Amiodarone for use in Paediatric Cardiology
This guideline covers the use of amiodarone infusion in ward 23B (paediatric cardiology) and covers administration via a both central line and peripheral line access.
Purpose of guideline
This guideline covers the use of amiodarone infusion in ward 23B (paediatric cardiology) and covers administration of amiodarone infusion via either a central line or peripheral line.
Please note there are different prescribing and administration guidelines for central and peripheral line administration within the document.
The use of amiodarone and the appropriate dose will be determined by the consultant cardiologist and/or cardiac surgeon only.
Where there is significant ventricular dysfunction the infant / child will be admitted to PICU for commencement of the amiodarone infusion and starting at a reduced dose of 10 micrograms /kg/minute.
Commencement of IV amiodarone outside of PICU or the Paediatric Cardiology ward at Starship should only be considered after discussion with the Paediatric Cardiologist on call, and only given in a monitored environment, with consideration of retrieval of the child to Starship Hospital.
Mechanism of Action
Complex drug with a broad spectrum of activity. Predominately Class III antiarrhythmic drug but also has actions similar to antiarrhythmic classes Ia, II and IV.
Main electrophysiological action is prolongation of the action potential and refractoriness of all cardiac structures resulting in reduction of membrane excitability in myocardial tissue.
prolongs the myocardial cell action potential in phase 3 (repolarisation) and refractory period of atrial, nodal and ventricular tissues
Increases the refractory period via sodium and potassium channel effects.
Slows the intracardiac conduction of the cardiac action potential via sodium-channel effects5
Indications
Control of ventricular and supraventricular arrhythmias including those associated with Wolff Parkinson - White syndrome
Dose
| INTRAVENOUS2 | |
| 1. For haemodynamically stable infant/child | |
| Loading dose | 25 micrograms/kg/minute for 4 hours, then |
| Maintenance | 5 to 15 micrograms/kg/minute (Do not exceed dose of 1200mg/24 hours) |
| 2. Where there is significant ventricular dysfunction Infant/child should be in PICU for commencement of the amiodarone infusion | |
| Loading Dose | 10 micrograms/kg/minute, then |
| Maintenance | 5 to 10 micrograms/kg/minute (do not exceed dose of 1200 mg / 24 hours) |
Central Line Prescription and Administration
| CENTRAL LINE Prescription | |
| Prescribe on the fluid chart with a cross reference to the infusion on the medication chart stating "IV amiodarone charted on fluid chart". The prescription on the fluid chart must include: - Amount of amiodarone in mg to add to glucose 5% in 50 mL - Dose in micrograms /kg /minute - Rate in mL/ hour - Administered via CVL The recommended maximum concentration of prepared solution is 6 mg/mL. Concentrations up to 12 mg/mL have been used and are done at the prescriber's discretion. The concentration in the syringe is altered to administer the prescribed dose. | |
| Amount of amiodarone to be added to diluent to make up to 50 mL | 1 mL/hour = |
| ≤ 10kg: 30 mg/kg | 10 microgram/kg/min |
| 11‐ 40kg: 15 mg/kg | 5 microgram/kg/min |
| >40kg: 7.5 mg/kg | 2.5 microgram/kg/min |
| CENTRAL LINE Administration | |
| Check your preparation using the examples above. - Central line administration is preferred. - Dilute with glucose 5% only - Not compatible with heparin or sodium chloride. - Check your preparation using calculation above or PICU drug infusion charts - <30kg or >30kg | |
| To set up the pump: In Guardrails choose 'Amiodarone Central line' for the correct weight range on the pump: 1. Input the amount of amiodarone (in milligrams) to be made up to 50mLs 2. Input the child's weight. 3. Use up and down buttons to set the correct rate (mLs/hr) Guardrails will calculate and display delivered dose (micrograms/kg/minute). |
Peripheral Line Prescription and Administration
| PERIPHERAL LINE Prescription |
| Prescribe on the Fluid balance chart with a comment on the drug chart stating "IV amiodarone charted on fluid balance chart". The prescription on the Fluid balance chart must include: - Amount of amiodarone to add, in mg - Diluent and final volume of infusion. - Dose in micrograms /kg /minute. - Rate in mLs/ hour. - Given via Peripheral IV The maximum concentration for peripheral administration is 2 mg/mL (2000 micrograms /ml). Solutions of 0.6 mg/mL and less are unstable and should not be used. A standard concentration of 100 mg Amiodarone in 50 mLs 5% glucose (2 mg/mL) is ALWAYS used. The rate is altered to administer the prescribed dose. To calculate rate in mLs/hour to administer required dose use the calculation below: |
| PERIPHERAL LINE Administration |
| Check your preparation using the example above. - Central line administration is preferred - Dilute with glucose 5% only - Not compatible with heparin or sodium chloride. |
| To set up the pump In Guardrails choose 'Amiodarone PERIPH' on the pump (4th option for amiodarone) 1. Input solution details (100 mg in 50 mL) 2. Input child's weight 3. Use up and down buttons to set the correct DOSE (micrograms/kg/minute) Guardrails will calculate and display the correct rate (mL/hr) |
Observation and documentation
Child should be in 23B Intensive Observation Area (IOA) with continuous nursing observation and monitoring.
Prior to administration take baseline blood levels for:
electrolytes and FBC.
liver function and thyroid function.
Prior to administration document:
blood pressure and heart rate
respiratory rate
oxygen saturations. Repeat every 10 minutes for first hour, then hourly.
baseline CXR
Monitor ECG and saturations continuously. Perform daily 12-lead ECG.
Peripheral infusions: hourly observation of cannula site, as sloughing of the skin and tissue necrosis can occur with infiltration and extravasation.
Perform baseline pulmonary function tests and baseline ophthalmic assessment if anticipating long term treatment with amiodarone (in consultation with cardiologist).
Special considerations
Handover between staff is important: discussion with medical staff needs to take place at both morning and evening handover and also between nursing staff at each shift change:
To confirm that the infusion is to continue
To check the current dose (in micrograms/kg/minute) and rate (in mL/hour)
To independently double check the infusion dose calculation by both nursing staff members
Confirm appropriate prescription and administration used according to type of IV access (CVL or PIV)
Contraindications and precautions
| Contraindications1 | |
| Except in cardiac arrest | Sinus bradycardia, sino-atrial heart block Unless pacemaker fitted avoid in severe conduction disturbances or sinus node disease Thyroid dysfunction; iodine sensitivity |
| Avoid intravenous use in | Severe respiratory failure Circulatory collapse or severe arterial hypotension Avoid bolus injection in congestive heart failure or cardiomyopathy Avoid rapid loading after cardiac surgery |
| Precautions1 | |
| - Liver-function and thyroid-function tests recommended before treatment - Hypokalaemia (measure serum-potassium before treatment) - Heart failure, severe bradycardia and conduction disturbances in excessive dosage - IV use may cause moderate and transient fall in blood pressure (circulatory collapse precipitated by rapid administration or overdosage) - Severe hepato-cellular toxicity (monitor transaminases closely) - Benzyl alcohol - containing injections in preterm infants have been associated with the "gasping syndrome" |
For detailed information about this drug including clinical pharmacology, please see Medsafe Data Sheet in Reference viewer.
Possible adverse effects
Negative inotropic effect
Prolongation of QT interval
Nausea, vomiting, taste disturbances, raised serum transaminases, jaundice, bradycardia, sleep disorders, corneal microdeposits, venous irritation (peripheral), photosensitivity
Pulmonary toxicity
Hypothyroidism and hyperthyroidism - due to iodine content of amiodarone.
Hepatotoxicity
Before treatment, measure baseline then routinely monitor:
thyroid function
liver function
CXR
If anticipating long term treatment with amiodarone (in consultation with cardiologist), perform baseline pulmonary function tests and baseline ophthalmic assessment for corneal micro deposits
Drug interactions
Amiodarone is a CYP 3A4 inhibitor, therefore has many drug interactions which can result in toxicity. Some important examples include:
Amiodarone and digoxin: reduce the digoxin dose to half maintenance. If loading digoxin, use full digoxin loading dose and half maintenance dose; take digoxin levels
Amiodarone and some QT prolonging drugs may induce torsades de pointes arrhythmias. These drugs should not be used with amiodarone: e.g. Class 1A antiarrhythmics, sotalol, erythromycin, mexiletine, citalopram
Amiodarone may interact with some drugs lowering heart rate or causing conduction disturbances. Caution is advised if also using: beta blockers or calcium antagonists
Amiodarone and drugs affecting electrolyte levels (especially potassium) should be used with caution: diuretics, corticosteroids, amphotericin, senna (stimulant laxative) are not recommended
Amiodarone may interact with other drugs leading to altered levels of those drugs e.g. warfarin, sildenafil, flecainide, phenytoin, cyclosporine, fentanyl, midazolam.
As amiodarone has a long half life (up to 60 days), these drug interactions may potentially occur some time after amiodarone treatment has stopped.
For detailed information about drug interactions please see Medsafe Data Sheet - IV Amiodarone