Erectile Dysfunction Flashcards
Define: erectile dysfunction
Inability to attain &/or maintain erection sufficient for satisfactory sexual performance
What 2 processes are involved in the normal physiology of erections?
- Relaxation of SM of cavernosal artery –> increased inflow of blood to corpora cavernosa
- Increased venous outflow resistance –> decreased outflow
What occurs during relaxation of SM of cavernosal arterial wall?
- PNS nerves release NO
- Increased cGMP & cAMP in cells surrounding cavernosal arteries
- Decreased intracellular Ca
- SM relaxation, vasodilation
- Wider diameter of artery
- Greater inflow of blood into corpora cavernosa
What occurs during increased venous outflow resistance?
High inflow into corpora cavernosa –> CC expands & compresses venous sinuses
Decreased outflow of blood –> sustained erection
What causes ED?
vasculogenic
neuro
psycho
endocrine
meds
disease
What are 2 examples of vasculogenic causes of ED?
Arterial inflow problem
Venous outflow problem
What is an example of a neuro cause of ED?
Prostatectomy
What are examples of psycho causes of ED?
Depression
Stress
Anxiety
Psych disorders
What are examples of endocrine causes of ED?
Hyperprolactinemia
Thyroid d/o
Sex hormone binding globulin
Hypogonadism
What type of meds can cause ED?
Anti-HTN
Antidepressant, antipsychotic
Meds that reduce testosterone
What disease states could cause ED?
Renal insufficiency, DM, hepatic disease
Prostatectomy, cystectomy
Pelvic or penile fx
What scale should you include in your sexual history for ED?
IIEF Scale
Int. Index of Erectile Fxn
What do you want to look for or include when examining a pt w/ potential ED?
Gynecomastia, galactorrhea, visual field defects
Check circulation
External genital exam
Testosterone (if decr libido)
Prolactin (if indicated)
Nocturnal penile tumescence
“postage stamp”
What imaging and procedures should be performed for ED?
Penile duplex doppler sonography
Cavernosometry/cavernosography
How do you tx ED?
- Determine if CV status is appropriate for sex
- Smoking cessation
- Control wt & alcohol
- Possible change of med
- Treat medical condition
What are specific tx options for ED?
- PDE5 inhibitors
- Yohimbine
- Vacuum erection device
- MUSE
- penile injection
- constriction ring
- splint
- prosthesis
- revascularization
Describe detumescence
PDE5 decreases amt of cGMP –> decreased flow into penis
What is the MOA of PDE5 inhibitors?
Block PDE5, permitting cGMP to continues to exert vasodilatory effect
Prolongs erection
What are ADEs of PDE5 inhibitors?
Congestion, flushing, HA, dyspepsia, back pain/myalgia
Visual changes, loss of vision
Priapism
What are 4 names of PDE5 inhibitors?
Sildenafil
Tadalafil
Vardenafil
Avanafil
When should you take PDE5 inhibitors? What should you avoid taking them w/?
- Take 30-60 mins before sex along w/ physical stimulation
- Avoid after meal
Which PDE5 inhibitor has the longest half life?
Tadalafil
Stays in system for 36hrs
What are risks of penile injection?
Pain Infection Bleeding Fibrosis --> curvature Priapism
What is priapism?
Persistent penile erection that continues hrs beyond sexual stimulation & lasts > 4 hrs
Emergency!
How do you tx priapism?
Placement of 18-19 gauge needle into corpus cavernosum.
Aspiration of cavernosal blood.
Infusion of saline.
Injection of phenylephrine
Shunt
What is the goal of tx of priapism?
prevent fibrosis, loss of cavernosal tissue, & recurrent priapism
What can you use to treat venous leakage?
Constriction ring
What type of tx is indicated for focal arterial occlusion of cavernosal artery?
Penile revascularization
