Bladder and Micturition

Question 1

Be sure to know the __________.

Answer 1

micturition cycle

Question 2

What are the three layers of the bladder?

Answer 2

Outer: peritoneum
Middle: connective tissue and smooth muscle (detrusor muscle)
Inner: mucosal layer

Question 3

Parasympathetic nerves innervate the ___________.

Answer 3

detrusor muscle, resulting in contraction and micturition

Question 4

Sympathetic activation leads to ___________ in the bladder.

Answer 4

contraction of the urethral sphincter

Question 5

Which nerves innervate the bladder and urethra?

Answer 5

S2 - S4 (“S2, 3, and 4 keep the penis off the floor”)

Question 6

There are voluntary and involuntary mechanisms of continence. What are the two main muscles?

Answer 6

Striated: external rhabdosphincter (men and women)
Smooth muscle: mid-urethra complex (women)
Smooth muscle: sphincter complex of the prostate and membranous urethra (men)

Question 7

What is micturition?

Answer 7

Voiding of the bladder

Question 8

List the five stages of micturition, in order.

Answer 8

1) Increase in wall tension in the bladder
2) Afferent input overcomes the pontine micturition center threshold and provides cortical egress; micturition begins
3) Pudendal nerve activity ceases, the external sphincter/pelvic floor relaxes, detrusor neurons are freed and discharge
4) Proximal urethra opens
5) Bladder immediately contracts

Question 9

Disorders in the micturition cycle lead to ___________.

Answer 9

hesitancy, weak stream, incomplete emptying, or retention

Question 10

What factors in the patient’s history predispose them to incontinence?

Answer 10

Diabetes (neuropathy)
Bowel problems
Neurological disorders 
Pelvic surgery
Spinal surgery
Bladder outlet procedures

Question 11

What is the main medical treatment for overactive bladder?

Answer 11

Antimuscarinic therapy (such as the anticholinergic drug oxybutynin)

Question 12

What is the main medical treatment for overactive bladder?

Answer 12

Antimuscarinic therapy

Question 13

Sympathetic innervation of the bladder passes along the _______ nerve.

Answer 13

hypogastric (from T10 - L2 chain ganglia)

Question 14

The voluntary muscles of the bladder pass along the _________ nerve.

Answer 14

pudendal (S2 - S4)

Question 15

Disorders of the storage phase of micturition lead to ______________.

Answer 15

increased frequency, urgency, and urge incontinence

Question 16

Urge incontinence results from ____________; stress incontinence results from ___________.

Answer 16

overactive detrusor muscle; underactive outflow muscles

Question 17

Overflow incontinence can result from _____________.

Answer 17

underactive detrusor muscle or overactive outflow muscle

Question 18

What are some red flags that incontinence might be associated with another pathology?

Answer 18

Persistent hematuria
Failure to respond to treatment
Recent surgery
Masses

Question 19

Refractory overactive bladder can be treated with __________.

Answer 19

botox