Kurita Tadayoshi, Kawashima Shingo, Khaleelullah Mohamed Mathar Sahib Ibrahim, Nakajima Yoshiki
Department of Anesthesiology and Intensive Care, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, 431-3192, Japan.
J Anesth. 2025 Apr;39(2):198-204. doi: 10.1007/s00540-024-03443-0. Epub 2024 Dec 15.
Intraoperative neurologic monitoring can be useful, but transcranial motor evoked potentials (TcMEPs) are sensitive to anesthetic agents. We compared the effects of anesthetics on the newly developed transesophageal motor evoked potentials (TeMEPs) with those on TcMEPs.
Eleven pigs (25.6 ± 0.8 kg) were anesthetized by desflurane inhalation, remifentanil was maintained at 0.5 µg/kg/min until the end of the experiment. End-tidal desflurane concentration was then maintained at 7, 4, 10, and 13%, and TcMEPs and TeMEPs were measured at each concentration. Desflurane was then discontinued and propofol was infused at 10, 20, 40, and 60 mg/kg/h, and TcMEPs and TeMEPs were measured at each infusion dose. An electroencephalogram monitor was used to measure the hypnotic level.
Both desflurane and propofol anesthesia decreased bispectral index in a dose-dependent manner (P < 0.0001), replicating shallow (or adequate) to deep hypnotic levels in both anesthetic methods. The amplitude of TeMEPs was clearly larger than that of TcMEPs and was significantly larger at all anesthetic depths and all limb sites (P < 0.0001). Amplitudes of the lower extremities were lower than those of the upper extremities (P < 0.0001) for both TcMEPs and TeMEPs, but the amplitudes of TeMEPs were sufficiently large under desflurane as under propofol. The trend of concentration-dependent decrease in the amplitudes of TeMEPs under both anesthetics was not as apparent as in that of TcMEPs.
TeMEPs are more tolerant to anesthesia than TcMEPs and may be a promising MEP monitoring technique for the lower corticospinal tract.
术中神经监测可能有用，但经颅运动诱发电位（TcMEPs）对麻醉药物敏感。我们比较了麻醉药对新开发的经食管运动诱发电位（TeMEPs）和对TcMEPs的影响。
11头猪（25.6±0.8千克）通过吸入地氟醚麻醉，瑞芬太尼维持在0.5微克/千克/分钟直至实验结束。然后将呼气末地氟醚浓度维持在7%、4%、10%和13%，并在每个浓度下测量TcMEPs和TeMEPs。然后停用七氟醚，以10、20、40和60毫克/千克/小时的速度输注丙泊酚，并在每个输注剂量下测量TcMEPs和TeMEPs。使用脑电图监测仪测量催眠水平。
地氟醚和丙泊酚麻醉均以剂量依赖方式降低脑电双频指数（P<0.0001），在两种麻醉方法中均再现了从浅（或适当）到深催眠水平的变化。TeMEPs的波幅明显大于TcMEPs，并且在所有麻醉深度和所有肢体部位均显著更大（P<0.0001）。对于TcMEPs和TeMEPs，下肢的波幅均低于上肢（P<0.0001），但在七氟醚麻醉下TeMEPs的波幅与丙泊酚麻醉下一样足够大。两种麻醉下TeMEPs波幅浓度依赖性降低的趋势不如TcMEPs明显。
TeMEPs比TcMEPs对麻醉更耐受，可能是一种用于监测皮质脊髓束下部的有前途的运动诱发电位监测技术。
