- Priapism definition: persistent penile erection > 4 hours beyond or unrelated to sexual stimulation; three subtypes — ischemic (low-flow, painful, hypoxic), non-ischemic (high-flow, traumatic, painless), and recurrent ischemic (stuttering)
- Ischemic priapism corporal blood gas: PO2 <30, PCO2 >60, pH <7.25 (vs normal arterial PO2 >90 / PCO2 <40 / pH 7.40)
- Erectile function recovery in SCD priapism: 100% if reversed by 12h, ~75% by 12–24h, ~50% by 24–36h, 0% if ≥36h; intervention beyond 48–72h has little benefit for potency
- Ischemic priapism first-line: intracavernosal phenylephrine + corporal aspiration ± irrigation, started as soon as possible after diagnosis
- Phenylephrine dosing: 100–500 mcg/mL diluted in saline, injected at 3 or 9 o'clock position, doses ≥5 min apart, monitor BP/HR; hypertensive stroke reported with cumulative 2 mg
- Shunting: distal shunts (Winter, Ebbehoj, T-shunt, Al-Ghorab, tunneling) attempted before proximal (Quackles, Grayhack, Barry); shunting not recommended >72 hours
- Early penile prosthesis considered for acute ischemic priapism >36 hours or shunt failure — preserves length, relieves pain, restores function
- Non-ischemic priapism: not an emergency; observation first-line for 4 weeks; second-line percutaneous fistula embolization (bilateral embolization increases ED risk)
- Peyronie's epidemiology: prevalence 9%, peak onset early 50s; post-RP prevalence 11–16%
- Peyronie's natural history: pain resolves in ~90%; curvature improves 12–13%, worsens ~45%, stable ~42%
- Active (acute) Peyronie's: dynamic symptoms, pain hallmark, up to 18 months; stable: ≥3 months unchanged
- Penile fracture deviates AWAY from injury side; Peyronie plaque deviates TOWARD affected side (60–70% dorsal plaques)
- Collagenase (Xiaflex) IMPRESS I/II: 17° vs 9° improvement vs placebo (8° absolute difference); indicated for stable disease, curvature 30–90°, intact erectile function — NOT for hourglass, ventral curvature, calcified plaque, proximal plaque, or curvature <30° or >90°
- Peyronie's surgical indications: stable ≥1 year + ≥3–6 months stable deformity, compromising intercourse, failed non-surgical, desire for definitive result
- Plication (Nesbit, Yachia, 16-dot) for curvature <70°, minimal hourglass/hinge — lower ED risk, causes shortening; grafting (Tutoplast, porcine SIS) for >70°, complex deformity — preserves length but higher ED risk; prosthesis for refractory ED + severe deformity
- ED neuroanatomy: parasympathetic S2–S4 = erection (tumescence); sympathetic T10–L2 = detumescence/emission; pudendal nerve (Onuf S2–S4) = sensation and ischiocavernosus/bulbocavernosus contraction
- Nitric oxide is principal erection neurotransmitter; nNOS initiates, eNOS maintains; cGMP causes smooth muscle relaxation; PDE5 degrades cGMP; norepinephrine mediates flaccidity
- SCI and erection: above T10 — reflex only; L2–S2 — both; below S2 — psychogenic only (weaker); reflex erection preserved in 95% of complete upper cord lesions
- Massachusetts Male Aging Study: ED prevalence ~40% in 40s, increases ~10% per decade; severe ED tripled from 5% (40s) to 15% (70s)
- ED-associated antihypertensives: α2-agonists (clonidine), methyldopa, diuretics (spironolactone, thiazides), non-selective β-blockers; NOT associated: ACE-I, ARBs, calcium channel blockers, α1-blockers (cause retrograde ejaculation), β1-selective blockers
- Bupropion is the antidepressant NOT associated with ED
- AUA ED mandatory workup: history/physical, diabetes screen (FBG or HbA1c), morning total testosterone; CUA: history/physical only mandatory
- IIEF 5 domains: sexual desire, erectile function, intercourse satisfaction, ejaculatory/orgasmic function, overall sexual satisfaction
- Penile duplex US is gold standard for vascular ED: PSV <25–30 cm/s = arterial insufficiency; EDV >5 cm/s or RI <0.80 = veno-occlusive dysfunction
- PDE5i pharmacokinetics: sildenafil/vardenafil 30–60 min onset, ~4h T½, food affects; tadalafil 60–120 min onset, 17.5h T½, food unaffected; avanafil 15–30 min onset, 5h T½, food unaffected
- PDE5i absolute contraindications: nitrates, hypersensitivity; vardenafil specifically contraindicated with type 1A/3 antiarrhythmics and congenital long QT
- NAION risk with PDE5i: 3 additional cases per 100,000 men age ≥50
- Intracavernosal injection contraindications (MAOIs/Coagulopathy/Cardiovascular/Infection/Priapism): MAOI use, reduced manual dexterity, psychological instability, severe coagulopathy or unstable CVD, history of priapism
- Penile prosthesis: 70% of US implants are 3-piece inflatable; infection rate 1–3% primary, 7–18% revision; ~50% functional at 20 years
- Most likely prosthesis infection organisms: S. epidermidis, S. aureus, Candida albicans
- Antibiotic prophylaxis (2019 AUA): aminoglycoside + cephalosporin or vancomycin, 1 hr pre-op to 24h post-op for prosthetic implants
- Salvage prosthesis contraindications: Enterococcus, tissue necrosis, sepsis, DKA, cylinder erosion into urethra
- Ejaculation control: emission = sympathetic T10–L2 (vas, SV, prostate contraction; bladder neck closure); ejection = somatic pudendal S2–S4 (BC/pelvic floor rhythmic contraction); RPLND can damage hypogastric nerves causing failure of emission
- Premature ejaculation (ISSM 2013): lifelong PE = ejaculation within ~1 min of penetration; acquired PE = reduction in latency to ~3 min or less; both require inability to delay + distress
- PE treatment: SSRIs (paroxetine strongest, IELT increases ~8.8×), topical anesthetics (lidocaine/prilocaine 20–30 min pre-intercourse), dapoxetine on-demand, PDE5i if comorbid ED, tramadol, α-blockers
- Delayed ejaculation: latency >25–30 min with distress; SCI ability to ejaculate increases with descending injury level (<5% retain ability with complete upper motor neuron lesions)
- Testosterone deficiency diagnostic criteria: morning total testosterone <300 ng/dL on 2 separate occasions PLUS symptoms/signs
- Primary hypogonadism (high LH/FSH) — DUNKY XX: Down, undescended testis, Noonan's, Klinefelter (47XXY), Y-microdeletions, XX-male; secondary (low/normal LH) — Kallmann (GnRH deficiency), pituitary tumor, hyperprolactinemia, opioids, severe chronic illness
- Initial workup after low T confirmed: serum LH (low → check prolactin to screen for hyperprolactinemia); pituitary MRI if testosterone <150 ng/dL or persistent hyperprolactinemia
- Pre-treatment evaluation: Hct (hold if >50%), estradiol (if breast symptoms), testicular exam + FSH (if fertility desired), PSA (if age >40 or PCa history)
- Testosterone target: 450–600 ng/dL (middle tertile of normal)
- Testosterone contraindications (CHEAPS BLUTS): metastatic prostate cancer, breast cancer, poorly controlled CHF, Hct >50%, elevated PSA, abnormal DRE, unevaluated sleep apnea, severe LUTS (IPSS >19); hold 3–6 months after CV event
- Exogenous testosterone suppresses spermatogenesis — contraindicated if trying to conceive; 2/3 recover sperm by 6 months after cessation, 10% take into second year
- Fertility-preserving alternatives: SERMs (clomiphene, tamoxifen), aromatase inhibitors (anastrozole), hCG (LH agonist); only hCG FDA-approved for hypogonadotropic hypogonadism
- TRAVERSE 2023: no significant difference in primary cardiovascular composite outcomes between testosterone and placebo gel; higher incidence of atrial fibrillation, AKI, and PE in testosterone group
- Monitoring on TRT: total testosterone and Hct every 6–12 months; intervene if Hct ≥54%; consider stopping if no symptom improvement at 3–6 months