Erectile Dysfunction

Question 1

What is ED?

Answer 1

The inability to attain and/or maintain penile erection sufficient for satisfactory sexual performance

Question 2

What are the 2 normal process involved in erection?

Answer 2

(1) Relaxation of smooth muscles of cavernosal artery increased inflow of blood to corpora cavernosa
(2) Increased venous outflow resistance –> decreased outflow

Question 3

How is there relaxation of smooth muscles of cavernosal arterial wall?

Answer 3

parasympathetic n. release NO

increased CGMP and cAMP

decreased IC Ca > smooth muscle relaxation > vasodilation

Question 4

How is there increased venous outflow resistance?

Answer 4

high inflow to corpora cavernosa causes CC to expand and compress venous sinuses

Question 5

Causes for ED?

Answer 5

Vasculogenic
Neurogenic
Psychogenic
Endocrine
Medication-induced
Disease states

Question 6

Vasogenic causes for ED?

Answer 6

arterial inflow prob

venous outflow prob

Question 7

neurogenic cause for ED?

Answer 7

prostatectomy

Question 8

psychogenic causes for ED?

Answer 8

Depression
Stress
Anxiety
Psychiatric disorders

Question 9

Endocrine causes for ED?

Answer 9

Hyperprolactinemia
Thyroid disorder
Hypogonadism
(SHBG)

usually managed by endocrine

Question 10

What meds can contribute to ED?

Answer 10

antihypertensives

antidepressants/antipsychotics

meds that reduce testosterone

Question 11

Presentation for ED?

Answer 11

ED, impotence, “something”

Question 12

What is Peyronie’s disease?

Answer 12

curvature of the penis

Question 13

What should you check for on PE for pt with ED?

Answer 13

circulation

gynecomastia, galactorrhea, visual field defects

genital exam: penis (plaques-can cause peyronie’s), testes (small can indicate testosterone problems)

Question 14

What time of the day should you check testosterone?

Answer 14

7am-11am

Question 15

What is nocturnal penile tumescence?

Answer 15

“postage stamp”

put what looks like BP cuff around penis, measures erections throughout the night

Question 16

What other dx studies can you use to eval for ED?

Answer 16

penile Doppler US

carvernosometry/cavernosography

Question 17

What does penile Doppler US check for?

Answer 17

arterial insuffiencency

Question 18

What does

Cavernosometry/Cavernosography check for?

Answer 18

venous leak

Question 19

General tx for ED?

Answer 19

Determine if CV status appropriate for sexual activity

Smoking cessation

Weight control

Alcohol

Possible change of medication

Treatment of medical conditions

Question 20

What medications can you use for tx of ED?

Answer 20

Phosphodiesterase-5 Inhibitors (PDE-5-I)

Yohimbine

Question 21

Other interventions for ED?

Answer 21

Vacuum Erection Device (VED)

Medicated Urethral System for Erection (MUSE)

Penile injection

Constriction ring

Penile splint

Penile prosthesis

Penile revascularization

Question 22

PDE5 inhibitiors are contraindicated with…

Answer 22

nitrate use

Question 23

Use of VED?

Answer 23

Cylinder placed over penis
Vacuum created

Increased arterial blood flow into corpora cavernosa (against lowered resistance)

Cylinder removed

Constricting ring placed at base of penis

Question 24

What is Medicated Urethral System for Erection (MUSE)?

Answer 24

Urethral suppository
Alprostadil (Prostaglandin E-1) 125-1000 mcg

Increases intra-cellular c-AMP decreased intracellular calcium –> cavernosal artery vasodilation

Question 25

Use of Penile injection?

Answer 25

injection of vasodilatory meds directly into corpus cavernosum

inject shaft on one side prior to sexual activity

Prostaglandin E1 + Phentolamine + Papaverine (Tri-mix or Triple Agent)

Question 26

Dose limit for penile injection?

Answer 26

no more than 3 doses/wk

Question 27

risks assoc. with penile injection?

Answer 27

pain

infx

bleeding

fibrosis –> curvature (alternate sides)

priapism

Question 28

What is priapism?

Answer 28

EMERGENCY

A persistent penile erection that continues hours beyond sexual stimulation and lasts greater than 4 hours duration

Problem is pain, stasis, hypoxia to cavernosal tissues, acidosis, fibrosis, erectile dysfunction.

Question 29

Tx for priapism?

Answer 29

Placement of 18-19 gauge needle into corpus cavernosum.

Aspiration of cavernosal blood. Infusion of saline. Injection of phenylephrine (vasoconstrictor)

may need surg to create shunt

Question 30

What can constriction ring be use for?

Answer 30

tx for venous leakage

should be easily removed

Question 31

What is a penile splint?

Answer 31

Circumferential ring placed at base of glans (corona)

Attaches to rigid bar going along underside (anterior) of penile shaft.

Bar attaches to a circumferential ring at penile base.

Question 32

Describe penile prosthesis

Answer 32

Surgical implantation of rods into penile shaft to increase rigidity

Non-inflatable and inflatable

Question 33

Describe non-inflatable penile prosthesis?

Answer 33

Two rods, surgically implanted in left and right penile shaft

Can be bent into and out of position of use (“goose-neck lamp”)

Question 34

Describe inflatable penile prosthesis

Answer 34

Two inflatable rods placed in right and left sides of penile shaft

Reservoir placed in abdomen, behind abdominal muscles

Pump in scrotum to transfer fluid from reservoir to rods

Question 35

How should you dose PDE5 inhibitor if pt is also on an alpha blocker?

Answer 35

lowest dose of each

Question 36

ADEs of PDE5 inhibitors?

Answer 36

nasal congestion, facial flushing, HA, dyspepsia, back pain, myalgias, visual changes, priapism

Question 37

What are the 4 different PDE5 inhibitors?

Answer 37

Sildenafil (25-100 mg)
Tadalafil (2.5-20 mg)
Vardenafil (2.5-20 mg)
Avanafil (50-200 mg)

Question 38

When should you dose PDE5 inhibitors?

Answer 38

30-60 minutes before sexual activity

avoid taking after meal

Question 39

Which PDE5 inhibitor is approved for the use of ED and BPH?

Answer 39

Tadalafil