缩血管药对全麻复合硬膜外阻滞时脑电双频指数的不同影响

目的 观察七氟醚全麻复合岁哌卡因硬膜外阻滞时使用麻黄素和去氧肾上腺素对脑电双频指数的影响。方法52例ASAⅠ～Ⅱ级全麻复合硬膜外阻滞下行腹部手术的患者，硬膜外穿刺置管（T9～L2）成功后，给予0．5％罗哌卡因5ml，然后以8ml／h持续硬膜外注射，气管插管后以09％七氟醚（呼气未）维持麻醉，以气管插管后10min的心率、平均动脉压和脑电双频指数值为基础值，与麻醉前的血压比较，平均动脉压下降〈30％者分人对照组，下降≥30％者随机分人麻黄素组（0．1mg／kg）或去氧肾上腺素组（2μg／kg）。后二组给予缩血管药物后观察腑电双频指数变化10min，每2min记录一次。若腑电双频指数〉60，则增加七氟醚浓度0．25％，若腩电双频指数〈60则降低匕氟醚浓度0．25％。每隔2．5min测血压和心率、结果 脑电双频指数变化期间麻黄素组的心率明显高于对照组和去氧肾上腺素组，差异有统计学意义（P〈0．05）；与基础值比较，第10分钟时对照组和去氧肾上腺素组腩电双频指数值碌著升高（P〈0．05），但均〈60；第2～10分钟麻黄素组腑电双频指数值均显著升高（P〈0．05）．其中有10个患者的脑电双频指数值〉60，与对照组和去氧肾上腺素组比较差异显著（P〈0．05）；与对照组和去氧肾上腺素组比较，第8分钟和第10分钟时麻黄素组脑电双频指数值显著升高（P〈0．05）。结论 麻黄素使七氟醚全麻复合罗哌卡因硬膜外阻滞时的BIS值升高，而去氧肾上腺素无此作用。

Effect of ephedrine or phenylephrine on bispectral index values during combined general and epidural anesthesia

Objective To research the effect of ephedrine and phenylephrinc on BIS during sevoflurane anesthesia combined with ropivacaine epidural anesthesia. Methods 52 patients（ ASAⅠ - Ⅱ ） undergoing abdominal surgery under total anesthesia （0. 9% sevoflurance） combined epidural block （T9- L2 ）were received an epidural bolus of 0.5% ropivacaine 5ml and maintenance dose 8 ml/h. 10min after intubation, HR, MAP and BIS were recorded as basic value and patients blood pressure was compared with preaneslhesia. Patients whose MAP decreased less than 30% were assigned to control group and those decreased greater than 30% were randu,nl） assigned to ephedrine（0. 1mg/kg） group or phenylephrine（2μg/kg） grnup. After injection of vasoconstriction drug,BIS valae was recorded every 2 rain. Sevofluranece coneentration was increased or decreased with 0.25% according tu BIS value which was more than 60 or less than 60. Bp and FIR. were recorded every 2.5 ,nin. Results HR in ephedrine group was significantly higher than in control group and in phcnylephrine group during BIS value changing（ P〈0. 05 ）. Compared to basie value, BIS value was signifieantly higher at 10 min in control group and in phenylephriue group ahhough less than 60（ P 〈 0. 05 ） and from 2 rain to 10 min in ephedrine group（ P 〈0.05 ）. 10 patients BIS value were higher than 60 in ephedrine group compared in control group and in phcnylcphrine group （ P 〈 0.05 ）. Compared to control group and phenylephrine group,BIS value were significantly higher at 8min and 10 min in ephedrine group （P 〈0. 05）. Conclusion Ephedrine,but not phenylephriue,increases the BIS during sevofluraue anesthesia combined with ropivacaine epidural anesthesia.