Amide Local Anesthetic Alterations of Effective Refractory Period Temporal Dispersion

Publisher Website
Google Scholar
Abstract
The hemodynamic and electrophysiologic effects of bupivacaine, etidocaine, mepivacaine, and lidocaine were investigated in 32 pentobarbital-anesthetized adult mongrel dogs. Following equipotent dosing, all four agents produced similar hemodynamic effects: decrease in stroke volume and cardiac output, heart rate slowing, increase in systemic vascular resistance, and increases in pulmonary arterial pressure (PAP) and pulmonary capillary wedge pressure (PCWP). The effects of the various agents on the ECG were different. Compared with the control period, mepivacaine and lidocaine produced slight increases and etidocaine. Six of seven bupivacaine, six of seven etidocaine, two of eight mepivacaine, and none of eight lidocaine animals sustained a polymorphic, undulating ventricular tachycardia similar to Torsades de Pointes following burst ventricular pacing. The results of this study suggest that bupivacaine, etidocaine, and occasionally mepivacaine can result in a Torsades de Pointes-like syndrome following intravenous administration. The magnitude of ERP temporal dispersion differences between the various agents appears to explain their differential arrthymogenicity.