Campbell`s Chapter 22 - Detroit Medical Center
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Transcript Campbell`s Chapter 22 - Detroit Medical Center
Evaluation and Nonsurgical
Management of Erectile Dysfunction
and Premature Ejaculation
Brent Zamzow DO
January 14, 2008
ED - Historical
Before 1970 – Psychotherapy
1970’s - Penile prosthesis & psychotherapy, sleep lab
1980’s - Yohimbine, intracavernous & transurethral
therapy, vacuum device, testosterone, ultrasound
1990’s to present - oral PDE-5 inhibitors
ED treatment
Psychologist → Urologist → Primary Care
ED - Historical
1999 - 1st International Consultation on Sexual
Medicine (ICSM)
ED redefined as consistent or recurrent inability to
attain and/or maintain penile erection sufficient for
sexual performance
ED is a symptom of many medical problems
requires physician involvement
internet prescribing condemned
Goal-directed approach
ED - Historical
2nd ICSM - 2004
Patient-centered & evidence-based
See illness through patient’s eyes
Holistic approach - biologic, psychologic & social
aspects
Flexible & individualized approach
Let patient choose his best therapy
3rd ICSM - July 10-13, 2009
Self-Administered Questionnaires
International Index of Erectile Function (IIEF)
most common questionnaire
addresses erectile function, orgasmic function, desire,
intercourse satisfaction, overall satisfaction
Male Sexual Function Scale
2nd ICSM
Doesn’t take into account partner
History Taking
Medical
atherosclerosis, DM, depression
organic vs. psychogenic
medications, pelvic surgery?, trauma?
Sexual
severity, onset, duration
Psychosocial
social, occupational, family, financial
Don’t assume everyone’s involved in monogamous,
heterosexual relationship
Exam & Labs
Physical Exam
General screening for risk factors
body habitus, cardiovascular, neurologic, genital
Labs
Fasting glucose, lipids, hormonal profile, thyroid
function
Findings
Educate patient on modifiable risk factors
stress, marital conflict, smoking, EtOH, obesity, bicycle
riding, prescription drugs
ED Treatment Options
Vascular Evaluation
Goal - diagnose & quantify arterial & veno-occlusive
dysfunction
Options:
Combined intracavernous injection & stimulation (CIS)
Duplex ultrasound
Dynamic infusion cavernosometry & cavernosography
(DICC)
Selective penile angiography
Evaluation of Penile Blood Flow
st
1 line
Combined Intracavernous Injection & Stimulation
(CIS)
Inject vasodilator, stimulate, assess
Most commonly performed diagnostic procedure for ED
Bypasses neurologic & hormonal influences to evaluate
vascular status
Use:
alprostodil 10-20ug
papaverine & phentolamine (Bimix 0.3 mL)
Trimix 0.3 mL
27 or 29g needle, compress for 5 min after injection
st
1
line - CIS
Normal results = normal venous occlusion
False negative up to 20% w/ borderline arterial flow
Evaluation of Penile Blood Flow
2nd Line
Duplex Ultrasonography
Penile blood flow study (CIS & blood flow measurement
by US) is most reliable & least invasive evidence based
assessment of ED
Red = towards probe
Blue = away from probe
Can visualize dorsal & cavernous arteries in real time
Can diagnose high flow priapism
nd
2
line - Ultrasound
Technique
Measure flow velocities 5-10 min after injection
Rate erectile quality
Look at both cavernous arteries & diameters
Asymmetric cavernous arterial flow >10cm/s or reversal
of flow across a collateral may mean atherosclerotic
lesion
nd
2
line - Ultrasound
Doppler Waveform
nd
2
line - Ultrasound
Peak Systolic Velocity (PSV)
PSV < 25 correlates with abnormal pudendal
arteriography
Severe unilateral arterial insufficiency >10 cm/s
asymmetry
Severe vascular ED, diameter increase is <75%, diameter
rarely exceeds 0.7 mm
Be aware of variant vessel anatomy
nd
2
line - Ultrasound
Veno-occlusive Dysfuntion
Need to trap blood & limit venous outflow
Venogenic impotence
High systolic flow (>25 cm/s)
Persistent end-diastolic flow (EDV) (>5 cm/s)
Resistive Index (RI)
RI = PSV – EDV/PSV
Measure 20 min after injection & stimulation
RI > 0.9 normal
RI < 0.75 venous leakage
ISCM Recommendations on US
Intracavernosal injection with color duplex Doppler
ultrasound
Most informative diagnostic test
Least invasive for vascular ED, high vs. low flow
priapism, Peyronie’s plaque
Useful measurements
PSV, cavernous artery diameter, EDV, RI
PSV <25 = severe cavernous artery insufficiency
PSV >35 = normal inflow
Negative relationship between age & PSV
Evaluation of Penile Blood Flow
3rd line
Cavernous arterial occlusion pressure
Basically penile blood pressure measurement – 1989
Technique
Inject vasodilator
infuse saline into corpora to get pressure > systolic BP
apply Doppler to penile base
Pressure when cavernous arterial flow becomes detectable is
cavernous artery systolic occlusion pressure (CASOP)
Gradient between cavernous & brachial artery pressure
<35 & equal pressure on L & R is normal
rd
3
line – Penile Blood Flow
Pharmacologic Arteriography
Technique
Inject vasodilator
Cannulate internal pudendal artery
Inject contrast
Look at anatomy of iliac, internal pudendal, penile arteries
Aberrant anatomy in 50% of normal volunteers
Useful for anatomy, not function
Indication:
Young pt w/ ED due to traumatic arterial disruption or
perineal compression injury. Essential for planning
reconstruction
rd
3
line – Penile Blood Flow
Pharmacologic Cavernosometry & Cavernosography
Cavernosometry
Saline infusion while monitoring intracavernous pressure
Assesses penile outflow
Cavernosography
Infusion of contrast into corpora after vasodilator induced
erection
Good for young men who may be candidates for penile
vascular operations
Historical & Investigational
Penile Brachial Pressure Index
Inaccurate
Penile Plethysmography
Penile pulse volume recording
Infrared Spectrophotometry
Radioisotopic Penography
MRA
Cavernous Smooth Muscle Content
Nocturnal Penile Tumescence (NPT)
80% NPT during REM sleep
Total tumescence time
20% of night at puberty
Adults – 27 minutes/night
RigiScan - 1985
Monitors radial rigidity, tumescence, number, duration of
erectile events
Portable – can use at home
Can record 3 different nights up to 10 hrs each
Results
Radial rigidity >70% = good erection
<40% = flaccid penis
Normal = 3-6 erections/night, 10-15 minutes per episode
NPT
NEVA device
Uses electrobioimpedance to assess volumetric changes
in penis during nocturnal erections
Undetectable alternating current from glans to hip
electrodes
Penile base electrode measures impedance & changes in
penile length
Mean volume change in controls = 213% increase (14.4
mL)
NPT Summary
Freedom from psychological influences & its ability to detect
sleep-related abnormalities
Full erection = neurovascular axis is functionally intact & cause is
likely psychogenic
Disadvantages
Age dependent
Costly
Not recommended as routine test for ED
Indications:
Suspected sleep disorder
Obscure cause
Nonresponse to therapy
Planned surgical treatment
Legally sensitive case
Measurement of drug effects in placebo-controlled drug trials
Suspected psychogenic cause
Psychological Evaluation
ED associated with:
Anxiety
Depressive symptoms
Low self-esteem
Negative outlook on life
Emotional stress
History of sexual coercion
General vs. Situational?
Primary vs. Acquired
Substance abuse, psychiatric illness
Noncoital erections
?Masturbatory, nocturnal, morning
Hormonal Evaluation
Hypogonadism increases with age
Decrease or absence of hormonal secretion from the
gonads in men
Draw testosterone between 8-11am
For screening – total testosterone
If testosterone low or low-normal
Confirm with 2nd draw + LH + prolactin
Testosterone
Men produce 4-8 mg/day in pulsatile manner
Peaks in morning, nadir in evening
Converts to DHT by 5α-reductase in skin, liver, prostate
Metabolized to estradiol by aromatase in brain, fat, liver, testes
2% unbound – free testosterone
30% bound to SHBG
Rest bound to albumin & other serum proteins
Bioavailable testosterone = free + albumin bound
SHBG made by liver – downregulated by androgens, upregulated
by estrogens
Estrogens, thyroid hormone, aging increase serum SHBG &
decrease bioavailable testosterone
Exogenous androgens, growth hormone, obesity depresses SHBG
& increases free testosterone
Lifestyle Change & ED
Obesity
Decreased BMI = improvement in ED
Physical Activity
Sedentary = highest risk
Cigarette Smoking
Statin to lower cholesterol may improve ED
Long distance bicycle riding
No Effect
Education level
Marital status
Urban vs. Rural
Coffee
EtOH
Medications & ED
Nonspecific alpha-blockers have most severe effect on erectile
function
Methyldopa & Reserpine
Thiazide diuretics
Spironolactone interferes with testosterone synthesis
SSRI’s – ED & ejaculation problems
Calcium channel blockers & ACE inhibitors don’t cause ED
Alpha-1 blocker is protective
Doxazosin reduces incidence of ED
Herbal Supplements for ED
25-50% placebo response
Acupuncture – psychogenic ED
Androstenedione – may benefit men w/ low
testosterone, lowers HDL 10%
Ginko biloba – may have blood-thinning effect
Korean red ginseng – may benefit
L-Arginine – precursor to Nitric Oxide, may lower BP
Yohimbine – most supplements contain little or none,
can have serious side effects
Zinc – good if low zinc, can be immunosuppressive
Testosterone Therapy
Injectable (IM)
Least expensive
200-250mg q2wks
Do not replicate normal circadian rhythm
Testosterone “rush” for 72 hrs, then low by 10-12 days
Transdermal
Can simulate normal circadian levels if applied in AM
Patch – 2.5-5 mg/day
Applied daily to arm, back, or upper butocks
Side effects – itching, chronic irritation, contact dermatitis
Gel – 50, 75, or 100 mg packs
Applied daily to arms, abdomen, or shoulders
Wash hands after application
Pellet – 75mg/pellet
2-6 pellets implanted subQ q3-6months
Buccal – 30mg tablet BID
Oral – 200mg/d
Become metabolically inactive after 1st pass through liver
Large doses toxic to liver
Hormonal Therapy
DHT
Cannot be aromatized to estradiol – pure androgen
Good for hypogonadal men w/ gynecomastia, boys w/
delayed puberty
Dehydroepiandrosterone (DHEA)
Controversial
End Points
General well-being, mood, sexual interest, sexual
activity
Adverse Effects of Testosterone
Replacement
Infertility
Suppresses LH, FSH
Breast tenderness & gynecomastia
Erythrocytosis
Mean Hct increases from 42-47% after 3 months
Induce or worsen sleep apnea
May increase PSA
? Exacerbates prostate cancer
Prostate or breast cancer = contraindication
Monitoring
DRE & PSA q6months
Periodic H&H, LFT’s, lipid profile
Efficacy of testosterone determined by clinical response
If hyperprolactinemia – testosterone does not improve sexual function
Phosphodiesterase Type-5
Inhibitors
Sildenafil (Viagra)
FDA approved 1998
Vardenafil (Levitra)
FDA approved 8/2003
Tadalafil (Cialis)
FDA approved 11/2003
Arousal Pathway
Sexual arousal stimulates NO release at penile nerve
endings
NO diffuses into vascular & cavernous smooth muscle
cells
Stimulation of guanylyl cyclase & elevation of cGMP
Hyperpolarization & lowers cytoplasmic calcium
Smooth muscle relaxation & erection
PDE-5 inhibitors potentiate NO’s effect
Do not increase NO levels
Need sexual stimulation for PDE-5 inhibitors to work
PDE-5 Inhibitors
Sildenafil & Vardenafil cross-react slightly w/ PDE-6
? Reason for visual disturbances
Tadalafil minimally cross-reacts with PDE-11
Consequences unknown
Other side effects:
Headache, flushing, low BP, dyspepsia due to PDE-5
inhibition in vascular or GI smooth muscle
Sildenafil 20mg TID FDA approved in 2005 for
pulmonary HTN
Sildenaf Vardenafi
il
l
Tadalafil
Onset of Action
15 min - 1 hr
15 min – 1 hr
15 min – 2 hr
Half-life
3-5 hr
4-5 hr
17.5 hr
Bioavailability
40%
15%
Not tested
Fatty Food
↓↓
Absorption
↓↓ Absorption
No effect
HA, flushing,
dyspepsia
Yes
Yes
Yes
Bachache, Myalgia
Rare
Rare
Yes
Blurred/Blue vision
Yes
Rare
Rare
Precaution w/
antiarrhythmics
No
Yes
No
Contraindication w/
nitrates
Yes
Yes
Yes
PDE-5 Inhibitors
Very effective at enhancing erectile function
Good for different patient subgroups, ED causes, outcomes
measured
Difficult to Treat Patients
All effective in ED + DM
All improve ED following prostate cancer
Nerve sparing pts respond better
Daily PDE-5 inhibitor may be beneficial
Sildenafil + testosterone if ED & low testosterone
Cumulative probability of success increases w/ 1st 9-10 attempts
Tadalafil – less planning, longer half-life, more convenient for
PDE-5 Inhibitors
Side effects peak at first 2wks of use
Package Insert Warnings
MI within 90 days
Unstable angina, or angina w/ intercourse
NY Heart Association class II or greater heart failure in last 6
months
Uncontrolled arrhythmias, hypotension (<90/50), or HTN
(>170/100)
Stroke in past 6 months
Known hereditary degenerative retinal disorders, including retinitis
pigmentosa
Tendency to develop priapism (sickle cell, anemia, leukemia)
Impairs metabolic breakdown
Ketoconazole, itraconazole, protease inhibitors (ritonavir) – lower
dose
PDE-5 Inhibitors
Recommended starting dose
50mg sildenafil
10mg vardenafil & tadalafil
Cardiovascular safety
They do not worsen cardiac events
Vardenafil not recommended w/ type IA antiarrythmics (quinidine
or procainamide) or type 3 (sotalol or amiodarone), or congenital
prolonged QT syndrome
Use w/ caution in aortic stenosis, left ventricular outflow
obstruction, hypotension, hypovolemia due to vasodilator effects
Nitrates – absolute contraindication
Use >2 wks ago, not contraindication
Don’t take nitrate for at least 24 hrs after (48hrs for tadalafil)
Alpha-blocker – use caution due to vasodilation & hypotension
Intracavernous Injection
1983 AUA meeting, Brindley personally demonstrated erection
after injection of phenoxybenzamine
1985 – papaverine & phentolamine injection use reported
Papaverine
Isolated from opium poppy
Inhibitory effect on PDE, increased cAMP & cGMP, blocks calcium
channels
1-2 hr half-life
Good
Low cost
Stable at room temp
Bad
Priapism (up to 35%)
Corporal fibrosis (1-33%) due to acidity
<55% effective
Not FDA approved
Intracavernosal Injection
Phentolamine (alpha1 & alpha2-antagonist) (Regitine)
Side effects
Hypotension
Reflex tachycardia
Nasal congestion
GI upset
30 min half-life
Increases corporal blood flow, but does not cause
significant increase in intracavernous pressure
Intracavernosal Injection
Alprostadil (Caverject & Edex 2-40mcg) - Prostaglandin E1
Exogenous form of a naturally occurring fatty acid
Causes smooth muscle relaxation, vasodilation, inhibition of
platelet aggregation by elevating cAMP
Metabolized by prostaglandin-15-hydroxydehydrogenase in corpora
cavernosa
96% locally metabolized after 60 min
Side effects
Pain at injection site or during erection
Hematoma
Priapism
Much lower incidence of fibrosis
Once reconstituted into liquid from powder, has shortened half-life
if not refrigerated
Intracavernosal Injection
Combinations
Papaverine + Phentolamine
Papaverine + Phentolamine + Alprostadil
Lower incidence of painful erection
As effective as alprostadil alone
Good for failed therapy or painful erection w/ PGE1
Serious side effects
Priapism
Alprostadil 1.3%
Papaverine 10%
Papaverine/phentolamine 7%
Fibrosis
Alprostadil 1%
Papaverine 12%
Papaverine/phentolamine 9%
Intracavernosal Injection
Contraindications
Sickle cell
Schizophrenia
Other severe psychiatric disorders
Severe systemic illness
If on anticoagulant, compress injection site for 7-10 min
Poor manual dexterity – have partner inject
Intraurethral Therapy
Alprostadil (Muse)
Absorbed in spongiosum & transported to cavernosa
through venous channels (circumflex & emissary veins)
3mm x 1mm pellet
500 mcg Muse = 10 mcg injected alprostadil
2/3 respond
Side effects
Penile pain/dull ache in penis, scrotum, legs
Central Acting Drugs
Yohimbine
Alpha2-antagonist from bark of yohim tree
Good for psychogenic ED
Side effects
GI upset, anxiety, HA, agitation, palpitations, HTN
AUA stance – no efficacy of yohimbine over placebo with
organic ED
Trazadone
Apomorphine
Dopaminergic agonist
Vacuum Constriction Device
Plastic cylinder connected to vacuum-generating
source
Place constriction ring after engorgement
Remove ring within 30 min
Satisfaction rate 68-83%
Premature Ejaculation (PE)
DSM-IV
Persistent or recurrent ejaculation with minimal
stimulation before, on, or shortly after penetration and
before the person wishes it
Short ejaculatory latency, lack of control, sexual
dissatisfaction
Latency <2 min suggests possible PE
Excludes PE secondary to EtOH, substance abuse,
medication
Premature Ejaculation
Etiology
Penile Hypersensitivity
5-Hydroxytryptamine-Receptor Sensitivity
Hyperarousability
Hyperexcitable ejaculatory reflex
Genetic predisposition
Psychogenic
Poor control techniques
Early sexual experience
Anxiety
Infrequent sex
Premature Ejaculation
Treatment
Psychological/Behavioral
Drugs
SSRI’s
Paroxetine (Paxil) exerts strongest ejaculatory delay
Daily or 3-4 hrs prior to intercourse
Sertraline (Zoloft), Fluoxetine (Prozac)
Side effects
Fatigue, yawning, nausea, loose stool, perspiration
Ejaculatory delay starts to occur at end of 1st or 2nd week
Nonselective Serotonin Reuptake Inhibitor
Clomipramine (Anafranil)
Daily or 3-4 hrs before intercourse
Other PE Treatment
Topical anesthetic
Effective at retarding ejaculation
PDE-5 Inhibitors
Unlikely to have role
END