11_10 Exam 7 - Erectile Dysfunction

Front 1

Describe the usual anatomy and physiology of a penile erection including the systems that are involved.

Back 1

arousal - ACh -> NO, cGMP, cAMP -> decr intracell Ca = sm muscle relaxation and vasodilation

arteriole blood into corpora sinusoids = swelling and elongation

elongation prolonged by compression of veins from corpora

vasoconstriction of c. cavernosa = flaccid again

Front 2

Discuss the common pathophysiology associated with erectile dysfunction.

Back 2

Psychogenic erectile dysfunction
–
Patients are unable to effectively respond to sexual stimuli
•
Organic erectile dysfunction
–
Vascular etiologies
•
Compromised vascular flow
–
Peripheral vascular disease, atherosclerosis, hypertension
–
Neurologic etiologies
•
Impair conduction to/from brain: Spinal cord injury, stroke
•
Impair conduction to penile vasculature: Diabetes
–
Hormonal etiologies
•
Reduced testosterone
–
Hypogonadism
•
Cigarette smoking, excessive EtOH, illicit drug use appear to increase the risk of EDËøû•‡

Front 3

Identify groups of medications and their likely mechanisms that are known to cause erectile dysfunction./

Back 3

Anticholinergics
DA ag = incr prolactin which Decr testosterone production from testes

Estrogen/antiandrogen
decr testosterone-mediated effects on libido

CNS depressants
benzo, barbs, opioids
=decr perception of stimuli

Agents that decr arterial blood
BB, diuretics, central sympatholytics
=decr blood to corpora

Front 4

On average, ED symptoms present ____ years earlier than CAD symptoms2

Back 4

3

Front 5

List the general therapeutic approach to the treatment of erectile dysfunction.

Back 5

General approach
–
Identify and manage underlying CAUSES
•
Testosterone replacement in hypogonadism
•
Psychogenic cases may need to be addressed with non-pharmacologic counseling
–
Identify and manage RISK FACTORS
–
Initiate specific TXS for erectile dysfunction
•
Involving partners in the treatment plan increases likelihood of treatment success

Front 6

Discuss the role of cardiovascular disease history in determining appropriate candidates for erectile dysfunction therapies (ie. PDE5i treatment).

Back 6

?

Front 7

Discuss the role of testosterone replacement in the treatment of erectile dysfunction.

Back 7

Testosterone Replacement

ONLY if pt dx w/hypogonad
=decr serum lvl and libido
no addtl benefit from >normal serum lvls testosterone
Patients should be tried on a particular dose for 2 to 3 months when evaluating overall efficacy

Adv Es =
Na retention = wt gain
decr HDL

Front 8

Testosterone Replacement
Oral agents

Back 8

Higher incidence of hepatotoxicity „»generally not used for sexual dysfunction secondary to hypogonadism/

Front 9

Testosterone Replacement
Topical

Back 9

Topical products
•
Patches or gels
•
More expensive than injectable products

Front 10

Testosterone Replacement
Injectable products (Intramuscular)

Back 10

Propionate salt „»3 times per week injections

Cypionate or enanthate salts „every 2 to 6 week injectionsm

Front 11

Vacuum Erection Device

ease of use
safety (adv eff)
onset of action.

Back 11

easy
minimal AdvEff
SLOW onset
(all others are fast)

Front 12

PDE5 Inhibitors

ease of use
safety
onset of action.

Back 12

Fairly easy to use
Systemic AdvEffs
fast

Front 13

Intracavernosal Alprostadil

ease of use
safety
onset of action.

Back 13

Moderate (injections)
local rxn
fast

Front 14

Intraurethral Alprostadil

ease of use
safety
onset of action.

Back 14

difficult
localized rxn
fast

Front 15

Surgical prostheses

ease of use
safety
onset of action.

Back 15

Easy to use once implantedlY
surgical infxn
fast

Front 16

Highlight the key differences between the available phosphodiesterase type 5 (PDE5) inhibitors.

PDE inhibited
fatty meal decr abs?
time to peak
duration

Back 16

silden varden tadala
PDE 6 6 11
fatty meal Y Y
peak time .5-1 .7-.9 2h
duration 4 4 24-36

Front 17

PDE5 inhs
MoA
3 ex drugs:

Back 17

Decrease catabolism of cGMP,Y
–
Sildenafil (Viagra)
Tadalafil (Cialis)
Vardenafil (Levitra)

Front 18

What conditions = intermediate risk where...

Patient should undergo complete cardiovascular workup and treadmill stress test to determine tolerance to increased myocardial energy consumption associated with increased sexual activity

Back 18

3 RFs for CVD
MI/Strok in last 6wks
Moderate CHF

Front 19

When are PDE5's CI? What pt. conditions?

Back 19

Has unstable or symptomatic angina, despite treatment
Has uncontrolled hypertension
Has severe CHF (NYHA class III or IV)
Had a recent MI or stroke within past 2 weeks
Has moderate or severe valvular heart disease
Has high-risk cardiac arrhythmias
Has obstructive hypertrophic cardiomyopathy

Front 20

PDE5i Adverse Effects/Precautions for each of the 3 drugs

Back 20

S Varden Tadal
decr BP Y Y N
viz change BLUE min min
low back N N Y 7-30%
avoid nitrates 24h 24h 48h after dose
class effect: Headache, facial flushing, dyspepsia,
nasal congestion, dizziness, priapism, SUDDEN HEARING LOSS

Front 21

PDE-5 inhibitor treatment failures
primarily due to

Back 21

improper use
41% of failures

Front 22

Alprostadil Intracavernosal
MOA
products and diffs
AdvEff

Back 22

•MOA: Prostaglandin E1 stimulates cAMP, thus leading to increased smooth muscle relaxation and vasodilation in the corpora
•
Products
Caverject
•Patients draw up dose (vial w/ diluent or aqueous)
–
Caverject Impulse (pre-filled syringes)
–
Edex (cartridge w/ reusable device)

Local reactions
•
Pain on injection and/or during the erection (10 –44%)
•
Fibrous plaque formation ( 2 to 12 %)
•
Hematoma
•
Infection
–
Priapism ( 1 to 15%)
•
Dose-related
–
Importance of dose titration during initiation of therapy
»
Can be a VERY time intensive process in the Urologist office!
–
Systemic hypotension (dizziness/syncope)
•
Usually only if doses exceed 20 mcg

Front 23

Storage:
Caverject (powder)
Caverject (aq)
Caverject Impulse (prefilled syringe)

Back 23

powder-vials-REFER, dispense at room temp (3 mo exp date)

aq-FREEZ (7 days exp)
room temperature

Front 24

Alprostadil Intraurethral (MUSE)
MOA
EFF comp to intracavernosal alprostadil
Adverse effects

Back 24

Absorbed from the urethra into the corpus spongiosum and then in the corpus cavernosum

–
Urethral pain (25 –30%); 3% actually from insertion (?)
–
Vaginalburning, itching, or pain in partners
–
Syncope/dizziness (with larger doses)Y

Front 25

Additional Alprostadil Pearls

Intracavernosal
–
Inject into proximal __/__ of penis
Avoid visible ____
Rotate _____ ______
Use no more than once/___ hours or ____ times weekly

Back 25

1/3
visible veins
inj site
1/24h or 3x wkly

Front 26

Additional Alprostadil Pearls

Intraurethral
____ prior to administration
_____ _____ _____ in an upright position between hands for 10 seconds to distribute the medication
–
Don't.... for 10 minutes after administration
–
Use no more than ____/24 hours

Back 26

urinate prior
roll the penis
lie down
twice

Front 27

PPP (“triple P”) mixture =

Back 27

prostaglandin E1 + papaverine + phentolamine

Front 28

PRIAPISM
Risk for tissue hypoxemia when > ____ hour

Back 28

4

Front 29

Penile Prosthesis
Adverse effectsis

Back 29

Surgical infections
–
Mechanical failure
–
Erosion of implant

Front 30

PDE-5 inhibitor treatment failures

Back 30

pde5 inh failure =
refer to specialist or assess failure
check non-compliance