Aspirin Overdose Flashcards
Define Aspirin Overdose ?
Excessive Injestion of Aspirin causing toxicity
What is the aetiology of aspirin overdose?
It can be a result of deliberate self-harm, suicidal intent or by accident
10-20 g can cause moderate-severe toxicity by adults
What is the pathophysiology of Aspirin Overdose?
Increases respiratory rate and depth by stimulating the respiratory centre
This hyperventilation leads to respiratory alkalosis(in the early stage)
The body compensates by increasing urinary bicarbonate and K+ excretion
This leads to dehydration and hypokalaemia
Loss of bicarbonate, uncoupling of mitochondrial oxidative phosphorylation and the build up of lactic acid can lead to metabolic acidosis
In severe cases, CNS depression and respiratory failure can occur
What is the epidemiology of aspirin overdose?
One of the MOST COMMON drug overdoses
What are the key questions to remember when taking a history for aspirin overdose?
How much aspirin was taken?
When was it taken?
Were any other drugs taken?
Have you had any alcohol?
What’s important to remember with aspirin overdose?
The patient may initially be asymptomatic
What are the early symptoms of aspirin overdose?
Flushing Fever Sweating Hyperventilation Dizziness Tinnitus Deafness
What are the later symptoms of aspirin overdose?
Lethargy Confusion Convulsions Drowsiness Respiratory Depression Coma
What are the signs of Aspirin Overdose on physical examination?
Fever
Tachycardia
Hyperventilation
Epigastric Tenderness
What bloods would you do for aspirin overdose?
Salicylate levels FBC U&Es - check for hypokalaemia LFTs - high AST/ALT Clotting Screen - high PT Other drug levels (e.g. paracetamol) ABG - may show mixed metabolic acidosis and respiratory alkalosis
What would you expect on an ECG for aspirin overdose?
Signs of hypokalaemia- flattened/inverted T waves, U waves, prolong PR interval, ST depression
