Effects of amiodarone infusion on clinical parameters in the cardiac intensive care unit: what does it do to heart rate and oxygen delivery?

Background: Amiodarone is a frequently used medication in paediatric patients to manage atrial and ventricular arrhythmias, but its acute haemodynamic effects, particularly in children, remain underexplored. This retrospective, single-centre study aimed to characterise the clinical impact of amiodarone intravenous infusions on heart rate, blood pressure, oxygen delivery, and transaminase levels within the first 48 hours of amiodarone initiation in paediatric cardiac ICU patients.

Methods: Single-centre, retrospective study of patients receiving amiodarone infusions, with measurements taken at baseline and at various intervals up to 48 hours after initiation. The primary outcome was the effect on heart rate, while secondary outcomes included blood pressure, arterial saturation, near-infrared spectroscopy values, central venous pressure, and transaminase levels. Several types of analysis models were employed to assess the results.

Results: Data were collected from 87 paediatric patients. No significant changes in liver enzymes, blood pressure, or renal oxygen extraction were observed. These findings provide novel insights into the acute haemodynamic effects of amiodarone infusions in paediatric patients, suggesting that while amiodarone significantly lowers heart rate, it does not substantially affect oxygen delivery or necessitate increased vasoactive support.

Conclusion: Amiodarone infusions are associated with a significant decrease in heart rate without greatly impacting oxygen delivery or requiring increased vasoactive support. Heart rate decreases most until a cumulative dose of 30,000 mcg/kg, and heart rate decrease is most pronounced in those with ventricular tachycardia.