超声监测膈肌厚度吸气变化率对机械通气患者拔管结局评价

目的 评估超声检测膈肌增厚率对预测机械通气（MV）患者拔管结局的价值。方法 选取重症医学科（ICU）行MV>48 h且准备拔管的54例患者，于自主呼吸试验（SBT）期间以床旁超声测量并计算膈肌增厚率（DTF）和膈肌增厚浅快呼吸指数（DTF-RSBI），同时记录浅快呼吸指数（RSBI）及其他生理指标。采用ROC曲线评价DTF和DTF-RSBI预测拔管成败的价值。结果 36例拔管成功（成功组），18例失败（失败组），成功组患者DTF明显高于失败组，RBSI及DTF-RBSI明显低于失败组（P均<0.05）。取28.50%为截断值，DTF预测拔管的AUC为0.702，敏感度和特异度分别为78.80%和61.10%；DTF-RBSI取72.6次/（min·mm）为截断值，预测拔管的AUC为0.903，敏感度和特异度分别为100.00%和72.20%。结论 DTF-RSBI预测拔管结果比DTF及传统RSBI更准确，具有较高实用价值。

Ultrasound monitoring of diaphragm thickness fraction in evaluating extubation outcome in patients undergoing mechanical ventilation

Objective To observe the predictive value of diaphragmatic ultrasound for extubation outcomes in patients undergoing mechanical ventilation(MV). Methods Totally 54 patients were ventilated mechanically more than 48 hours and ready to extubate when admitted to ICU were enrolled. During the T-tube spontaneous breathing trial (SBT), the diaphragm thickening fraction (DTF) and diaphragm thickening rapid shallow breathing index (DTF-RSBI) were measured and calculated using bedside ultrasound. Rapid shallow breathing index (RSBI) and other physiological indexes were recorded. ROC curve was used to evaluate the predictive value of DTF and DTF-RSBI for extubation. Results There were 36 patients underwent successful (successful group) and 18 underwent failed extubation (failure group). DTF in successful group was significantly higher than that in failure group, while RBSI and DTF-RBSI in successful group were significantly lower than those in failure group (both P<0.05). Taken 28.50% as the cut-off value of DTF, the AUC for DTF was 0.702, and the sensitivity and specificity was 78.80% and 61.10%, respectively. When the cut-off value of DTF-RSBI was 72.6 breaths/(min·mm), AUC for DTF-RSBI was 0.903, the sensitivity and specificity was 100% and 72.20%, respectively. Conclusion DTF-RSBI is more accurate than DTF and traditional RSBI, having better practical value for predicting extubation outcomes.