Department of Physiology, Assistance Publique-Hôpitaux de Paris, Raymond-Poincaré Hospital, INSERM U 1179, University of Versailles Saint-Quentin en Yvelines, Garches, Paris, France; General Intensive Care Unit, Assistance Publique-Hôpitaux de Paris, Raymond-Poincaré Hospital, INSERM U1173, University of Versailles Saint-Quentin en Yvelines, Garches, France.
Department of Neurology, Neuro-ICU, Columbia University, New York, NY, USA.
Br J Anaesth. 2018 Dec;121(6):1290-1297. doi: 10.1016/j.bja.2018.06.029. Epub 2018 Sep 4.
Mismatch negativity (MMN) is the neurophysiological correlate of cognitive integration of novel stimuli. Although MMN is a well-established predictor of awakening in non-sedated comatose patients, its prognostic value in deeply sedated critically ill patients remains unknown. The aim of this prospective, observational pilot study was to investigate the prognostic value of MMN for subsequent awakening in deeply sedated critically ill patients.
MMN was recorded in 43 deeply sedated critically ill patients on Day 3 of ICU admission using a classical 'odd-ball' paradigm that delivers rare deviant sounds in a train of frequent standard sounds. Individual visual analyses and a group level analysis of recordings were performed. MMN amplitudes were then analysed according to the neurological status (awake vs not awake) at Day 28.
Median (inter-quartile range) Richmond Assessment Sedation Scale (RASS) at the time of recording was -5 (range, from -5 to -4.5). Visual detection of MMN revealed a poor inter-rater agreement [kappa=0.17, 95% confidence interval (0.07-0.26)]. On Day 28, 30 (70%) patients had regained consciousness while 13 (30%) had not. Quantitative group level analysis revealed a significantly greater MMN amplitude for patients who awakened compared with those who had not [mean (standard deviation) = -0.65 (1.4) vs 0.08 (0.17) μV, respectively; P=0.003).
MMN can be observed in deeply sedated critically ill patients and could help predict subsequent awakening. However, visual analysis alone is unreliable and should be systematically completed with individual level statistics.
失匹配负波（MMN）是对新刺激进行认知整合的神经生理相关物。尽管 MMN 是预测非镇静昏迷患者觉醒的可靠指标，但它在深度镇静危重患者中的预后价值尚不清楚。本前瞻性观察性初步研究旨在探讨 MMN 对深度镇静危重患者后续觉醒的预后价值。
在 ICU 入院第 3 天，使用经典的“odd-ball”范式在一系列频繁的标准声音中给予罕见的偏差声音，对 43 名深度镇静的危重患者进行 MMN 记录。对记录进行个体视觉分析和组水平分析。然后根据第 28 天的神经状态（清醒与未清醒）分析 MMN 幅度。
记录时的中位数（四分位距）Richmond 评估镇静量表（RASS）为-5（范围，从-5 到-4.5）。MMN 的视觉检测显示出较差的观察者间一致性[kappa=0.17，95%置信区间（0.07-0.26）]。在第 28 天，30 名（70%）患者已恢复意识，而 13 名（30%）患者未恢复。定量组水平分析显示，与未觉醒的患者相比，觉醒的患者的 MMN 幅度明显更大[平均值（标准差）=-0.65（1.4）与 0.08（0.17）μV，分别；P=0.003）]。
MMN 可在深度镇静的危重患者中观察到，可能有助于预测随后的觉醒。然而，单独的视觉分析不可靠，应系统地结合个体水平的统计数据完成。
