Gab Kovacs1 and Paula Briggs2
(1)
Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
(2)
Sexual and Reproductive Health, Southport and Ormskirk Hospital, Southport, UK
Incontinence
Definition
Incidence
Aetilogy and Pathogenesis
Clinical Assessment
Investigations
Treatment
Complications
Prognosis
Recurrent Urinary Tract Infections
Incontinence
Definition
Incontinence is the involuntary loss of urine. It is divided into:
· Stress incontinence – The involuntary loss of urine in association with raised intra-abdominal pressure, e.g. on coughing, sneezing, jumping, running etc.
· Urge incontinence – The need to pass urine with little warning and occasional accidents. This is often associated with urinary frequency and having to pass urine at night (nocturia). Women with urgency will often “toilet map”. They also leak in specific situations e.g. putting the key in the lock of the front door or turning on the tap.
· Mixed incontinence – This is when both stress and urge incontinence co-exist and this is not uncommon (Fig. 10.1).
Fig. 10.1
Types of incontinence
· Asking simple questions can determine whether a woman has stress, urge or mixed incontinence.
· Persistent incontinence- This occurs if there is a fistula of the urethra or the bladder with a constant leak of urine.
· Incontinence with overflow – This is when there is a neurological or mechanical obstruction of the bladder, with the bladder over-distending and then leaking due to a build up of pressure.
Incidence
Approximately half of postmenopausal women report urogenital symptoms. These generally appear soon after the menopause transition and worsen with time.
Aetilogy and Pathogenesis
The aetiological shopping list is less appropriate for these symptoms. Oestrogens have a significant physiological effect on the genitourinary tract, with receptors in the bladder and urethra. Oestrogen can also affect the neurology of micturition on a central and peripheral level, by influencing the autonomic nervous system. Oestrogen affects collagen metabolism in the lower genitourinary tract. Progesterone generally adversely affects female urinary tract function, typically decreasing the tone in the ureters, bladder and urethra. This may be the reason why urinary symptoms worsen during the secretory phase of the menstrual cycle, and during pregnancy.
Stress Incontinence
The primary problem here is that the proximal urethra becomes extra-abdominal (Fig. 10.2). Whilst the proximal urethra is within the abdominal cavity, any increase in abdominal pressure, acting on the bladder will be neutralised by pressure on the proximal urethra. Once the proximal urethra is extra abdominal, there is no neutralisation, and consequently there is a pressure gradient along the urethra, and urine escapes.
Fig. 10.2
Pathogens is if stress incontinence
· Urge incontinence – at birth, there is a simple reflex arc through the spinal cord, so that as soon as the bladder distends, it empties.. As supratentorial influences develop, this reflex is inhibited, resulting in continence. With advancing age and lack of oestrogen, this reflex tends to want to take over again, requiring the bladder to be emptied more frequently and urgently.
· Persistent incontinence as a result of a fistula is obvious and urine leaks continuously. Most fistulas are due to iatrogenic surgical complications, or occasionally due to an obstetric injury.
· Incontinence with overflow – This is associated with a neurogenic bladder, where the efferent arm of the reflex arc is malfunctioning, and the bladder cannot empty.
Clinical Assessment
History
The duration of the symptoms needs to be ascertained, together with any possible precipitating factor.
· The frequency of micturition during the day and the night should be documented.
Is there a history of incontinence associated with an increase in intra-abdominal pressure?
Enquire about the degree of urgency, accidents, and possible incomplete bladder emptying.
· Symptoms of urinary tract infection- frequency and dysuria?
Examination
· Abdominal examination should always precede vaginal examination in case there is an abdominal or pelvic mass displacing the pelvic organs.
Speculum examination is usually carried out in the dorsal position.
The presence of stress incontinence can be diagnosed by asking the patient with a full bladder to cough.
· Bimanual examination- A routine bimanual examination should be undertaken, assessing the size of the uterus, its mobility, and the presence of any pelvic masses e.g. ovarian cysts.
Investigations
· Urinalysis using a dip stick can be undertaken at the time of the initial presentation and urine microscopy and culture
· arranged if there is suspicion of a urinary tract infection.
· Urodynamic studies – these are “volume: pressure” measurements of the bladder. The pattern of contractions can differentiate between genuine stress incontinence and urge incontinence. If there are doubts on clinical history, a urodynamic assessment should be performed. Prior to incontinence surgery a urodynamic assessment should be undertaken.
Treatment
Conservative
· Weight loss,
· Fluid management e.g. not drinking before bedtime.
· Avoidance of diuretics such as tea, coffee and alcohol.
· Bladder re-training including timed voiding. This requires keeping a diary of the time of each voiding, and the measurement of the urine volume passed. This teaches the woman that her bladder does not have to be emptied when there is only a small volume of urine present.
· Treatment of a chronic cough or constipation has been shown to be of benefit in patients with urinary incontinence.
· Pelvic floor exercises can benefit bladder control.
Stress incontinence (SUI) and Urge Incontinence (UUI) are managed differently.
SUI does not respond to drug therapy. Use of a ring pessary with a knob, which alters the angle of the junction between the bladder and the urethra, may be helpful, but surgery is the mainstay of treatment.
Hormonal
HRT is unlikely to help with SUI
· It may have some effect in some women with UUI
· It will have no effect on fistula, or retention with overflow.
Other Medical
UUI can be managed successfully using antimuscarinic drugs, These drugs reduce detrusor muscle contraction and increase bladder capacity. Contraindications to their use include having a history of acute angle closure glaucoma and cardiac arrhythmias.
There are different options ranging from drugs such as oxybutynin, which is inexpensive, but often associated with intolerable side effects (most frequently dry mouth, gastrointestinal disturbance, blurred vision, dizziness, drowsiness, difficulty voiding, palpitations/arrhythmias and skin reactions) to newer more expensive drugs, which result in less side effects.
The use of an oxybutynin slow release patch is a useful option for women who have side effects with any of the oral preparations. The most recent addition to the range of treatments available is a selective beta 3-adrenoceptor agonist. It has a different mode of action to the antimuscarinic agents, relaxing the smooth muscle in the bladder and enhancing urine storage and is unlikely to interfere with the urine voiding phase as it is predominantly the activity of acetylcholine on the muscarinic receptors that induces bladder contraction. This is a good drug to use for women who are unable to tolerate the side effects of any of the antimuscarinic agents.
Patients with refractory overactive bladder can be treated with sacral neuro-modulation. This can provide effective relief of overactive bladder symptoms and also neurogenic retention.
Another, non surgical treatment is percutaneous tibial nerve stimulation.
Surgical
Minor – Cystoscopically directed intravesicular (into the detrusor muscles) injection of Botulinum toxin is an option to treat overactive bladder. Women need to be aware of the risk of urinary retention and the need for repeated injections every 6–9 months.
For women with urodynamically proven stress urinary incontinence with a stable bladder, synthetic mid-urethral slings form the mainstay of treatment. This is a minimally invasive procedure, and the sling can be placed via a retropubic, trans-obturator or minimally invasive ‘inside-out’ mini-sling approach. Success rates are comparable with all these modalities, however for patients with ‘intrinsic sphincter deficiency’ the retropubic approach remains the gold standard.
Women with SUI in whom mid-urethral slings have either been ineffective, or are only partly effective, may be suitable for treatment with urethral bulking injections. These are also appropriate for elderly women, women who cannot undergo surgery, those who require continued anticoagulation therapy or have poor bladder emptying. These act by improving urethral mucosal co-aptation and restoring the mucosal seal mechanism of continence.
Complications
Urinary incontinence can be very embarrassing and in some cases socially isolating.
Prognosis
Urinary problems may get worse with time.
Recurrent Urinary Tract Infections
Whilst this is not really a gynaecological problem, UTIs can be a cause of incontinence and diagnosis and treatment may prevent unnecessary surgery. If diagnosed, a predisposing cause should be looked for, and prophylactic antimicrobial treatment can be instituted.