Kasaba T, Nonoue T, Yanagidani T, Maeda M, Kosaka Y
Department of Anesthesia, Tottori Prefectural Central Hospital.
Masui. 1990 Nov;39(11):1491-5.
Somatosensory evoked potentials (SSEP) are used increasingly to monitor the integrity of neural pathways in anesthetized patients. To evaluate the influence of epidural anesthesia on the central nervous system, we studied the effects of lumbar or thoracic epidural anesthesia with lidocaine on the median nerve SSEP in 9 patients. The peak latencies (N1, P2, N2) and amplitudes (N1-P2, P2-N2) of the SSEP response over the sensory cortex were recorded before and 15 min after epidural anesthesia. The peak latencies of control and post epidural anesthesia of N1, P1, N2 were 19.2 +/- 1.7 msec, 19.6 +/- 1.6 msec (N1), 24.7 +/- 2.3 msec, 25.7 +/- 2.0 msec (P2), 32.8 +/- 2.8 msec and 34.6 +/- 2.5 msec (N2), respectively. The amplitude of control and post epidural anesthesia of N1-P2, P2-N2 were 4.5 +/- 2.9 microV, 5.9 +/- 6.6 microV (N1-P2), 4.4 +/- 3.2 microV and 5.6 +/- 5.2 microV (P2-N2), respectively. Peak latencies of all components (L1, P2, N2) increased after epidural anesthesia compared with control values. Amplitude of N1-P2 increased significantly following epidural anesthesia compared with control values. The data obtained in this study were contrary to the previous concept that anesthetic agents generally increase the latency of SSEP and decrease their amplitude.
体感诱发电位（SSEP）越来越多地用于监测麻醉患者神经通路的完整性。为评估硬膜外麻醉对中枢神经系统的影响，我们研究了9例患者使用利多卡因进行腰段或胸段硬膜外麻醉对正中神经SSEP的影响。在硬膜外麻醉前及麻醉后15分钟记录感觉皮层上SSEP反应的峰潜伏期（N1、P2、N2）和波幅（N1-P2、P2-N2）。对照及硬膜外麻醉后的N1、P1、N2峰潜伏期分别为19.2±1.7毫秒、19.6±1.6毫秒（N1），24.7±2.3毫秒、25.7±2.0毫秒（P2），32.8±2.8毫秒和34.6±2.5毫秒（N2）。对照及硬膜外麻醉后的N1-P2、P2-N2波幅分别为4.5±2.9微伏、5.9±6.6微伏（N1-P2），4.4±3.2微伏和5.6±5.2微伏（P2-N2）。与对照值相比，硬膜外麻醉后所有成分（L1、P2、N2）的峰潜伏期均增加。与对照值相比，硬膜外麻醉后N1-P2波幅显著增加。本研究获得的数据与之前认为麻醉剂通常会增加SSEP潜伏期并降低其波幅的概念相反。
