右美托咪定和咪达唑仑在蛛网膜下隙与硬膜外联合阻滞中应用的比较

A comparison of dexmedetomidine and midazolam in patients during combined spinal and epidural anesthesia

目的比较静脉注射右美托咪定和咪达唑仑对蛛网膜下隙与硬膜外联合阻滞（CSEA）的镇静、呼吸和循环等临床作用的影响。方法择期在CSEA下行下肢骨折内固定术患者90例，按照随机数字表法分为右美托咪定组、咪达唑仑组和对照组，每组30例。在L3-4行CSEA操作，麻醉平面固定在R后，三组分别静脉注射右美托咪定、咪达唑仑或0．9％氯化钠。记录麻醉前（T0）、麻醉平面固定后（T1）及给药10、15、30、45、60rain（T2-T6）的Ramsay评分、平均动脉压（MAP）、心率、呼气末二氧化碳分压（PzrCO：）、呼吸频率及术中知晓情况。结果右美托咪定组和咪达唑仑组T2-T6时Ramsay评分高于本组T0、T1时和同期对照组，MAP低于本组T0、T1时和同期对照组，差异有统计学意义（P〈0．05）；右美托咪定组T2-T6时心率低于同期咪达唑仑组和对照组，差异有统计学意义（P〈0．05）；咪达唑仑组T2-T6时PETCO2高于同期右美托咪定组和对照组，差异有统计学意义（P〈O．05），呼吸频率低于同期右美托咪定组和对照组，差异有统计学意义（P〈0．05）。右美托咪定组和咪达唑仑组术中知晓率低于对照组[16．7％（5，30）和13．3％（4／30）比93．3％（28/30）]，差异有统计学意义（P〈O．05）。结论右美托咪定、咪达唑仑能提供良好的镇静效果，减少术中知晓，轻度抑制血压。右美托咪定抑制心率，对呼吸没有影响，而咪达唑仑抑制呼吸。

Objective To compare the influence for intravenous dexmedetomidine and midazolam during combined spinal and epidural anesthesia （CSEA） on sedation, respiratory and circulatory. Methods Ninety patients with lower extremity fractures and internal fixation,were divided into dexmedetomidine group, midazolam group and control group by random digits table with 30 cases each. CSEA was performed at L3-4 interspace. After block reached Ts level, dexmedetomidine, midazolam and 0.9% sodium chloride were given to the three groups. Ramsay score,mean arterial pressure （MAP）,heart rate （HR）,partial pressure of carbon dioxide in end expiratory gas （PnCO2）, respiratory rate （RR） were recorded before anesthesia （T0）, after CSEA （T1）, and 10,15,30,45,60 min after giving drug （T2 -T6）, and intraoperative awareness was recorded. Results Ramsay score in dexmedetomidine group and midazolam group at T2 - T6 were higher than those in the group T0, T1 and concurrent control group （P 〈 0.05 ）, MAP were lower than those in the group T0,T1 and concurrent control group （P 〈 0.05）. HR in dexmedetomidine group at T1-T6 were lower than those in concurrent midazolam group and control group （P 〈 0.05）. PETCO2 in midazolam group at T2 - T6 were higher than those in concorrent dexmedetomidine group and control group （P 〈 0.05）, RR were lower than those in concurrent dexmedetomidine group and control group （P 〈 0.05）. The rate of intraoperativeawareness in dexmedetomidine group and midazolam group was lower than that in control group [ 16.7% （5/30） and 13.3% （4/30） vs. 93.3% （28/30）,P 〈 0.05 ]. Conclusions Dexmedetomidine and midazolam provide good sedation to reduce intraoperative awareness, slight inhibition of blood pressure. Dexmedetomidine can decrease HR, but it does not influenee respiratory function. Midazolam restrains respiratory function.