Estudo comparativo entre solu??es a 0,5% de levobupivacaína, bupivacaína em excesso enantiomérico de 50% e bupivacaína racêmica em anestesia peridural para cirurgia de abd?men inferior

摘要

BACKGROUND AND OBJECTIVES: With the purpose of finding a local anesthetic agent safer than racemic bupivacaine, several animal studies have been performed with its isomers. This study aimed at evaluating, for one hour after injection, the efficacy of 50% enantiomeric excess bupivacaine as compared to levobupivacaine and racemic bupivacaine for epidural anesthesia in patients submitted to lower abdominal procedures. METHODS: After the Research Ethics Committee approval, 87 patients aged 18 to 65 years, physical status ASA I and II, undergoing lower abdominal procedures were included in this randomized double-blind study. Patients were distributed in three groups which received 27 mL (including test dose) of local anesthetics with epinephrine (1:200,000) and fentanyl (100 μg) solutions. Group I was given 0.5% levobupivacaine, group II received 50% enantiomeric excess 0.5% bupivacaine, and group III received 0.5% bupivacaine. Monitoring consisted of pulse oximetry, cardioscopy and noninvasive blood pressure. Motor and sensory block profiles were evaluated, in addition to the incidence of side effects. Unidentified local anesthetic vials were numbered, and the randomized distribution list was opened only at the end of the experiment. RESULTS: There were no significant differences regarding height and physical status between groups. There was a significant age difference in group I. Hemodynamic parameters were similar between groups. Motor block intensity was significantly lower in group I as compared to groups II and III. CONCLUSIONS: All groups presented adequate motor and sensory block for surgery, with few side effects, suggesting that these solutions are effective for epidural anesthesia for lower abdominal procedures. Levobupivacaine produced less motor block as compared to the other compounds.