Department of Anesthesiology, Affiliated Hospital of North Sichuan Medical College, Nanchong, China.
Department of Anesthesiology, North Sichuan Medical College, Nanchong, China.
Pharmacol Res Perspect. 2023 Aug;11(4):e01116. doi: 10.1002/prp2.1116.
This study was aimed at examining the anesthetic effects and spinal cord injuries in the rats by intrathecal injection of levobupivacaine at different concentrations. Rats with successful intrathecal cannulation were selected and randomly divided into six groups (n = 72), and administered 0.1 mL of 0.125%, 0.25%, 0.5%, or 0.75% levobupivacaine, saline or 5% lidocaine via intrathecal catheters. The potency of levobupivacaine was evaluated by walking behavior. To identify the motor and sensory function, walking behavior and paw withdrawal thresholds (PWTs) were measured once a day. After 7 days, the L4-5 spinal cord segments were removed for histological examination. The onset time of 0.125% levobupivacaine intrathecal injection was 70.0 ± 8.9 s, and the maintenance time was 9.5 ± 1.8 min. The onset time of 0.75% levobupivacaine intrathecal injection was significantly shortened to 31.0 ± 5.5 s, and the maintenance time was significantly extended to 31.3 ± 5.4 min. The severe injury was observed in the 5% lidocaine group, while milder injury was observed in the 0.75% levobupivacaine group. The damage in the 0.5% levobupivacaine group was mild, and there were no histological abnormalities in the 0.125%, 0.25% levobupivacaine and saline groups. The neurotoxicity of intrathecally administered levobupivacaine was concentration dependent. In addition, higher concentrations of levobupivacaine were associated with shorter onset and longer maintenance times. The clinical concentration of levobupivacaine should not exceed 0.5% to avoid potential damage.
本研究旨在通过鞘内注射不同浓度的左旋布比卡因来观察其在大鼠中的麻醉效果和脊髓损伤。选择鞘内置管成功的大鼠，随机分为六组（n=72），通过鞘内导管分别给予 0.1ml 0.125%、0.25%、0.5%或 0.75%左旋布比卡因、生理盐水或 5%利多卡因。通过行走行为评估左旋布比卡因的效能。为了确定运动和感觉功能，每天测量一次行走行为和足趾退缩阈值（PWT）。7 天后，取出 L4-5 脊髓节段进行组织学检查。0.125%左旋布比卡因鞘内注射的起效时间为 70.0±8.9s，维持时间为 9.5±1.8min。0.75%左旋布比卡因鞘内注射的起效时间明显缩短至 31.0±5.5s，维持时间明显延长至 31.3±5.4min。5%利多卡因组观察到严重损伤，0.75%左旋布比卡因组观察到较轻损伤。0.5%左旋布比卡因组损伤较轻，0.125%、0.25%左旋布比卡因和生理盐水组无组织学异常。鞘内给予左旋布比卡因的神经毒性呈浓度依赖性。此外，左旋布比卡因浓度越高，起效时间越短，维持时间越长。临床应用左旋布比卡因的浓度不应超过 0.5%，以避免潜在的损害。
