Renal - Urinary Incontinence Flashcards
What is dysuria?
painful urination
What is stranguria?
slow/strained urination
What is pollakiuria?
Frequent urination of small amounts
What is polyuria?
urination of large amounts
What is incontinence?
involuntary (unconscious) release of urine through the urethra
What is incontinence associated with (like behaviorsish)?
A wet bed, licking penis/vulva, dribbling urine while walking
What behaviour is associated with polyuria?
positions itself in a micturition position - increased volume of urine is associated
What are the general components of micturition?
nerves and muscles
What nerves are involved with micturition?
Hypogastric, pelvic, and pudendal
What muscles are involved with micturition?
Detrusor, interrnal urethral sphincter, and external urethral sphincter
What are the two phases of micturition?
Filling and voiding
Filling is associated with parasympathetic/sympathetic control under the control of norepinephrine/acetylcholine.
Sympathetic, norepinephrine
Voiding is associated with parasympathetic/sympathetic control under the control of norepinephrine/acetylcholine.
Parasympathetic, acetylcholine
What are the three broad mechanisms of urinary incontinence?
Failure of bladder to sufficiently accommodate urine
Abnormal anatomy of ureteral termination, urinary bladder or urethral development
Failure of sufficiently functional urethral closure
Define destrusor instability.
Involuntary bladder contractions at low bladder volumes
What populations should you consider that detrusor instability is the cause of incontinence?
Incontinent dogs refractory to standard therapy
ectopic ureter patients
How is detrusor instability treated?
Enhance bladder relaxation
How do you enhance bladder relaxation?
Anticholinergics (counter the pelvic nerve from contracting the bladder)- Oxybutinin and dicyclomine
Tricyclic antidepressants
What is/are ectopic ureters?
incorrect termination of one or both ureters
Where are ureters normally located?
Dorsolateral insertion with short tunneling prior to termination in trigone
What are the different forms of ectopic ureters? Define.
intramural - penetrates serosa at the correct spot but then tunnels and opens in a different spot of the bladder
extramural - open in urethral
Do males or females typically get ectopic ureters more commonly?
Females - they also present earlier
What are the breed predisposition for ectopic ureters?
Siberian Husky, labrador retriever, golden retriever, newfoundland, english bulldog, westies
True or False: Most cases of ectopic ureters are bilateral.
True
Is intramural or extramural ectopic ureters more common?
intramulal
Where is the most common termination of ectopic ureters?
the urethra
What abnormalities are associated with ectopic ureters?
UTIs, hydroureter, hydronephrosis/pyelectasia, and vestibulovaginal septal remnants
How are ectopic ureters diagnosed? What is the gold standard?
Contrast cystourethrogram
US
CT
Cystoscopy - Gold standard
How are extramural ectopic ureters treated?
Neoureterocystostomy - reimplantation in correct location in the bladder
How are intramural ectopic ureters treated?
Neoureterotomy and cytoscopic-guided laser ablation
What is the outcome postop of surgical ectopic ureter correction?
37-74% are continent post op
What is the outcome postop of cystoscopic laser ablation?
Ablation alone has continence rates of 31-57%
Ablation with other treatment has continence rates of 38-77%
Are complications more commonly associated with surgery or laser ablation?
surgery
What are common ectopic ureter correction complications?
Uroabdomen, ureteral stenosis, hydroureter/nephrosis
What are some minor complications associated with ectopic ureter correction?
hematuria and dysuria
What is urethral sphincter mechanism incompetence (USMI)?
Weak urethral pressure resulting in incontinence
Note: it is the most common cause of incontinence in dogs and also known as ‘spay incontinence’
What are the proposed mechanisms of USMI?
Adhesion between the bladder neck and uterine stump
Anatomical/neural damage
Changes secondary to hormonal alterations
Caudal (pelvic) positioning in the bladder
What is the epidemiology of USMI?
Seen in 5-20% of spayed female dogs
Young/middle aged large-breed dogs
Breeds: GSH, dobermans, boxers, and rottweilers
At what age of spay is there an increased risk of USMI?
<3 months
What is the gold standard of treatment for USMI?
Urethral pressure profilometry
Must exclude other causes of incontinence
What are the general treatment options to USMI?
medical, endoscopic, and surgical
What are the medical treatment options to USMI?
Alpha-agonists, estrogen analogues, and testosterone cypionate
What is the endoscopic USMI treatment option?
Collagen injection
What are the surgical USMI treatment options?
Colposuspension, cystourethropexy, and urethral hydraulic occluder
What is the main alpha-agonist we use for treatment of USMI?
Phenylpropanolamine (PPA)
What is the MOA of PPA?
Direct stimulation of urethral alpha 1 adrenergic receptors
What are the adverse effects of PPA?
CV effects - hypertension, tachycardia, and excitement
What other alpha agonists can be used to treat USMI?
Ephedrine and pseudoephedrine
Why is PPA better than ephedrine and pseudoephedrine?
It is more effective and has less side effects
What is the MOA of estrogens in medical therapy of USMI?
Increased sensitivity of alpha receptors of the urethra
Hypertrophy of urethral epithelium
Improved urethral vascularity
What are the adverse effects of using estrogens to treat USMI?
Reproductive (estrus, male attraction) alopecia, bone marrow suppression
What estrogen can be used with USMI?
Diethylstilbesterol and Estriol (FDA approved and more effective)
What do urethral collagen injections do?
Endoscopic bulking of the proximal urethra with SQ collagen injections
How long do collagen injections work?
17-21 months - will need repeated procedures
What is colposuspension?
Where the vagina is affixed to the prepubic tendon to lengthen and compress the urethra
Good short term
What is a cystourethropexy?
Anchoring of urethra to the ventral abdominal wall
What does an inflatable urethral occluder do?
Increases the urethral tone
