Anesthesia and sedation strategies in electrophysiology: General concepts

Numerous procedures are carried out in the cardiac electrophysiology laboratory including catheter ablation for various arrhythmias and implantation of devices such as pacemakers and implantable cardioverter-defibrillators (ICD). Patients undergoing these procedures pose unique challenges to the anesthetist as they have serious cardiovascular conditions like unstable arrhythmias, coronary artery disease and poor cardiac function, often with left ventricular ejection fraction less than 35 %. Many of these procedures can be carried out under local anesthesia with conscious sedation administered by a trained nurse. However, monitored anesthesia care with varying levels of sedation provided by trained anesthesia personnel is preferable in patients with multiple comorbidities and severe cardiac conditions. General anesthesia is needed for patient populations such as pediatric patients, those with poor functional status who cannot lie on their back and for complex catheter ablation procedures which require minimal patient movement for prolonged durations. Midazolam and fentanyl are the commonly used agents for conscious sedation. Propofol, etomidate or ketamine are commonly used for deeper sedation or general anesthesia. The effects of anesthetic drugs on the cardiac conduction system should be kept in mind as they can interfere with identifying arrhythmias during electrophysiological studies.