Aspirin overdose

Question 1

Aspirin is the most common cause of ___ poisoning

Answer 1

Salicyclate

Question 2

What are the main clinical features of aspirin overdose?

Answer 2

Symptoms:

Nausea and vomitting

Epigastric pain

Tinnitus

Lethargy

Confusion

Dizziness

Signs:

Fever

Hyperventilation

Diaphoresis

Tachycardia with bounding pulse

Pulmonary oedema

Seizures

Coma

Question 3

What signs on clinical examination are suggestive of aspirin overdose?

Answer 3

Fast RR (Hyperventilation)

Diaphoresis

Tacchycardia with bounding pulse

Signs of pulmonary oedema
* Reduced breath sounds
* Coarse crackles
* Pink frothy sputum

Fevers

Question 4

What investigations should be conducted in patients suspected of aspirin overdose?

Answer 4

Bedside:

Basic obs

ECG: Check for QRS widening, AV block or ventricular arrhythmias

Urinary pH

Bloods:

Salicyclate levels

Venous blood gas: Check for respiratory alkalosis/metabolic acidosis

U&Es: Check for hypokalaemia and AKI

Magensium: Need to also correct before correcting hypokalaemia

Paracetamol levels: (Check for mixed overdose)

Question 5

What findings from VBG occur during aspirin overodse? (2)

Answer 5

Respiratory alklaosis due to hyperventialtion (Early presentation)

Metabolic acidosis (Late presentation)

Question 6

Respiratory alkalosis occurs as an early or late presentation of aspirin overodse?

Metabolic acidosis occurs as an early or late presentation of aspirin overodse?

Answer 6

Respiratory alkalosis (early)

Metabolic acidosis (late)

Question 7

Aspirin overdose can result in what ECG changes? (3)

Answer 7

QRS prolongation

AV node block

Ventricular arrythmias

Due to metabolic acidosis

Question 8

What ECG changes can occur due to hypokalaemia?

Answer 8

PR prolongation

Widespread ST depression

T wave flattening

Prominent U waves

Question 9

What findings from U&Es can occur during aspirin overdose?

Answer 9

Hypokalaemia

AKI (raised serum creatinine, urea0

Question 10

How are patients with suspected aspirin overdose managed?

Answer 10

1) IV fluid resuscitation (if volume deplete)

2) Electrolyte correction (correct hypokalaemia)

3) IV sodium bicarbonate to promote salicyclate excretion (ONLY after hypokalaemia managed)

4) Manage complications
* Hyperthermia: cooling measures
* Seizures: Benzodiazepines

5) Consider charcoal if ingested less than 1 hour ago

Question 11

When is charcoal given for patients with aspirin overdose?

Answer 11

If aspirin was ingested less than 1 hour ago

Question 12

What must always be corrected for before correcting hypokalaemia?

Answer 12

Magnesium

Magnesium deficiency impairs potassium reabsorption in the renal tubules, exacerbating potassium losses. Hypomagnesaemia can hinder the effectiveness of potassium replacement.

Question 13

When is haemodialysis considered for patients with aspirin overodse?

Answer 13

Either of following:

• Salicyclate levels >700mg/kg
• Severe metabolic acidosis
• Seizure/coma

Question 14

Once patient is stabilised for overdose, what further assessment is required?

Answer 14

Psychiatric evaluation