目的：在麻醉监测管理(monitored anesthesia care，MAC)中，通过与咪唑安定比较，观察右美托咪 定在玻璃体视网膜手术中应用的效果、安全性，探讨其应用可行性。方法：将择期玻璃体视网膜 手术患者40例随机双盲分入咪唑安定组(M组)和右美托咪定组(D组)。每组20例，两组患者均行球 后神经阻滞麻醉，连接脑电双频指数(bispectral index，BIS)监测仪监测并维持BIS值在70~90间， 观察和比较麻醉手术中及复苏期的平均动脉压(mean arterial pressure，MAP)、心率(heart rate， HR)、呼吸频率(respiratory rate，RR)、脉搏氧饱和度(oxygen saturation，SpO2)、Ramsay镇静评 分、疼痛数字评分法(Numerical Rating Scale，NRS疼痛评分)、手术医生和患者麻醉效果评分及不 良反应的差异。结果：与麻醉前比较，手术期D组用药后10 min内的心率、血压下降差异有统计学 意义(P<0.05)，且用药后10 min内D组心率下降幅度较M组更大(P<0.05)。在手术期和复苏期，D组 的NRS疼痛评分均显著低于M组且差异有统计学意义(均P<0.001)，而两组的Ramsay镇静评分差异 无统计学意义(P>0.05)。D组手术期患者的体动发生率和羟考酮使用率显著低于M组(均P<0.05)。 手术医生和患者的麻醉效果评分D组显著高于M组(均P<0.001)。结论：右美托咪定用于玻璃体视 网膜手术，较咪唑安定镇痛效果好且不良反应少，麻醉效果更好。

Objective: The aim of this study was to compare the efficacy and safety of dexmedetomidine versus midazolam for the monitored anesthesia care (MAC) management of patients undergoing vitreoretinal surgery. Methods: Forty patients undergoing selective vitreoretinal surgery were double-blind and randomly dividedinto midazolam group (group M) and dexmedetomidine group (group D), each group had 20 patients. Patients in both groups were anesthetized with posterior bulbous nerve block. Bispectral index (BIS) monitor was connected and the BIS value was maintained between 70 and 90. The mean arterial pressure (MAP), heart rate (HR), respiratory rate (RR), oxygen saturation (SpO2), Ramsay sedation score, numerical rating scale (NRS), surgeon’s and patient’s anesthesia effect score and adverse reactions were recorded during anesthesia and recovery period. Results: Compared with the data of pre-anesthesia, there were statistical differences of the decrease of HR and MAP in group D within the 10 minutes after medication (P<0.05), and the decrease of HR in group D was greater than that in group M (P<0.05). The NRS pain score in group D was significantly lower than that in group M with statistical significance (P<0.001) during the operation and resuscitation, while there was no significant difference in Ramsay sedation score between the two groups during the operation and resuscitation (P>0.05). In terms of adverse reactions to anesthesia, the incidence of spontaneous movement and oxycodone utilization in group D were significantly lower than those in group M (P<0.05). The anesthesia effect scores of surgeons and patients in group D were significantly higher than those in group M (all P<0.001). Conclusion: Dexmedetomidine has better analgesic effect and less adverse reactions than midazolam in vitreoretinal surgery.