Rappaport M, Leonard J, Ruiz Portillo S
University of California Brain Function Study Unit, Agnews Developmental Center, San Jose 95134.
Clin Electroencephalogr. 1992 Jan;23(1):24-30. doi: 10.1177/155005949202300107.
Under anesthesia peak latencies occurring up to 75 milliseconds after stimulus onset upon somatosensory evoked potential testing of the somatosensory evoked potential testing of the posterior tibial nerve were not affected by stimulus intensity (between 5 and 19 ma) or by length of time under isoflurane and nitrous oxide up to over 2 hours. When pre- and postoperative tests on patients who were not under anesthesia were compared with results under anesthesia, no significant latency differences were found in relation to stimulus intensity for peaks N30, P40 and N50. For peaks P60 and N75, however, significantly increased latencies were seen during anesthesia, more pronounced and consistent for N75. Amplitudes, however, were affected by both stimulus intensity and anesthesia duration. A curvilinear relationship was found during early anesthesia. Maximum amplitudes were found at 7 or 11 ma stimulus intensity levels, depending upon which peak was analyzed, with lesser amplitudes occurring at both lower and higher stimulus intensity levels. Stimulus intensity and anesthesia interacted such that maximum amplitude occurred, in general, at 11 ma after short duration anesthesia (6') and at 7 ma after long duration anesthesia (125'). Under long duration anesthesia amplitudes were significantly diminished, mostly at the 11 ma intensity level. At 15 and 19 ma intensity levels peak amplitudes remained relatively constant regardless of anesthesia duration and therefore are the intensities to use to monitor changes during prolonged surgeries. When preoperative during prolonged surgeries. When preoperative and postoperative tests were compared to tests under anesthesia, there was a decrease in amplitude under anesthesia, greater for long than short duration anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)
在麻醉状态下，对胫后神经进行体感诱发电位测试时，刺激开始后长达75毫秒出现的峰值潜伏期不受刺激强度（5至19毫安）或异氟烷和氧化亚氮麻醉时长（长达2小时以上）的影响。将未麻醉患者的术前和术后测试结果与麻醉状态下的结果进行比较时，发现N30、P40和N50峰值在刺激强度方面没有显著的潜伏期差异。然而，对于P60和N75峰值，麻醉期间潜伏期显著增加，N75更为明显且一致。然而，波幅受刺激强度和麻醉持续时间的影响。在麻醉早期发现了一种曲线关系。根据分析的峰值不同，在7或11毫安的刺激强度水平下发现最大波幅，在较低和较高刺激强度水平下波幅较小。刺激强度和麻醉相互作用，一般来说，短时间麻醉（6分钟）后最大波幅出现在11毫安，长时间麻醉（125分钟）后出现在7毫安。在长时间麻醉下，波幅显著减小，主要是在11毫安强度水平。在15和19毫安强度水平下，峰值波幅无论麻醉持续时间如何都保持相对恒定，因此是长时间手术期间用于监测变化的强度。当比较术前和术后测试与麻醉状态下的测试时，麻醉状态下波幅降低，长时间麻醉比短时间麻醉降低得更多。（摘要截短至250字）
