AMIODARONE (Cordarone)

prolongs refractory period in atria and ventricles thus effective for arrhythmias of various origins

• Decreases SA automaticity and conduction through AV node

Indicated for treatment of ventricular and supraventricular tachyarrhythmias.

• 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 a 0.2 or 0.22 micron filter 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). 

QTc prolongation and Known Risk of Torsades de Pointes (TdP)

Amiodarone prolongs QT interval and is clearly associated with a known risk of TdP, even when taken as recommended. 

Amiodarone should only rarely, if ever, be given to patients with Congenital Long QT Syndrome (CLQTS) becasue the danger is clear. However, when no alternative safe drug is available and the illness is severe, some patients with CLQTS may be treated with amiodarone by physicians with expertise in the treatment of arrhythmias. 

• 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
• Known hypersensitivity to any of the components of amiodarone
• Dose adjust in hepatic failure; guidelines have not been established

• Arrhythmias including bradycardia and AV block
• Prolonged QT interval (with potential for Torsades des Pointes)
• Hepatitis (potentially fatal), elevation of liver function tests, ammonia
• Thrombocytopenia, abnormal coagulation parameters, anemia
• Peripheral neuropathy/myopathy or tremors
• Headache
• Sleep disturbances
• Nausea, anorexia, constipation, diarrhea
• Anaphylaxis
• Infection site reactions
• Abnormal thyroid function (hyper or hypo)

Long term effects:

• corneal microdeposits, photophobia, visual blurring, halovision
• interstitial pneumonitis
• blue-grey skin discoloration
• hypo or hyperthyroidism

Amiodarone is a vesicant that can cause progressive and severe tissue destruction. 

• 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
• IV site
• Thyroid function tests for prolonged use

• Amiodarone is a vesicant; ensure line patency before and after administration.
• Monitor peripheral site closely and document Infiltration and Phlebitis scale Q1H. 
• 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.