Neurogenic bladder dysfunction

Question 1

What are the muscles associated with the bladder?

Answer 1

• Smooth muscles: detrusor muscle and urethral muscle

- Skeletal muscle: external sphincter

Question 2

Describe the autonomic function of the bladder

Answer 2

• Parasympathetic = peeing
• Sympathetic = storage
• When your fleeing you shouldn’t be peeing!!

Question 3

What receptors are found in the detrusor muscle?

Answer 3

• Muscarinic cholinergic (parasympathetic)

- Beta adrenergic (sympathetic)

Question 4

What receptors are found in the urethral muscle?

Answer 4

-Alpha adrenergic (sympathetic)

Question 5

What receptors are found in the external sphincter?

Answer 5

-Nicotinic cholinergic (parasympathetic)

Question 6

What nerve is important in voiding?

Answer 6

Pelvic nerve (parasympathetic, cholinergic)

Question 7

Where are the pre-ganglionic cell bodies of neurons that control bladder filling and closure of the urinary sphincter in dogs? In cats?

Answer 7

Dogs: L1-L4
Cats: L2-L5

Question 8

Where are the alpha receptors (sympathetic) located? What are they stimulated to do during the storage and emptying phase?

Answer 8

Bladder neck; they are stimulated during the storage phase to contract and keep bladder neck closed, and blocked during the emptying phase to relax and open the bladder neck and urethra

Question 9

Where are the beta receptors (sympathetic) located? What are they stimulated to do during the storage and emptying phase?

Answer 9

They are located in the bladder body, and stimulated during the storage phase to relax muscle and blocked during the emptying phase to contract the bladder

Question 10

Where are the parasympathetic cholinergic receptors located?

Answer 10

They are located throughout the bladder. They are blocked during the storage phase to relax muscles (for filling) and stimulated during the emptying phase to strengthen the contraction of the bladder muscle

Question 11

What drugs are used to block sympathetic alpha receptors to facilitate bladder emptying?

Answer 11

Phenoxybenzamine and Prazosin (more popular)

Question 12

What drugs are used to block striated urethral muscle to facilitate bladder emptying?

Answer 12

Diazepam (more popular) and dantrolene

Question 13

What drugs are used for cholinergic stimulation of the detrusor muscle to facilitate bladder emptying?

Answer 13

Bethanechol (NO LONGER AVAILABLE)

Question 14

What drug is used as alpha agonist to increase internal sphincter tone to facilitate urine storage?

Answer 14

Phenylpropanolamine

Question 15

What drug is used as an anticholinergic to decrease bladder tone to facilitate urine storage?

Answer 15

Propantheline

Question 16

What estrogen drug is used to increase sphincter tone to facilitate urine storage?

Answer 16

Diethylstilbestrol (only used in dogs)

Question 17

What testosterone drug is used to increase sphincter tone to facilitate urine storage?

Answer 17

Testosterone cypionate (only used in dogs)

Question 18

What are the aims for bladder management?

Answer 18

• Patient welfare (paramount)
• Aid voiding or manual expression
• Prevent urine scalding
• Prevent cystitis
• Prevent muscle tight junctions over-stretching and causing permanent damage

Question 19

What is the problem with an UMN bladder? How is it solved?

Answer 19

• Problem: increased sphincter tone, makes bladder difficult to express
• Solution: diazepam +/- prazosin

Question 20

What procedure is contraindicated with UMN bladder?

Answer 20

Cystocentesis if bladder is very full; repeated catheterization should be avoided