静脉注射右美托咪啶和咪唑安定对蛛网膜下隙阻滞麻醉效果的影响

Effects of intravenous dexmedetomidine and midazolam in patients undergoing spinal anesthesia

目的比较静脉注射右美托咪啶和咪唑安定对蛛网膜下隙阻滞麻醉效果的影响。方法选择择期在蛛网膜下隙阻滞麻醉下行经尿道前列腺电切术患者90例(ASAⅠ-Ⅱ级),随机分为3组:对照组(C组)、右美托咪啶组(D组)和咪唑安定(M组),每组30例。D组患者预先静脉泵注右美托咪啶0.5μg/kg,M组患者预先静脉泵注咪唑安定0.05 mg/kg,C组则给予等容生理盐水10 ml。各组患者行蛛网膜下隙阻滞,均给予0.5%罗哌卡因2 ml。比较各组患者一般情况;Ramsay镇静评分、感觉阻滞平面、感觉及运动阻滞恢复时间;术中低血压、心动过缓发生例数;术后首次要求使用镇痛药的时间及各组术后24 h要求使用镇痛药物的例数。结果三组患者一般情况无明显差异;与C组比较,D组和M组镇静效果满意(P<0.05),而发生低血压、心动过缓副作用无明显差异(P>0.05);与M组比较,D组患者最高感觉阻滞平面明显增高(P<0.05),感觉阻滞恢复时间及术后首次要求使用镇痛药物的时间明显延长(P<0.05),术后24 h要求使用镇痛药物的病例明显减少(P<0.05)。结论蛛网膜下隙阻滞前单次剂量静脉注射右美托咪啶0.5μg/kg和咪唑安定0.05 mg/kg均能产生良好的镇静效果;而相比咪唑安定,右美托咪啶能明显延长罗哌卡因引起的感觉阻滞时间,并具有较好的镇痛效果。

Objective To investigate the effects of intravenous dexmedetomidine and midazolam in patients undergoing spinal anesthesia.Methods Ninety patients （ASA Ⅰ-Ⅱ） undergoing transurethral resection of the prostate under spinal anesthesia were randomly divided into three groups：control group（C group）,dexmedetomidire group（D group） and midazolam group （M group）.Patients received intravenous dexmedetomidine 0.5 μg/kg and midazolam 0.05 mg/kg in D group and M group,respectively,while patients received intravenously the same volume of normal saline in D group.Then all patients underwent spinal anesthesia using 0.5％ ropivacaine 2 ml.The sedation,side effects （hypotension and bradycardia）,maximum upper level of sensory blockade,recovery time of sensory and motor blockade were recorded.Postoperative analgesic requirements were also recorded.Results The general condition of patients were similar among three groups.Compared with control group,the sedation scores in D group and M group were significantly increased （P ＜ 0.05）.Compared with M group,patients in D group showed similar sedation and side effects （P ＞ 0.05）,while the maximum upper level of sensory blockade and recovery time of sensory blockade were increased （P ＜ 0.05）,the time to first analgesia request increased,and the patients who required for analgesia decreased within 24 h after operation （P ＜ 0.05）.Conclusion Intravenous dexmedetomidine 0.5 μg/kg and midazolam 0.05 mg/kg both provide good sedation,while dexmedetomidine could have better effects than midazolam to increase spinal ropivacaine sensory blockade and decrease additional analgesia.