摘要目的 探讨感染性休克患者动脉血乳酸(Lac)水平及乳酸清除率(LCR)对预后预测的价值.方法 采用回顾性研究方法,选择2011年1月至2014年6月苏北人民医院重症医学科收治的资料完整的94例感染性休克患者,测定患者确诊为感染性休克时(初始值,0h)以及治疗后早期(3、6、24 h)的动脉Lac水平,并计算3、6、24 h的LCR.根据患者在重症加强治疗病房(ICU)预后分为生存组(48例)和死亡组(46例),分别统计两组患者不同时间点的Lac和LCR值,并对Lac、LCR与预后进行相关性分析,绘制受试者工作特征曲线(ROC),评价不同时间点Lac和LCR对预后的预测价值.结果 生存组治疗后Lac水平较初始值明显降低,而死亡组无明显改变.与死亡组比较,生存组早期Lac水平(mmol/L)均明显降低(0 h:3.80±2.14比5.75±3.21,3 h:2.05±1.04比5.03±2.53,6 h:1.80±0.77比4.40±2.02,24 h:1.35±0.43比4.90±2.72,P＜0.05或P＜0.01),LCR明显升高[3 h:50.00(72.35)％比13.51 (20.67)％,6 h:41.43 (58.42)％比22.00 (22.31)％,24 h:58.73 (29.94)％比18.92 (47.28)％,P＜0.05或P＜0.01].各时间点Lac水平与预后均呈正相关,治疗后6h、24 h的LCR与预后呈负相关.根据初始Lac水平分为低Lac组(＜2 mmol/L)、中Lac组(2 ～3 mmol/L)、高Lac组(≥4 mmol/L),随Lac水平增高,病死率明显增加[23.07％ (6/26)、50.00％ (8/16)、61.54％ (32/52),x 2=10.270,P=0.006].ROC曲线分析显示:24 h Lac的ROC曲线下面积(AUC)最大(为0.944),对预后评价的敏感度和特异度更高(分别为100％、78.3％),以24 h Lac临界值2.35 mmol/L将患者分为高、低Lac组,高Lac组病死率明显高于低Lac组[100.0％ (36/36)比17.24％ (10/58),x2=30.441,P=0.000].而24 h LCR的AUC也最大(为0.865),对预后评价的敏感度和特异度也更高(分别为83.3％、91.3％),以24 h LCR临界点36.8％将患者分为高、低LCR组,低LCR组病死率明显高于高LCR组[84.00％ (42/50)比9.09％ (4/44),x2=26.278,P=0.000].结论 感染性休克患者早期高Lac水平提示预后不佳,24 h Lac及LCR是评估感染性休克临床治疗效果及预后的指标.

abstractsObjective To explore the prognostic value of arterial blood lactate (Lac) levels and lactate clearance rate (LCR) in the patients with septic shock.Methods A retrospective study was conducted.Clinical data of 94 septic patients admitted in the Department of Critical Care Medicine in Subei People's Hospital from January 2011 to June 2014 were analyzed.The arterial blood Lac levels at the moment of diagnosis of septic shock (incipient value,0 hour) and early-stage after treatment (3,6 and 24 hours) were reviewed,and individual LCR was calculated at 3,6,24 hours for each patient.According to the outcome in intensive care unit (ICU),patients were divided into survival group (n =48) and death group (n =46).The Lac and LCR at different time points in two groups were analyzed,and the relationships between them and outcome were analyzed.The receiver-operating characteristic (ROC) curve was plotted to assess the value of Lac and LCR at different time points for predicting the outcome.Results Lac level after treatment in survival group was significantly lower than incipient value,but there was no obvious change in death group.Compared with death group,early Lac levels (mmol/L) in survival group were significantly reduced (0 hour:3.80 ± 2.14 vs.5.75±3.21,3 hours:2.05± 1.04 vs.5.03±2.53,6 hours:1.80±0.77 vs.4.40±2.02,24 hours:1.35±0.43 vs.4.90 ± 2.72,P ＜ 0.05 or P ＜ 0.01),the LCR was significantly increased [3 hours:50.00 (72.35)％ vs.13.51 (20.67)％,6 hours:41.43 (58.42)％ vs.22.00 (22.31)％,24 hours:58.73 (29.94)％ vs.18.92 (47.28)％,P ＜ 0.05 or P ＜ 0.01].The Lac levels at all time points were positively correlated with the outcome,and 6-hour and 24-hour LCR were negatively correlated with the outcome.According to the incipient Lac level,patients were divided into low Lac group (Lac ＜ 2 mmol/L),mild Lac group (Lac 2-3 mmol/L) and high Lac group (Lac ≥ 4 mmol/L).The mortality in low Lac group,mild Lac group,high Lac group was gradually increased [23.07％ (6/26),50.00％ (8/16),61.54％ (32/52),x2=10.270,P =0.006].ROC curves demonstrated that the area under ROC curve (AUC) of 24-hour Lac was the largest,0.944,and it was more sensitive and specific in the prognosis evaluation (100％ and 78.3％,respectively).According to the cut-off value of 24-hour Lac as 2.35 mmol/L,patients were divided into high Lac and low Lac groups,and mortality rate in high Lac group was significantly higher than that in low Lac group [100.0％ (36/36) vs.17.24％ (10/58),x2=30.441,P =0.000].The AUC of 24-hour LCR was the largest,0.865,and it was more sensitive and specific for the prognosis evaluation (83.3％ and 91.3％,respectively).According to the cut-off value of 24-hour LCR as 36.8％,patients were divided into high LCR group and low LCR group,and mortality rate in low LCR group was significantly higher than that in high LCR group [84.00％ (42/50) vs.9.09％ (4/44),x2=26.278,P =0.000].Conclusion Early high Lac in patients with septic shock prompts a poor prognosis,and 24-hour Lac levels and LCR are indicators of assessment of clinical therapeutic effect and prognosis of patients with septic shock.