This document discusses the management of overactive bladder. It begins by describing the normal bladder functions of storage and emptying. It then discusses overactive bladder, noting it is defined by symptoms of urgency and frequency. Causes can be neurologic or myogenic defects. Evaluation involves history, exam, urodynamics and cystoscopy. Treatment begins with lifestyle changes and pharmacotherapy using antimuscarinic drugs to inhibit bladder contractions. For refractory cases, options include intravesical injections, botulinum toxin, neuromodulation or urinary reconstruction. Overall understanding of overactive bladder pathophysiology and treatment options has improved.

1. Practical Approaches to
The Management of
Overactive Bladder
DR. Talal Ballout
Urologest

2. Bladder Properties
• Bladder is one of the most compliant organs of the body
• Should provide perfect continence
• Voluntary and efficient emptying at low pressure

3. Micturition Cycle
• Fill and store
• Empty completely
- simple but important phases
- important to help classify and treat disorders
of micturition

4. Bladder Filling and Storage
• Accommodates large volumes of urine
- maintains low intravesical pressure
(< 12 cm water)
- sustains sensation that is appropriate
• No involuntary contractions
- hyperreflexia, overactivity, reflex contractions or
instability
• Maintain a closed and continent outlet at rest
even with sudden intra-abdominal forces

5. Bladder Emptying
• Bladder contraction
- adequate magnitude
- sustained to empty
• Coordinated urethral relaxation
- bladder neck and proximal urethral smooth muscle
- striated external urethral sphincter
• No anatomic obstruction

6. Parasympathetic Muscarinic Receptors
• M1- neuronal, brain
• M2- cardiac, detrusor
• M3- detrusor, gastrointestinal smooth muscle, salivary
glands
• M4 + M5
• M3 receptors (20%) responsible for smooth muscle
contraction
• M2 receptors (80%) responsible for inhibition of smooth
muscle relaxation

7. Overactive Bladder
• Clinical term used to describe symptoms of frequency,
urgency, +/- urge incontinence
- term used without knowing specific cause of symptoms
(eg, detrusor overactivity)
• ICS 2002–Urgency with or without urge incontinence,
usually with frequency and nocturia
- absence of pathologic or metabolic conditions that might
explain these symptoms

8. Overactive Bladder Pathophysiology
• Multifactorial disorder
• A constellation of functional abnormalities
• 90% of cases idiopathic
• Can be caused by:
- neurologic defects
- myogenic defects

9. Overactive Bladder Neurologic Defects
• CVA
• Dementia (eg, vascular disease, Alzheimer’s,
encephalitis)
• Cerebral palsy
• Brain tumor
• Parkinson’s disease
• Multiple sclerosis
• Shy-Drager syndrome

10. Overactive Bladder and Spinal Cord
Injury
• Complete suprasacral lesions above T7
- detrusor hyperreflexia
- smooth sphincter dyssynergia
- striated sphincter dyssynergia
- no sensation
• Complete suprasacral lesions below T7
- detrusor hyperreflexia
- smooth sphincter synergy
- striated sphincter dyssynergia
- no sensation

11. Overactive Bladder Patient Evaluation
• History
• Physical
• Urodynamics
• Cystoscopy

12. History
• Urologic
• Ob/Gyn
• Neurologic
• Medical/surgical
• Social/psych
• Radiation
• Pelvic trauma

13. Incontinence History
• Characterization of incontinence
• Length and severity of symptoms
• Impact on quality of life
• Associated bowel problems

14. Physical Exam Women
• Systematic vaginal and pelvic exam
- condition of mucosa
- urethral mobility (Q tip test)
- demonstration of continence (CST)
- vaginal prolapse (anterior wall, posterior wall, apical)
- bimanual exam

15. Physical Exam
• Men–DRE and urogenital exam
• Neurologic exam
- mental status
- mobility
- lumbar and sacral sensory and motor
eg, BC reflex, anal wink, knee and ankle DTR’s

16. Ancillary Tests
• Voiding and intake diary
- Extremely important especially in cases of overactive
bladder
• Incontinence diary
• Urine analysis
- urine culture and cytology when indicated
• Post void residual
• Pad test

17. Role of Cystometry
• Defining underlying pathophysiology
- bladder filling
- involuntary detrusor contractions
- low bladder compliance
- urethral obstruction
- impaired detrusor contractility
• Directing treatment

18. Pharmacologic Treatment of Bladder
Overactivity
• Decrease detrusor activity
- abolish involuntary detrusor contractions
- increase volume at which they occur
- increase compliance
• Increase bladder capacity
• Commonly used agents focus on inhibition at the end
organ level

19. Pharmacologic Agents
Bladder Overactivity
• Antimuscarinics
• Muscle relaxants
• Mixed action drugs
• Tricyclic antidepressants
• Alpha blockers
• Beta agonists
• Vasopressin analogues

20. Antimuscarinics
• Antimuscarinics (anticholinergic) drugs have been the
mainstay of medical therapy for bladder overactivity
• Have been somewhat limited by the high incidence of
side effects and lack of selectivity

21. Mechanism of Action of Antimuscarinics
• Inhibit bladder contraction
- ACh from cholinergic nerves stimulate muscarinic
receptors
- block stimulation of muscarinic receptors

22. Antimuscarinic Agents of Common
Side Effects
• Dry mouth
• Constipation
• Drowsiness/somnolence
• Blurred vision/dry eyes

23. Antimuscarinics 2007
• Oxybutynin IR BID-TID
• Oxybutynin ER QD
• Oxybutynin TDS BIW
• Tolterodine IR/ER BID/QD
• Tropsium BID
• Solifenacin QD
• Darifenacin QD

24. What is the Difference?
• Efficacy
- no great differences
- dose-dependent
• Tolerability
• Safety
• Clinical effectiveness–different for different patients
depending on expectations

25. Imipramine
• Prominent systemic anticholinergic effects
• Weak antimuscarinic effects on the bladder
• Strong direct inhibitory effect on bladder smooth muscle
which is not anticholinergic or adrenergic
• Decreases contractility/increases outlet resistance
• Effects on lower urinary tract are additive to those of
atropine-like agents; useful in combo with other
anticholinergics
• Most common side effects
- anticholinergic effects, weakness, fatigue, sedation

26. Combination Pharmacotherapy
• Combination therapy–combining 2 drugs that have
different actions, eg, anticholinergic and tricyclic
• Intravesical instillation of Oxybutynin
- works best in cases where oral form is effective but
patients can’t tolerate side effects
- requires self-catheterization

27. Evaluation of Refractory
Overactive Bladder
• Post void residual
• Comprehensive urodynamic testing
• Cystoscopy
• Urine cytology
• Upper tract study
- renal ultrasound
- CT/MRI
- IVP
• Neurological evaluation, if necessary

28. Refractory Detrusor Overactivity
• Intravesical instillations–Capsaicin
• Botulinum-A Toxin
• Neuromodulation
- efficacy in neurogenic overactivity not universally
accepted
• Urinary reconstruction
- augmentation
- diversion

29. Conclusion
• Improved understanding of
pathophysiology
• Contribution of alternate neural receptors
• Better understanding of receptor action
and interaction
• Mechanism of action of antimuscarinics
and side effects