摘要： 目的 评价右美托咪啶在颈动脉内膜切除术中的安全性和有效性，并探讨其脑保护作用机制。方法 40例颈动脉狭窄性病变患者分别于麻醉诱导前静脉输注右美托咪啶0.40 μg/kg（右美托咪啶组）或等量生理盐水（对照组），并记录给药前（T₀）、气管插管前（T₁）、气管插管后1 min（T₂）、显露颈动脉即刻（T₃）、拔除气管插管前（T₄）、拔除气管插管后1 min（T₅）时的平均动脉压和心率、麻醉药物剂量、麻醉恢复情况，以及围麻醉期血清TNF-α和IL-6 表达变化。结果 与T₀ 时相比，右美托咪啶组患者其余各时间点平均动脉压和心率降低（均P < 0.05），术中丙泊酚和瑞芬太尼剂量明显减少（均P < 0.05），意识恢复时间和拔除气管插管时间缩短（均P < 0.05），呛咳、躁动和术后寒战等不良反应轻微（均P < 0.05）。术后两组患者血清TNF-α和IL-6 表达水平均升高（P < 0.05），以对照组显著。结论 颈动脉内膜切除术中应用右美托咪啶联合全身麻醉，围麻醉期可维持更平稳的血流动力学状态，减少麻醉药物剂量，麻醉复苏迅速且平稳，安全性和有效性良好，并可抑制TNF-α和IL-6等炎性因子的释放而发挥脑保护作用。

关键词: 颈动脉狭窄, 颈动脉内膜切除术, 右美托咪啶, 麻醉, 全身, 血流动力学, 肿瘤坏死因子α, 白细胞介素6

Abstract: Objective  To evaluate the safety and efficacy of dexmedetomidine in patients undergoing carotid endarterectomy (CEA), and to explore its mechanism in cerebral protection.  Methods  Forty patients undergoing CEA were divided into 2 groups: dexmedetomidine group (Group D, N = 20) and control group (Group S, N = 20), respectively receiving dexmedetomidine intravenous infusion (0.40 μg/kg) and the same dose of normal saline. Total intravenous anesthesia (TIVA) was applied in both 2 groups. Mean arterial pressure (MAP) and heart rate (HR) of each patient were recorded at T₀ (before administration), T₁ (before tracheal intubation), T₂ (1 min after intubation), T₃ (carotid explosing), T₄ (before extubation) and T₅ (1 min after extubation) respectively. Total amount of propofol and remifentanil, and patients' recovery conditions after anesthesia were also recorded. Tumor necrosis factor-α (TNF- α) and interleukin-6 (IL-6) were measured and compared before and after operation between 2 groups.  Results  In Group D, MAP and HR decreased significantly at T_1-5 compared with T₀ (P < 0.05, for all); in group S, HR and MAP increased at the same condition (P < 0.05, for all). Total amount of propofol and remifentanil in Group D was lower than that in Group S (P < 0.05, for all). And the patients' recovery conditions in Group D after anesthesia was better than that in Group S (P < 0.05, for all). TNF-α and IL-6 increased after anesthesia compared with that before anesthesia in 2 groups, however, it was higher in Group S than in Group D (P < 0.05, for all).  Conclusions  Dexmedetomidine can provide stable hemodynamic condition during anesthesia in patients undergoing CEA, and improve both the outcome of operation and recovery. With good safety and efficacy, it can provide brain protection by reducing the level of TNF-α and IL-6.

Key words: Carotid stenosis, Endarterectomy, carotid, Dexmedetomidine, Anesthesia, general, Hemodynamics, Tumor necrosis factor-alpha, Interleukin-6