Aspirin Overdose

Question 1

Define:

Answer 1

Excessive ingestion of aspirin leading to toxicity

Question 2

Aetiology/risk factors:

Answer 2

May be self harm, suicidal intent or an accident
• 10-20 g can cause moderate-severe toxicity in adults

Increases the resp rate and depth leading to hyperventilation. This leads to resp alkalosis so body increases excretion of bicarb and k+ = dehydration + hypokalemia

Question 3

Epidemiology:

Answer 3

Most common drug overdose

Question 4

Questions to ask:

Answer 4

How much?
Other drugs?
Alcohol?

Question 5

Early symptoms:

Answer 5

o	Flushed 
o	Fever
o	Sweating 
o	Hyperventilation 
o	Dizziness 
o	Tinnitus 
o	Deafness 
o	Vomiting 
May initially be asymp

Question 6

Later symptoms:

Answer 6

o	Lethargy
o	Confusion
o	Convulsions
o	Drowsiness 
o	Respiratory depression 
o	Coma

Question 7

Signs:

Answer 7

Tachycardia
Hyperventilation
Fever
Epigastric tenderness

Rare - reduced CNS, hypotension, heart block, seizures, hyperthermia and pulmonary oedema

Question 8

Investigations:

Answer 8

Salicyclate levels
FBC 
U+Es - looking for hypokalaemia 
LFTS - AST and ALT increased
Clotting - PT increased 
Other drug levels 
ABG - mixed metabolic acidosis with resp alkalosis 

ECG - hypokalaemia (inverted or flattened T waves), u waves, st depression, prolonged PR

Question 9

Treatment:

Answer 9

Sodium bicarbonate