Sun21November0735PM 5

A 64-year-old man with a history of depression self presents to the Emergency department four hours after taking an overdose of his antihypertensive medication, which he thinks is a beta blocker. He states he has been feeling light headed for a few hours but has not noted any other symptoms.

His blood pressure is recorded as 96/60 mmHg and his pulse is 45. A 12 lead ECG reveals a regular rhythm with normal QRS morphology. The PR interval is prolonged but there are no non-conducted P waves.

From the options below, which is the first step in this patient's management?

(Please select 1 option)

Atropine This is the correct answer

Observation Incorrect answer selected

Temporal transvenous cardiac pacing

Activated charcoal

Glucagon

Explanation

Overdose of beta blockers or calcium channel blocker can lead to significant bradycardia.

If taken within one hour of presentation, activated charcoal should be tried.

If there is symptomatic bradycardia atropine should be used in the first instance.

Glucagon can be effective but this should be tried after atropine.

Pacing may be necessary if these drug treatments fail. High-dose insulin is being used more readily to treat beta blocker overdose in those who are haemodynam- ically unstable. It can be titrated to maintain a stable blood pressure but typically requires doses much higher than those used to treat diabetic ketoacidosis.

Intravenous lipid infusion has been used in various drug overdoses and has particular relevance in local anaesthetic toxicity. ToxBase recommends consider- ing IntraLipid in patients with a history of overdose of beta blockers, who have cardiotoxic symptoms not responding to conventional treatment.

Therefore the correct answer here, in a patient who has symptomatic bradycardia more than one hour after a probable beta blocker overdose is atropine.

Answer Statistics

1

24%

2

35%

3

3%

4

2%

5

38%

Times answered: 279