title: Cardiac electrophysiologic effects of lidocaine and bupivacaine.
abstract: The cardiac electrophysiologic effects of bupivacaine (B) and lidocaine (L) were evaluated in an isolated rabbit Purkinje fiber-ventricular muscle model to determine the effects of a) progressively increasing and b) decreasing concentrations of B and L on transmembrane action potentials. Bupivacaine (3 and 5 micrograms/ml) significantly decreased diastolic resting potential, maximum rate of depolarization, and action potential amplitude. Lidocaine (10-20 micrograms/ml) also decreased maximum rate of depolarization and action potential amplitude, but the decreases were significantly different from those produced by B. High concentrations of B (30 micrograms/ml) and L (100 micrograms/ml) resulted in delayed conduction between Purkinje fibers and ventricular muscle cells and, ultimately, conduction blockade. The duration of conduction blockade was significantly longer with B than with L. The results of this study indicate that B produces electrophysiologic changes in cardiac tissue that may produce ventricular arrhythmias of a reentrant type.
authors.affiliation: Department of Anesthesia, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115.
authors.forename: R A
authors.initials: RA
authors.lastname: Moller
authors.forename: B G
authors.initials: BG
authors.lastname: Covino
mesh_terms: D000200:Action Potentials; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000139:chemically induced; D002045:Bupivacaine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006321:Heart / Q000187:drug effects*; D006327:Heart Block / Q000139:chemically induced; D006329:Heart Conduction System / Q000187:drug effects*; D006352:Heart Ventricles / Q000187:drug effects; D007275:Injections, Intravenous; D008012:Lidocaine / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D011690:Purkinje Fibers / Q000187:drug effects*; D011817:Rabbits
chemical_list: D008012:Lidocaine; D002045:Bupivacaine