右美托咪定对短期记忆影响的临床观察

The clinical effect of dexmedetomidine on short-term memory

目的以咪达唑仑（midazolam，Mid）作对照，观察右美托咪定（dexmedetomidine，Dex）对患者记忆功能的影响。方法选择60例20岁～60岁择期手术患者，美国麻醉医师协会（ASA）分级I～Ⅱ级，按照完全随机方法分为3组，每组20例：Dex组（A组），Mid组（B组），生理盐水组normalsaline，NS，C组）。在麻醉前20min，A组静脉泵注Dex0．7μg／kg持续10min，B组静脉注射Mid0．07mg／kg，C组静脉注射Ns10m1。所有患者在用药前和用药后10min均观看了内容不同的两张水果图片。观察记录用药前和用药后10min患者脑电双频谱指数（bispectralindex，BIS）、警觉，镇静（observer＇sassessmentofalertness／sedation，OAA／S）评分、焦虑视觉模拟／焦虑状态问卷（anxietyvisualanalogue／anxietyquestionnaire，Av刖SAI）评分，术后24h随访患者对用药前后水果图片的记忆情况。结果3组在用药前和用药后10min脉搏血氧饱和度（pulseoxygensaturation，SpO：）无明显变化，A、B组BIS、OAA／S评分、AVA／SAI评分用药前和用药后10rain比较均明显降低（P〈O．05）。术后24h，记起用药前图片者3组均为100％，A组对给药后图片有记忆者为95％，遗忘率5％；而B组对给药后图片有记忆者为0，遗忘率100％，A、B两组给药后遗忘率比较差异有统计学意义（P〈0．01）。A、B组患者对手术麻醉过程未形成不良记忆。结论Dex对短期记忆功能影响小，未产生遗忘作用。

Objective To observe the short-term memory changes after dexmedetomidine （Dex） or midazolam （Mid） intravenous infusion as premedication. Methods Sixty adult patients （ASA I -II ） who would receive the urinary gravel or bladder surgery, or limb bone joint surgery were randomly assigned to three groups with 20 for each as Dex group （Group A） , Mid group （Group B） and normal saline （NS） group （Group C）. In Group A, 0.7 p^g/kg intravenous Dex was maintained for 10 min. In Group B, 0.07-mg/kg Mid was injected. In Group C, 10 ml intravenous NS was given. Every patient watched two different pictures of fruit before and after administration. They were observed for twenty minutes before regional anesthesia. The mean artery pressure, heart rate, pulse oxygen saturation （SpO2）, bispectral index （BIS）, anxiety visual analogue/anxiety questionnaire （AVA/SAI） scale, observer＇s assessment of alertness/sedation （OAA/S） scale were monitored. The above parameters were recorded at the time before （To） and 10 min after administration（T1）. The memory for pictures was noted 24 h postoperation for return visit. Results SpO2 had no differences change before and after administration in both two testing groups, while BIS, OAA/S scale, AVA/SAI scale decreased significantly after administration, which showed an obvious sedative effects of Dex and Mid. All the patients remembered what they had seen in the first picture（T0） （the ratio of recall 100%）. Only one patient forgot the second picture in Group A（the ratio of forgot 5% ）, but in Group B nobody had rememberd about the second picture （the ratio of forgot 100% ）. Conclusions For premedication, Dex and Mid provide good sedation effects. Howeber, Mid could cause anterograde amnesia while Dex has the minimal impact on memory function and amnesia occurrence.