Long-latency auditory evoked potentials (LLAEPs) may help further advances in understanding consciousness under general anesthesia and promote more objective means of assessing sedation depth than conventional clinical signs. Among the LLAEP components, the auditory N1 shows promise as a measure of sedation depth and a marker of consciousness, but findings are so far inconclusive. Research with animals can help elucidate the effects of various anesthetics on the N1 and other LLAEPs, but investigations of LLAEPs under anesthesia in animals is lacking. To address this deficit, we examined the P1, N1, P2, and N2, along with their corresponding peak-to-peak complexes, in 10 Wistar rats anesthetized with 1.5–2 % isoflurane in pure oxygen and again after recovery. While under anesthesia, subdermal needle electrodes were inserted and secured for electroencephalographic (EEG) recordings. LLAEPs were assessed during a 20-min, passive, two-tone (500 ms inter-tone interval) paradigm with randomized short (1 s) and long (5 s) inter-pair intervals (IPIs). Overall, while the LLAEP peaks under isoflurane were less defined, they were not eliminated. The peak-to-peak amplitudes, particularly the P1-N1, were significantly smaller under isoflurane than during post-recovery. Our preliminary findings indicate that isoflurane produces global suppression across LLAEP components, presumably reflecting impaired integration of top-down and bottom-up attention and sensory systems under profound sedation with isoflurane.

长潜伏期听觉诱发电位 (LLAEP) 可能有助于进一步了解全身麻醉下的意识，并促进比常规临床体征更客观的评估镇静深度的方法。在 LLAEP 组成部分中，听觉 N1 显示出作为镇静深度的量度和意识标记的前景，但迄今为止的发现尚无定论。动物研究有助于阐明各种麻醉剂对 N1 和其他 LLAEP 的影响，但缺乏对动物麻醉下 LLAEP 的研究。为了解决这一缺陷，我们在 10 只 Wistar 大鼠中检测了 P1、N1、P2 和 N2 及其相应的峰-峰复合物，这些大鼠用纯氧中的 1.5-2% 异氟醚麻醉，并在恢复后再次检查。在麻醉状态下，皮下针电极被插入并固定用于脑电图 (EEG) 记录。在 20 分钟、被动、双音（500 毫秒音间间隔）范例中评估 LLAEP，其中随机短（1 秒）和长（5 秒）对间间隔 (IPI)。总的来说，虽然异氟醚下的 LLAEP 峰不太明确，但它们并没有被消除。异氟醚下的峰峰值幅度，尤其是 P1-N1，明显小于恢复后的幅度。我们的初步研究结果表明，异氟醚对 LLAEP 成分产生整体抑制，这可能反映了在异氟醚深度镇静下自上而下和自下而上的注意力和感觉系统的整合受损。具有随机短（1 秒）和长（5 秒）对间间隔 (IPI) 的双音（500 毫秒音间间隔）范例。总的来说，虽然异氟醚下的 LLAEP 峰不太明确，但它们并没有被消除。异氟醚下的峰峰值幅度，尤其是 P1-N1，明显小于恢复后的幅度。我们的初步研究结果表明，异氟醚对 LLAEP 成分产生整体抑制，这可能反映了在异氟醚深度镇静下自上而下和自下而上的注意力和感觉系统的整合受损。具有随机短（1 秒）和长（5 秒）对间间隔 (IPI) 的双音（500 毫秒音间间隔）范例。总的来说，虽然异氟醚下的 LLAEP 峰不太明确，但它们并没有被消除。异氟醚下的峰峰值幅度，尤其是 P1-N1，明显小于恢复后的幅度。我们的初步研究结果表明，异氟醚对 LLAEP 成分产生整体抑制，这可能反映了在异氟醚深度镇静下自上而下和自下而上的注意力和感觉系统的整合受损。