Ethylene glycol poisoning

T52.8 + (X46.99/X66.99/Y16.99)

DESCRIPTION

Ethylene glycol is the main component of motor vehicle radiator coolant/antifreeze and is occasionally found in brake fluid. It is also found in homemade toilet and drain cleaners.

Mild to moderate intoxication: Resembles alcohol intoxication, with nausea and vomiting, nystagmus, ataxia and somnolence.

Severe intoxication:

Associated with more severe CNS depression (coma, hypotonia, hyporeflexia) and high anion gap metabolic acidosis. Cardiovascular signs include tachycardia and hypertension. Calcium oxalate crystals cause renal failure and hypocalcaemia, which may manifest with prolongation of the QT interval or tetany.

Anion gap calculation = Na – (CI + HCO3) (Normal = 8-16).

GENERAL MEASURES

Immediate consultation with the Poisons Information Helpline is important.

Early treatment with antidote may prevent formation of toxic metabolites.

Monitor blood gases and administer sodium bicarbonate

Early haemodialysis is the treatment of choice for severe poisoning with profound acidosis.

MEDICINE TREATMENT

Ethanol

Indications:

History of ingestion, plus any two of the following criteria:

  • Arterial pH <7.3
  • Serum bicarbonate <20 mmol/L
  • Presence of urinary oxalate crystals (ethylene glycol only) or visual disturbances (methanol only)

LoEIII [54]

Dose:

  • Ethanol 95% BP, oral,
    • Loading dose 1 mL/kg
    • Maintenance dose:
      • non-drinker: 0.125 mL/kg/hr
      • chronic drinker: 0.2 mL/kg/hr
    • Dilute the calculated ethanol volume to 20% (1:5) in any suitable liquid.

OR

  • Ethanol 40% (gin, whiskey, vodka), oral
    • Loading dose: 2 mL/kg
    • Maintenance dose:
      • non-drinker: 25 mL/kg/hour
      • chronic drinker: 0.5 mL/kg/hour
    • Dilute the calculated ethanol volume to 20% (1:2) in any suitable liquid.

LoEIII [55]

Note:

  • If patients are not co-operative, administer ethanol via a nasogastric tube.
  • Maintain ethanol levels of 1–1.3 g/L (100–130 mg/dL).
  • The dose of ethanol needs to be increased if the patient is receiving concomitant haemodialysis.
  • Several days of ethanol therapy may be required until clinical condition improves.

LoEIII [56]

Cofactor therapy:

  • Thiamine, oral, 100 mg daily.
  • Pyridoxine, oral, 100 mg daily.

LoEIII

Metabolic acidosis E87.2 + (T52.8/X46.99/X66.99/Y16.99)

  • Sodium bicarbonate, IV, 50–100 mmol/L administered over 30–45 minutes.

Note:

  • Rapid correction of acidosis may precipitate seizures in a hypocalcaemic patient. Correct severe or clinically evident hypocalcaemia.
  • Monitor glucose levels and correct hypoglycaemia, if necessary.

LoEIII [57]

REFERRAL

Severe poisoning with profound acidosis for early haemodialysis.