[04.10] SUR - Voiding Dysfunction V2.1.pdf

Urinary bladder, urethral sphincters, and urethra (plus prostate gland in males)

What anatomical structures comprise the male lower urinary tract?

Urinary bladder, urethral sphincters, and urethra

What anatomical structures comprise the female lower urinary tract?

Prostate gland

Which accessory organ of the lower urinary tract is uniquely present in males?

Female urethra is significantly shorter than male urethra

How does the length of the female urethra compare to that of the male urethra?

Stores urine and contracts to expel urine

What are the two primary functions of the urinary bladder?

Internal urethral sphincter

Which urethral sphincter is under involuntary autonomic control?

External urethral sphincter

Which urethral sphincter is under voluntary somatic control?

Conducts urine from the urinary bladder to the outside of the body

What is the anatomical function of the urethra?

Penile, bulbar, membranous, and prostatic segments

What are the four anatomical segments of the male urethra?

Two ureteral orifices

What paired anatomical openings are visible inside the urinary bladder?

Detrusor muscle

Which smooth muscle layer of the bladder contracts to cause voiding?

Trigone

What triangular mucosal region inside the urinary bladder is marked by the ureteral orifices and bladder neck?

Bladder neck

What anatomical region marks the termination of the urethra and the beginning of the urinary bladder?

Filling phase

Which phase of lower urinary tract function is controlled by the sympathetic nervous system?

Inhibits detrusor muscle contraction (causes bladder relaxation) and contracts the bladder neck

What are the two motor effects of sympathetic stimulation on the lower urinary tract?

T11 to T12 nerves

What are the spinal cord origins of the sympathetic nerve supply to the lower urinary tract?

Aortic plexus, superior hypogastric plexus, and inferior hypogastric plexus

Which three nerve plexuses carry sympathetic fibers to the lower urinary tract?

Voiding phase

Which phase of lower urinary tract function is controlled by the parasympathetic nervous system?

Stimulates detrusor muscle contraction and facilitates voluntary relaxation of the urinary sphincter

What are the motor effects of parasympathetic stimulation during micturition?

S2 to S4 nerves

What are the sacral spinal cord origins of the parasympathetic nerve supply to the lower urinary tract?

Pelvic splanchnic nerves and pudendal nerves

Which nerve pathways transmit parasympathetic and somatic impulses to the lower urinary tract?

Cerebral cortex, pontine micturition center, and spinal cord

What three central nervous system structures regulate micturition?

Interprets sensory information regarding bladder fullness, regulates micturition, and initiates the conscious desire to void

What three roles does the cerebral cortex perform in micturition control?

Switches between sympathetic and parasympathetic activation, signals filling vs voiding phase, and relays ascending sensory data

What are the three main functions of the pontine micturition center?

Autonomic nervous system (sympathetic and parasympathetic branches)

Which division of the nervous system provides involuntary motor control over the bladder?

Somatic nervous system

Which division of the nervous system provides voluntary control over urination via the external sphincter?

Accommodation

What term describes the process wherein intravesical pressure remains low despite an increasing volume of stored urine?

Sympathetic nervous system relaxation of the detrusor muscle

What neural mechanism enables bladder accommodation during the filling phase?

Closed bladder outlet and absence of involuntary detrusor contractions

What two conditions must be maintained during a normal filling phase?

Onset of the urge to void

What clinical sensory threshold marks entry into the emptying phase of micturition?

Parasympathetic nervous system

Which autonomic nervous system division controls the emptying phase of micturition?

Contraction of the detrusor muscle with concomitant lowering of sphincter resistance

What two physical actions occur during the emptying phase?

Somatic nervous system

Which nervous system division primarily controls the final voluntary urination phase?

Voluntary relaxation of the external urethral sphincter

What physical action initiates actual urination during the final voiding stage?

Incoordination between bladder muscle contraction/relaxation and urethral sphincter opening/closing

What is the functional definition of voiding dysfunction?

Problem with storage / filling phase function

How is a filling problem classified functionally in voiding dysfunction?

Overactive bladder and urinary incontinence

What are two examples of filling phase voiding dysfunctions?

Problem with the outlet / emptying phase function

How is an emptying problem classified functionally in voiding dysfunction?

Benign prostatic hyperplasia and urethral stricture

What are two examples of male emptying phase voiding dysfunctions?

Female urethral stenosis

What is an example of a female emptying phase voiding dysfunction?

Voiding dysfunction caused by a nervous system disorder affecting the brain, spinal cord, or peripheral nerves

What defines neurogenic voiding dysfunction?

Voiding dysfunction caused by structural or muscular abnormalities rather than a nervous system disorder

What defines non-neurogenic voiding dysfunction?

Motor region of the cerebral cortex or the brainstem

Where do upper motor neurons originate anatomically?

Transmits nerve impulses from the brain to lower motor neurons

What is the neural transmission role of an upper motor neuron?

Near the central nervous system, including the spinal cord

Where are upper motor neurons located relative to the nervous system?

Uncontrolled contraction of the smooth muscles of the urinary bladder

What is the definition of detrusor hyperreflexia?

Stroke, brain tumor, or traumatic brain injury

What three cerebral cortex lesions produce detrusor hyperreflexia?

Urge incontinence

What voiding dysfunction is caused by basal ganglia disease such as Parkinson's disease?

Reflex micturition with detrusor-sphincter dyssynergia

What voiding dysfunction results from spinal cord damage located above T6?

Reflex micturition with detrusor-sphincter synergia

What voiding dysfunction results from spinal cord damage located below T6?

Transmits nerve impulses from upper motor neurons to effector muscles

Where do lower motor neurons transmit impulses?

Located near effector muscles

Where are lower motor neurons located anatomically?

Acontractile bladder and decreased bladder sensation

What two voiding abnormalities result from sacral spinal cord damage or peripheral nerve injury?

Pelvic fracture and cauda equina syndrome

What are two causes of sacral spinal cord lower motor neuron damage?

Diabetes mellitus and pelvic surgery

What are two causes of peripheral nerve damage leading to lower motor neuron voiding dysfunction?

Prostate enlargement, urethral stricture, and surgical or traumatic sphincter injury

What are three common causes of non-neurogenic voiding dysfunction?

Comprehensive history taking

By what clinical method is the majority of voiding dysfunctions diagnosed?

Onset, severity, neurological comorbidities, previous surgical history, and current medications

What five history elements should be elicited in a patient with suspected voiding dysfunction?

Palpation of the urinary bladder, digital rectal examination for sphincter tone, and a focused neurologic examination

What three components must be included in the physical examination for voiding dysfunction?

To rule out an ongoing urinary tract infection

Why is a urinalysis routinely ordered in the evaluation of voiding dysfunction?

To evaluate baseline kidney function, as chronic voiding dysfunction can impair renal function

Why is serum creatinine measured in voiding dysfunction?

KUB (plus prostate) ultrasound

What is the standard initial imaging study requested for voiding dysfunction?

Post-void residual volume of urine

What is the most important parameter physicians evaluate on a renal/bladder ultrasound in voiding dysfunction?

To identify underlying pathologies not detectable by ultrasound

When is a CT scan indicated in the diagnostic workup of voiding dysfunction?

Urodynamic study (Voiding cystometry / Pressure-flow study)

What is the definitive gold standard test used to document voiding dysfunction?

Simultaneous measurement of pressures in the abdomen, bladder, and urethra across all voiding phases

What diagnostic measurements are performed during a urodynamic study?

Intravesical pressure (pressure inside the bladder, Pves)

What does the first (blue) line represent on a urodynamic study tracing?

Abdominal pressure (Pabd)

What does the second (black) line represent on a urodynamic study tracing?

Detrusor pressure (Pdet)

What does the third (green) line represent on a urodynamic study tracing?

Detrusor pressure equals intravesical pressure minus abdominal pressure (Pdet = Pves - Pabd)

How is detrusor pressure calculated mathematically from urodynamic tracing values?

Direct endoscopic visualization of the urethra and urinary bladder lumen

What is cystoscopy?

When a non-neurogenic structural cause (stricture, enlarged prostate, bladder stone) is suspected

When is cystoscopy specifically indicated in voiding dysfunction?

Treat the underlying cause of the voiding dysfunction

What is the primary goal of voiding dysfunction treatment?

Preserve renal function, cure/prevent UTIs, and ensure acceptable social function (continence)

What are three secondary goals of voiding dysfunction management?

Inhibit bladder contractility and decrease the sensation or urge to void

What is the therapeutic goal for bladder storage problems characterized by detrusor overactivity?

Anticholinergics, beta-adrenergic agonists, and calcium channel blockers

What three drug classes inhibit bladder contractility and reduce urinary urge?

Bladder augmentation

Which surgical procedure constructs a new bladder dome using a harvested section of bowel?

Sacral nerve modulation

Which surgical technique involves implanting electrodes to directly stimulate sacral nerves?

Timed voiding

Which behavioral therapy instructs patients to void at fixed schedule intervals regardless of urge?

Double voiding

Which behavioral therapy asks patients to attempt a second voiding effort before leaving the bathroom?

Alpha agonists, beta-adrenergic antagonists, and topical or oral estrogen

What three pharmacologic agents are used to increase bladder outlet resistance?

Bladder neck suspension, urethral slings, periurethral bulking agent injections, and artificial urinary sphincters

What four surgical procedures increase bladder outlet resistance?

Kegel's exercises, biofeedback, and electrical stimulation of the sphincters

What three behavioral therapies strengthen the urethral sphincters?

Increase bladder contractility, decrease outlet resistance, or both

What are the therapeutic goals when treating an emptying phase voiding dysfunction?

Parasympathomimetic agents

Which single pharmacologic class is available to directly increase bladder contractility?

Direct electrical bladder stimulation

What surgical intervention is available to increase bladder contractility?

Valsalva maneuver during voiding

What behavioral maneuver can be performed to assist bladder emptying?

Alpha blockers, 5-alpha reductase inhibitors, phosphodiesterase-5 inhibitors, and botulinum toxin

What four pharmacologic options decrease bladder outlet resistance?

Direct injection into the urethral sphincters

Where is botulinum toxin injected to decrease outlet resistance?

Indwelling Foley catheter, clean intermittent catheterization, and suprapubic catheterization

What three urinary diversion methods bypass bladder outlet resistance?

Catheter is inserted every 6 to 8 hours to drain urine and immediately removed

How is clean intermittent catheterization performed?

Surgically inserted through the anterior abdominal wall above the pubic symphysis directly into the bladder

Where is a suprapubic catheter placed?

Transurethral prostate surgery (prostate resection) and transurethral urethrotomy

What are the two most common surgical procedures used to decrease outlet resistance?

Internal urethrotomy performed for urethral strictures

What is another name for transurethral urethrotomy, and when is it performed?

Accidental or involuntary loss of urine

What is the definition of urinary incontinence?

Involuntary urine loss occurring with increased intra-abdominal pressure (coughing, laughing, lifting, standing)

What defines stress urinary incontinence?

Involuntary urine loss occurring immediately following a sudden, strong desire/urge to void

What defines urge urinary incontinence?

Involuntary urine loss secondary to bladder overdistention or reaching maximum bladder capacity

What defines overflow urinary incontinence?

Any combination of stress, urge, overflow, or functional incontinence

What defines mixed urinary incontinence?

Involuntary urine loss caused by cognitive or physical impairments preventing timely toilet access

What defines functional urinary incontinence?