可乐定硬膜外腔预注的镇静效应和对左旋布比卡因麻醉的影响

Sedation and clinical effects of epidural clonidine pretreatment on epidural anesthesia with levobupivacaine

目的观察不同剂量可乐定硬膜外腔预注对经腹全子宫切除手术患者的镇静效应和对左旋布比卡因硬膜外麻醉效果的影响。方法30例ASAI～II级经腹全子宫切除手术患者,根据硬膜外腔预注可乐定剂量的不同随机分为3组:C0组(n=10)为生理盐水对照组,C2组(n=10)2μg/kg,C4组(n=10)4μg/kg。腰2～3椎间隙穿刺、置管,可乐定注射15min后以0.5%左旋布比卡因行硬膜外阻滞。结果可乐定给药5～15min后,脑电双频指数明显降低,C4组降低比C2组更显著;警觉/镇静评分为C4组<C2组<C0组(P<0.05或0.01)。C0组1例需要辅助镇静药物。各组麻醉效果良好,阻滞上界平面T6(T3～T6),3组左旋布比卡因用量、术中补液速度、MAP和HR变化幅度相似。平均痛觉阻滞维持时间:与C0组(26±2.1)min相比,C2组(36±0.7)min延长,C4组(43±2.6)min最长(P<0.01～0.05)。C0组使用阿托品和麻黄素患者比率(13.3%和6.7%)较低(P<0.05)。结论硬膜外腔可乐定预注具有剂量相关的镇静效应,延长左旋布比卡因麻醉作用时间,但可引起循环系统抑制。

[Objective] To investigate sedation and clinical effects of epidural clonidine pretreatment on epidural anesthesia with levobupivacaine. [Methods] Thirty ASA Ⅰ-Ⅱ gynecologic patients were randomly assigned into three groups with epidural clonidine either 0, or 2, or 4 μg/kg （group C0, C2, C4）. There were ten patients in each group. All epidural anesthesia were performed at the L2-3 interspaces with 0.5% levobupivacaine after epidural single shot clonidine. [Results] The bispectral index droped significantly after clonidine injection 5-15 mins in group C2 and group C4 （P 〈0.05 or 0.01）. The scores of OAA/S droped in group C2 compare with C0, especially significantly in group C4. One case in control group need additional intraoperative sedation. All anesthesia were clinically satisfied with average blockade T6 （T3-6）. The dose of levobupivacaine were similar among groups. The average duration of pain-free after the first shot of levobupicaine is shortest in control group, and longest in group C4 （P 〈0.05 or 0.01）. The frequency of atropine and ephedrine used was lower in control group （P 〈0.05）. [Conclusion] Epidural single shot clonidine can induce dose-related sedative effects and bispectral index decreases, but may inhibit hemodynamics.