不同剂量右美托咪啶抑制气管插管诱发患者心血管反应效应的比较

目的 比较不同剂量右美托咪啶抑制气管插管诱发患者心血管反应的效应.方法 拟在全麻下行择期上腹部手术患者120例,年龄18～60岁,体重45～80 kg,ASA分级Ⅰ或Ⅱ级,随机分为4组(n=30):对照组(C组)、低、中、高剂量右美托咪啶组(M1～3组),分别在麻醉诱导前15 min静脉输注15 ml生理盐水、右美托咪啶0.25、0.50和1.00μg/kg,输注时间15 min.麻醉诱导后,BIS值≤60并维持5 s时行气管插管后机械通气.于输注右美托咪啶前(T0)、气管插管前(T1)、气管插管即刻(T2)、气管插管后1、3、5、10 min(T3～6)时记录BP和HR;颈内静脉采血,测定血浆肾上腺素(E)、去甲肾上腺素(NE)浓度.结果 与T0时比较,T1时M1～3组HR降低、M3组BP升高,T4～6时C组和M1组血浆E和NE浓度升高(P＜0.05);与T1时比较,C组和M1组T2时BP和HR降低,T3～5时BP和HR升高(P＜0.05);T1～6时M3组较M2组BP升高(P＜0.05).结论 静脉输注右美托咪啶剂量达0.5μg/kg时,可显著抑制伤害性刺激诱发的应激反应.

Effects of different doses of dexmedetomidine in inhibition of cardiovascular response to endotracheal intubation

Objective To compare the effects of different doses of dexmedetomidine in inhibition of cardiovascular response to endotracheal intubation. Methods One hundred and twenty ASA Ⅰ or Ⅱ patients, aged 18-60 yr, weighing 45-80 kg, scheduled for upper abdominal surgery, were randomly assigned to one of 4 groups (n = 30 each): control group (group C); low, median and high doses of dexmedetomidine groups (group M1-3) .In group M1-3, 15 min before anesthesia induction, dexmedetomidine 0.25, 0.5 and 1.0 μg/kg were infused over 15 min respectively, while normal saline 15 ml was given instead of dexmedetomidine in group C. After anesthesia induction, tracheal intubation was performed when the BIS value ≤ 60 and it was maintained for 5 s. The patients were mechanically ventilated. BP and HR were recorded before infusion of dexmedetomidine (T0), before intubation (T1), immediately after intubation (T2) and at 1, 3, 5 and 10 min after intubation (T3-6). Venous blood samples were also taken at the same time to measure the plasma concentrations of epinephrine (E) and norepinephrine (NE). Results Compared with T0, HR was significantly decreased at T1 in group M1-3, BP was significantly increased at T1 in group M3, and the plasma concentrations of E and NE were significantly increased at T4-6 in group C and M1(P ＜0.05). BP and HR were significantly lower at T2, while higher at T3-5 in group C and M1than at T1 (P ＜ 0.05). BP at T1-6 was significantly higher in group M3 than in group M2 (P ＜ 0.05). Conclusion When the dose of dexmedetomidine reaches 0.5 μg/kg, it may effectively inhibit the stress reaction to noxious stimulation.