Respiratory Medicine - Salicylate Overdose

Question 1

What does salicylate overdose lead to?

Answer 1

1. Salicylate overdose leads to a mixed respiratory alkalosis and metabolic acidosis.
2. Early stimulation of the respiratory centre leads to a respiratory alkalosis
3. Whilst later the direct acid effects of salicylates (combined with acute renal failure) may lead to an acidosis.
4. In children metabolic acidosis tends to predominate

Question 2

What are the signs of Salicylate overdose?

Answer 2

1. Hyperventilation (centrally stimulates respiration)
2. Tinnitus
3. Lethargy
4. sweating, pyrexia*
5. Nausea/vomiting
6. Hyperglycaemia and hypoglycaemia
7. Seizures
8. Coma

Question 3

What is the treatment for Salicylate overdose?

Answer 3

1. General (ABC, charcoal)
2. Urinary alkalinization with intravenous sodium bicarbonate - enhances elimination of aspirin in the urine
3. Haemodialysis

Question 4

What are the Indications for haemodialysis in salicylate overdose?

Answer 4

1. Serum concentration > 700mg/L
2. Metabolic acidosis resistant to treatment
3. Acute renal failure
4. Pulmonary oedema
5. Seizures
6. Coma