Urinary incontinence

Question 1

Describe how to bladder fills

Answer 1

The sympathetic nervous system predominates–> inhibition of detrusor muscle allows passive filling of the bladder- sympathetic nervous system also contracts the internal urethral sphincter

Question 2

what is the micturition reflex

Answer 2

detrusor reflex and inhibition of sympathetic and somatic stimulation to bladder and ureters

Question 3

describe how urination occurs

Answer 3

The parasympathetic nervous system dominates
When threshold is reached, stretch receptors in the bladder wall stimulate detrusor muscle contraction = detrusor reflex
Urethral sphincter muscles relax

Question 4

define true urinary incontinence

Answer 4

the patient is unaware that they are leaking urine. Usually due to poor sphincter functionality (uncommon in cats)

Question 5

define urge incontinence

Answer 5

the patient is aware that they need to urinate but may have lack of control. Can be caused by bladder irritation or seen as inappropriate urination

Question 6

define overflow incontinence

Answer 6

the patient is (usually) unaware that they are urinating, occurs when urine pressure within the bladder is greater than the urethra. Considered a ‘voiding’ rather than storage disorder

Question 7

describe somatic nervous control of the bladder

Answer 7

The somatic nervous system (voluntary):
Stimulates urethral striated muscle contraction (for sudden or prolonged increases in bladder pressure)

Question 8

what other signs may you see with neurogenic incontinence

Answer 8

LMN signs
paralysis

Question 9

what are non-neurogenic incontinence

Answer 9

anatomical or functional disorders of the urinary tract

Question 10

what are the 2 broad categories of incontinence

Answer 10

neurogenic and non-neurogenic

Question 11

if there is a cerebral lesions what will it present with regarding the bladder

Answer 11

Causes rare, loss of voluntary control
The bladder can empty normally but often at inappropriate times

Question 12

List 4 things that are seen with brainstem-L7 lesions what will it present with regarding the bladder

Answer 12

• Bladder is hard to express
• Increased urethral sphincter tone
• High volume urinary retention
• Development of automatic bladder*

Question 13

List 6 things that are seen with S1-S3 or nerve root lesion what will it present with regarding the bladder

Answer 13

Absent voluntary micturition
Bladder is atonic, flaccid and easy to express
Concurrent reduced perineal reflex and anal tone, may have tail paralysis
Atonic urethral sphincters
Absent detrusor reflex
Can result in overflow incontinence when full

Question 14

what is the most common presentation of Urethral Sphincter Mechanism Incompetence (USMI)

Answer 14

female
spayed
older
large breed
overweight

Question 15

what is the most common non-neurogenic cause of canine incontinence

Answer 15

Urethral Sphincter Mechanism Incompetence (USMI)

Question 16

how do Urethral Sphincter Mechanism Incompetence (USMI) presents

Answer 16

as intermittent involuntary leaking of urine when dog is relaxed (sleeping) or excited
Patient may have good/bad leaking days

Question 17

List the 2 problems that are occurring in Urethral Sphincter Mechanism Incompetence (USMI) that we can try and medically manage

Answer 17

low urethral tone/ reduce amount of smooth muscle in urethra
hormonal influence (aging or lack of oestrogens change urethral structure)

Question 18

Describe how we medically manage low urethral tone/ reduce amount of smooth muscle in urethra in USMI

Answer 18

sympathomimetic agents= aim to mimic the storage of urine phase - e.g. phenylpropanolamine

Question 19

Describe how we medically manage hormonal influence of USMI

Answer 19

give oestrogens (only neutered bitches) = acts on oestrogen receptors in sphincters e.g. incurin

Question 20

what happens with ectopic ureters

Answer 20

Incontinence observed shortly after birth
Bladder is bypassed and urine may empty into vagina or urethra

Question 21

describe how to treat an ectopic ureter

Answer 21

surgical

Question 22

describe detrusor instability

Answer 22

an overactive bladder presenting as pollakiruria. Most animals have underlying cystitis, irritating the bladder lining and over stimulating the detrusor reflex. = URGE INCONTINENCE

Question 23

list the 2 reasons that urinary retenttion occur

Answer 23

detrusor muscle isn’t working well
OR
bladder is contracting against high outflow pressure

Question 24

what do we tend to see with urinary retention

Answer 24

stranguria or dysuria, and may be attempting to void urine but be unsuccessful.

Question 25

describe how to manage urine retention issues

Answer 25

Facilitate bladder emptying
Medicate depending on cause

Question 26

List 4 possible causes of neurogenic urinary retention

Answer 26

LMN disorder
UMN disorder
Detrusor-urethral dyssynergia
Dysautonomia- RARE- would have other neuo signs as well

Question 27

List 3 possible causes of non-neurogenic retention

Answer 27

blockage
Trauma to ureters and/or bladder
Detrusor atony

Question 28

describe detrusor atony

Answer 28

Often from over distention of bladder; secondary condition we want to avoid
Bladder distended and flaccid

Question 29

Describe how to manage Lower Motor Neuron (LMN) disorders that affect the bladder

Answer 29

Bethanecol (a parasympathomimetic) may improve bladder contractility IF there is some function left
Nursing/home care: manual expression 3-4 x daily, cleaning, monitoring for UTi

Question 30

Describe what can happen with upper motor neuron disorders

Answer 30

Disruption between the sacral segments and the pontine micturition centre in the brain
——> reflex detrusor contraction (trying to empty bladder)
—–> concurrent uninhibited sphincter spasticity (hard to empty past this)

Question 31

Describe how to treat UMN disorders that are affecting the bladder

Answer 31

urethral smooth muscle relaxants
skeletal muscle relaxants
monitoring for UTI is important

Question 32

what is Idiopathic reflex dyssynergia

Answer 32

Loss of coordination between the detrusor muscle contracting, and the relaxation of the urethra. (they are not working coordinated)
Presents a spurting urine flow

Question 33

describe how to treat Idiopathic reflex dyssynergia

Answer 33

short term- treat underlying cause and prevent over distention
Help restore normal detrusor contraction (parasympathomimetic agents)
May improve spontaneously or require medication long-term

Question 34

what is the most common dogs affected by Idiopathic reflex dyssynergia

Answer 34

male dog
large breed