右美托咪定与咪达唑仑在局部麻醉下眼部美容术中镇静效果的比较

Comparison of sedative effects of Dexmedetomidine and Midazolam on ocular cosmesis under local anesthesia

目的通过观察右美托咪定与眯达唑仑在局部麻醉下眼部美容手术中的镇静效果，评价其在整形美容术中应用的可行性与安全性。方法将120例眼部美容者随机分成4组（n=30）。在术前10min，A组静脉泵注右美托咪定0．5μg；B组静脉泵注咪达唑仑0．02mg／kg；C组静脉泵注咪达唑仑0．05me,／kg；D组空白对照。注药后对动脉血氧饱和度（SpO2）、呼吸频率（RR）、心率（HR）、平均动脉压（MAP）、镇静水平（Ramsay镇静分级）进行监测与评定至术终。结果自给药结束即刻起30min内，与B组相比，A组、C组镇静效果显著（P〈0．05），其两组镇静效果的差异，无显著的统计学意义（P〉0．05）；手术结束即刻，A组的镇静效果优于C组（P〈0．05）；给药即刻起至术终，c组呼吸抑制的发生率明显高于A、B、D3组，其差异有统计学意义（P〈0．05）；各组心动过缓和低血压的发生率差异，无显著的统计学意义（P〉0．05）。结论与高剂量咪达唑仑（0．05mg／kg）相比，术前静脉泵注小剂量右美托咪定（0．5μg/kg）可在局部麻醉下眼部美容术中达到相似的镇静效果，且镇静效果更加持久，同时对呼吸系统无明显的抑制作用，安全有效，值得临床推广应用。

Objective To evaluate the feasibility and safety of the applications of Midazolam and Dexmedetomidine in the cosmetic surgery through the observation of their sedative effects on ocular cosmesis under local anesthesia. Methods A hundred and twenty patients who would receive ocular cosmesis under local anesthesia were randomly divided into four groups （ n = 30） ： patients in the Group A were treated with 0.5 μg/kg Dexmedetomidine; those in the Group B administrated with 0.02 mg/kg Midazolam （lower dosage） ;those in the Group C were used with 0.05 mg/kg Midazolam （higher dosage） ; Patients in the Group D were as the controls. Drugs were infused over a 10-minute period with venous pump. The arterial oxygen saturation （SpO2 ）, respiratory frequency （RR）, heart rate （HR）, mean arterial pressure （MAP） and the level of sedation （Ramsay sedation grading） were recorded and evaluated to the end of surgery. Results In the first 30 minutes from the end of infusion, compared with group B, group A and group C showed marked sedation （ P 〈 0.05 ）, but no significant difference was found between them （ P 〉 0.05） ; At the right end of the surgery, the sedative effect of Group A was better than that of Group C （ P 〈 0.05） ; From the infusion of drugs to the end of the surgery, higher incidence of respiratory depression （SpO2〈 90% or respiratory rate 〈 8 beats/min） was observed in Group C than in Group A, B and D （ P 〈0.05 ）, but there is no difference in the incidence of bradycardia （HR 〈 50 bpm） and hypotension （ MAP 〈 60 mmHg） in all the 4 groups （ P 〉 0.05 ）. Conclusion Compared with high dose of Midazolam （0.05 mg/kg） , preoperative intravenous infusion of small dose of Dexmedetomidine （0.5 μg/kg） can aehieved a similar sedative effect in the eye eosmesis under local anesthesia, and the sedative effect is more dura- ble, without causing significant inhibitory effect on the respiratory system. We suggest that dexmedetomidine is both safe and effective,and it worths to be popularized.