评估被动抬腿试验（PLR）对呼吸机脱机结局的预测能力。

以关键词"被动抬腿试验"、"机械通气"、"脱机"在中国知网、维普网、百度学术、中国临床试验注册中心搜索文献及相关临床研究，以关键词"passive leg raising or raise"、"mechanical ventilation or ventilator"、"weaning"在PubMed、Embase、the Cochrane Library、clinicaltrials.gov上搜索文献及相关临床研究；搜索日期为建库至2018年2月11日。文献搜索和数据提取由两人独立进行，所获文献采用诊断准确性研究的质量评价工具（QUADAS-2）评估其研究质量，相关数据则使用RevMan 5.3.5和Meta-disc软件进行分析。

最终有3篇文献被纳入，其中中文1篇，英文2篇，均具有较高的质量评分。患者总数为145人，共进行228例次PLR和脱机试验。其中，PLR阳性123例次，脱机成功87例次，失败36例次；PLR阴性105例次，脱机成功18例次，失败87例次。PLR预测脱机的正确率为76%。PLR阳性预测脱机成功的敏感度为0.83（95%CI：0.74~0.90），特异度为0.71（95%CI：0.62~0.79）；汇总受试者操作特征曲线（SROC）曲线下面积为0.82±0.04，约登指数为0.54。

被动抬腿试验能用于预测呼吸机脱机结局。

To evaluate the predictive value of passive leg raising test in mechanical ventilation weaning.

Clinical trials in the field of using passive leg raising test in mechanical ventilation weaning were retrieved from China national knowledge internet (CNKI), CQVIP, Baidu Scholar, chictr.org.cn, PubMed, Embase, the Cochrane Library, clinicaltrials.gov until February 11, 2018. Data were independently extracted by two reviewers. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) were used to evaluate the quality of these studies, and Review Manager 5.3.5 and Meta-disc were used to conduct the analysis.

Three studies were included in the analysis, one of which was in Chinese and the other two were in English. Moreover, these studies were assessed as moderate to high quality studies. There were 145 patients altogether and 228 PLR tests and spontaneous breath trials (SBTs) were conducted. There were 123 positive PLR tests and 87 with successful SBTs. While there were 105 negative PLR tests and 18 with successful SBTs. The predictive accurate rate of PLR in mechanical ventilation weaning was 76.3%. The pooled sensitivity and specificity with positive PLR test to predict a successful SBT were 0.83 (95% CI: 0.74-0.90) and 0.71 (95% CI: 0.62-0.79), respectively; Youden index was 0.54 and the area under summary receiver operating characteristic curve (SROC) was 0.82±0.04.

PLR test can be used to predict mechanical ventilation weaning.