Anesthesiology Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA.
J Anesth. 2010 Jun;24(3):394-8. doi: 10.1007/s00540-010-0915-4. Epub 2010 Mar 12.
The clinical sedation scores available for assessing sedation in the intensive care unit (ICU) have drawbacks and limit their usefulness in paralyzed and deeply sedated patients. An objective tool, the bispectral index (BIS), could prove beneficial in such circumstances. We evaluated the ability of BIS to assess the level of sedation and its correlation with the Richmond agitation sedation scale (RASS) in ICU.
Twenty-four, mechanically ventilated, critically ill patients of either sex, 15-65 years of age, were studied over a period of 24 h. They received a standard sedation regimen consisting of a bolus dose of propofol 0.5 mg/kg and fentanyl 1 microg/kg followed by infusions of propofol and fentanyl ranging from 1.5 to 5 mg/kg/h and 0.5 to 2.0 microg/kg/h, respectively. Hemodynamic parameters, temperature, end-tidal carbon dioxide, BIS and RASS values were recorded. The correlation of BIS and RASS was expressed as Kendall correlation coefficients (tau). A p value of <0.05 was considered statistically significant.
A total of 414 readings was obtained. On comparing BIS values for all patients with the corresponding RASS values, there was a statistically highly significant correlation between the two. (tau = 0.56, p < 0.0001). For adequate sedation as judged by a RASS value of 0 to -3, the median BIS value was found to be 56 (range 42-89). A BIS value of 70 had a high sensitivity (85%) and specificity (80%) to differentiate adequate from inadequate sedation.
Our results illustrate that BIS correlates well with RASS when assessing the level of sedation in mechanically ventilated critically ill patients. BIS reliably differentiates inadequate from adequate sedation.
现有的用于评估重症监护病房（ICU）镇静的临床镇静评分存在缺陷，限制了其在瘫痪和深度镇静患者中的应用。一种客观工具，即双频谱指数（BIS），在这种情况下可能会证明是有益的。我们评估了 BIS 评估 ICU 镇静水平的能力及其与 Richmond 躁动镇静评分（RASS）的相关性。
研究了 24 名年龄在 15-65 岁之间的男女机械通气的危重病患者，持续 24 小时。他们接受了标准镇静方案，包括异丙酚 0.5mg/kg 推注和芬太尼 1μg/kg，然后分别输注异丙酚和芬太尼，范围为 1.5-5mg/kg/h 和 0.5-2.0μg/kg/h。记录血流动力学参数、体温、呼气末二氧化碳、BIS 和 RASS 值。BIS 和 RASS 的相关性用 Kendall 相关系数（tau）表示。p 值<0.05 被认为具有统计学意义。
共获得 414 次读数。将所有患者的 BIS 值与相应的 RASS 值进行比较，发现两者之间存在统计学上高度显著的相关性。（tau=0.56，p<0.0001）。对于 RASS 值为 0 至-3 的适当镇静，中位数 BIS 值为 56（范围 42-89）。BIS 值为 70 时，区分适当镇静和不适当镇静的灵敏度（85%）和特异性（80%）较高。
我们的结果表明，BIS 在评估机械通气危重病患者的镇静水平时与 RASS 相关性良好。BIS 可可靠地区分适当镇静和不适当镇静。
