中潜伏期听觉诱发电位和应激指标对老年人麻醉深度的评估

Evaluation of depth of anaesthesia with midlatency auditory evoked potentials and stress in elderly patients

目的:观察老年人静脉复合麻醉中中潜伏期听觉诱发电位(MLAEP)、血流动力学及血浆皮质醇(CORT)浓度的变化,评估MLAEP和应激指标对老年人麻醉深度的应用价值.方法:择期行上腹部手术的患者40例,年轻组年龄20～45岁,老年组年龄65～81岁,每组20例.ASAⅠ～Ⅱ级,心功能l～2级.无内分泌疾患及听力障碍.常规麻醉诱导后行气管插管并接呼吸机控制通气,于入室后(T0)、麻醉诱导后3min(T1)、插管后1min(T2)、切皮后2min(T3)、关腹后(T4)及拔管后(T5)各时间点分别记录HR,MAP及MLAEP各波波幅及潜伏期.在上述各时间点采中心静脉血3mL,测定血浆皮质醇的浓度.结果:两组患者给药后各时间点的Pa,Nb的潜伏期与基础值比较都延长(P<0.05),Na/Pa,Pa/Nb波幅都降低(P<0.05);在T0时老年组患者Pa较年轻组潜伏期长(P<0.05),两组患者给药后心率与基础值比较均有变化(T2时刻除外),在T5时年轻组心率比老年组快(P<0.05).MAP在给药后T1,T2,T3,T4与基础值比较均降低(P<0.05),在T4时刻年轻组比老年组MAP值高(P<0.05).CORT在给药后各时间点与基础值比较有变化(P<0.05),两组之间比较无统计学意义(P>0.05).结论:MLAEP联合血流动力学及血浆皮质醇可有效地对老年人麻醉深度进行评估.

AIM：To compare the changes of midlatency auditory evoked potentials,hemodynamic and plasma cortisol concentrations in elderly patients during general anaesthesia,in order to evaluate the value of MLAEP and stress in elderly patients of depth of anaesthesia. METHODS：Forty patients scheduled for selective upper abdominal surgery with general anesthesia were randomly divided into 2 groups,one group was the young（aged 20-55 years old）,the other was the old（ages 60-81 years old）,each with 20 cases. They were all ASA Ⅰ - Ⅱ , cardiac functionⅠ - Ⅱ, and no endocrine disorders and hearing impairment. Intubating and ventilating to control breathing machine after induction, HR, MAP, the wave amplitude and latency of MLAEP were recorded when patients entered the operating room （T0） , 3 min after induction of anesthesia （ T1 ） , 1 rain after intubation （T2）, 2 min after skin incision （T3）, after abdominal Commissioner （T4） , and after extubation （ T5 ）. Meanwhile, 3 ml blood samples were abtained from the right internal jugular vein at all time points, and measured plasma＇s CORT concentrations. RESULTS： After administration, two groups of patients＇ incubation period of Pa, Nb were extension, and the volatility of Pa/Na, Pa/Nb were reduced （P 〈0.05 ） ; at T0, the Pa was longer in the old than in the young （ P 〈 0.05 ）. HR was statistical significant differences in 2 groups after administration when compared with previous adminstration（ expect T2） ; at T5, HR was faster in the young than in the old（P 〈0.05）. Map at T1, T2, T3, T4 were slowly compared with previous administration（ P 〈 0.05 ）, and at T4, MAP was higher in the young than in the old （ P 〈 0.05 ）. CORT changed every time compared with previous administration （ P 〈 0.05 ） , but the 2 groups was no statistical significant dirrerences （ P 〉 0. 05 ）. CONCLUSION： MLAEP combined with hemodynamics and plasma cortisol can effectively evaluate the depth of anesthesia in the elderly.