Rappaport M, Ruiz Portillo S, Ortiz D, Fountain S S, Kula T A
University of California Brain Function Study Unit, Agnews Developmental Center, San Jose.
Spine (Phila Pa 1976). 1994 Jul 1;19(13):1525-9. doi: 10.1097/00007632-199407000-00020.
This study analyzed systematic changes in stimulus intensity and duration on the latencies and amplitudes of somatosensory-evoked potential peaks obtained upon posterior tibial nerve stimulation of orthopedic patients under anesthesia.
To examine the effects of systematic stimulus changes on somatosensory-evoked potential patterns and to compare the sensitivity of different peaks.
Previous studies primarily examined the effects of either stimulus intensity or stimulus duration but not their interactions.
Nine orthopedic patients were tested using three stimulus intensities and three stimulus durations. Five peak latencies and four amplitudes were measured. Data consisted of frequency of peak occurrences under each condition and analyses of variances of peak latencies and amplitudes.
Three latencies yielded stable findings (P40, N50, P60). Peak latencies under anesthesia were not affected by stimulus intensity or duration. Amplitudes, however, were affected differentially. P40-N50 increased with increases in stimulus intensity or stimulus duration, but no significant interaction effects were found. N50-P60 showed no significant changes associated with stimulus intensity or duration.
Under combined isoflurane/nitrous oxide anesthesia, somatosensory-evoked potential patterns obtained upon stimulation of the posterior tibial nerves showed no significant changes in major peak latencies with changes in stimulus intensity or duration. However, changes in amplitude were found. Stimulus intensity-duration interaction effects were observed, described, and interpreted.
本研究分析了麻醉状态下骨科患者胫后神经刺激时，刺激强度和持续时间的系统性变化对体感诱发电位峰潜伏期和波幅的影响。
研究刺激的系统性变化对体感诱发电位模式的影响，并比较不同波峰的敏感性。
既往研究主要关注刺激强度或刺激持续时间的影响，而非二者的相互作用。
对9名骨科患者采用三种刺激强度和三种刺激持续时间进行测试。测量了5个峰潜伏期和4个波幅。数据包括每种条件下峰出现的频率以及峰潜伏期和波幅的方差分析。
三个潜伏期结果稳定（P40、N50、P60）。麻醉状态下的峰潜伏期不受刺激强度或持续时间的影响。然而，波幅受到不同影响。P40-N50随刺激强度或刺激持续时间的增加而增加，但未发现显著的交互作用。N50-P60与刺激强度或持续时间无关，无显著变化。
在异氟烷/氧化亚氮复合麻醉下，刺激胫后神经获得的体感诱发电位模式显示，主要峰潜伏期随刺激强度或持续时间的变化无显著改变。然而，发现了波幅的变化。观察、描述并解释了刺激强度-持续时间的交互作用。
