[The predictive value of platelet-to-lymphocyte ratio for weaning failure in septic patients receiving mechanical ventilation].

Objective: To determine the ability of the ratio of platelet to lymphocyte (PLR) for predicting extubation failure in septic patients receiving invasive mechanical ventilation (IMV). Methods: The retrospective cohort study was conducted in ICU at Beijing Chao-Yang Hospital Shijingshan District, Capital Medical University in China from January, 2010 to December, 2019, including patients with sepsis who received IMV. 180 patients were enrolled in the study, including 111 male and 69 female, with the age range of 23-93 years and the median age of 76 years, and with an average age of 71.22 years. The medical records were reviewed, such as age, sex, acute physiology and chronic health evaluation II (APACHEII), sequential organ failure assessment (SOFA), spontaneous breathing trial (SBT) outcome, weaning outcome, complete blood count before SBT. According to weaning outcome, patients were divided into weaning failure and weaning success group. The difference of PLR, white blood cell(WBC), C-reaction protein (CRP) and procalcitonin (PCT) were compared between weaning failure and success group. Receiver-operating characteristics (ROC) curves and multivariate logistical regression analysis were employed to analyze the performance of these inflammatory markers for predicting weaning failure in patients with sepsis. Results: 180 patients with sepsis were included in the study and 37 patients (20.5%) experienced weaning failure (31 SBT failure and 6 extubation failure after successful SBT). PLR was higher in weaning failure group than that in weaning success group (Z=-5.793,P<0.001). Other inflammation biomarkers such as WBC, CRP and PCT were also higher in weaning failure group than that in weaning success group(Z=-4.356, -3.118 and -2.743, P<0.001, 0.002 and 0.006, respectively). According to ROC curves, PLR has a better predictive ability for weaning failure (AUC=0.809,95%CI 0.733-0.885) when compared to WBC (AUC=0.773,95%CI 0.648-0.817), CRP (AUC=0.666,95%CI 0.577-0.755) and PCT (AUC=0.603,95%CI 0.508-0.698). The cutoff value of PLR for predicting weaning failure was 257.69 with sensitivity 78.38%, specificity 76.22%, and diagnostic accuracy 71.66%. According to multivariate logistic regression analyses, PLR>257.69 was an independent risk factor for predicting weaning failure in patients with sepsis. Conclusions: PLR may be a valuable biomarker for predicting weaning failure in septic patients receiving IMV, and the patients with higher PLR should be handled with caution since they are at higher risk of weaning failure, and some more effective treatment should be in consideration after extubation.目的： 探讨血小板与淋巴细胞比值（PLR）对脓毒症患者机械通气撤机结局的预测价值。 方法： 本文是回顾性队列研究，分析2010年1月至2019年12月在首都医科大学附属北京朝阳医院石景山院区呼吸重症监护病房内行机械通气的180例脓毒症患者资料。其中，男性111例、女性69例，年龄范围23~93岁、中位数年龄76岁，平均年龄71.22岁。收集并比较所有患者的一般临床资料包括年龄、性别、急性生理与慢性健康评分（APACHEII）、序贯器官衰竭评分（SOFA）、自主呼吸试验（SBT）结果、撤机结局、SBT前的血常规等，根据撤机结局将患者分为撤机成功组和撤机失败组，比较两组患者的PLR及其他炎症指标如白细胞（WBC）、C-反应蛋白（CRP）、降钙素原（PCT）的差异。应用受试者工作曲线及多因素逻辑回顾分析PLR及其他炎症指标对撤机结局的预测价值。 结果： 纳入的180例患者，其中撤机成功组143例，撤机失败组37例（SBT失败31例，6例拔管失败）。单因素分析提示PLR在撤机失败组明显高于撤机成功组，差异有统计学意义（Z=-5.793，P<0.001），其他炎症指标如WBC、CRP和PCT在撤机失败组也显著高于撤机成功组（Z值分别为-4.356、-3.118和-2.743，P值分别为<0.001、0.002和0.006）。受试者工作曲线提示，PLR预测撤机失败的能力优于WBC、CRP、PCT，其预测撤机失败的曲线下面积分别为（AUC=0.809，95%CI 0.733~0.885）、（AUC=0.773，95%CI 0.648~0.817）、（AUC=0.666，95%CI 0.577~0.755）、（AUC=0.603，95%CI 0.508~0.698）。PLR预测撤机失败的阳性界值为257.69，其敏感度为78.38%，特异度76.22%，诊断正确率71.66%。多因素逻辑回归分析提示PLR>257.69是预测撤机失败的独立预测因子。 结论： 与其他传统炎症生物标记物相比，PLR可能是较好的预测脓毒症患者撤机失败的指标。具有较高PLR的患者则可能撤机失败的风险更高，临床需要更多的有效预防措施。.