Sa Medicine Ii -- Urinary Incontinence

-- leaking urine

-- inc. in frequency

-- unfruitful efforts to urinate

-- external sphincter

-- internal sphincter

-- storage phase

>> sympathetic input to sphincters >> closed

-- voiding phase

>> parasympathetic input

>> detrusor m. contracts

>> sphincters relax

-- normal bladder innervation and sensation

>> can detect that it's full

-- likely obstructed

-- innervation problem

-- partial function

-- obstruction

-- sphincter dysfunction

-- hyperfunction

>> hypersensitivity of the bladder

>> inflammation most common cause

>> infection in dogs, idiopathic cystitis in cats

-- weak sphincter

-- anatomical defect

-- paradoxical (obstructive) incontinence

-- sphincter timing problem

-- obstruction

Upper motor neuron bladder

-- detrusor areflexia (atonic bladder)

-- sphincter hypertonus

>> no attempt to void

>> no voiding

>> lg. amount residual urine

>> difficult to express

Lower Motor Neuron Bladder

-- detrusor areflexia + sphincter areflexia

>> no attempt to void

>> no voiding (may leak)

>> large to moderate amount residual urine

>> easy to express

-- decreased sphincter tone

>> voiding normal
(leakage with stress, full bladder)

>> no residual urine

>> easy to express

>> perineal reflex may be absent

-- leaking when bladder is full

-- sphincter incompetence

>> urethral sphincter mechanism incompetence

>> UTI

>> pudendal lesion

-- anatomical defects
>> sphincter by-pass: ctopic ureters

-- one or both ureters bypass the sphincter

-- normal urination

-- constant leaking

-- leaking during stress

-- important Ddx in young animals

-- intravenous pyelogram w/ CT

-- cystoscopy

-- CT

-- surgery

-- laser ablation

-- urethral sphincter mechanism incompetence

-- UTI

-- pudendal lesion

-- middle-aged, spayed females

-- incontinence with full bladder

>> leak at night or when relaxed

>> hours after voiding

>> can be precipitated by PU/PD

-- history and clinical signs

-- rule out UTI
-- urethral pressure profile

-- phenylpropanolamine, BID or TID

>> watch for hypertension

-- dethylestilbestrol (DES)

>> watch for bone marrow suppression)

-- imipramine

>> use in conjunction with other drugs

-- monitor CBC

-- don't ignore any cytopenia in dogs on DES

>> starts with neutropenia (stop drug now!)

>> second, lose platelets

>> third, lose RBCs (too late!)

-- colosuspension (pull bladder forward, stretch urethra)

-- cystourethropexy

-- bladder or urethral slings

-- periurethral collagen injection

-- hydraulic occluder

-- inflammation of urinary bladder

-- UTI and stones

-- sensation of fullness at low volumes

-- urgency

-- propantheline

-- oxybutynin

-- RO inflammation, infection, stone

-- stones in male dogs

-- reflex dyssnergia

>> bladder and sphincters are not coordinated

-- obstruction causes leaking with full bladder

>> treat underlying problem

>> urethral stones

>> prostatitis, urethritis, neoplasia (TCC)

-- empty bladder >> anatomical defect

-- full bladder >> paradoxical (obstruction) or detrusor arreflexia

-- normal or inc. sphincter tone (UMN bladder)

-- decreased sphincter tone (LMN bladder)

-- overdistention

>> should have other neuro signs, like paresis

-- separation of tight junctions causes atony

>> can also be caused by inflammation, edema

>> act immediately to prevent permanent damage!

>> avoid manual expression

-- keep bladder empty for 7 days

>> place urinary catheter

>> allow tight junctions to be repaired

-- bethanecol to inc. contractility

-- ectopic ureters

-- USMI, UTI

-- UTI

--paradoxical incontinence

-- can lead to atonic bladder