撤机参数在机械通气患者呼吸机撤离中的应用价值

Application of multi predictors in the ventilator weaning process

目的 在长时间机械通气患者撤离呼吸机 (简称撤机 )时 ,评价浅快呼吸指数 (RSBI)、气道闭合压 (P0 1)及常规撤机参数的价值。方法 采用前瞻性研究方法 ,对通过自主呼吸试验并满足常规撤机标准的 80例患者 ,检测呼吸运动协调性、痰量、肺部音、咳嗽能力、呼吸频率 (RR)、潮气量(VT)、分钟通气量 (MV)、呼吸系统顺应性 (C)、经皮脉搏容积血氧饱和度 (SpO2 )、动脉血pH值等 10项常规撤机参数及RSBI和P0 1。根据撤机结果分为失败组和成功组。采用单因素 (t检验、χ2 检验 )及多因素Logistic回归进行统计学分析。结果 16例患者撤机失败。单因素分析显示撤机失败组与成功组之间的年龄、RSBI和P0 1差异有显著性 (P <0 0 5 )。以撤机结果为因变量进行Logistic回归分析显示 :仅RSBI和P0 1是回归模型中差异有显著性的两个参数。两组RSBI分别是 (71± 2 3)次·min-1·L-1和 (5 3± 13)次·min-1·L-1(OR =1 0 3) ,P0 1分别是 (7 4± 2 1)cmH2 O和 (3 6± 1 4 )cmH2 O(OR =6 87)。以RSBI≤ 10 5次·min-1·L-1为标准 ,预测撤机成功的敏感性为 90 % ,特异性为 36 % ,准确性为 78%。以P0 1≤ 4 5cmH2 O为标准 ,预测撤机成功的敏感性为 87% ,特异性为 6 6 % ,准确性为 82 %。

Objective To evaluate the effects of rapid shallow breathing index(RSBI),airway occlusion pressure(P 0 1 ) and traditional weaning predictors in the weaning process for patients undergoing prolonged mechanical ventilation Methods Having past 60 min spontaneous breathing trial and satisfied at least 8 of 10 traditional weaning predictors,80 patients fulfilled the criteria of discontinuing ventilation and were included in the study The coordinate capability of breath movement,the quantity of sputum,the quantity of rales in the lungs,the efficiency of coughing,respiratory rate,tidal volume,minute ventilation,compliance of the respiratory system,pulse oxygen saturation,pH value of the arterial blood,RSBI and P 0 1 were determined According to the outcome of weaning from mechanical ventilation,patients were divided into a failure group and a success group T test,chi square test and Logistic regression analysis were used for statistics analysis Results Sixteen (20%) patients failed weaning By univariate analysis,the average age,RSBI and P 0 1 values were significantly different between the failure and the success groups( P <0 05) Logistic regression analysis with weaning outcome as the dependent variable,RSBI[(71±23) breaths·min -1 ·L -1 ,(53±13)breaths·min -1 ·L -1 , OR =1 03] and P 0 1 [(7 4±2 1)cm H 2O,(3 6±1 4)cm H 2O, OR =6 87] were the only significant variables in the model Using RSBI≤105 breaths·min -1 ·L -1 as the threshold value for predicting successful weaning,the sensitivity,specificity and accuracy were 90%,36% and 78% respectively Using P 0 1 ≤4 5 cm H 2O as the threshold value for predicting successful weaning,the sensitivity,specificity and accuracy were 87%,66% and 82% respectively The values of ten traditional predictors,as spirometric and gas exchange,showed no significant difference between the two groups Conclusions In the weaning process for patients undergoing prolonged mechanical ventilation,RSBI and P 0 1 are valuable and accurate predictors Traditional weaning predictors may be useless