TURP syndrome

Reviewed and revised 16 May 2016

OVERVIEW

• Transurethral resection of the prostate (TURP) syndrome is fluid overload and iso-osmolar hyponatraemia during TURP from large volumes of irrigation fluid being absorbed through venous sinuses
• Irrigation fluid is required to maintain visibility despite bleeding tissue beds
• TUPR syndrome can also occur in other procedures requiring large volumes of irrigation, such as hysteroscopy
• True TURP syndrome is now rare, particularly as glycine-based irrigation fluids are less commonly used

THE IDEAL IRRIGATION FLUID

No such thing exists (of course), but it would have these features:

• transparent (for good visibility)
• electrically non-conductive (to prevent dispersion of the diathermy current)
• isotonic
• non-toxic
• non-haemolytic when absorbed
• easy to sterilize
• inexpensive

PATHOPHYSIOLOGY

Glycine 1.5% in H2O is used as the irrigation fluid

• hyposomolar at 220mmol/L
• non-conductive, non-haemolytic and has a neutral visual density

Patients usually absorb around 20mL/min, average absorption during a case is ~ 1.5L and depends on:

• pressure of infusion (keep bag at <60cm height)
• venous pressure
• exposed vascular bed
• duration of irrigation

Mechanism of clinical manifestations

• symptoms primarily arise from the effects of glycine, which acts as an inhibitory CNS neurotransmitter at GABA receptors and paradoxically potentiates NMDA receptors
•  Increased plasma ammonia may also contribute
• not (usually) from increased brain water!
• glycine also has cardiodepressant effects and may have renal toxicity

Other irrigation fluids

• In the past, other irrigation fluids (e.g. mannitol, sorbitol and glucose) have been used that lack the specific toxic effects of glycine
• More recently, the increased use of bipolar resectoscopes has enabled the use of electrolyte-containing crystalloid solutions that lack glycine toxicity but may contribute to hyponatraemia.

CLINICAL FEATURES

Timing

• it may occur within 15 minutes or be delayed for up to 24 hours post-operatively
• typically lasts hours, but neurological manifestations may be prolonged if complications arise

Early features

• mild cases may go unrecognised
• restlessness, headache, and tachypnoea, or a burning sensation in the face and hands

Features of greater severity

• respiratory distress, hypoxia, pulmonary oedema
• nausea, vomiting
• visual disturbance (e.g. blindness, fixed pupils)
• confusion, convulsions, and coma
• haemolysis
• acute renal failure
• reflex bradycardia from fluid absorption

Symptoms may be masked by general anaesthesia and severe cases may present with dysrhythmias and cardiovascular collapse

RISK FACTORS

• surgical time > 1 hr
• height of bag > 70cm
• resected > 60g
• large blood loss
• perforation of the bladder (leads to rapid absorption from the peritoneal cavity)
• large amount of fluid used
• poorly controlled CHF

INVESTIGATIONS

Laboratory

• hyponatraemia (dilutional effect of a large volume of absorbed irrigation fluid, but later due to natriuresis)
• iso-osmolar (or mildly hypo-osmolar)
• increased osmolar gap from absorbed glycine
• hyperglycinaemia (up to 20 mM; normal is 0.15-0.3mmol/L)
• hyperserinaemia (major metabolite of glycine)
• hyperammonaemia (due to deamination of glycine and serine)
• hyperoxaluria and hypocalcaemia (glycine is metabolised to glycoxylic acid and oxalic acid, the latter forms calclium oxalate crystals in the urinary tracts and may contribute to renal failure)
• metabolic acidosis
• haemodilution and haemolysis

MANAGEMENT

Resuscitation

• Attend to ABCs and address life threats:
  • O2 +/- intubation (or airway protection) and ventilation
  • invasive monitoring

Specific Treatment

• fluid overload: frusemide 40mg IV
• seizures: benzodiazepines +/- other anti-epileptics; consider magnesium (stabilises NMDA receptors)
• hyponatraemia:
  • hypertonic saline is only indicated for neurological manifestations if measured serum osmolality is < 260 mOsmol/kg
  • aim to raise Na+ by no more than 10-12 mmol/24 hours)
  • a rapid increase in plasma sodium is not concerning (this often happens with glycine metabolism), unless there is a sudden change in osmolality (measured osmolality usually changes little as the hyponatremia resolves)
• severe cases may require renal replacement therapy
• treat acute pulmonary oedema and dysrhythmias as required
• treat hypocalcaemia

Treat underlying cause

• stop surgery as soon as possible
• coagulate bleeding points
• stop IV fluid
• monitor Hb

Disposition

• admission to HDU/ ICU (features may worsen due to ongoing absorption of irrigation fluid)

OTHER INFORMATION

• In some centres, ethanol 1% was added to the irrigation solution and the patient’s breath  tested for ethanol every few minutes: a positive test indicates a significant quantity of fluid has been absorbed.

References and Links

Journal articles

• Beal JL, Freysz M, Berthelon G, D’Athis P, Briet S, Wilkening M. Consequences of fluid absorption during transurethral resection of the prostate using distilled water or glycine 1.5 per cent. Canadian journal of anaesthesia. 36(3 Pt 1):278-82. 1989. [pubmed]
• Gravenstein D. Transurethral resection of the prostate (TURP) syndrome: a review of the pathophysiology and management. Anesth Analg. 1997 Feb;84(2):438-46. PMID: 9024044.
• Hamilton Stewart PA, Barlow IM. Metabolic effects of prostatectomy. Journal of the Royal Society of Medicine. 82(12):725-8. 1989. [pubmed]
• Hahn RG. Serum amino acid patterns and toxicity symptoms following the absorption of irrigant containing glycine in transurethral prostatic surgery. Acta anaesthesiologica Scandinavica. 32(6):493-501. 1988. [pubmed]
• O’Donnell AM, Foo IT. Anaesthesia for transurethral resection of the prostate. Contin Educ Anaesth Crit Care Pain. 9(3):92-96. 2009. [article]
• Rhymer JC, Bell TJ, Perry KC, Ward JP. Hyponatraemia following transurethral resection of the prostate. British journal of urology. 57(4):450-2. 1985. [pubmed]
• Trépanier CA, Lessard MR, Brochu J, Turcotte G. Another feature of TURP syndrome: hyperglycaemia and lactic acidosis caused by massive absorption of sorbitol. Br J Anaesth. 2001 Aug;87(2):316-9. PMID: 11493513.