Abstract
Stress urinary incontinence (SUI) is a prevalent condition, affecting a significant proportion of women, with 13.6% requiring surgical intervention during their lifetime. Surgical treatments primarily aim to provide suburethral support or enhance urethral closure mechanisms. Traditionally, colposuspensions and autologous rectus fascial slings have been considered effective first-line surgical options for managing SUI. These procedures have shown reliable outcomes in terms of symptom relief and long-term efficacy. The use of midurethral tapes, once the most popular treatment option in the UK, is currently suspended due to the concerns about the risk of chronic pelvic pain and vaginal mesh exposure. It remains an option for women with deemed ‘exceptional circumstances’ and may be cautiously reintroduced into practice with certain prerequisites. The mesh ‘pause’ has driven a much-improved process of patient counselling, expectation setting, utilizsation of the ‘MDT’, enhanced surgical standards and data collection. It has led to a reassessment of surgical approaches. The current trend is for many women to request intra-urethral bulking (Bladder neck injection) as a first line procedure to treat primary SUI. There is a renewed focus on established methods like colposuspension, open or laparoscopic, and modified autologous fascial ‘sling on a string’. These procedures avoid mesh related risks but are associated with different risks such as new onset vaginal prolapse and post-operative voiding difficulty, respectively.
Introduction
Stress urinary incontinence (SUI) describes the symptom of involuntary leakage of urine on effort or exertion, or on sneezing or coughing, as defined in the joint International Continence Society/International Urogynaecological Association standardization document. Its prevalence in Europe is reported to be 37%, although it can vary depending on the population studied, survey methods, and criteria for defining the presence of urinary leakage (whether it occurs weekly, monthly, or at any time in the past). Overall, SUI is the most prevalent type of urinary incontinence, followed by mixed (33%) and urge (20%) incontinence ( Table 1 ). It is important to differentiate the types of leakage as the pathophysiology and treatments are different ( Table 2 ).
| Stress urinary incontinence | The complaint of involuntary leakage of urine on effort or exertion, or on sneezing or coughing |
| Urge urinary incontinence | The involuntary leakage of urine accompanied by, or immediately preceded by, a strong desire to pass urine (void). Urgency, with or without urge urinary incontinence, usually with frequency and nocturia is also defined as Overactive bladder syndrome (OAB). |
| Mixed urinary incontinence | The involuntary leakage of urine associated both with urgency and with exertion, effort, sneezing or coughing. Usually, one of these is predominant, ie. either the symptoms of urge incontinence, or those of stress incontinence, are most bothersome. |
| Overflow incontinence | This occurs when the bladder becomes large and flaccid and has little or no detrusor tone or function. It is usually due to injury or insult, eg. postsurgery or postpartum. The bladder simply leaks when it becomes full. |
| Incontinence due to a fistula | Incontinence resulting from a vesicovaginal, ureterovaginal or urethrovaginal fistula. |
| Congenital incontinence | Congenital causes, e.g. ectopic ureter. |
| Type of leakage | Symptoms | Urodynamic observations |
|---|---|---|
| Stress urinary incontinence | Involuntary leakage during effort, exertion, coughing, or sneezing. | Urodynamic stress incontinence (USI) occurs due to increased abdominal pressure without detrusor contractions. |
| Urge urinary incontinence | Involuntary leakage associated with urgency, often accompanied by symptoms like urgency, frequency, and nocturia. | Detrusor overactivity (DOA) occurs due to involuntary detrusor contractions. |
| Mixed urinary incontinence | Reports of both stress and urge urinary incontinence; both USI and DOA are present. | Urodynamic observations include measuring abdominal and bladder pressure using bladder and rectal catheters attached to pressure transducers. |
Pathophysiology of SUI
SUI is due to urethral incompetence or weakness. A rise in abdominal pressure causes urine to leak past the urethra, which is not able to maintain a tight seal. There are two causes:
- 1.
Urethral hypermobility: This is due to the loss of suburethral support provided by the underlying anterior vaginal wall (pubocervical fascia), which acts as a hammock. The bladder neck and urethra are compressed and occluded against this hammock when there is raised abdominal pressure, preventing SUI ( Figure 1 ). Loss of support can occur because of trauma secondary to childbirth.
Figure 1
The role of suburethral support in preventing stress incontinence. Reproduced from Obloza A et al. Surgical treatment of stress urinary incontinence in women. Obstet. Gyn. Reprod. Med. 2021; 31(7): 205–212 with permission from Elsevier.
- 2.
Intrinsic sphincter deficiency: This is due to damaged urethral sphincter muscles and urethral mucosal cushions. The urethra is open at rest, resulting in significant leakage with even small increases in abdominal pressure. Causes include scarring, ischaemia, and denervation because of childbirth, surgery, or radiotherapy.
Although urethral hypermobility and intrinsic sphincter deficiency are described as two distinct entities, it is likely that SUI is due to a combination of these problems in varying proportions. The risk factors for SUI are multifactorial and can be categorized into factors that predispose, trigger, promote, or cause decompensation of a stable situation ( Figure 2 ). These risk factors include genetic predisposition, pelvic surgery, aging, obesity, smoking, and childbirth.
Surgical considerations
Initial treatment for SUI should be nonsurgical and consists of supervized pelvic floor exercises and lifestyle adjustments where relevant. Surgery may be considered if conservative management fails. The lifetime risk of surgery for SUI is 13.6%.
Several factors influence both the clinician’s and patient’s opinion on whether to undertake surgery and, if so, which procedure is ultimately chosen by the patient with clinician guidance:
- 1.
Presenting complaint: A thorough history is key to successful surgery. The history should clearly describe SUI, as these surgeries are not designed to address overactive bladder symptoms (urgency, urge leakage of urine, frequency, and nocturia). These symptoms can improve but may also worsen after such surgery. Symptoms of voiding difficulty (sensation of incomplete bladder emptying, hesitancy, poor stream, and straining) should be sought, as they are risk factors for postoperative urinary retention and voiding difficulty. It is important to determine which symptoms are bothersome rather than whether they are merely present or not so that treatment addresses the actual problem. Both the severity and impact of symptoms influence the choice of treatment, as women with SUI causing minimal impact may not need or want surgery.
- 2.
Urodynamic studies: Urodynamics studies are not necessary prior to initiating conservative treatment for SUI. They are usually carried out prior to surgery to confirm the presence of urodynamic stress incontinence and to identify other abnormalities such as detrusor overactivity and voiding dysfunction. The presence of detrusor overactivity may result in worsening overactive bladder symptoms after surgery. Pre-existing voiding dysfunction (raised postvoid residual urine volume and decreased urinary flow rate) increases the risk of postoperative urinary retention.
- 3.
Obstetric history: The desire for more children should be established. Generally, surgery should be postponed until the family is complete, as a successful operation may fail after another pregnancy. The mode of delivery may also change, with caesarean section being recommended to protect a successful procedure rather than for purely obstetric indications.
- 4.
Previous surgical history: Previous abdominal and vaginal surgery increases the risk of visceral injury and bleeding because of anatomical distortion due to scarring. The type of surgery offered also depends on previous surgical procedures for SUI. The outcome of surgery is also affected as the effectiveness of surgery for recurrent SUI is lower than for first-time operations.
- 5.
Comorbidities: Medical fitness for surgery and anaesthesia will influence treatment options. A raised BMI is a risk factor for SUI and increases the risk of surgical intervention. It also compromises the efficacy of surgery. Women with raised BMI should be encouraged to lose weight, although their ability to do so by exercising is often hampered by their SUI.
- 6.
Physical examination: The presence of significant prolapse can alter the evaluation and treatment of coexisting SUI. For instance, a prolapse repair in combination with a continence procedure may be the preferred first-line treatment instead of conservative treatment if a large prolapse is present. Combined prolapse and continence procedures increases the complexity of surgery.
- 7.
Patient choice: It is crucial for the patient to be fully informed about all available treatment options, including their cure rates, potential complications, procedural invasiveness, and recovery times. This will enable the patient to make well-informed decisions regarding their treatment. The NICE patient decision aid on surgery should be utilized to support this process.
- 8.
MDT discussion: This is a requirement prior to all continence procedures and is crucial for ensuring appropriate management.
Practice points for surgical considerations in SUI management
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Nonsurgical first: start with pelvic floor exercises and lifestyle changes before considering surgery.
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Detailed history: clarify symptoms to differentiate SUI from overactive bladder.
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Urodynamics: perform prior to surgery to confirm diagnosis and identify any complications.
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Family planning: delay surgery until after childbearing if applicable.
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Surgical history: consider previous surgeries that may impact risk and outcomes.
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Assess comorbidities: evaluate overall health and BMI; encourage weight management.
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Examine for prolapse: identify significant prolapse that may require combined procedures.
- •
Informed choice: provide comprehensive information on treatment options and outcomes.
- •
MDT discussion: involve a multidisciplinary team in pre-surgical planning.
Surgery for SUI
Broadly, the operations for SUI fall into two categories:
- 1.
Procedures to support or stabilize the bladder neck or urethra (recreating suburethral support). These operations include:
- •
Colposuspension
- •
Midurethral tape (MUT)
- •
Autologous fascial sling (AFS)
- •
- 2.
Procedures to augment urethral closure (classically to treat intrinsic sphincter deficiency). These operations include:
- •
Bladder neck injection (BNI) (Urethral Bulking)
- •
Artificial urinary sphincter
- •
The choice of surgical procedure for stress incontinence depends on the underlying pathophysiology. Surgical treatments generally address either bladder neck hypermobility or intrinsic sphincter deficiency, although both conditions can coexist in the same patient.
Urethral hypermobility can be treated with operations that support the bladder neck or hypermobile urethra, such as colposuspension, MUT and sling procedures. However, BNI can also be employed. Intrinsic sphincter deficiency is managed with procedures aimed at improving sphincter function and urethral closure, such as urethral bulking agents, MUT, AFS or artificial sphincter insertion. If the bladder neck is already well supported, colposuspension is unlikely to be beneficial and would be an inappropriate intervention.
When deciding on surgery, a balance must be struck between efficacy and potential complications. For example, a woman may opt for BNI, accepting the procedure’s moderate efficacy, quick return to normal activities and low risk of long-term urinary retention. Surgical procedures should be tailored to the individual woman’s clinical features. Informed consent for a surgical procedure should include a detailed discussion of the risks and benefits of the proposed operation. Additionally, to enable the woman to make an informed choice, she should be aware of the risks and benefits of other procedures.
Anyone considering continence surgery should be informed of the procedure’s failure rate, as well as the risks of de novo detrusor overactivity and urinary retention, both of which may be permanent. Results can vary between surgeons, so where possible, the results of the specific surgical unit should be audited and presented.
The National Institute for Health and Care Excellence (NICE) recommends colposuspensions and autologous slings as first-line surgical treatments for stress urinary incontinence. Until recently, midurethral tapes were the most frequently performed procedure for stress urinary incontinence due to their efficacy and minimally invasive nature. However, in July 2018, NHS England announced a suspension on the use of midurethral tapes for treating stress urinary incontinence due to growing concerns about mesh-related problems, particularly pelvic pain and vaginal mesh erosion. This suspension led to a dramatic decline in the number of continence procedures performed and prompted a reassessment of surgical approaches. As a result, there has been a renewed focus on established methods such as laparoscopic colposuspension and autologous fascial slings. There has been a corresponding significant increase in Urethral bulking/BNI procedures which are now the most popular first line procedure ( Figure 3 ).
