目的 观察右旋美托咪啶对硬膜外麻醉下老年高血压患者的影响。方法 选取重庆市巴南区人民医院2011年1月-2013年7月收治的70例行前列腺汽化切除术的老年原发性高血压患者，随机分成治疗组（n=35）与对照组（n=35），治疗组静脉注射右旋美托咪啶0.4 μg/kg，对照组静脉注射咪唑安定2 mg，两组其他用药完全一致。记录入室时、给药后5 min、麻醉后30 min、2 h患者血压、心率及血氧饱和度，并对两组进行Ramsay镇静评分。结果 对照组给药后5 min，血压及心率较入室时上升明显，治疗组相对波动较小，两组对比差异明显（P<0.05），具有统计学意义。两组血氧饱和度变化比较基本一致，没有明显差异。治疗组不良反应发生率约为20%，低于对照组（40%），两组对比差异显著（P<0.05）。结论 小剂量的右旋美托咪啶对老年高血压患者有良好的镇静及中枢降压作用，且不会产生呼吸抑制，维持围术期生命体征稳定。

Objective To observe the effect of Dexmedetomidine on elderly patients with hypertension under epidural anesthesia. Methods From January 2011 to July 2013, 70 elderly patients with essential hypertension, who were operated by vaporization resection of prostate in People's Hospital of Chongqing Banan, were randomly devided into treatment (n= 35) and control groups (n= 35). Patients in the treatment group received Dexmedetomidine 0.4 μg/kg by iv injection, while the patients in the control group received Midazolam 0.2 mg by iv injection. The other drugs were same used in the two groups. Blood pressure (mean aortic pressure, MAP), heart rate (HR), and blood oxygen saturation (SPO₂) at entering the operating room (before operation), 5 min after administration, 30 min, and 2 h after anesthesia were recorded. And Ramsay sedation score of the two groups were counted. Results AT5 min after administration, blood pressure and heart rate of the control group increased significantly compared with the baseline, patients in the treatment group had relatively small fluctuations, the differences were statistical significance (P < 0.05). There was no significant statistical difference in the blood oxygen saturation of the patients in the two groups. The adverse reaction in the treatment group was about 20%, lower than that of the control group (40%), with the significant difference between the two groups (P < 0.05).Conclusion A small dose of Dexmedetomidine has a good effect of sedation and central antihypertensive in elderly patients with hypertension, while has no respiratory depression during anesthesia, which could maintain stable vital signs.