What is the management of urination (micturition)?

From the Guidelines

Micturition management should prioritize nonpharmacologic therapies, such as pelvic floor muscle training, bladder training, and weight loss with exercise for obese women, due to their effectiveness and low risk of adverse effects. When considering management strategies, the following approaches can be effective:

• Pelvic floor muscle training alone or in combination with bladder training or biofeedback to achieve continence and improve urinary incontinence (UI) 1
• Weight loss with exercise for obese women to manage UI
• Nonpharmacologic therapies have a large magnitude of benefit for increasing continence rates and are associated with a low risk for adverse effects 1 For patients who may require pharmacologic therapies, options such as solifenacin, darifenacin, and tolterodine can be considered, as they have been shown to be effective in managing urgency UI with a moderate magnitude of benefit in achieving continence rates 1. However, it is essential to note that pharmacologic therapies are associated with adverse effects, and some patients may discontinue treatment due to these effects 1. In terms of specific medications, solifenacin is associated with the lowest risk for discontinuation due to adverse effects, whereas oxybutynin is associated with the highest risk 1. Ultimately, the choice of management strategy should be individualized based on the patient's specific needs and circumstances.

From the FDA Drug Label

CLINICAL STUDIES Tolterodine tartrate tablets were evaluated for the treatment of overactive bladder with symptoms of urge urinary incontinence, urgency, and frequency in four randomized, double-blind, placebo-controlled, 12-week studies. The efficacy endpoints for study 007 (see Table 3) included the change from baseline for: • Number of incontinence episodes per week • Number of micturitions per 24 hours (averaged over 7 days) • Volume of urine voided per micturition (averaged over 2 days) Oxybutynin chloride relaxes bladder smooth muscle In patients with conditions characterized by involuntary bladder contractions, cystometric studies have demonstrated that oxybutynin chloride increases bladder (vesical) capacity, diminishes the frequency of uninhibited contractions of the detrusor muscle, and delays the initial desire to void Oxybutynin chloride thus decreases urgency and the frequency of both incontinent episodes and voluntary urination.

Micturition Management:

• Tolterodine and oxybutynin are used to manage symptoms of overactive bladder, including urge urinary incontinence, urgency, and frequency.
• These medications help to decrease the frequency of micturitions and incontinent episodes.
• Tolterodine has been shown to increase the volume of urine voided per micturition.
• Oxybutynin increases bladder capacity and delays the initial desire to void, thus decreasing urgency. 2 and 3

From the Research

Micturition Management

Micturition management involves the treatment of disorders related to the storage and emptying functions of the bladder.

• The main symptoms of disturbances of storage function are frequency, urgency, and incontinence 4.
• Hyperactivity of the bladder may lead to urge incontinence, and incompetence of the urethral closure mechanism to stress incontinence 4.
• The central control of micturition in women involves a complex network of neurons that allow storage of urine followed by voiding when socially appropriate 5.

Treatment Options

Treatment options for micturition disorders include:

• Anticholinergic drugs to depress bladder hyperactivity 4.
• Drugs with "mixed" actions, such as oxybutynin and terodiline, to treat bladder hyperactivity 4.
• Orally active alpha-adrenoceptor agonists, such as phenylpropanolamine, and/or oestrogens to increase outflow resistance and treat stress incontinence 4.
• Parasympathomimetic agents, such as bethanechol or carbachol, and intravesical instillation of prostaglandins to improve bladder contractility 4.
• Alpha-adrenoceptor blockers, such as phenoxybenzamine or prazosin, to reduce urethral outflow resistance 4.

Neurophysiology of Micturition

The neurophysiology of micturition and continence in women involves the coordination of complex neural events between the central and peripheral nervous systems 6.

• Understanding the neuroanatomy, neurophysiology, and neuropharmacology of micturition and continence provides a foundation for the treatment of voiding disorders in women 6.
• Clinical correlations can help integrate basic science with clinical observations 6.

Urodynamic Analysis

Urodynamic analysis can help define symptoms and symptom complexes associated with the presence or absence of detrusor instability 7.

• Patients with recurrent urinary tract infection or stress incontinence in the absence of other micturition symptoms usually have stable bladders 7.
• The symptom of urge incontinence associated with persistent frequency and nocturia has a high correlation with detrusor instability 7.

Emergency Management

Acute urinary retention is a common presentation to emergency departments and requires appropriate management, investigations, and guidelines 8.

• Urethral catheterization techniques, suprapubic catheterization procedures, and management of acute urinary retention in polytrauma are important considerations in emergency management 8.