title: Alfentanil-midazolam anaesthesia has no electrophysiological effects upon the normal conduction system or accessory pathways in patients with Wolff-Parkinson-White syndrome.
abstract: The effects of alfentanil-midazolam anaesthesia upon the electrophysiologic (EP) properties of normal atrioventricular (A-V) and accessory pathway (AP) conduction were studied in eight patients with Wolff-Parkinson-White syndrome during accessory pathway surgical ablation. The presence of an AP was confirmed by preoperative EP studies. Anaesthesia was induced with alfentanil (50 micrograms.kg-1) and midazolam (0.15 mg.kg-1) and maintained with an alfentanil infusion (2 micrograms.kg-1.min-1) and intermittent boluses of midazolam (1-2 mg q 15 min, PRN). Following sternotomy, a baseline EP study was performed which consisted of effective refractory period (ERP) and shortest cycle length (SCC) measurement during antegrade conduction in the AV and AP, as well as during retrograde conduction in the AP. Comparison with preoperative EP studies indicated that the administration of alfentanil-midazolam anaesthesia had no effect upon conduction or ERP in either pathway. Haemodynamic stability occurred throughout the surgical procedure with no tachyarrhythmias. We conclude that a combination of alfentanil-midazolam is suitable for general anaesthesia in patients undergoing ablative procedures for accessory pathways.
authors.affiliation: Department of Anaesthesia, University Hospital, London, Ontario.
authors.forename: M D
authors.initials: MD
authors.lastname: Sharpe
authors.forename: W B
authors.initials: WB
authors.lastname: Dobkowski
authors.forename: J M
authors.initials: JM
authors.lastname: Murkin
authors.forename: G
authors.initials: G
authors.lastname: Klein
authors.forename: G
authors.initials: G
authors.lastname: Guiraudon
authors.forename: R
authors.initials: R
authors.lastname: Yee
mesh_terms: D000328:Adult; D015760:Alfentanil / Q000494:pharmacology*; D000771:Anesthesia, Intravenous; D016280:Atrial Function, Right / Q000187:drug effects; D001283:Atrioventricular Node / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002496:Central Venous Pressure / Q000187:drug effects; D004562:Electrocardiography; D004594:Electrophysiology; D005260:Female; D006329:Heart Conduction System / Q000187:drug effects* / Q000601:surgery; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008874:Midazolam / Q000494:pharmacology*; D012032:Refractory Period, Electrophysiological / Q000187:drug effects; D016278:Ventricular Function, Right / Q000187:drug effects; D014927:Wolff-Parkinson-White Syndrome / Q000503:physiopathology* / Q000601:surgery
chemical_list: D015760:Alfentanil; D008874:Midazolam