Ellerkmann Richard Klaus, Soehle Martin, Alves Thorsten Michael, Liermann Vidal-Markus, Wenningmann Ingobert, Roepcke Heiko, Kreuer Sascha, Hoeft Andreas, Bruhn Jörgen
Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany.
Anesth Analg. 2006 May;102(5):1456-62. doi: 10.1213/01.ane.0000204289.47792.56.
Recently, Datex-Ohmeda introduced the Entropy Moduletrade mark for measuring depth of anesthesia. Based on the Shannon entropy of the electroencephalogram, state entropy (SE) and response entropy (RE) are computed. We investigated the dose-response relationship of SE and RE during propofol anesthesia in comparison with the Bispectral Indextrade mark (BIS). Twenty patients were studied without surgical stimulus. Anesthesia was induced by a constant propofol infusion of 2000 mg/h (451 +/- 77 microg x min(-1) x kg(-1)) via a large forearm vein. Propofol was infused until substantial burst suppression occurred (more than 50%) or mean arterial blood pressure decreased to <60 mm Hg. Hereafter, infusions were stopped until recovery of BIS values up to 60 was reached. Subsequently, the constant propofol infusion of 2000 mg/h was restarted to increase depth of anesthesia and again decreased (infusion was stopped) within the BIS value range of 40-60. The coefficient of determination (R2) and the prediction probability (P(K)) were calculated to evaluate the performance of SE, RE, and BIS to predict changing propofol effect-site concentrations. R2 values for SE, RE, and BIS of 0.88 +/- 0.08, 0.89 +/- 0.07, and 0.92 +/- 0.06, respectively, were similar. The calculated P(K) values, however, revealed a significant difference between SE and RE compared with BIS, with P(K) = 0.77 +/- 0.09, 0.76 +/- 0.10, and 0.84 +/- 0.06, respectively. BIS seems to show slight advantages in predicting propofol effect-site concentrations compared with SE and RE, as measured by P(K) but not as measured by R2.
最近，Datex-Ohmeda推出了用于测量麻醉深度的熵模块商标。基于脑电图的香农熵，计算得出状态熵（SE）和反应熵（RE）。我们研究了丙泊酚麻醉期间SE和RE的剂量反应关系，并与脑电双频指数商标（BIS）进行比较。对20例患者进行了研究，且无手术刺激。通过前臂大静脉以2000 mg/h（451±77 μg·min⁻¹·kg⁻¹）的恒定速率输注丙泊酚诱导麻醉。持续输注丙泊酚，直至出现显著的爆发抑制（超过50%）或平均动脉血压降至<60 mmHg。此后，停止输注，直至BIS值恢复至60。随后，重新开始以2000 mg/h的恒定速率输注丙泊酚以加深麻醉深度，并在BIS值为40 - 60的范围内再次降低（停止输注）。计算决定系数（R²）和预测概率（P(K)）以评估SE、RE和BIS预测丙泊酚效应室浓度变化的性能。SE、RE和BIS的R²值分别为0.88±0.08、0.89±0.07和0.92±0.06，三者相似。然而，计算得出的P(K)值显示，与BIS相比，SE和RE之间存在显著差异，P(K)值分别为0.77±0.09、0.76±0.10和0.84±0.06。通过P(K)而非R²测量，与SE和RE相比，BIS在预测丙泊酚效应室浓度方面似乎显示出轻微优势。
