D-乳酸跨肺梯度在肺炎诊断及疗效评估中的意义

The role of D-lactate gradient across the lung in the diagnosis and therapeutic evaluation of pneumonia

目的探讨D-乳酸跨肺梯度在快速诊断肺炎及疗效评估中的作用。方法选择入住重症监护病房(ICU)患者为研究对象,患者分肺炎组(n=46)及非肺炎组(n=28),比较两组患者在治疗前、治疗后第3天、第7天D-乳酸跨肺梯度的差异,分析D-乳酸跨肺梯度诊断肺炎的特异度和灵敏度,分析其与肺损伤评分(LIS)、临床肺部感染评分(CPIS)、氧合指数和血清降钙素原(PCT)水平的关系。结果与非肺炎组相比,肺炎组D-乳酸跨肺梯度显著升高[(163.84±10.72)ng/mL vs.(30.33±7.25)ng/mL,P<0.01)],以106.11ng/mL为截断值,D-乳酸跨肺梯度诊断肺炎的灵敏度为90.7%,特异度为75.5%;D-乳酸跨肺梯度与LIS及CPIS存在直线相关关系(分别为r=0.554,P<0.01;r=0.543,P<0.01)。结论 D-乳酸跨肺梯度与肺部感染密切相关,有望成为快速诊断肺炎及判断疗效的指标。

Objective To study the role of D-lactate gradient across the lung in the rapid diagnosis of pneumonia and evaluation of therapeutic efficacy. Methods Patients were divided into pneumonia group （n= 46） and non-pneumonia group （n=28） in ICU. D-lactate gradient across the lung were calculated by the difference between hrterial and mixed-venous D-lactate concentrations before the treatment.after 3 and 7 days of treatment. Serum procalcitonin （PCT）, Oxygenation index, the lung injury score （LIS） and clinical pulmonary infection score（CPIS） were recorded at the same time. Results The mean D-lactate gradient across the lung in pneumonia group was significantly higher than that in non-pneumonia group [（163.84 ± 10.72） ng/mL vs. （30. 33 ± 7.25） ng/mL, P〈0.01） -before treatment. Using a cut-off value of 106. 11 ng/mL,D-lactate gradient across the lung＇s sensitivity for diagnosis pneumonia was 90. 7 % and its＇ specificity was 75.5 %. D-lactate gradient across the lung correlated with LIS（r= 0. 554, P〈0. 01） and CPIS（r=O. 543,P〈0. 01）. Conclusion D-lactate gradient across the lung correlates with lung injury and pulmonary infection positively and may be a potential biomarker for rapid diagnosis of pneumonia.