Wheeler Peggy, Hoffman William E, Baughman Verna L, Koenig Heidi
Anesthesiology Department, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
J Neurosurg Anesthesiol. 2005 Apr;17(2):86-90. doi: 10.1097/01.ana.0000151408.62650.b5.
Frontal electromyography (FEMG) may increase during painful stimulation and indicate patient arousal. The Datex-Ohmeda Entropy Module calculates state entropy (SE) of the electroencephalogram (EEG; 0.8-32 Hz) and response entropy (RE) of EEG and FEMG (0.8-47 Hz). We determined whether RE increases above SE (RE--SE), an indication of FEMG, increase during painful stimuli and if this is related to paralysis or level of anesthesia. With the unanesthetized baseline measurement, SE was 89 +/- 2 and RE was 98 +/- 2. During paralysis and anesthesia with either 0.8% (n = 10) or 1.4% (n = 10) isoflurane, SE decreased to 63 +/- 7 and 34 +/- 14, respectively, and the RE--SE difference decreased 90%. Before recovery from paralysis, arterial catheter or head pin placement increased RE--SE above unanesthetized levels in eight patients (five treated with 0.8% and three with 1.4% isoflurane), consistent with an increase in FEMG. The elevated RE--SE difference was related to a significant increase in SE, blood pressure, and heart rate. After recovery from paralysis, tetanic stimulation of the ulnar nerve increased the RE--SE difference above unanesthetized levels in 8 of 20 patients (6 treated with 0.8% and 2 with 1.4% isoflurane). In these patients, SE increased significantly. The remaining 12 patients did not show an increase in RE--SE during tetanic stimulation and SE did not increase. We conclude that increased RE during painful stimulation was not dependent on recovery from paralysis but was seen more often in patients anesthetized with 0.8% compared with 1.4% isoflurane. This suggests that RE reflects FEMG and may be useful to identify inadequate anesthesia and patient arousal during painful stimuli.
前额肌电图（FEMG）在疼痛刺激期间可能会增强，并提示患者觉醒。Datex-Ohmeda熵模块可计算脑电图（EEG；0.8 - 32Hz）的状态熵（SE）以及EEG和FEMG（0.8 - 47Hz）的反应熵（RE）。我们确定了在疼痛刺激期间RE是否高于SE（RE - SE）（这表明FEMG增强），以及这是否与麻痹或麻醉深度有关。在未麻醉的基线测量中，SE为89±2，RE为98±2。在使用0.8%（n = 10）或1.4%（n = 10）异氟烷进行麻痹和麻醉期间，SE分别降至63±7和34±14，并且RE - SE差值降低了90%。在从麻痹状态恢复之前，动脉导管置入或头部固定针的放置使8例患者（5例使用0.8%异氟烷治疗，3例使用1.4%异氟烷治疗）的RE - SE高于未麻醉水平，这与FEMG增强一致。升高的RE - SE差值与SE、血压和心率的显著增加有关。从麻痹状态恢复后，对尺神经进行强直刺激使20例患者中的8例（6例使用0.8%异氟烷治疗，2例使用1.4%异氟烷治疗）的RE - SE差值高于未麻醉水平。在这些患者中，SE显著增加。其余12例患者在强直刺激期间未显示RE - SE增加，且SE也未增加。我们得出结论，疼痛刺激期间RE增加并不依赖于从麻痹状态恢复，与使用1.4%异氟烷麻醉的患者相比，在使用0.8%异氟烷麻醉的患者中更常见。这表明RE反映了FEMG，并且可能有助于识别疼痛刺激期间麻醉不足和患者觉醒的情况。
