膈肌增厚率联合浅快呼吸指数预测撤机结果的价值

The value of phrenic thickening rate combined with shallow fast respiratory index in predicting the results of weaning

目的比较超声检测右侧膈肌增厚率(DTF)结合浅快呼吸指数(RSBI)与单独RSBI在机械通气患者中预测撤机结局的价值.方法选取需机械通气患者46例,进行自主呼吸试验(SBT)1h,记录RSBI,采用超声测量并计算右侧DTF.分析撤机成功组与撤机失败组各指标间的差异.绘制ROC曲线比较各指标对撤机结局的预测价值.结果撤机成功组34例,撤机失败组12例.撤机成功组RSBI明显低于撤机失败组(P<0.05),而DTF则明显高于撤机失败组(P<0.05).RSBI、DTF预测撤机成功的ROC曲线下面积(AUC)分别为0.82、0.88.以DTF≥26%、RSBI≤105次/(L·min)为截点,其预测撤机成功灵敏度分别为94.1%、94.1%,特异度分别为66.7%、41.7%.结合DTF≥26%和RSBI≤105次/(L·min),可使得预测撤机成功的特异度提升至83.3%,同时伴有灵敏度轻度下降至88.2%.结论超声检测DTF是预测机械通气患者撤机成功的有效指标.而与单独RSBI相比,右侧DTF联合RSBI能更准确的预测撤机结局.

Objective To compare the value of index of right diaphragmatic thickening fraction(DTF)combined with rapid shallow breathing index(RSBI)and rapid shallow breathing index in predicting the outcome of weaning in patients with mechanical ventilation.Methods 46 patients with mechanical ventilation admitted to the Department of ICU,Zhejiang Cancer Hospital were enrolled.The spontaneous breathing test(SBT)was performed for 1 hour.The RSBI was recorded.The DTF was calculated by ultrasound.The differences of indexes were analyzed between weaning success group and the weaning failure group.The ROC curve was plotted to compare the predictive value of each index to the outcome of the weaning.Results Among 46 patients,there were 12 patients failing the weaning attempt.The RSBI in success group was significantly lower than that in failure group(P<0.05),while the DTF was significantly higher than that in failure group(P<0.05).The area under the ROC curve(AUC)for RSBI and DTF predictions of successful weaning were 0.82 and 0.88,respectively.With DTF≥26%,RSBI≤105 breaths/(L·min)as the cut-off point of DTF and RSBI,the sensitivity were 94.1%and 94.1%,and the specificity were 66.7%and 41.7%,respectively.Combined with DTF≥26%and RSBI≤105breaths/(L·min),the specificity can be increased to 83.3%,accompanied by a slight decrease in sensitivity to 88.2%.Conclusion DTF is an effective indicator for predicting outcome of the weaning in patients with mechanical ventilation.Compared with RSBI alone,the index of right DTF combined with RSBI can more accurately predict the outcome of the weaning.