Eletrocardiographic evaluation of continuous lidocaine infusion in dogs anesthetized with sevoflurane

Abstract Background The purpose of this study was to evaluate the effects of continuous infusions of lidocaine on electrocardiographic variables in dogs anesthetized with sevoflurane. Twenty dogs were divided into two experimental groups: a control group (CG) and a lidocaine group (GL). The animals were anesthetized using a face mask with sevoflurane. Subsequently, an intravenous bolus of lidocaine (2 mg/kg) was administered to the GL, followed by the start of continuous infusion (100 µg/kg/minute). For the CG, the same methodology was used, in which lidocaine was replaced with 0.9% NaCl saline solution in identical volumes, rates and routes. Observations of the variables of interest began before the administration of lidocaine or 0.9% NaCl (MB) and 20, 40, 60 and 80 minutes after the start of continuous infusion (M20, M40, M60 and M80, respectively). The following variables were studied: heart rate and systolic, mean and diastolic blood pressure. Electrocardiographic measurements: P-wave, P-R interval, Q-R-S length, R-wave, and Q-T interval. Results No significant differences were observed in the mean values ​​between time points within each group or between groups for any of the variables studied. Conclusions continuous infusion of lidocaine did not promote important changes in the cardiac electrophysiology of dogs anesthetized with sevoflurane.