BLOOD GAS ANALYSIS AND CARDIOPULMONARY PARAMETERS OF CONTINUOUS RATE INTRAVENOUS INFUSION OF LIDOCAINE IN ISOFLURANE ANESTHETIZED CALVES UNDERGOING MECHANICALLY VENTILATION

Abstract

The aim of this study is to evaluate the cardiorespiratory and acid-base effects in mechanically breathing calves anesthetized by isoflurane and followed by continuous rate infusion of lidocaine. For such, eight male animals with six and eight months old, distributed in two experimental groups lidocaine group (LG) and the control group (CG) will be used. The animals will receive xylazine (0.07 mg/kg;IM) and 15 minutes later, ketamine (1.5 mg/kg; IV) associated with midazolam (0.05 mg/kg; IV). Immediately after the animals will be intubated and submitted to the isoflurane anesthesia (1.3 MAC) and subjected to mechanical ventilation. After 20 minutes, the animals of the LG will receive a bolus of 2.0 mg/kg of lidocaine followed by continuous rate infusion of 100 ¼g/kg/min. At the animals of the CG the same amount of sodium chloride 0.9% will be carried out. The observations of the variables, in both groups, will begin before (MB) and 15 minutos after (MX) xilazine administration and immediately before (M20) and 20 minutes after (M40) lidocaine or sodium chloride 0.9% administration. New mensurations will be carried out during 60 minutes (in intervals of 20 minutes) M60, M80 e M100, respectively. The recovery time will be evaluated and recorded until de animals have adopted sternal and quadrupedal position. The statistical analysis will be carried out through ANOVA following Bonferroni or t de Student test, considering the level of significance of 5% (p<0.05).