TURP Syndrome

Syndrome of cardiac and neurological toxicity occurring due to systemic absorption of glycine which causes:

Epidemiology and Risk Factors

Prevalence:

  • Confusion, nausea, vomiting in ~2% of TURP patients

Primary risk factor is rate and amount of irrigation fluid absorption:

  • Volume absorbed is directly proportional to degree of hyponatraemia
    ~10mmol/L fall for each 1L of irrigation fluid absorbed; though this will vary depending on lean body weight.
  • Factors influencing rate of absorption:
    • Operating time
      ⩾1 hour.
    • Low venous pressure
      CVP ⩽10 will permit fluid absorption.
      • Hypovolaemia
      • Hypotension
    • Extensive bleeding
    • Capsular perforation
    • High irrigation fluid pressure

Pathophysiology

Occurs due to systemic absorption of hypertonic, non-conductive irrigation fluid in percutaneous procedures using unipolar diathermy:

  • Use is rarer now that bipolar diathermy more common
    Though large fluid shifts still occur due to absorption of irrigation fluid.
  • Procedures include
    • TURP
    • Hysteroscopy

Fluids used include:

  • Glycine 1.5%
    220mOsmol/kg.
  • Sorbitol 3%
  • Mannitol 5%

Effects due to:

  • Osmolality
    Effects mostly due to hypoosmolality, rather than hyponatraemia.
  • Circulating volume
  • Direct neurological effects of glycine
    Acts as major inhibitory neurotransmitter and potentiates NMDA in CNS.
    • Less common with sorbitol
    • Significantly less common with mannitol

Clinical Features

Timing:

  • Intraoperatively
    Within 15 minutes.
  • Post-operatively
    Up to 24 hours.

Presentation:

  • Early:
    • Headache
    • Restlessnes
    • Dyspnoea
    • Burning sensation in face and hands
    • Visual disturbance
      Mainly due to glycine.
  • Late/severe:
    • Hypoxia
    • Pulmonary oedema
    • Nausea/vomiting
    • Confusion/convulsions/coma

Diagnostic Approach and DDx

Investigations

Management

  • Prevention is key
  • Abandon operation if toxicity occurs
  • Correct hyponatraemia

Prevention:

  • Avoid use of non-electrolyte fluids
    Use bipolar diathermy.
  • Minimise fluid absorption
  • Monitor fluid absorption
    Calculate deficit between administered and suctioned fluid.
  • Have a (predetermined) threshold at which to abandon surgery
    • At 750ml-1L:
      Depending on weight and sex.
      • Cease fluid administration
      • Assess mental state
      • Check serum sodium
    • At 1-2L:
      Depending on weight and sex.
      • Abandon surgery
      • Assess mental state
      • Check serum sodium

Specific therapy:

  • Pharmacological
    • Volume changes
      • Cease IV fluid
      • Frusemide
        Only recommended if APO is present, as it will worsen hyponatraemia.
    • Solute changes
      • 3% NaCl
        • 100ml, Q10 minutely, until resolution or 300ml given
          Each bolus should raise serum sodium by ~2-3mmol/L.
        • Indicated if:
          • Serum sodium is ⩽120mmol/L
          • Serum osmolality is <260mOsm/kg
          • Severe neurological symptoms
            • Transient blindness
            • Persistent nausea/vomiting
            • Severe headaches
            • Severe hypotension
  • Procedural
    • Abandon surgery

Supportive care:

  • C
    • Bradycardia
      • Atropine
      • Adrenaline
  • D
    • Seizures
      • Benzodiazepines
      • Magnesium
        May be considered if refractory.

Anaesthetic Considerations

  • C
    • Arterial line
      Recommended if managing as TURP syndrome.
    • Consider CVC

Complications

  • SIADH occurs in most patients, and impairs correction of hyponatraemia

Prognosis

Associated with significant harm:

  • Morbidity ~20%
  • Mortality ~1%

References

  1. O’Donnell, Aidan M., and Irwin T.H. Foo. ‘Anaesthesia for Transurethral Resection of the Prostate’. Continuing Education in Anaesthesia Critical Care & Pain 9, no. 3 (June 2009): 92–96. https://doi.org/10.1093/bjaceaccp/mkp012.
  2. Hahn RG. Fluid absorption in endoscopic surgery. British Journal of Anaesthesia. 2006 Jan 1;96(1):8–20.
  3. Istre O, Bjoennes J, Naess R, Hornbaek K, Forman A. Postoperative cerebral oedema after transcervical endometrial resection and uterine irrigation with 1.5% glycine. Lancet. 1994 Oct 29;344(8931):1187–9.
  4. American College of Obstetricians and Gynecologists. ACOG technology assessment in obstetrics and gynecology, number 4, August 2005: hysteroscopy. Obstet Gynecol. 2005 Aug;106(2):439-42.