title: [Comparative study between 0.5% bupivacaine, 0.5% enantiomeric mixture of bupivacaine (S75-R25) and 0.75% ropivacaine, all associated to fentanyl, for epidural cesarean section anesthesia.].
abstract: OBJECTIVE
  Clinical trials with local anesthetic levo-enantiomers have shown higher safety due to lower cardiotoxicity. This study aimed at evaluating quality of anesthesia and maternal/fetal repercussions of 0.5% bupivacaine, enantiomeric 0.5% bupivacaine (S75-R25) and 0.75% ropivacaine, all associated to fentanyl, in epidural cesarean section anesthesia.
  
  
  METHODS
  Participated in this study 90 full-term pregnant women, physical status ASA I, submitted to elective cesarean section under epidural anesthesia, who were divided into tree groups: group I - 23 ml racemic 0.5% bupivacaine with epinephrine; Group II -23 ml enantiomeric 0.5% bupivacaine (S75-R25) with epinephrine; Group III - 23 ml of 0.75% ropivacaine. Fentanyl (2 ml) was associated to local anesthetics in all groups. The following parameters were evaluated: onset, analgesia duration, sensory and motor block degree, time to hysterotomy and delivery, quality of muscle relaxation and anesthesia, maternal hemodynamic and respiratory changes, newborn vitality (evaluated through Apgar score and cord-blood gases analysis), and side-effects.
  
  
  RESULTS
  There were no differences among groups, except for anesthesia quality. In groups with predominant levo-enantiomer fraction were clinically worse with the need for anesthetic complementation in three cases. Analgesia duration was longer in the ropivacaine group.
  
  
  CONCLUSIONS
  Enantiomeric mixture 0.5% bupivacaine (S75-R25) and 0.75% ropivacaine for epidural anesthesia have provided as good conditions as racemic 0.5% bupivacaine for the surgical act. Newborn repercussions have shown that all solutions were equally safe.
authors.affiliation: CET, SBA.
authors.forename: Carlos Alberto Figueiredo
authors.initials: CA
authors.lastname: Côrtes
authors.forename: Amaury Sanchez
authors.initials: AS
authors.lastname: Oliveira
authors.forename: Luis Fernando Lima
authors.initials: LF
authors.lastname: Castro
authors.forename: Franz Schubert
authors.initials: FS
authors.lastname: Cavalcanti
authors.forename: Maurício Marsaioli
authors.initials: MM
authors.lastname: Serafim
authors.forename: César
authors.initials: C
authors.lastname: Taia
authors.forename: Siguero
authors.initials: S
authors.lastname: Taia Filho