Wed3November0919PM 9

A 30-year-old man is admitted three hours after taking an overdose of amitriptyline and diazepam.

On examination he was drowsy with a Glasgow coma scale of 8; he had a pulse of 140 beats per minute, a blood pressure of 114/88 mmHg, and dilated pupils. His oxygen saturation was 90% on room air.

Which is the most appropriate initial action for this patient?

(Please select 1 option)

Activated charcoal

CT head scan

IV flumazenil

IV atenolol

ECG Correct

Explanation

Obviously this patient with a markedly reduced GCS needs basic resuscitation. However, the most appropriate initial action specifically for his overdose would be to get the investigations (arterial blood gases and ECG) done as quickly as possible, as the latter may show QRS widening and merit treatment.

Gastric decontamination with lavage and activated charcoal is used if the patient presents within one hour of overdose.

Treatment with bicarbonate is also advocated as this patient displays features of severe TCA overdose. The aim is to get the pH >7.4.

He does not need a CT scan as the symptoms are typical of tricyclic overdose.

Flumazenil is not appropriate for this patient as the symptoms are mostly of TCA overdose nor is IV atenolol appropriate for the arrhythmias. A number of studies have shown that in cases of mixed benzodiazepine and tricyclic overdose, flumazenil can unmask the convulsant properties of TCAs and increase the severity of arrhythmias induced by them.

The arrhythmias induced by TCAs often respond to sodium bicarbonate, but if they do not, intravenous glucagon can be used. Adrenaline and magnesium sulphate can also be used.

Answer Statistics

1

4%

2

6%

3

21%

4

2%

5

69%

Times answered: 276