熵指数与RASS评分在机械通气危重患者镇静中的相关性研究

Correlation between entropy index and RASS score in sedation in critically ill patients with mechanical ventilation

目的:研究熵指数(entropy index)与RASS评分在有创机械通气危重患者中的相关性。方法:选取2017-12—2018-12期间入住重症监护病房予标准镇静方案镇静的有创机械通气患者68例,根据RASS评分结果判断镇静水平,调整镇静治疗的用药剂量,以达到适度镇静目标(RASS评分-2～0)。监测记录患者的无创动脉平均压(MBP)、心率(HR)、呼吸(R)、脉搏氧饱和度(SpO_2)、反应熵(RE)、状态熵(SE)、RASS评分,连续监测24 h。以RASS评分≥1分及RASS评分≤-3分别绘制受试者工作特征曲线(ROC曲线),确定镇静适度时熵值的最佳截断值。结果:随着镇静深度的加深,熵指数的监测值逐渐减小,镇静不同等级时熵值的变化差异有统计学意义(P<0.01),而患者的生命体征(MBP、HR、R、SpO_2)均维持在较稳定水平,差异无统计学意义(P>0.05);RE、SE、RE-SE与RASS评分的相关系数分别为0.923、0.914、0.741(P<0.01),RE与RASS评分相关性最高,适度镇静时患者的RE值为70(56～84),SE值为60(49～71);诊断镇静不足的最佳RE/SE截断值为84/75、镇静过度的最佳RE/SE截断值为54/47。结论:熵指数与RASS评分有良好的相关性,可用于有创机械通气患者镇静深度的判断,指导镇静治疗方案的调整。

Objective:Study the correlation between entropy index and RASS in critically ill patients with invasive mechanical ventilation.Method:A total of 68 patients with invasive mechanical ventilation who received sedation with standard sedation scheme during the period from December 2017 to December 2018 were enrolled.The sedation level was determined according to the RASS score,and the dosage of sedative treatment was adjusted to achieve moderate sedation target(RASS score-2 to 0).The noninvasive arterial mean blood pressure(MBP),heart rate(HR),respiration(R),pulse oxygen saturation(SpO2),reaction entropy(RE),state entropy(SE)and RASS scores were recorded and monitored continuously for 24 hours.The receiver operating characteristic curve was drawn with RASS score≥1 and RASS score≤-3,respectively to determine the best cut off value of entropy value in moderate sedation.Result:With the deepening of monitoring the depth of sedation,entropy index value decreased gradually,there were significant differences among these changes of RE,SE and RE-SE in different sedation grades(P<0.01).But the vital signs(MBP,HR,R,SpO2)of the patients could be maintained at a relatively stable level,there were no significant differences(P>0.05);the correlation coefficient of RE,SE,RE-SE and RASS score were 0.923,0.914,0.741(P<0.01),the correlation between RE and RASS score was the highest;the values of RE,SE and RE-SE in moderate sedation were 70(56~84)and 60(49~71);the best RE/SE cut-off value for diagnosis of Inadequate sedation was 84/75,and the best RE/SE cut-off value for Excessive sedation was 54/47.Conclusion:Entropy index has a good correlation with RASS score,which can be used to judge the sedation depth of invasive mechanical ventilation patients,and to guide the adjustment of sedative treatment programs.