异丙酚复合芬太尼对患者拇短展肌运动诱发电位的影响

Effects of propofol combined with fentanyl on motor evoked potentials of abductor pollicis brevis

目的探讨异丙酚复合芬太尼对患者拇短展肌运动诱发电位（MEP）的影响。方法择期普通外科手术患者11例，ASAⅠ或Ⅱ级，年龄26～48岁。以第6颈椎棘突为刺激线圈的中点进行磁刺激，周期20s。试验Ⅰ：经30s匀速静脉注射异丙酚2mg／kg。记录给药即刻至患者出现睁眼或体动反应期间右拇短展肌MEP波幅的基础值、最低值和最后值，及其对应的潜伏期，以及波幅下降至最低值的时间（时程）。试验Ⅱ：试验Ⅰ结束后30min，经大隐静脉依次匀速注射异丙酚2mg／kg和芬太尼5μg／kg，每种药物注射时间为30s。记录给药即刻开始拇短展肌MEP波幅的基础值、最低值和最后值，及其对应的潜伏期，以及时程，记录时间为360s。结果与基础值比较，两试验拇短展肌MEP波幅的最低值和最后值降低（P〈0．01）；与试验Ⅰ比较，试验Ⅱ拇短展肌MEP波幅的最后值降低（P〈0．05）。结论与静脉注射异丙酚比较，异丙酚复合芬太尼对患者拇短展肌MEP的抑制作用更强。

Objective To investigate the effects of propofol given alone or in combination with fentanyl on motor evoked potentials （MEPs） of abductor pollicis brevis. Methods Eleven ASA Ⅰ or Ⅱ patientsaged 26-48 yr weighing 45-69 kg scheduled for elective surgery were enrolled in this study. The patients were unpremedicated. Magnetic stimuli were delivered to the 6th cervical vertebra and the MEPs of abductor pollicis brevis were recorded. Test Ⅰ ： propofol 2 mg/kg was injected iv over 30 seconds and the MEPs were recorded from the very beginning of propofol injection till the patients regained consciousness. Test Ⅱ was performed at 30 min after prepofol injection in test Ⅰ. Propofol 2 mg/kg was injected iv over 30 seconds as in test I followed by fentanyl 5 μg/kg injected iv over 30 seconds. MEPs were recorded every 20 seconds in both tests. The recording time was 360 seconds. Results The lowest and last values of MEP amplitude were significantly lower in both tests than the baseline value （ P 〈 0.01 ）. The last value of MEP amplitude was significantly lower in test Ⅱ than in test Ⅰ （ P 〈 0.05 ）. Conclusion The inhibitory effect of propofol combined with fentanyl on MEP is stronger than that of pmpofol given alone.