Ventricular fibrillation and cardiac arrest
Disorganised ventricular contractions above 300 bpm – no haemodynamics, clinical death follows. Per AHA ACLS 2020 and ERC 2021: immediate CPR, biphasic defibrillation 200 J, adrenaline 1 mg IV every 3–5 minutes. For refractory VF/polymorphic VT after the third shock – amiodarone 300 mg IV bolus, repeat 150 mg if needed. Lidocaine is an alternative when amiodarone is unavailable.
ICD-10 I46.92 drugs
Also known as: VF, Sudden cardiac arrest
Drugs used for this condition
- BAmiodaroneFirst line · Class III antiarrhythmics (Vaughan Williams)Per AHA ACLS 2020 and ERC 2021, in refractory VF or polymorphic VT after the third ineffective shock, give amiodarone 300 mg IV bolus. If arrhythmia persists, repeat 150 mg. Lidocaine 1–1.5 mg/kg is the alternative when amiodarone is unavailable. The large ALPS 2016 RCT showed no significant effect of either agent on survival to hospital discharge, but amiodarone reduced rhythm recurrence during resuscitation.
- BLidocaineSecond line · Amide-type local anaesthetic and class Ib antiarrhythmic (systemic use, codes C01BB01 and N01BB02)In cardiac arrest with ventricular fibrillation or pulseless ventricular tachycardia the 2021 ERC advanced life support guideline places amiodarone 300 mg after the third defibrillator shock, with a repeat dose of 150 mg after the fifth. Lidocaine 100 mg appears there as the alternative when amiodarone is unavailable or a decision was made not to use it, with a further 50 mg dose. Neither drug has convincingly raised survival to hospital discharge, and both stay in the protocol for rhythm restoration rather than for a proven gain in outcome. The order of actions does not change: uninterrupted chest compression and early defibrillation give more than any antiarrhythmic.
How to read tiers A–F
Evidence tiers belong to the drug-indication pair, not to the drug as a whole: the same substance can be A for one condition and F for another.
- AStrong evidence – first or second line in international guidelines
- BRecommended in selected cases
- CStudy data contradict each other
- DBenefit not proven, no documented harm
- FDocumented harm, or risk without benefit