Salicylate poisoning

Uncoupling of oxidative phosphorylation leads to anaerobic metabolism and the production of lactate and heat.
Effects are dose related and potentially fatal:

• 150mg/kg: mild toxicity.
• 250mg/kg: moderate

• 500mg/kg: severe toxicity.

• Levels over 700mg/L are potentially fatal.

Investigations

• Paracetamol and salicylate level
• Glucose
• Urea, Creatinine
• Electrolytes
• Liver Function Tests
• INR
• ABG
• CBC
• HCO3
• Urine PH

Management

1. General measures: (See Acute poisoning article—general measures).
2. Correct dehydration.
3. Keep patient on ECG monitor.
4. Give activated charcoal to all presenting ≲1h—consider even if delayed presentation, at least one dose of 1g/kg (max 50g). Consider repeat doses (two further doses of 50g, 4h apart).
5. Do Investigations (see above)
6. Salicylate level may need to be repeated after 2h
7. Monitor blood glucose 1–2hrly (beware hypoglycemia)
8. if severe poisoning, monitor salicylate levels, serum pH, and Urea, Creatinine, & Electrolytes.
9. Catheterization to monitor urine output and pH
10. Correct acidosis: If plasma salicylate level >500mg/L (3.6mmol/L) or severe metabolic acidosis, consider alkalinization of the urine, e.g. with 1.5L 1.26% sodium bicarbonate IV over 3h. Aim for urine pH 7.5–8.
11. Monitor serum K+ as hypokalemia may occur, and should be treated (caution if AKI).
12. Dialysis may well be needed if salicylate level >700mg/L, and if AKI or heart failure, pulmonary or cerebral oedema, confusion or seizures, severe acidosis despite best medical therapy, or persistently ↑plasma salicylate. Contact nephrology early.