URINARY INCONTINENCE

72 URINARY INCONTINENCE

General Discussion

Urinary incontinence is caused by disturbance in the storage function, and occasionally in the emptying function, of the lower urinary tract. A continent sphincter mechanism requires proper angulation between the urethra and the bladder, as well as proper positioning of the urethra so that increases in intra-abdominal pressure are effectively transmitted to the urethra.

Women may undergo an anatomical or neuromuscular injury during childbirth but remain clinically asymptomatic as long as there is compensation by other components of the continence mechanism. Incontinence may not present in a woman until she loses a small percentage of muscle strength and innervation to the urethral sphincter due to aging or other injuries.

Stress incontinence is the involuntary loss of urine during an increase of intra-abdominal pressure. Stress urinary incontinence arises when bladder pressure exceeds urethral pressure during activities such as coughing, laughing, or exercising. The underlying abnormality is typically urethral hypermobility caused by a failure of the normal anatomic supports of the bladder neck. Intrinsic urethral sphincter deficiency, the lack of normal intrinsic pressure within the urethra, may also lead to stress incontinence.

Overactive bladder, also known as urge incontinence, is the involuntary loss of urine preceded by a strong urge to void whether or not the bladder is full. Urge incontinence results from bladder contractions that overwhelm the ability of the cerebral centers to inhibit them. This bladder oversensitivity may originate from the bladder epithelium or detrusor muscle as the result of altered neural activation in the voiding cycle.

Overflow incontinence is urine loss associated with overdistention of the bladder, typically caused by an underactive detrusor muscle and/or outlet obstruction. Patients may present with frequent or constant dribbling, overactive bladder, or stress incontinence. Causes of detrusor muscle underactivity are outlined below. Overflow incontinence is relatively uncommon but is more common in men because of the prevalence of obstructive prostate gland enlargement.

The first goal of the evaluation of urinary incontinence is to identify reversible causes of incontinence so that effective treatments may be instituted. The second goal is to identify conditions that may require special evaluation or referral to a urologist or urogynecologist. Once transient causes and indications for specialty evaluation or referral have been excluded, the third goal is to decide if the patient’s symptoms are more suggestive of urge incontinence or stress incontinence. After this has been determined, treatment may be initiated accordingly. If the treatment is ineffective, specialty evaluation may be indicated.

Indications for special evaluation or referral detected by history include the following: recent onset within 2 months of urge incontinence or irritative bladder symptoms, previous surgery for incontinence, previous radical pelvic surgery, or incontinence associated with recurrent symptomatic urinary infections. Physical findings that usually require specialty referral include prostate nodules or asymmetry, gross pelvic prolapse, and neurologic abnormalities suggesting a systemic disorder or spinal cord lesion. Hematuria without infection and significant persistent proteinuria on urinalysis require additional evaluation. Other situations that may require special evaluation or referral are an abnormal postvoid residual volume, treatment failure, consideration of surgical intervention, or an inability to arrive at a presumptive diagnosis and treatment plan.

Tags: Instant Work-ups A Clinical Guide to Medicine

Aug 17, 2016 | Posted by admin in PEDIATRICS | Comments Off

Full access? Get Clinical Tree

Get Clinical Tree app for offline access

Get Clinical Tree app for offline access