ABSTRACT
The aim of this randomized, double blind study was to examine the effect of epidural 0.5% ropivacaine and 0.5% bupivacaine on blood flow velocity waveforms in uteroplacental and fetal arteries with color Doppler ultrasound. Thirty healthy women with singleton, uncomplicated pregnancies were enrolled in the study. The patients were randomly allocated to receive 115-140 mg of either 0.5% ropivacaine [n = 16] or 0.5% bupivacaine [n = 14] in incremental epidural doses. The first ultrasound measurement was performed before injection of the study drug. Pulsatility indices [PI] were derived for the blood flow velocity waveforms of the maternal uterine arteries, the placental arcuate artery, the fetal umbilical and middle cerebral arteries. Ultrasound measurements were repeated five minutes after the injection of local anesthetic and when sensory analgesia reached T6-T4 level. The study concluded that epidural ropivacaine 0.5% for cesarean section did not compromise the maternal or fetal circulation in healthy parturient women. It provided surgical anesthesia that was equally effective as that provided by 0.5% bupivacaine