The Use of Intravenous Lidocaine in the Setting of Chronic Dofetilide Overdose: A Case Report.

Managing the risks and consequences of long QT syndrome can be challenging. Multiple factors contribute to the prolongation of the heart-rate corrected QT (QTc) interval including many drug-drug and drug-disease state interactions. Current literature is often focused on avoiding dysrhythmias with limited guidance on acute management strategies. Here we describe a case of QTc prolongation to 616 msec (Bazett's formula) in the setting of chronic dofetilide overdose due to a possible prescription error. Our case was complicated by alcohol withdrawal and electrolyte disturbances that progressed to patient cardiac arrest in the emergency department. Dofetilide overdose was identified through pharmacist-initiated medication reconciliation and lidocaine was recommended as an alternative to amiodarone during advanced cardiac life support (ACLS). This case highlights the importance of reviewing outpatient medication records as well as avoiding drug-drug interactions during ACLS. Due to the potential for additive QTc prolongation, we recommend using lidocaine as the preferred antiarrhythmic in ACLS algorithms where drug induced QTc prolongation is suspected.