Stasiowski Michał, Duława Anna, Szumera Izabela, Marciniak Radosław, Niewiadomska Ewa, Kaspera Wojciech, Krawczyk Lech, Ładziński Piotr, Grabarek Beniamin Oskar, Jałowiecki Przemysław
Department of Anaesthesiology and Intensive Therapy, Faculty of Medical Sciences in Zabrze, Medical University of Silesia, 40-055 Katowice, Poland.
Department of Anaesthesiology and Intensive Care, Railway District Hospital Katowice, 40-055 Katowice, Poland.
Brain Sci. 2020 Jun 12;10(6):366. doi: 10.3390/brainsci10060366.
Raw electroencephalographic (EEG) signals are rarely used to monitor the depth of volatile induction of general anaesthesia (VIGA) with sevoflurane, even though EEG-based indices may show aberrant values. We aimed to identify whether response (RE) and state entropy (SE) variations reliably reflect the actual depth of general anaesthesia in the presence of different types of epileptiform patterns (EPs) in EEGs during induction of general anaesthesia.
A randomized, prospective clinical study was performed with 60 patients receiving VIGA using sevoflurane with the increasing concentrations (group VIMA) or the vital capacity (group VCRII) technique or an intravenous single dose of propofol (group PROP). Facial electromyography (fEMG), fraction of inspired sevoflurane (FiAA), fraction of expired sevoflurane (FeAA), minimal alveolar concentration (MAC) of sevoflurane, RE and SE, and standard electroencephalographic evaluations were performed in these patients.
In contrast to periodic epileptiform discharges, erroneous SE and RE values in the patients' EEGs were associated with the presence of polyspikes (PS) and rhythmic polyspikes (PSR), which were more likely to indicate toxic depth rather than false emergence from anaesthesia with no changes in the FiAA, FeAA, and MAC of sevoflurane.
Calculated RE and SE values may be misleading during VIGA when EPs are present in patients' EEGs. During VIGA with sevoflurane, we recommend monitoring raw EEG data in scientific studies to correlate it with potentially erroneous RE and SE values and the end-tidal concentration of sevoflurane in everyday clinical practice, when monitoring raw EEG is not available, because they can mislead anaesthesiologists to reduce sevoflurane levels in the ventilation gas and result in unintentional true emergence from anaesthesia. Further studies are required to investigate the behaviour of EEG-based indices during rapid changes in sevoflurane concentrations at different stages of VIGA and the influence of polyspikes and rhythmic polyspikes on the transformation of EEG signals into a digital form.
尽管基于脑电图（EEG）的指标可能显示异常值，但原始脑电图信号很少用于监测七氟烷挥发性吸入麻醉（VIGA）的深度。我们旨在确定在全身麻醉诱导期间脑电图中存在不同类型的癫痫样模式（EP）时，反应（RE）和状态熵（SE）变化是否能可靠反映全身麻醉的实际深度。
对60例接受七氟烷VIGA的患者进行了一项随机、前瞻性临床研究，采用浓度递增（VIMA组）或肺活量（VCRII组）技术，或静脉单次注射丙泊酚（PROP组）。对这些患者进行面部肌电图（fEMG）、吸入七氟烷分数（FiAA）、呼出七氟烷分数（FeAA）、七氟烷的最低肺泡浓度（MAC）、RE和SE以及标准脑电图评估。
与周期性癫痫样放电不同，患者脑电图中错误的SE和RE值与多棘波（PS）和节律性多棘波（PSR）的存在有关，这更可能表明达到了毒性深度，而不是在七氟烷的FiAA、FeAA和MAC无变化的情况下错误地从麻醉中苏醒。
当患者脑电图中存在EP时，在VIGA期间计算得出的RE和SE值可能会产生误导。在七氟烷VIGA期间，我们建议在科学研究中监测原始脑电图数据，以便将其与潜在错误的RE和SE值以及日常临床实践中七氟烷的呼气末浓度相关联；当无法监测原始脑电图时，因为它们可能会误导麻醉医生降低通气气体中的七氟烷水平，导致意外的真正从麻醉中苏醒。需要进一步研究来调查在VIGA不同阶段七氟烷浓度快速变化期间基于脑电图的指标的行为，以及多棘波和节律性多棘波对脑电图信号转换为数字形式的影响。
