利多卡因布比卡因对兔视神经毒性的电镜观察

目的 观察2%利多卡因及0.75%布比卡因二者单独应用及联合应用,对兔视神经的毒性作用.方法 10只正常新西兰兔随机等分为正常对照组、生理盐水组、利多卡因组、布比卡因组和利多卡因＋布比卡因组5个组,每组2只兔（4眼）.正常对照组不作任何处理;生理盐水组、利多卡因组、布比卡因组分别球后注射生理盐水、2%利多卡因或0.75%布比卡因各1 mL,利多卡因＋布比卡因组球后注射2%利多卡因和0.75%布比卡因各1 mL.注射后观察眼部表现并于注射后48 h取出视神经作透射电镜检查.结果 所有兔均未出现注射并发症;2%利多卡因、0.75%布比卡因均能导致兔视神经发生脱髓鞘现象以及轴突水肿,两药联合组最为显著.结论 2%利多卡因及0.75%布比卡因球后注射对兔视神经均具有轻度的毒性作用,且可能具有相加或协同作用.

Optic nerve toxicity following retrobulbar application of 2% lidocaine and 0.75% bupivacaine in rabbits

Objective To investigate the optic nerve toxicity following retrobulbar application of 2% lidocaine and 0.75% bupivacaine in rabbits.Methods Ten normal rabbits were averagely and randomly divided into five groups as follows: normal control group,normal saline group,lidocaine group,bupivacaine group,lidocaine united with bupivacaine group,each consisting two rabbits(four eyes).No operation was applied to normal control group,but we injected retrobulbarly 1.0 ml normal saline,2% lidocaine and 0.75% bupivacaine into normal saline group,lidocaine group,bupivacaine group,respectively.To lidocaine united with bupivacaine group,we applied retrobulbarly 1.0 milliliter 2% lidocaine and 0.75% bupivacaine,respectively.Performances in eyes were observed at 24h and 48h,and all rabbits were sacrificed for electron microscopy of optic nerve at 48h postoperatively. Results No significant complications were observed.Both 2% lidocaine and 0.75% bupivacaine could demyelinate optic nerve,especially when administered together.Conclusions Not only 2% lidocaine or 0.75% bupivacaine presents toxic effects on optic nerve but they may have synergistic effects.