年龄对妇科手术七氟醚麻醉清醒肺泡浓度的影响

Influence of age on the MAC-awake of sevoflurane in women undergoing gynecological surgeries

目的观察年龄对妇科手术七氟醚麻醉清醒肺泡浓度（MAC-awake）的影响。方法择期行妇科短小手术患者60例，ASAⅠ或Ⅱ级，依据年龄均分为三组：Ⅰ组，20～29岁；Ⅱ组，30～39岁；Ⅲ组，40～50岁。8％七氟醚诱导，眼睑反射消失后维持呼气末七氟醚浓度3％10min后插入喉罩，术中七氟醚浓度维持在3％。手术结束后以0．1％浓度梯度按Dixon序贯法调整七氟醚浓度并拔出喉罩。计算意识恢复时呼气末七氟醚的MAC-awake即EC50及相应的95％可信区间（CI）。结果Ⅰ、Ⅱ、Ⅲ组意识恢复时呼气末七氟醚EC50及相应的95％C1分别为0．64％（0．57％～0．70％）、0．55％（0．50％～O．60％）及0．44％（0．37％～0．50％）。结论妇科手术七氟醚麻醉随着年龄增长其七氟醚的MAC-awake逐渐下降。

Objective To observe the influence of age on the MAC-awake of sevoflurane in women undergoing gynecological surgeries. Methods Sixty patients with ASA Ⅰ or Ⅱ undergoing gynecological surgeries under sevofluence were divided into three groups with 20 each： group Ⅰ , 20- 29 years old; group Ⅱ, 30-39 years old; and group Ⅲ, 40-50 years old. Anesthesia was induced with sevoflurane 8% in oxygen, the end-tidal sevoflurane concentration was maintained at 3% for 10 min after loss the eyelash reflex and then the LMA was inserted, and the intraoperative maintenance concentration of Sevoflurane was 3%. At the end of the surgeries, the concentration of sevoflurane was determined with the up-down sequence method at a 0.1% interval, and then the LMA was extubated. The MAC-awake of sevoflurane and corresponding 95% confidence intervals （95% CI） were calculated. Results The MAC-awake and corresponding 95% CI of the three groups were as follows： group Ⅰ, 0.64% （0. 57%-0. 70%）; group Ⅲ , 0. 55% （0.50%-0.60%）; and group Ⅲ, 0.44% （0.37%-0.50%）. Conclusion The MAC-awake of sevoflurane in women undergoing gynecological surgeries decrease with the increase of age.