ED Flashcards
What is ED
Inability to attain or maintain an erection sufficient for sexual performance
Affects 52% of men 40+
How does a normal erection occur
Relaxation of smooth muscle in cavernosal artery= increased inflow of blood into corpus carvernosa
Increased venous outflow resistance= decreased outflow
What is the physiology behind attaining a normal erection
PNS releases nitric oxide Increased cGMP/cAMP Decreased intracellular calcium smooth muscle relaxation/ vasodilation greater inflow of blood into cavernosa
(very similar to what B3 agonists do in UUI!)
What is the physiology behind maintaining a normal erection
High inflow into cavernosa causes expansion= compression of venous sinuses
Decreased outflow of blood via venous system
What are vasculogenic causes of ED (MCC)
Arterial inflow problem
Venous outflow problem
What are neurogenic causes of ED
Prostatectomy (2 nerves run very close to the prostate and can be damaged in surgery)
What are psychogenic causes of ED
Depression, stress, anxiety, psych d/o
What are endocrine causes of ED
Hyperprolactinemia (PRL suppresses testosterone)
Thyroid d/o
Hypogonadism (sex hormone binding globulin)
What medications can cause ED
Anti-HTN (BB, thiazide, clonidine, methyldopa)
Antidepressants/psychotics (TCA, MAOI, lithium, phenothiazine)
Sedatives, anticholinergics, Phenytoin, alcohol, tobacco
What medications can reduce testosterone and secondarily cause ED
Cimetidine, spironalactone, ketoconazole, LHRH agonists (leuprolide), non steroidal anti androgens (flutamide, biclumatide), Estrogens
What disease states can cause ED
chronic renal insufficiency
DM
chronic hepatic disease
Neurologic, atherosclerotic, endocrine dz
What trauma can cause ED
Pelvic Fx Penile Fx (tunica vaginalis can snap 2/2 stiffness when erect)
What sexual history is important to ask with a CC of ED
onset, rigidity, duration Morning erections (reflex- when the bladder gets full, erection) Libido Relationship PReformance anxiety/stress Curvature (Peyronie's) IIEF scale
On PE for ED complaint it is important to assess
Circulaiton
Gynecomastia, galactorrhea, visual field deficit
External genitalia exam (penis and testes)
What labs could you check with a CC of ED
Testosterone (if decreased libido, check total and bioavailable testosterone between 7-11 AM)
PRL if indicated
Nocturnal penile tumescence (BP cuff around penis that measurea how many times per night the penis gets erect; normal is a few)
What is Penile duplex doppler sonography
test for ARTERY insufficiency
inject vasoactive med into cavernosa to measure arterial flow and diameter
What is Cavernosometry
test for VENOUS leak
inject vasoactive med into cavernosa- then use needle for inflow of saline and measure rate of inflow of saline required to maintain erection
General Tx of ED can include (before meds, etc.)
Is CV status appropriate for sex? Smoking cessation weight control alcohol change meds if needed treat medical conditions
Other Tx for ED include
Yohimbine PDE5 inhibitors VED MUSE (medicated urethral system for erection) Penile injection constriction ring penile splint penile prosthesis penile revascularization
PDE5-I are contraindicated with
Nitrate use!
can cause severe orthostatic hypotension
*Use caution with alpha blockers (tamulosin, alfuzosin); use lowest dose of each and separate doses
What is the normal role of PDE5
PDE5 decreases amount of cGMP= decreased blood flow to penis= Detumescence
What is the MOA of PDE5-Inhibitors
Block PDE5= cGMP can continue to have vasodilatory effect
Erection is prolonged
ADE of PDE5-I include
Nasal congestion facial flushing HA dyspepsia back pain/myalgias visual changes (blue halo) Non-arteritic ischeimc optic neuropathy priapism
What are the PDE5 inhibitors
Sildenafil (viagra)
Tadalafil (cialis)
Vardenafil
Avanafil
How do you take PDE5 inhibitors
30-60 min prior to sex
Avoid with food (except tadalafil)
Physical stimulation is still needed! PDE-I allow erection to be sustained, they do NOT initiate erection
What is significant about Tadalafil
Approved for low dose daily dosing for BPH and ED!
Has a longer half life, stays in system 36 hrs when used prn
Back pain is associated with tadalafil (isoenzyme 11 inhibitor)
What is Yohimbine
a natural ED Tx, not significantly better than placebo
What is a VED
Cylinder placed over penis to create vacuum
Causes increased arterial blood flow
When removed, place constriction ring at base of penis to maintain erection
**REMOVE ring before falling asleep!
What is MUSE
Alprostadil (PGE1) in form of Urethral suppository (pellet)
Increases cAMP= decreased IC calcium= cavernosal artery vasodilation
Take 5-20 min before sex
**first dose should be taken under medical supervision to monitor for hypotension
What is an intracavernosal injection
Alprostadil (PGE), brand name Caverject or Edex, is injected into ONE side of the cavernosa causing vasodilation
Do not exceed 3 doses x week. Take first dose under supervision, titrate at home
After injection, apply pressure to prevent fibrosis
Erection should occur in 10-15 min, and last no longer than ONE HOUR
What are risks of penile injection
Pain infection bleeding fibrosis and curvature priapism
What is a priapism
erection maintained beyond 4 hours
causes pain, stasis, hypoxia (CHECK ABGs), acidosis, fibrosis, and ED
this is a urologic EMERGENCY
How do you treat a priapism
18-19 gauge needle in cavernosum, aspirate blood
Infuse saline
Inject phenylephrine (vasoconstrictor)
May need surgery for shunt!
We want to prevent fibrosis, loss of cavernosal tissue, and recurrent priapisms
What is a constriction ring
Tx for venous leakage! adjustable and should be easily removed
What is a penile splint
ring placed at base of glans (corona), rigid bar runs along spongiosum, and another ring at base of penis
Sized to patient, tumescence is NOT required
What is penile prosthesis
surgical implant of rods into penile shaft
Non-inflatable are goose neck rods that are malleable and bent into and out of position
Inflatable is two rods placed in peniv, with reservoir posterior to abdominal wall, and pump in scrotum
What are complications of inflatable penile prosthesis
erosion
infection
autoinflation
mechanical failure
What is penile revascularization
Tx for focal arterial occlusion of cavernosal artery
Anastomose inferior epigastric artery to dorsal penile artery
What does ED allow the opportunity for as a provider
discussion of CVD and motivation for lifestyle changes
