全麻腰椎后路手术中镇痛/伤害性刺激指数的相关变化

VARIATIONS OF THE ANALGESIA NOCICEPTION INDEX(ANI) DURING GENERAL ANESTHESIA FOR POSTERIOR LUMBAR SURGERY

目的：研究在全麻腰椎后路手术中镇痛/伤害性刺激指数（analgesia nociception index,ANI）的相关变化。方法 ：选取拟行腰椎后路椎板切除减压植骨内固定术的患者,采用丙泊酚及瑞芬太尼靶控输注行麻醉诱导和维持,药物浓度做相应调整以维持脑电双频谱指数在40-60范围,且防止血流动力学剧烈波动,手术结束前30 min,给予舒芬太尼0.15μg.kg^-1。记录并分析特定点（麻醉诱导、切皮、神经根牵拉、静注舒芬太尼）前后收缩压（systolic blood pressure,SBP）、心率（heart rate,HR）和ANI等数据。结果：共30人完成试验,诱导时SBP、HR快速下降同时ANI值显著上升（P〈0.01）;切皮时SBP和HR相对稳定,而ANI值显著下降（P〈0.01）;神经根牵拉时SBP及HR上升,而ANI值进一步下降（P〈0.01）;静注舒芬太尼5 min后,SBP和HR均下降,而ANI值上升（P〈0.01）。切皮前后与神经根牵拉前后的ANI差值相比较差异显著（P〈0.01）。结论：ANI的变化与全麻腰椎后路手术中镇痛与伤害性刺激之间平衡关系的变化相一致,且ANI变化程度可能可以反映不同水平的伤害性刺激。

Objective： The aims of this observational study were to observe the variations of Analgesia Nociception Index（ANI） during general intravenous anesthesia for posterior lumbar surgery. Methods： Adult patients undergoing posterior lumbar laminectomy interbody infusion and internal fixation were enrolled. Propofol and remifentanil were administered using target-controlled devices during anesthesia induction and maintenance. The propofol optimal concentration was adjusted in order to keep bispectral index（BIS） in the 40-60 range, and the optimal concentration of remifentanil was adapted to prevent hemodynamic reactivity（increase or decrease in HR and/or SBP 20% of baseline）. All patients received sufentanil 0.15 μg.kg^-1intravenously 30 min before the expected end of surgery. All data（HR, SBP and ANI values） were recorded and collected at predefined time, including pre-/post induction, pre-/post skin incision, pre-/post Nerve R traction, pre-/post sufentanil bolus. Results： 30 patients completed this observational study, HR and SBP decreased significantly meanwhile ANI increased significantly（P〈0.01） during induction. After incision, ANI decreased（P〈0.01）, while HR and SBP did not change. Nerve root retraction caused a significant increase of HR and SBP, and a notable decreasement of ANI values（P〈0.01）. HR and SBP decreased and ANI increased significantly（P〈0.01） after sufentanil bolus injection. The changes of ANI values during Nerve root retraction was significantly greater than those during skin incision（P〈0.01）. Conclusion： The variation of ANI was in keeping with the evolution of analgesia and nociception balance, and the changes of ANI values may reflect different levels of intraoperative stimulation during general intravenous anesthesia.