Makindo Medical Notes

Related Subjects: | Sodium Physiology | Hyponatraemia | TURP Hyponatraemia Syndrome | Hypernatraemia | Diabetes Insipidus | Benign Prostatic Hyperplasia | Prostate Cancer

Transurethral Resection (TUR) Syndrome is an iatrogenic form of water intoxication characterized by a combination of fluid overload and hyponatraemia due to the absorption of large volumes of hypotonic irrigation fluids (e.g., glycine, sorbitol, mannitol) used during TURP to maintain a clear surgical field. A sudden drop in serum sodium levels leads to progressive cerebral oedema, resulting in cellular swelling and dysfunction.

TURP Hyponatraemia Syndrome (Aim to raise Na+ by no more than 8–12 mmol/L in 24 hours)

Fluid overload can lead to sudden hyponatraemia and pulmonary oedema. Rapid correction of hyponatraemia can cause central pontine myelinolysis; sodium levels should be corrected slowly. Immediately stop irrigation and restrict further fluid intake to prevent worsening fluid overload. Perform ABC assessment and resuscitate if the patient is comatose or experiencing seizures. Significant symptoms usually occur when Na+ is < 110 mmol/L. Administer intravenous Furosemide 40–80 mg stat to promote diuresis and reduce fluid overload. Consider 3% hypertonic saline if Na+ is < 120 mmol/L. Administer 50–100 ml of 3% NaCl over 2–3 hours under careful monitoring. Seek urgent senior help and consider ICU admission. Check sodium levels every few hours. For persisting or recurring seizures, administer intravenous Lorazepam 2–4 mg.

About

• A cause of acute hyponatraemia following Transurethral Resection of the Prostate (TURP).
• A medical emergency in surgical patients due to rapid-onset hyponatraemia.
• Results from absorption of irrigation fluid volumes of 2000 ml or more.

Aetiology

• TURP Procedure: Involves removal of prostatic tissue using electrocautery.
• Irrigation Solution: Used to distend the bladder, clear the surgical site, and remove blood and resected tissue.
• Fluid Absorption: Hypotonic fluids like glycine (osmolarity of 200 mOsm/L) are absorbed into the systemic circulation, leading to dilutional hyponatraemia.
• Use of Glycine: Normal saline cannot be used as it conducts electricity, posing a risk during electrocautery. Distilled water is non-conductive but can cause severe hyponatraemia, intravascular haemolysis, and hyperkalaemia.
• Renal Complications: Haemoglobin precipitation in renal tubules can lead to acute renal failure.

Prevention

• Use isotonic or near-isotonic irrigation fluids when possible.
• Limit the duration of the TURP procedure to reduce the risk of significant fluid absorption.
• Monitor fluid balance and electrolyte levels closely during and after the procedure.
• Ensure surgical and anaesthesia teams are trained to recognize and manage early signs of TUR syndrome.
• Consider using bipolar electrosurgical systems that allow the use of saline irrigation.

Clinical Features

• Transient prickling and burning sensations in the face and neck, along with lethargy and apprehension.
• Restlessness and headache.
• Confusion, seizures, coma.
• Bradycardia and arterial hypotension.
• Symptoms may occur during surgery or in the immediate postoperative period.
• Progression to severe neurological symptoms if not promptly addressed.

Investigations

• Serum Electrolytes: Low sodium levels (e.g., Na⁺ < 120 mmol/L).
• Plasma Osmolality: Reduced osmolality due to dilutional hyponatraemia.
• ECG Monitoring: May show arrhythmias due to electrolyte imbalances.
• Fluid Balance Records: Assess for signs of fluid overload.

Management

• Immediate Actions:
  • Perform ABC assessment and provide oxygen.
  • Stop irrigation fluids and the surgical procedure if intraoperative.
  • Restrict further fluid intake.
• Correction of Hyponatraemia:
  • Correct sodium levels slowly to prevent central pontine myelinolysis.
  • Use hypertonic saline cautiously; aim to raise Na⁺ by no more than 8–12 mmol/L in 24 hours.
• Diuretics: Administer intravenous Furosemide to promote diuresis.
• Seizure Control: Use intravenous benzodiazepines (e.g., Lorazepam) for seizures.
• Monitoring: Frequent checks of sodium levels, vital signs, and neurological status.
• Intensive Care: Admit to ICU for close monitoring and management.
• Consult Specialists: Involve nephrology and critical care teams as needed.

Review

• Transurethral Resection of the Prostate Syndrome: Almost Gone but Not Forgotten