Urinary Stress Incontinence

Question 1

What is urinary stress incontinence?

Answer 1

Involuntary leakage of urine on effort or exertion, or on sneezing or coughing

Question 2

How can a diagnosis be made definitively?

Answer 2

Urodynamic studies

Excluding an overactive bladder using cystometry

Question 3

How many female incontinence cases are caused by USI?

Answer 3

50%

Question 4

Percentage of women affected by USI?

Answer 4

More than 10%

Question 5

Causes of USI?

Answer 5

Pregnancy and vaginal delivery (particularly prolonged labour and forceps delivery)
Obesity
Age (post-menopausal)
Previous hysterectomy (not for prolapse or urinary Sx) may predispose to USI

Question 6

Relationship between prolapse and USI?

Answer 6

Prolapse commonly coexists but may be unrelated

Question 7

Mechanism of incontinence?

Answer 7

When there is an increase in intra-abdominal pressure (‘stress’), the bladder is compressed and its pressure rises

In normal women, the bladder neck is equally compressed so that the pressure difference is unchanged

However, if the bladder neck has slipped below the pelvic floor because its supports are weak, it will not be compressed and its pressure remains unchanged. If the rest of the urethra and the pelvic floor are unable to compensate, the bladder pressure exceeds urethral pressure and incontinence occurs

Question 8

Clinical Fx in Hx?

Answer 8

Assess degree to which pt’s life is disrupted

Stress incontinence predominates but many patients complain of frequency, urgency or urge incontinence. Must prioritise Sx as Tx for USI differs from overactive bladder.

Faecal incontinence , also from childbirth injury, may coexist

Question 9

Clinical Fx in examination?

Answer 9

Sims speculum exam often (but not always) reveals a cystocele (bladder prolapse into vagina) or urethrocele (urethra prolapse into vagina)

Leakage of urine on coughing

Abdomen palpated to exclude distended bladder

Question 10

Ix in USI?

Answer 10

Urine dips to exclude infection

Cystometry to exclude OAB if surgery is considered o if OAB Sx fail to respond to medical Tx

Question 11

Lifestyle changes to manage USI?

Answer 11

Obese = lose weight
Address cause of chronic cough (e.g. smoking)
Reduce excessive fluid intake

Question 12

Aims of conservative Tx?

Answer 12

Aimed at strengthening the pelvic floor

Question 13

1st line conservative Tx of USI?

Answer 13

Pelvic floor muscle training (PFMT) for at least 3 months and taught by physiotherapist
Strength of pelvic floor muscle contraction should be digitally assessed before Tx
PFMT should consist of at least 8 contractions, 3 times per day
PFMT beneficial = continue exercise programme

Question 14

2nd line conservative Tx of USI?

Answer 14

Vaginal ‘cones’ or sponges alleviate incontinence in more than half of patients
‘Cones’ (look like round balls) are inserted into the vagina and held in place by voluntary muscle contraction
Increasing sizes are used as muscle strength increases

Question 15

Only drug licenced to Tx moderate to severe USI?

Answer 15

Duloxetine

Question 16

How does duloxetine work?

Answer 16

Serotonin and noradrenaline uptake inhibitor (SNRI)

Enhances urethral striated sphincter activity via a centrally mediated pathway

Question 17

Side effects of duloxetine?

Answer 17

Nausea
Dyspepsia (indigestion)
Dry mouth
Dizziness
Insomnia
Drowsiness

Question 18

When is surgery considered?

Answer 18

Conservative measures failed and woman’s QOL compromised

Question 19

1st line surgical Tx?

Answer 19

Tension-free vaginal tape (TVT)
Transobturator tape (TOT)

Gold standard of Tx

Question 20

Risks of TVT or TOT

Answer 20

Bladder perforation
Postoperative voiding difficulty
Bleeding
Infection
De novo detrusor overactivity
Suture or mesh erosion

Question 21

Success rates of TVT or TOT

Answer 21

Up to 90%

Question 22

Other surgical Tx besides TVT or TOT?

Answer 22

Injectable periurethral bulking agents (lower success rates but good for those not yet completed childbirth, frail elderly and if previous surgery failed)

Question 23

Difference between USI and stress incontinence?

Answer 23

USI = Disorder diagnosed only after cystometry, of which stress incontinence is the major Sx

Stress incontinence = Sx; “I leak when I cough”. Can be due to USI but may also be result of overactive bladder or overflow incontinence