Mantzaridis H, Kenny G N
Department of Anaesthetics, Law Hospital NHS Trust, Lanarkshire, UK.
Anaesthesia. 1997 Nov;52(11):1030-6. doi: 10.1111/j.1365-2044.1997.185-az0327.x.
We describe a novel index derived from the auditory evoked potential, the auditory evoked potential index, and we compare it with latencies and amplitudes related to clinical signs of consciousness and unconsciousness. Eleven patients, scheduled for total knee replacement under spinal anaesthesia, completed the study. The initial mean (SD) value of the auditory evoked potential index was 72.5 (11.2). During the first period of unconsciousness it decreased to 39.6 (6.9) and returned to 66.8 (12.5) when patients regained consciousness. Thereafter, similar values were obtained whenever patients lost and regained consciousness. Latencies and amplitudes changed in a similar fashion. From all parameters studied, Na latencies had the greatest overlap between successive awake and asleep states. The auditory evoked potential index and Nb latencies had no overlap. The consistent changes demonstrated suggest that the auditory evoked potential index could be used as a reliable indicator of potential awareness during propofol anaesthesia instead of latencies and amplitudes.
我们描述了一种源自听觉诱发电位的新型指数——听觉诱发电位指数，并将其与与意识和无意识临床体征相关的潜伏期及波幅进行比较。11例计划在脊髓麻醉下进行全膝关节置换术的患者完成了该研究。听觉诱发电位指数的初始平均（标准差）值为72.5（11.2）。在无意识的第一阶段，该指数降至39.6（6.9），当患者恢复意识时又回升至66.8（12.5）。此后，每当患者失去和恢复意识时，都能获得类似的值。潜伏期和波幅也有类似变化。在所研究的所有参数中，Na潜伏期在连续清醒和睡眠状态之间的重叠最大。听觉诱发电位指数和Nb潜伏期没有重叠。所呈现的一致变化表明，在丙泊酚麻醉期间，听觉诱发电位指数可作为潜在意识的可靠指标，而非潜伏期和波幅。
