What is the recommended dose of Amiodarone (anti-arrhythmic medication) for an adult patient experiencing a life-threatening arrhythmia in advanced life support?

Amiodarone Dosing in Advanced Life Support

For ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) unresponsive to CPR, defibrillation, and vasopressor therapy, administer an initial dose of 300 mg IV/IO, followed by one additional dose of 150 mg IV/IO if the arrhythmia persists. 1

Clinical Context and Indications

Amiodarone should be considered specifically for shock-refractory VF or pulseless VT after the patient has already received:

• High-quality CPR
• Defibrillation attempts
• Vasopressor therapy (epinephrine or vasopressin) 1

The evidence shows amiodarone improves short-term survival to hospital admission compared to placebo or lidocaine in this specific population, though it does not improve survival to hospital discharge. 1

Dosing Algorithm

Initial Dose

• 300 mg IV/IO administered as a bolus 1
• Can be mixed in 100 mL D5W for infusion 2
• Administer rapidly during cardiac arrest (the 10-minute infusion time used for hemodynamically unstable VT with a pulse does not apply during pulseless arrest) 2

Second Dose (If Needed)

• 150 mg IV/IO if VF/pulseless VT persists after the initial dose 1
• This is the only supplemental dose recommended during cardiac arrest 1

Route of Administration

• IV or intraosseous (IO) routes are both acceptable 1
• Limited experience exists with IO administration, but it has been used without known adverse effects 1

Important Clinical Considerations

Timing in the Algorithm

Amiodarone is a Class IIb recommendation (may be considered), meaning the benefit-to-risk ratio is less well established. 1 It should only be given after:

1. Multiple defibrillation attempts
2. Epinephrine administration
3. Continued high-quality CPR 1

Alternative Agent

If amiodarone is unavailable, lidocaine may be considered as an alternative:

• Initial dose: 1 to 1.5 mg/kg IV
• Additional doses: 0.5 to 0.75 mg/kg IV every 5-10 minutes
• Maximum total dose: 3 mg/kg 1

However, lidocaine has no proven short- or long-term efficacy advantage and is only recommended when amiodarone is not available. 1

Common Pitfalls and Adverse Effects

Hypotension Risk

• Hypotension is the most common adverse effect, occurring in approximately 26% of patients receiving IV amiodarone 3
• This is primarily attributed to vasoactive solvents (polysorbate 80 and benzyl alcohol) in the IV formulation 1
• Administer vasopressors before amiodarone when possible to prevent hypotension 1

Bradycardia and Conduction Abnormalities

• Bradycardia occurs in approximately 4.9% of patients on IV therapy 1
• Monitor for heart block and AV conduction delays 1

Dosing Errors to Avoid

• Do not exceed 300 mg for the initial dose during cardiac arrest 1
• Do not give more than one 150 mg supplemental dose during the arrest 1
• Do not confuse cardiac arrest dosing with the dosing for hemodynamically stable arrhythmias (which uses slower infusion rates) 2

Post-Resuscitation Management

If return of spontaneous circulation (ROSC) is achieved after amiodarone administration during cardiac arrest:

• Transition to a maintenance infusion of 1 mg/min for 6 hours, then 0.5 mg/min for 18 hours 2
• Use concentrations of 1-6 mg/mL (central line preferred for concentrations >2 mg/mL) 2
• Monitor closely for hypotension, bradycardia, and QT prolongation 1