Erectile Dysfunction Flashcards
Normal Male Sex Function Components
- Libido
- Penile Erection
- Orgasm/ejaculation
- Fertilization
Types of Sexual Dysfunction
- Decreased libido
- Erectile dysfunction (impotence)
- Abnormal ejaculation (premature, delayed, retrograde)
- Infertility
Erectile Dysfunction
Failure to achieve penile erection suitable for sexual intercourse
Penile Anatomy
- 2 dorsolateral cylindrical bodies
- Corpora cavernosa
- 1 midventral corpus spongiosum - encloses urethra and expands distally to form glans penis
- Tunica albuinea - thick, fibrous sheath enclosing cavernosa
- All bodies surrounded by deep, fibrous tissue called Buck’s fascia
Penile Circulation
- Cavernosal tissue - spongelike with mesh interconnected cave like spaces
- Lined by vascular endothelium and separated by trabeculae
- Blood supplied by cavernosal arteries (branches of penile artery)
- Three sets of veins - deep, intermediate, and superficial veins
- Deep veins drain the cavernosa and spongiosum
Physiology of Erection
- Sexual stimuli elicits response from CNS to penile nerves and endothelial cells
- ACh = important neurotransmitter
- Cavernous nerves and endothelial cells release NO
- NO stimulates formation of cGMP which causes relaxation of smooth muscle and allows for increased blood flow
- Trabecular spaces expand and erection is achieved
- Expansion compresses the venules to prevent blood from leaving penis
Types of Erections
- Psychogenic - initiated primarily by CNS stimuli received/generated by brain
- Reflexogenic - result of direct stimulation of penis/surrounding tissues
- Noctural - occurs during REM sleep, increases oxygen to penis
ED Factors
- Vascular insufficiency
- Neurogenic - impair cholinergic innervation
- Endocrine - low testosterone or increased prolactin
- Psychological - disease states like depression
ED Etiologies
- Psychogenic - origin from mental and emotional processes
- Organic - medical conditions, structural abnormalities, medications, surgery, trauma, endocrine malfunctions
ALMOST ALL ARE BELIEVED TO BE A COMBO OF THE TWO
Diseases + ED
- Heart disease (CAD)
- Hypertension
- Diabetes
- Depression
- Chronic renal disease
- Prostate cancer
- Neurologic diseases
ED Risk Factors
- Stress
- Lifestyle - smoking, drinking
- Surgery - radical prostatectomy, TURP
- Trauma
- Local disorders of penis
- Medications
Medications + ED
- CV drugs - digoxin
- Diabetic drugs
- Anti-angrogenic agents - spironolactone, cimetidine, ketoconazole
- Anticholinergic agents
- Alpha adrenergic agonists
- Dopamine blockers
- Hypertensive meds - diuretics, B-blockers
- Antidepressants - SSRI, TCA
- NSAIDs
ED Evaluation
- History and physical
- Consider SHIM in patients with risk factors
- Medication history
- Labs
ED + Labs
- Testosterone, prolactin
- Fasting lipid panel
- Fasting blood sugar
- Complete blood count
- Creatinine and urinalysis
- TSH
SHIM
- Five specific questions about sexual health
- Over past 6 months
- Scores =< 21 require further evaluation
ED Affects
- Creates mental stress
- Affects family interactions
- May cause depression, loss of self-esteem, poor self image
ED Treatment Options
- Counseling: primarily psychogenic
- Non-pharm: vacuum erection devices
- Pharm: oral, injectable, intraurethral
- Surgical: implants, vascular surgery
- Treatment should be reserved for patients with documented ED
Primary/Secondary Hypogonadism Symptoms
- Decreased libido
- Malaise
- Loss of muscle strength
- Depressed mood
- Low serum testosterone (300-1100)
PDE5 Inhibitors
- Sildenafil (Viagra), Tadalafil (Cialis), Vardenafil (Levitra)
- Inhibits PDE5, enzyme that breaks down cGMP
- PDE5-I enhances NO effect and allows for cGMP to remain in the body for longer time periods
PDE-I CI
- Organic nitrates use regularly or intermittently in any form (separate S/V by 24 hours, T by 48)
- Resting hypotension (<90/50)
- Retinitis pigmentosa
- Allergic
ED + CV - Low Risk
- Well-controlled HTN
- Mild, stable angina
- Mild CHF (NYHA class I and II)
- Mild valvular disease
ED + CV - Intermediate Risk
- Moderate, stable angina
- MI within 2-8 weeks
- Moderate CHF (NYHA class III)
ED + CV - High Risk
- Unstable angina
- Uncontrolled HTN
- Severe CHF (NYHA Class IV)
- Recent MI/stroke within 2 weeks
- Moderate/severe valvular disease
- High-risk cardiac arrhythmias
- Obstructive cardiac myopathy
Risk Factors + Treatment
- Low: Start PDE5
- Intermediate: CV workup
- High: PDE5 contraindicated
Specific Cautions/CIs for PDE-I
- Vardenafil/Tadalafil: caution when using with alpha-blockers
- Sildenafil: with doses greater than 25 mg, delay alpha-blockers by 4 hours
- Avanafil: should be on stable doses and hemodynamically stable
PDE5-I AE
- Headache
- Dyspepsia
- Flushing
- Rhinitisto light/nasal congestion
- Myalgia and back pressure
- Decreased blood pressure
- Increased sensitivity to light, loss of blue-green color discrimination
- Vision loss
- Hearing loss
PDE5-I Counseling Considerations
- Physician should discuss with patients the potential cardiac risk of sexual activity and symptoms
- Use of organic nitrates in any form
- Painful/long lasting erection (greater than 4 hours)
- Doesn’t protect against STDs
- Engage in sexual stimulation for best response
- Best response on empty stomach
- Avoid alcohol
- Try 5-8 times before declaring failure
- Do NOT combine with any other therapy (including nonpharm)
Additional ED Counseling
- Seek medical attention if sudden vision or hearing loss
- Those with testosterone deficiency may have better results combining PDE5-I and testosterone therapy
Alprostadil
- Synthetic version of prostaglandin E1 (PGE1)
- MoA: augments ACh activity, smooth muscle relaxes, blood flow increases, corpora cavernosa enlargesand preventing blood outflow
- Results in erection without sexual stimulation
- Available as both injection and intraurethral pellet
- Limit to once a day or three times per week
Alprostadil SE
- Nausea
- Flushing
- Hypotension
- Penile pain
- Penile/urethral injury
- MUSE could cause vaginal burning or itching
- Permanent fibrosis and dysfunction (1-15%)
Alprostadil CI
- Increased risk for priapism, sick cell disease, leukemia, multiple myeloma
- Risk from bleeding at injection site - anticoagulation
Vacuum Erection Devices
- Therapeutic option
- All consist of cylinder, vacuum pump, constriction ring
- Ring prevents venous drainage and maintains ridigity
Reasons to D/C Penis Pump
- Lack of spontaneity
- Difficult to use
- Discomfort
- Delayed onset of erection
Penis Pump Safety
- Most complications are minor: petechiae, numbness, ejaculatory discomfort
- Ischemia - if ring is used for long periods
- Avoid in those using anticoagulants
Penile Implants
- Surgical prosthetic devices
- Semirigid (always erect) and inflatable options
- Used when other therapies fail
- Destroys corporal tissue
- Inflatable devices are prone to mechanical failure
Implant Complications
- Infection
- Erosion
- Mechanical failure
- Repeated surgery to remove or replace implant
Vascular Surgery
- Vascular problems are key causes in many ED patients
- Damage can be arterial or venous system
- Venous surgery NOT recommended
Patient Education/Counseling
- Treat underlying cause
- Non-drug approaches: stop smoking/drinking, diet, exercise
- Identify/replace offending drugs if possible
- Be private, empathetic, and respect preferences