||antiarrhythmic: Class III
prolongs refractory period in atria and ventricles thus effective for arrhythmias of various origins
- decreases SA automaticity and conduction through AV node
- Multiple dosing regimes in literature; RECOMMEND:
- Bolus Dose:
- 150-300 mg IV (maximum infusion rate 30 mg/min)
- Continuous Infusion:
- 900-1200 mg over 24 hours (37.5-50 mg per hour)
- Breakthrough arrhythmias:
- 150 mg IV (maximum infusion rate 30 mg/min)
- 450 mg/250 ml dextrose 5% or sodium chloride 0.9% (1.8 mg/ml)
- Continuous infusions should be prepared in non-PVC bags to prevent adsorption of amiodarone into bag.
- Use of a 0.2 or 0.22 micron filter is recommended for intermittent and continuous infusions.
- Bolus doses: in 100 ml D5W over 10 min (maximum infusion rate 30 mg/min)
- Continuous infusion: in 500 ml D5W (in non PVC bag) over 24 hours
- Cardiac Arrest:
First dose: Give 300 mg (6 mL) IV direct UNDILUTED. A filter is not required for IV direct administration.
Second dose: If patient remains in pulseless ventricular tachycardia or ventricular fibrillation 5 minutes after the first dose, give a second dose of amiodarone 150 mg (3 mL).
- Adverse events:
- arrhythmias including bradycardia and AV blocks
- prolonged QT interval (with potential for Torsades des pointes)
- hepatitis, elevation of liver function tests
- peripheral myopathy or tremors, headache, sleep disturbances
- nausea, anorexia, constipation
- Long term effects:
- corneal microdeposits, photophobia, visual blurring, halovision
- interstitial pneumonitis
- blue-grey skin discoloration
- hypo or hyperthyroidism
- in complete heart block or type II second degree heart block unless functional pacemaker in place (can suppress a ventricular escape rhythm)
- Amiodarone should not be used in patients with polymorphic ventricular tachycardia as it is associated with a prolonged QT interval which is made worse by antiarrhythmic agents
- amiodarone + digoxin = increased digoxin levels
- amiodarone + warfarin = increased warfarin effect
- amiodarone + beta blockers = increased effects of both drugs
- amiodarone + calcium channel blockers = increased effects of both drugs
- amiodarone + procainamide = increased procainamide effect
- ECG rhythm
- Heart rate
- QT interval
- Blood pressure and pulse
- liver enzymes
|Adult Critical Care Protocol:
- The first (300 mg) and second (150 mg) doses of amiodarone may be given for pulseless ventricular tachycardia or ventricular fibrillation by Medical Directive by a certified Adult Critical Care Nurse.
- May be administered by IV infusion by an Adult Critical Care Nurse.
- Continuous infusions must be administered by infusion device and the pump library must be enabled.