bladder
This type of incontinence is due to a partially obstructed bladder, caused by urethral stones, tumor, or stricture. The signs and symptoms are similar to those of neurogenic incontinence, but the nerve supply to the bladder is undamaged.
Treatment: Dribbling associated with an overdistended bladder is treated by correcting the cause of the obstruction and placing an indwelling catheter until the bladder regains its muscular tone. Drug therapy is also beneficial. Since the bladder is neurologically normal, treatment may eliminate the problem entirely.
This article is excerpted from “Dog Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.
Copyright © 2007 by Howell Book House. All rights reserved.