Peri-arrest arrhythmias

Question 1

Why do you deliver synchronised cardioversion?

Answer 1

If the shock coincides with the T wave, it can lead to VF

Question 2

What are the 4 life-threatening features of peri-arrest arrhythmias?

Answer 2

• Shock
• Syncope
• Myocardial ischaemia (chest pain)
• Severe heart failure (pulmonary oedema)

Question 3

In tachyarrhythmias with life-threatening features, what is the management?

Answer 3

• Up to 3 synchronised DC shock attempts with sedation or anaesthesia
• Amiodarone 300mg IV over 10–20 mins
• Repeat synchronised DC shock

Question 4

In tachyarrhythmias without life-threatening features, how do you assess?

Answer 4

• QRS broad/narrow

Question 5

In tachyarrhythmias without life-threatening features, how do you manage a broad QRS?

Answer 5

• Broad irregular = AF with BBBB, polymorphic VT > IV magnesium sulfate 2g over 10 mins
• Broad regular = VT or SVT with BBB > IV amiodarone 300mg over 10–60 min followed by IV amiodarone 900mg over 24h

Question 6

In tachyarrhythmias without life-threatening features, how do you manage a narrow QRS?

Answer 6

• Regular (SVT) = vagal manoeuvres or adenosine 6mg > 12mg > 18mg IV bolus or verapamil 2.5–5mg IV over 2m/beta-blocker e.g., metoprolol IV 2.5mg boluses (15mg)
• Irregular (AF) = rate control (beta-blocker), ?digoxin or amiodarone if heart failure, anticoagulate if >48h duration

Question 7

In bradyarrhythmias with life-threatening features, what is the management?

Answer 7

• Atropine 500mcg IV every 3–5 mins max 3mg.
• Isoprenaline 5mcg/min IV
• Adrenaline 2–10mcg/min IV
• Aminophylline
• Dopamine
• Glucagon (beta-blocker/CCB overdose)
• Glucopyrolate instead of atropine
  OR
• Transcutaneous pacing > transvenous pacing