韩氏(HANS)仪对七氟醚最低肺泡浓度(MAC)的影响

HAN'S ACUPOINT NERVE STIMULATOR(HANS) REDUCES THE MAC OF SEVOFLURANE

目的：将ＨＡＮＳ仪用于心血管手术的临床麻醉，观察其能否减少麻醉药的用量。方法：４０例５～１０岁先天性心脏病室间隔缺损（ＶＳＤ）、房间隔缺损（ＡＳＤ）患儿，随机分为Ⅰ组（单用七氟醚组）和Ⅱ组（ＨＡＮＳ加七氟醚复合组）。用体动反应上下交叉点（ｕｐａｎｄｄｏｗｎ）法分别测定两组的最低肺泡气浓度（ＭＡＣ）。结果：Ⅰ组即单用七氟醚组的ＭＡＣ值为２．７２±０．０７Ｖｏｌ％；而Ⅱ组即七氟醚加ＨＡＮＳ组的ＭＡＣ值为２．２４±０．１５Ｖｏｌ％，比空白组减少了１７．４％。两组间Ｐ值＜０．００１，有非常显著的区别。切皮的刺激使Ⅰ组的心率增加了３８．０％，收缩压增加了２３．０％，舒张压增加了３４．０％；而Ⅱ组即七氟醚加ＨＡＮＳ组心率增加了１６．０％，收缩压增加了１４．３％，舒张压增加了１３．７％。结论：ＨＡＮＳ可减少七氟醚的ＭＡＣ值１７．３８％，具有非常显著的统计学意义。在１ＭＡＣ左右，机体接受同样伤害性刺激时，ＨＡＮＳ具有一定的心血管稳定作用。

Aims: HANS (Han's Acupoint Nerve Stimulator) is known to accelerate the release of β endorphin, enkephalins and dynorphins in the central nerves system, hence to produce a marked analgesic effect in humans. The purpose of this study was to determine the effects of HANS on the MAC (minimal alveolar concentration) of sevoflurane in cardiovascular operations.Methods: 40 children diagnosed as VSD or ASD were randomly allocated to two groups. Group Ⅰ (n=20)received sevoflurane alone, group Ⅱ(n=20)received sevoflurane plus HANS. MAC determination, in response to the stimulus of skin incision, was made using the“up and down”method. Results: The MAC of group Ⅰ was 2.72±0.07%, and that of group Ⅱ was 2.24±0.15%. In response to the stimulation of skin incision, the HR, SBP, DBP of group Ⅰ increased 38.0%, 23.0% and 34.0%, as compared to 16.0%, 14.3%, 13.7% in group Ⅱ, respectively. The difference between the two groups was very significant ( P<0.001). The results suggested that HANS can significantly reduce the MAC of sevoflurane by 17.4% and also stabilize the cardiovascular response to noxious stimulation.