Spinal Anesthesia with 0.75% Isobaric Ropivacaine for Lower Extremity Operation

Kim, Su Jin; Kim, Mi Woon

Abstract

BACKGROUND: Ropivacaine closely resembles bupivacaine with propyl group substitutes for butyl group at the same position. Ropivacaine is presented as 100% S-isomer with important implication of safety and less cardiotoxic than bupivacaine. Because of this, ropivacaine is used as an epidural anesthesia. However this study was performed to evaluate clinical effects of ropivacaine for spinal anesthesia.
METHODS
Thirty patients (ASA I-II) scheduled for elective lower extremity operation were randomly selected and received spinal anesthesia with 3 ml of 0.75% isobaric ropivacaine. The patients were placed in the lateral position and dura puncture was performed at the L3-4 interspace using the median or paramedian approach with a 25 G Quincke spinal needle. After spinal anesthesia, sensory block was assessed using the pin-prick test every 2 min., motor block was assessed using a four-point scale, and circulatory variables were monitored every 5 min.
RESULTS
The mean sensory block level was T 8.6 and the maximum sensory block level was T4. Time needed for extremity motor block was 10.8 min. and 25 of 30 patients reached Bromage scale 3. Duration of motor and sensory block were 260.6 min. and 422.3 min. Hemodynamic changes (arterial pressure and pulse) were stable during anesthesia and complications were rare.
CONCLUSIONS
We concluded that 0.75% isobaric ropivacaine was suitable for spinal anesthesia with good lower extremity sensory and motor block, and it was long-lasting without any specific complications.