Arrhythmias & Conduction Blocks

• Any unstable tachyarrhythmia needs synchronized cardioversion immediately (sedate when time allows).
• AF rate control via β-blocker/diltiazem (avoid in HFrEF — amiodarone/digoxin); regular narrow-complex: vagal first, then adenosine 6→12→12 mg.
• Treat wide-complex rhythms as VT until proven otherwise (Brugada); stable monomorphic gets amiodarone or procainamide, torsades gets magnesium 2 g and overdrive pacing.
• Symptomatic bradycardia: atropine 1 mg, transcutaneous pacing, dopamine or adrenaline infusion, then pacing wire.

Arrhythmia / conduction block

First tests: 12-lead ECG, Sodium, potassium, bicarbonate, urea and creatinine, Magnesium.

Only if indicated: High-sensitivity cardiac troponin, TSH and free T4, Bedside echocardiography, Relevant drug level / toxicology tests.

Repeat monitoring: Continuous rhythm monitoring.

After return of spontaneous circulation

First tests: 12-lead ECG, Arterial blood gas, Blood glucose, Sodium, potassium, bicarbonate, urea and creatinine, Bedside echocardiography.

Only if indicated: Cause-directed CT imaging, EEG.

Repeat monitoring: Multimodal neurological assessment.

• Advanced Cardiac Life Support Tachycardia Treatment Pathway
• Advanced Cardiac Life Support Bradycardia Treatment Pathway
• Advanced Cardiac Life Support Pulseless Arrest Pathway
• Differentiating Narrow QRS Complex Tachycardias
• Differentiating Wide QRS Complex Tachycardias
• Treating Atrial Fibrillation and Atrial Flutter (See Chapter 91 Common Drug Dosages and Side Effects)