Neurological Control of Urinary Function

Question 1

What vertebrae are involved in the neurological control of the bladder?

Answer 1

L1 - L4 (Hypogastric nerve)

S1 - S3 (Pelvic and Pudendal nerve)

Question 2

What are the roles of the urethra?

Answer 2

Outflow tract

Containment

Question 3

What is the m of the bladder? What kind of muscle is it?

Answer 3

Detrusor muscle

Smooth muscle

Question 4

What are the muscles and types of muscles of the urethra?

Answer 4

Internal urethra sphincter - Smooth

External urethra sphincter - Skeletal

Question 5

What types of nervous innervation occurs during the storage phase in bladder control?

Answer 5

Sympathetic

Somatic

Question 6

Outline the sympathetic innervation during the storage phase of bladder control….

Answer 6

Hypogastric nerve –> a and B adrenergic receptors –> detrusor muscle relaxes and urethral sphincter contracts

Question 7

Outline the somatic innervation during the storage phase

Answer 7

Pudendal nerve –> nicotinic ACh receptors –> urethral sphincter contracts

Question 8

What type of innervation is responsible for the voiding phase in bladder control?

Answer 8

Parasympathetic

Question 9

Outline the parasympathetic innervation of the voiding phase in bladder control…

Answer 9

Pelvic muscle –> muscarinic ACh receptors –> bladder contracts

Question 10

Where can the lesion occur in UMN bladder?

Answer 10

Pons –> L7 SC

Question 11

What are the sings of UMN bladder?

Answer 11

Turgid, easily palpable bladder
Increased urinary sphincter tone
Difficult to express

Question 12

Where can the lesion occur in LMN bladder?

Answer 12

Sacral SC or nerves

Question 13

What are the signs of LMN bladder?

Answer 13

Flaccid, difficult to palpate bladder
Decreased urinary sphincter tone
Difficult to express

Question 14

What are the problems associated with neurogenic bladder dysfunction?

Answer 14

Incontinence
Urine scolding
Urine stasis
UTI
Detrusor atony
Pain/discomfort

Question 15

Why can both UMN and LMN bladder result in incontinence?

Answer 15

UMN -> High intrabladder pressure so leaks

LMN -> Pressure from outside sources

Question 16

How can the neurogenic bladder be managed physically?

Answer 16

Manual expression
Catheterisation
Cystostomy tube placement

Question 17

What drugs can be used to help manage the neurogenic bladder?

Answer 17

- Retention
Diazepam
Bethanchol
Phenoxybenzamine
Prazosin

• Incontinence
  Phenylpropanolamine

Question 18

Outline the mechanism of diazepam in treating neurogenic bladder dysfunction…

Answer 18

Centrally acting muscle relaxant that decreases external urethral sphincter

Question 19

Outline the mechanism of bethanechol in treating neurohenic bladder dysfunction…

Answer 19

Muscarinic cholinergic agonist that facilitates detrusor muscle contractility

Question 20

Outline the mechanism of phenoxybenzamine and prazosin in treating neurogenic bladder dysfunction…

Answer 20

Alpha adrenergic antagonist that decreases internal urethral sphincter tone

Question 21

Outline the mechanism of phenylpropanolamine in treating neurogenic bladder dysfunction…

Answer 21

Mixed alpha and beta agonist that increases internal urethral sphincter tone