Department of Anesthesiology and Pediatric Clinical Pharmacology Laboratory, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Indian J Pharmacol. 2012 Jan;44(1):41-5. doi: 10.4103/0253-7613.91865.
The plasma-effect site equilibration rate constant (ke0) of propofol was determined with peak bispectral index (BIS) time (T(PEAK)) in our previous study. The present study has been conducted to evaluate the ke0's performance with effect site-controlled infusion algorithm.
Forty unpremedicated patients were randomized to group TE1 (Schnider's pharmacokinetic model with ke0 adapted to T(PEAK) = 74s) and TE2 (T(PEAK) = 96s). In stage 1, all patients received propofol with effect-site concentration (Ce) controlled infusion. Once the pump had injected the mass of propofol necessary to achieve pre-set Ce and while the infusion was stopped, target was reset at 0 μg/ml. When BIS returned to 80 or above, then, in stage 2, the patients received plasma concentration controlled infusion for 10 min. The time of loss of responsiveness (LOR) and BIS were recorded. The differences of Ce at the time of LOR, lowest BIS between stages 1 and 2, hysteresis loop were used to evaluate the performance of ke0.
In both groups, the calculated propofol Ce at the time of LOR in stages 1 and 2 differed significantly (P<0.01); the mean lowest BIS in stage 1 were significantly higher than those in stage 2 (P < 0.05).The relations of propofol Ce versus BIS revealed the apparent hysteresis loop.
The study cannot clinically validate the accuracy of application of ke0 derived from the T(PEAK) = 74 s of BIS with Schnider propofol pharmacokinetic model.
在我们之前的研究中，使用峰双频谱指数（BIS）时间（T（PEAK））确定了丙泊酚的血浆-效应部位平衡速率常数（ke0）。本研究旨在评估 ke0 在效应部位控制输注算法中的性能。
40 例未接受预处理的患者随机分为 TE1 组（Schnider 药代动力学模型，ke0 适应 T（PEAK）= 74s）和 TE2 组（T（PEAK）= 96s）。在第 1 阶段，所有患者均接受丙泊酚效应部位浓度（Ce）控制输注。一旦泵注入达到预设 Ce 所需的丙泊酚质量，且输注停止时，目标重置为 0μg/ml。当 BIS 恢复到 80 或以上时，然后在第 2 阶段，患者接受 10 分钟的血浆浓度控制输注。记录意识消失（LOR）和 BIS 的时间。用于评估 ke0 性能的参数包括 LOR 时的 Ce 差异、第 1 阶段和第 2 阶段之间的最低 BIS 差异和滞后环。
在两组中，第 1 阶段和第 2 阶段 LOR 时的计算丙泊酚 Ce 差异有统计学意义（P<0.01）；第 1 阶段的平均最低 BIS 明显高于第 2 阶段（P<0.05）。丙泊酚 Ce 与 BIS 的关系揭示了明显的滞后环。
该研究不能临床验证 Schnider 丙泊酚药代动力学模型中 T（PEAK）= 74s 的 BIS 衍生的 ke0 应用的准确性。
