EFFECTS OF PROPOFOL OR ISOFLURANE ANESTHESIA ON CARDIAC CONDUCTION INCHILDREN UNDERGOING RADIOFREQUENCY CATHETER ABLATION FOR TACHYDYSRHYTHMIAS

Background: To determine suitability for ablation procedures in childr en, two commonly used anesthetic agents were studied: propofol and iso flurane. Methods: Twenty patients presenting for a radiofrequency cath eter ablation procedure were included and randomly assigned to two gro ups. A baseline electrophysiology study was performed during anesthesi a with thiopental, alfentanil, nitrous oxide, and pancuronium in all p atients. At the completion of the baseline electrophysiology study (EP S), 0.8-1.2% isoflurane was administered to patients in group 1 and 2 mg/kg propofol bolus plus an infusion of 150 mu g . kg(-1) . min(-1) w as administered to patients in group 2. Nitrous oxide and pancuronium were used throughout the procedure. After 30 min of equilibration, bot h groups underwent a repeat EPS. The following parameters were measure d during the EPS: cycle length, atrial-His interval, His-ventricle int erval, corrected sinus node recovery time, AV node effective refractor y period, and atrial effective refractory period. Using paired t tests , the electrophysiologic parameters described above measured during pr opofol or isoflurane anesthesia were compared to those measured during baseline anesthesia. Statistical significance was accepted as P < 0.0 5. Results: There was no statistically significant difference in the r esults obtained during baseline anesthesia when compared with those me asured during propofol or isoflurane anesthesia. Conclusions: Neither propofol nor isoflurane anesthesia alter sinoatrial or atrioventricula r node function in pediatric patients undergoing radiofrequency cathet er ablation, compared to values obtained during baseline anesthesia wi th alfentanil and midazolam.