Overdose of ASA, due to consumption of >10 g of ASA in adults and 3 g in children.
Clinical features
- Mild to moderate toxicity (after 1-2 hours): hyperventilation, tinnitus, deafness, nausea, vomiting, dizziness, vasodilation
- Severe toxicity: hyperpyrexia, convulsions, altered mental status, non cardiac pulmonary oedema, coma
- Complex acid-base disturbances (acidosis)
Management
Stabilise vital signs
- Oxygen and IV fluids as necessary
- Gastric lavage: worthwhile up to 4 hours after poisoning as stomach emptying is delayed
- Activated charcoal 50 g repeated as needed every 4 hours or 25 g repeated prn every 2 hours
- It delays absorption of any remaining salicylate
- Treat/prevent hypoglycaemia with Dextrose 50% 50-100 ml (Dextrose 10% 2-5 ml/kg in children)
- Tepid sponging for hyperpyrexia
- Treat convulsions with IV diazepam 10 mg prn
Refer to higher level of care if coma, pulmonary oedema, renal insufficiency, clinical deterioration in spite of above measures
- Treat acidosis and enhance renal excretion in symptomatic patients with Sodium bicarbonate
- Bolus 1-2 mEq/kg (max 100 mEq) in 3-5 minutes
- Followed by an infusion of 50-75 mEq in 500 ml of Dextrose 5 %; run at 250 ml/hour in adults (run at 1.5-2 times maintenance in children)
- Mantain urine pH 7.5-8