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GU — TURP Syndrome and Robotic Prostate
TEXTSpecialty II · 9 min read
Hyponatremia from glycine absorption + steep Trendelenburg robotic physiology + ureteral colic. GU has three unique anesthetic stories.
After this lesson you can
4 min read8 sections- Recognize TURP syndrome.
- Plan robotic prostatectomy positioning.
- Manage hypotension under steep Trendelenburg.
- Anticipate venous air embolism risks.
TURP syndrome — pathophysiology
The classic irrigant glycine 1.5% is hypotonic + free of electrolytes dilutional hyponatremia + intravascular volume overload.
Volume absorbed depends on resection time (1 mL/min average, ranges to 20 mL/min), prostate size, irrigation bag height (higher = more pressure = more absorption), and venous sinus exposure.
Modern bipolar TURP uses normal saline irrigation eliminates the hyponatremia + free-water absorption issue but volume overload still possible.
Glycine metabolism ammonia + glyoxylate contributes to altered mental status and TRANSIENT VISUAL CHANGES (glycine is a retinal inhibitory neurotransmitter — patients report blurred vision or transient blindness).
TURP syndrome recognition + severity
- visual disturbance (early in awake spinal patients)
- nausea/vomiting
- restlessness
- headache
- pulmonary edema
- seizure
- coma
CARDIOVASCULAR signs of volume overload: rising CVP, pulmonary edema on auscultation + CXR, JVD.
RECOGNITION advantage of SPINAL anesthesia: awake patient reports visual changes + confusion EARLY, often before serum sodium derangement is detected on labs.
Under GA, TURP syndrome can present only as unexplained hypotension + bradycardia + bleeding diathesis from dilution — much harder to recognize.
TURP syndrome management
20-40 mg IV — promotes free water excretion + relieves volume overload.100 mL bolus IV over 10 min, repeat × 2-3 if no improvement.Goal: raise Na 4-6 mEq/L acutely to break severe symptoms.
10-12 mEq/L per 24 hr to avoid central pontine myelinolysis (osmotic demyelination).
Spinal vs GA for TURP
- awake patient reports symptoms (early TURP syndrome detection via visual changes + confusion + restlessness)
- less PONV
- faster recovery
- no airway manipulation in elderly comorbid population
- possibly reduced bleeding
T10 sensory level sufficient (lower abdomen + perineum + bladder).
GA acceptable but obscures early TURP syndrome diagnosis; only late hemodynamic changes alert.
Studies suggest spinal MAY reduce TURP syndrome incidence (perhaps via lower venous pressure from sympathectomy) and improve outcomes; data not definitive.
Modern bipolar/saline TURP reduces but does not eliminate the risk of volume overload + sodium issues.
Patient + surgeon preference + comorbidity profile guide the choice.
Robotic prostate — steep Trendelenburg physiology
- increased ICP + IOP (head down + pneumoperitoneum-related raised CVP transmits to brain + eye)
- decreased FRC + lung compliance + atelectasis (gravitational shift of abdominal contents + diaphragm cephalad)
- increased peak airway pressure
- hemodynamic preload increase initially then decrease as pneumoperitoneum compresses IVC
- venous congestion of head/neck facial + conjunctival + airway edema
- corneal abrasion
- ION (ischemic optic neuropathy) — extremely rare but devastating
- ETT migration deeper as carina rises (re-check tube position after positioning)
- arm-tucking nerve injuries
- unconsented motion if patient slips on table
- severe glaucoma
- raised ICP
- severe COPD
- severe CHF
Robotic prostate — anesthetic management
- IV access on tucked arm (cannot easily access during case)
- arterial line for monitoring + ABGs
- foley + OG
- bilateral SCDs
- eye protection (lubricant + tape + protective gel pads)
Padding all pressure points + neutral arm position avoiding stretch.
INDUCTION + INTUBATION before steep Trendelenburg.
- lung-protective tidal volume
6-8 mL/kg IBW - PEEP
8-10 cmH₂O - recruitment maneuvers q1h
- watch peak inspiratory pressure (≤35 cmH2O)
- accept mild permissive hypercapnia
- return to supine BEFORE extubation
- allow facial edema to resolve
- leak test if concern
- extubate awake
Post-resection blood loss + ongoing care
Continuous bladder irrigation post-op via 3-way Foley to prevent clot retention + outflow obstruction.
Hgb checks q4-6h × 24 hr.
Coagulopathy from dilution (TURP syndrome) or release of fibrinolytic substances from prostate can worsen bleeding — TXA used off-label.
Transfusion threshold Hgb 7 in healthy patients, 8-9 in cardiac comorbidity.
Watch for bladder spasms (anticholinergic — oxybutynin) and post-obstructive diuresis (large urine output for 24-72 hr requires fluid + electrolyte replacement).
Ureteral colic + stone surgery
Pain typically severe in PACU from ureteral stent or stone passage — opioid + ketorolac (if no contraindication or surgeon agreement) + antispasmodics + alpha-blocker (tamsulosin) for stent-related discomfort.
ESWL (extracorporeal shock wave lithotripsy): outpatient, prone position with water bath or pad, GA or MAC + sedation.
Bladder spasms post-op common with stents — oxybutynin or solifenacin.
PCNL (percutaneous nephrolithotomy): prone position, larger incision, more blood loss potential.
⚠ Common pitfalls
- Late TURP-syndrome recognition — confusion, vision changes, seizure from hyponatremia.
- Forgetting steep Trendelenburg effects — ↑ICP, IOP, FRC ↓.
- Routine bipolar lithotripsy assumed safe from TURP syndrome — it's safer but not zero.
- Aggressive Trendelenburg in glaucoma — vision-threatening IOP rise.
💎 Clinical pearls
- TURP syndrome triad: hyponatremia + hypoosmolality + neurologic changes.
- Hypertonic saline (3%) for severe symptomatic hyponatremia — slow correction to avoid central pontine myelinolysis.
- Bipolar TURP uses isotonic saline — eliminated dilutional hyponatremia risk.
- Robotic prostatectomy: 30-45° Trendelenburg + pneumoperitoneum × hours — pre-anesthetic exam includes glaucoma + cerebral.
Recap
- TURP syndrome triad: hyponatremia + hypoosmolality + neurologic changes.
- Hypertonic saline (3%) for severe symptomatic hyponatremia — slow correction to avoid central pontine myelinolysis.
- Bipolar TURP uses isotonic saline — eliminated dilutional hyponatremia risk.
- Robotic prostatectomy: 30-45° Trendelenburg + pneumoperitoneum × hours — pre-anesthetic exam includes glaucoma + cerebral.
Mark each section done to complete the module.