【摘要】 目的观察右美托咪定(Dex)对七氟醚吸入诱导喉罩插入时应激反应及脑电双频指数(BIS)的影响。方法择期全麻患者60例,年龄20~60岁,ASAⅠ或Ⅱ级,随机均分为D1组、D2组和C组,分别于麻醉诱导前15 min静脉输注Dex 0.5、1.0μg/kg和生理盐水,均以七氟醚复合琥珀胆碱1.0 mg/kg麻醉诱导。记录输注Dex前即刻(T0)、输注后5 min(T1)、喉罩插入前即刻(T2)、喉罩插入后1 min(T3)、3 min(T4)、5 min(T5)时的BIS、MAP、HR,并于T0、T1、T2和T5时抽取静脉血2.5 ml检测血糖(BG)和血浆皮质醇(Cor)浓度。结果 T1时D1和D2组HR、BIS和Cor较T0时降低,BG升高(P<0.05),D2组较D1组更显著(P<0.05);诱导过程中D2组心动过缓的发生率高于C组和D1组。喉罩插入后,C组MAP、HR、BIS、Cor和BG均显著升高(P<0.01);D1组Cor升高,D2组Cor降低(P<0.05),D1和D2组MAP和HR均升高(P<0.05),BIS和BG未见明显变化。除BG外,D1和D2组各指标均低于C组,D2组更显著(P<0.05)。结论 Dex 0.5、1.0μg/kg均可降低BIS,产生明显镇静效应,抑制七氟醚吸入诱导喉罩插入时的应激反应;Dex 1.0μg/kg的作用更加理想,但要注意防止围麻醉期出现的严重心动过缓。更多还原

【Abstract】 Objective To evaluate the effects of two single preanesthetic doses of dexmedetomidine(0.5 μg/kg and 1.0 μg/kg)on bispectral index(BIS) and stress reaction undergoing laryngeal mask insertion under anesthetic induction with sevoflurane.Methods Sixty ASA Ⅰ or Ⅱ patients,aged 20 to 60 years,undergoing elective surgery under general anesthesia were randomly divided into three groups to receive 0.5 μg/kg and 1.0 μg/kg dexmedetomidine(group D1 and D2,n=20) or saline solution(group C,n=20) infusion for at least 15 minutes before anesthetic induction with sevoflurane in oxygen by face mask.After laryngeal mask insertion,anesthesia was maintained with 2% sevoflurane.Heart rate(HR),mean arterial pressure(MAP) and bispectral index(BIS)were recorded at the time before dexmedetomidine infusion(T0),5 minutes after loading dose(T1),just before insertion(T2),and 1,3,5 minutes(T3-T5)after insertion.Venous blood samples were taken to measure the plasma cortisol concentrations(Cor) and blood glucoses(BG) at corresponding time points.Results Demographic data of the patients in three groups were comparable.In group D1 and group D2,HR,BIS and Cor decreased,but BG increased compared with basic value after dexmedetomidine loading dose was given(P<0.05).After laryngeal mask insertion,in group C,MAP,HR,Cor,BG and BIS values increased significantly(P<0.01);in group D1 and group D2,MAP and HR increased(P<0.05),however,the change in BG and BIS values was not statistically significant;Cor increased in group D1but decreased in group D2(P<0.05).MAP,HR,Cor and BIS values were significantly lower but BG was higher in group D1 and group D2 than group C after insertion(P<0.05).Conclusion Both Dexmedetomidine 0.5 μg/kg and 1.0 μg/kg caused sedation and significantly decreased haemodynamics and stress reaction to laryngeal mask insertion during sevoflurane anesthesia induction.Dexmedetomidine 1.0 μg/kg was better than Dexmedetomidine 0.5 μg/kg.Severe bradycardia during anesthesia should be noticed.更多还原