- Pdet = Pves − Pabd (Det Ves Abd → "Bladder is a DIVA").
- Storage pressure >40 cm H₂O is associated with harmful effects on the upper tract.
- ALPP <60 cm H₂O suggests ISD; >90 cm H₂O signifies little to no ISD.
- Normal compliance: 46–124 mL/cm H₂O; rapid filling can give false-positive low compliance.
- BOOI ≥40 obstructed, ≤20 unobstructed; BCI >150 strong, <100 weak.
- DESD only exists with neurologic lesion between infrapontine and suprasacral cord — view with skepticism otherwise.
- Primary bladder neck obstruction can only be diagnosed on VUDS.
- DIAPPERS mnemonic for causes of transient incontinence.
- Strongest RF for UI in men is age; in women, vaginal delivery, parity, obesity, and pregnancy.
- Oral estrogen ± progestogens worsens UI; vaginal estrogen does not and treats atrophy.
- Anti-cholinergics act mainly in the storage phase via afferent inhibition — safe in BOO but use caution with high PVR.
- M3 is the most important muscarinic receptor for detrusor contraction; M2 predominates ≥3:1 in number.
- Mirabegron contraindicated if SBP ≥180 or DBP ≥110.
- OnabotulinumtoxinA dose: 200U for neurogenic OAB; 100U typical off-label for idiopathic OAB; CIC risk ~5–6%.
- Tamsulosin has the highest risk of intraoperative floppy iris syndrome (40× alfuzosin); hold 4–7 days preop but doesn't eliminate risk.
- Silodosin → most ejaculatory dysfunction; alfuzosin/doxazosin/terazosin minimal.
- Finasteride blocks type II 5-AR; dutasteride blocks types I and II — halve PSA effect; double measured PSA after 1 year of therapy.
- MTOPS: combination > monotherapy for progression and symptom benefit at 4 years.
- CombAT: combination vs. dutasteride alone — no benefit for AUR/BPH-related surgery; combination superior for BPH clinical progression and symptom benefit at 4 years.
- 5-ARI benefits (4): ↓ prostatitis, improve PSA/DRE sensitivity for PCa detection, ↓ AUR, ↓ BPH-related surgery.
- 5-ARI side effects (4): ↓ ejaculate volume, ED, ↓ libido, gynecomastia.
- Desmopressin in females: 25 μg MELT; males 50–100 μg MELT — check sodium baseline, day 7, day 30, then q6 months.
- Hyponatremia risk on desmopressin: <1% age <65, 8% age >65.
- Nocturnal polyuria: >20–33% of 24h volume (age-dependent), >6.4 mL/kg, or >54 mL/hr.
- Bladder ice-water test: healthy bladder retains; bladder with C-fiber–mediated spinal reflex (SCI, MS) cannot retain.
- Spinal shock typically 6–12 weeks in complete suprasacral SCI; sacral SCI → persistent detrusor areflexia.
- Autonomic dysreflexia only in SCI lesions above T6–T8 — sublingual nifedipine 10–20 mg can alleviate or prevent during cystoscopy.
- Suprapubic catheter preferred over urethral in SCI for indwelling drainage (less urethral erosion/epididymo-orchitis); no difference in UTI/stones/incontinence.
- Bladder cancer strongly associated with long-term indwelling catheterization in SCI (SCC).
- MS: most common UDS finding is detrusor overactivity; DSD in 30–65%; sphincter usually synergic in CVA, Parkinson, dementia, brain tumor.
- MSA: open bladder neck (different from PD), striated sphincter denervation on EMG; avoid outlet-reducing procedures in males.
- Fowler syndrome: urinary retention in young women, bladder capacity >1L without urgency, impaired sphincter relaxation on EMG; treat with neuromodulation.
- SNS sacral nerve responses: S2 plantarflexion of entire foot + leg/thigh paresthesias; S3 plantar flexion of great toe + bellows reflex + rectum/scrotum/vagina paresthesias; S4 bellows only + rectum only.
- PTNS = third-line OAB therapy per 2019 AUA OAB — moderately severe symptoms, willing to comply with protocol.
- AUA BPH 2021 surgical indications: refractory urinary retention, recurrent UTI, recurrent bladder stones, recalcitrant gross hematuria, renal insufficiency (GFR <60 for ≥3 months), progressive bladder dysfunction, refractory or intolerant to medical therapy.
- Prostate size–based BPH surgery: <30 g → TUIP, TURP, PVP, TUVP, TUMT, laser enucleation; 30–80 g → TURP/PVP/TUVP/TUMT/laser enucleation/WVTT/RWT/PUL; >80 g → simple prostatectomy or laser enucleation.
- Sexual-function-preserving BPH surgery: PUL and WVTT.