Erectile dysfunction

Question 1

Relationship btwn erectile dysfxn and other medical conditions

Answer 1

• 85% of erectile dysfxn caused by a physical problem
• Common causes of erectile dysfxn: vascular disease, iatrogenic factors, congenital abnormalities, drugs, neuropathy, psychological processes, peyronie’s disease
• Associations btwn ED and other medical conditions: aging, HTN, DM, BPH, CVD, smoking, depression, etoh, trauma/surgery, chronic neuro diseases, endocinopathy, drugs

Question 2

How an erection normally occurs

Answer 2

• In flaccid state the penis is under venous O2 tension and pressure
• Erection transforms penis into arterial organ
• Vasodilation mediated by NO and cGMP following activation of cholinergic and NANC (nonadrenergic noncholinergic) fibers
• PGE relaxes corpus cavernosum
• 4 components to an erection: desire (hormones), coordination (brain/SC), signal (nerves), erection (blood flow)

Question 3

Dysfxns in erection control

Answer 3

• Problems w/ desire: due to loss of hormones (various organic causes, surgery, drugs) and/or stress
• Problems w/ brain/SC coordination: tumors, stroke, parkinson’s disease, trauma, MS, drugs
• Problems w/ pelvic nerve signals: surgery, smoking, DM
• Problems w/ blood flow: atherosclerosis, HTN, DM, smoking, heart disease

Question 4

Vascular causes to ED

Answer 4

• HTN, DL, and DM all contribute to atherosclerosis and impairment of endothelium-dependent relaxation of arterioles
• Arterial stenosis from atherosclerosis and impaired vasodilation together lead to arterial insufficiency and reduced inflow to the penis
• SmM atrophy/fibrosis and impaired relaxation of the corpora cavernosa lead to coporo-veno occlusive disease and excessive outflow
• Excessive outflow along w/ reduced inflow of blood to penis results in a constitutively flaccid state

Question 5

Work-up for ED

Answer 5

• Hx and asking about risk factors (HTN, DL, smoking, etoh, DM, CVD, depression, endocrine d/os)
• Asking about drugs associated w/ ED: etoh, BBs, smoking, estrogens/antiandrogens, anticholinergics, antidepressants, antihypertensive agents, psychotropic drugs
• PE: assess secondary sex characteristics, femoral pulses, focused neuro exam, prostate
• Labs: morning serum T, prolactin, CBC, urinalysis, Cr, glc, lipids, TSH

Question 6

Rx options for ED

Answer 6

• Lifestyle modification: diet and exercise, stress relief, quit smoking/drinking/drugs, possibly psychosexual counseling
• Hormonal replacement
• Oral meds (PDE5 inhibitors, increase cGMP and thus NO): viagra, cialis (first line)
• Must have some stimulation to work, contraindicated in pts on nitrates, cannot drink etoh
• Pumps/constriction devices
• Injectables (second line): PGE, phentolamine (a adrenergic antagonist)
• Both forms relax SmM in the deep artery (poor long term tolerability
• Vascular surgery/implants