Estudo comparativo entre bupivacaína racêmica a 0,25% e bupivacaína com excesso enantiomérico de 50% (S75-R25) a 0,25%, associadas ao fentanil para analgesia de parto com deambulação da parturiente

Abstract

Clinical studies with levogyrous enantiomers of local anesthetics have shown better safety due to lower cardiotoxicity. Parturients ambulation during labor may be able to shorten it. This study aimed at comparing anesthetic quality and maternal and fetal repercussions, as well as patients ambulation and spontaneous micturition ability with continuous epidural racemic or 50% enantiomeric excess (S75-R25) 0.25% bupivacaine, associated to fentanyl during labor. Participated in this study 40 parturients, physical status ASA I and II, single fetus and in labor, submitted to continuous epidural analgesia, who were divided in two groups: Group I received 8 mL (20 mg) of 0.25% bupivacaine (S75-R25) and epinephrine, associated to 100 mug fentanyl; and Group II received racemic 0.25% bupivacaine and epinephrine associated to 100 mug fentanyl. The following parameters were evaluated: onset time, sensory block level, motor block level, Rombergs test, ambulation and spontaneous micturition ability, labor and delivery time, maternal hemodynamic and respiratory changes in addition to neonates vitality. There were no statistically significant differences between groups in all evaluated parameters. All parturients presented with muscle strength and ambulation ability and when this was not observed, the reason was Cesarean delivery indication (1 in Group II) or delivery before the time needed to observe such parameter (4 in Group I and 5 in Group II). Both racemic and S75-R25 0.25% bupivacaine associated to fentanyl were effective for labor analgesia.