Week 4: Normal Micturation and voiding dysfunction

Question 1

Frequency and impact of incontinence in the US

Answer 1

• 10-35% of adults are affected by incontinence

- 2x as many women as men, mostly nursing home residents

Question 2

Neuroanatomy and function of normal voiding.

Answer 2

• continence is learned: cognitive control over a reflex bladder contraction
  1. Sensory afferent nerves sends signals from bladder to T10-L2 then to brain that bladder is full via Pudendal nerve. Activates spinobulbospinal reflex pathway passing through pons
• pontine micturition center activated, cortical inhibitory tone released
  2. parasymp stimulation of detrusor muscle activated via S2-S4 via pelvic nerves
  3. signaling to bladder neck and urethra inhibits contraction via inhibition of symp and somatic nerves (sphincter tone) and allows voiding

Question 3

Causes of abnormal bladder function in filling, storage, emptying

Answer 3

FILLING
-poor compliance
-overactive bladder
-poor sphincter activity
-disruption in connection and communication between brain and bladder
-injury to cortex/brain
STORAGE
-overstretched detrusor: chronic obstruction or loss of sensation
-injury to spinal cord
-injury to pons
EMPTYING
-non-relaxation of outlet
-obstructed outlet
-poor bladder contraction (areflexia)-easily stretched, can overfill and leak

Question 4

Etiology of abnormal bladder function

Answer 4

1. Idiopathic (non-neurogenic)
   - must rule out BPH, UTI, bladder tumor, stones, polyuria secondary to …
2. Neurogenic: can be upper motor or lower motor neuron problem
   - MS, spinal cord injury, transverse myelitis, CVA, parkinsons

Question 5

Differentiate between lower and upper motor neuron

Answer 5

UPPER MOTOR NEURON
1. bladder: detrusor overactivity with
2. sphincter: 
-supersacral spinal cord lesion-->sphincter dyssynergia. Usually have coordination of bladder contraction with sphincter relaxation, but can have sphincter contraction while bladder contraction with interruption in voiding
-at or above brains ten-->synergistic sphincter: doesn't affect pontine center of micurition which coordinates detrusor and sphincter activity
LOWER MOTOR NEURON
1. Bladder: areflexic
2. Sphincter: normal to decreased

Question 6

Categorization of void dysfunction

Answer 6

1. Stress incontinence: underactive urethra
2. urgency incontinence: overactive bladder-mixed stress and urge
3. overflow: underactive bladder or overactive urethra or both
4. functional
5. iatrogenic
6. transient

Question 7

Stress urinary incontinence

Answer 7

• due to poor outlet resistance: sphincter problem
• symptoms: cough, sneeze, exercise incontinence
• small amounts of urine loss
• no feelings of urgency or frequency

Question 8

urge incontinence

Answer 8

• due to bladder overactivity
• may coexist with stress urinary incontinence
• origin: idiopathic or neurologic
• symptoms: urgency prior to leakage or leakage without awareness
• wet at night or nocturne, frequency, urgency, often large volume, no relationship to activity

Question 9

overflow

Answer 9

• due to failure to empty
• outlet obstruction or poor contractility or both: neurologic, BPH, diabetes, radical pelvic surgery
• symptoms: straining to void, poor sensation, frequency

Question 10

Functional incontinence

Answer 10

• normal lower urinary tract but unable to toilet due to physical or cognitive limitations
• s/p joint replacement, back surgery, dementia

Question 11

Iatrogenic Incontinence

Answer 11

• Treatment related/physician neglect
• diuretics, bladder over distention after spinal anesthetic
• medications: antihistamines, anticholinergics, antidepressants

Question 12

treatment for overactive bladder

Answer 12

• pads, behavior therapy, medications, neuromodulation, surgery
• anticholinergics