老年病人术中脑电双频指数与七氟烷浓度关系的研究

目的研究老年病人静吸复合麻醉时，七氟烷浓度与脑电双频指数（BIS）及年龄之间的关系。方法将普外科上腹部手术病人30例（ASA分级Ⅱ～Ⅲ），按年龄分为两组：A组为60～69岁；B组为70～79岁，每组15例。采用七氟烷与瑞芬太尼静吸复合麻醉，调节七氟烷浓度使BIS值在50～60。记录术中各时间段吸气末和呼气末七氟烷浓度及BIS值，并记录睁眼时间（从停止吸入麻醉药至病人睁眼时间）、拔管时间、麻醉恢复时间（从停止吸入麻醉药至恢复定向力的时间），对两组病人的年龄与呼气末七氟烷浓度及BIS值之间进行回归分析。结果两组病人各项生命体征平稳，年龄与呼气末七氟烷浓度具有显著的相关性。两组病人两个时间点（手术开始30min与60min）的呼气末七氟烷浓度与BIS值之间的相关系数均〉0．60，大部分具有显著相关性。两组患者睁眼时间、拔管时间、麻醉恢复时间差异无统计学意义，两组患者术后随访均无术中知晓。结论老年病人年龄与七氟烷浓度及BIS值之间具有显著的相关性，临床麻醉中要根据病人的年龄选择合适的七氟烷浓度，同时BIS值可以作为调节七氟烷麻醉深度的一个重要参考指标。

Correlation between bispectral index and sevoflurane concentration in elderly patients undergoing upper-abdominal surgery

Objective To investigate the correlation between sevoflurane concentration and bispectral index （BIS） during remifentanil-sevoflurane anesthesia in elderly patients. Methods Thirty ASA class Ⅱ～Ⅲ patients aged over 60 year undergoing upper-abdominal surgery were randomized to one of two groups： the first group（60- 69 year） and the second group（70-79 year）. Sevoflurane was titrated to keep BIS values between 50-60 during operation. The BIS values before and during anesthesia and at extubation, sevoflurane concentration, eye opening time, extubation time, recovery time of anesthesia were recorded and compared between the two groups. Results No statistical differences were found in eye opening time, extubation time and recovery time of anesthesia between two groups. There was a positive correlation between BIS values and the age. A positive correlation exists between the values of BIS and sevoflurane concentration during surgery. Conclusion A positive correlation exists among BIS, age and sevoflurane concentration in elderly patients. To choose safe sevoflurane concentration according to the age to keep BIS values between 50-60 in elderly patients is necessary.