OBJECTIVE: To compare the 28-d mortality in two clinical patterns of septic shock: hyperlactatemic patients with hypoperfusion context and hyperlactatemic patients without hypoperfusion context.
METHODS: This prospective comparative observational study carried out on 135 adult patients with septic shock that met Sepsis-3 definitions compared patients with hyperlactatemia in a hypoperfusion context (Group 1, n = 95) and patients with hyperlactatemia in a non-hypoperfusion context (Group 2, n = 40). Hypoperfusion context was defined by a central venous saturation less than 70%, central venous-arterial PCO2 gradient [P(cv-a)CO2] ≥ 6 mmHg, and capillary refilling time (CRT) ≥ 4 s. The patients were observed for various macro and micro hemodynamic parameters at regular intervals of 0 h, 3 h, and 6 h. All-cause 28-d mortality and all other secondary objective parameters were observed at specified intervals. Nominal categorical data were compared using the χ2 or Fisher\'s exact test. Non-normally distributed continuous variables were compared using the Mann-Whitney U test. Receiver operating characteristic curve analysis with the Youden index determined the cutoff values of lactate, CRT, and metabolic perfusion parameters to predict the 28-d all-cause mortality. A P value of < 0.05 was considered significant.
RESULTS: Patient demographics, comorbidities, baseline laboratory, vital parameters, source of infection, baseline lactate levels, and lactate clearance at 3 h and 6 h, Sequential Organ Failure scores, need for invasive mechanical ventilation, days on mechanical ventilation, and renal replacement therapy-free days within 28 d, duration of intensive care unit stay, and hospital stay were comparable between the two groups. The stratification of patients into hypoperfusion and non-hypoperfusion context did not result in a significantly different 28-d mortality (24% vs 15%, respectively; P = 0.234). However, the patients within the hypoperfusion context with high P(cv-a)CO2 and CRT (P = 0.022) at baseline had significantly higher mortality than Group 2. The norepinephrine dose was higher in Group 1 but did not achieve statistical significance with a P > 0.05 at all measured intervals. Group 1 had a higher proportion of patients requiring vasopressin and the mean vasopressor-free days out of the total 28 d were lower in patients with hypoperfusion (18.88 ± 9.04 vs 21.08 ± 8.76; P = 0.011). The mean lactate levels and lactate clearance at 3 h and 6 h, CRT, P(cv-a)CO2 at 0 h, 3 h, and 6 h were found to be associated with 28-d mortality in patients with septic shock, with lactate levels at 6 h having the best predictive value (area under the curve lactate at 6 h: 0.845).
CONCLUSIONS: Septic shock patients fulfilling the hypoperfusion and non-hypoperfusion context exhibited similar 28-d all-cause hospital mortality, although patients with hypoperfusion displayed a more severe circulatory dysfunction. Lactate levels at 6 h had a better predictive value in predicting 28-d mortality than other parameters. Persistently high P(cv-a)CO2 (> 6 mmHg) or increased CRT (> 4 s) at 3 h and 6 h during early resuscitation can be a valuable additional aid for prognostication of septic shock patients.
目的:比较两种临床类型感染性休克的28天死亡率:低灌注的高乳酸血症患者和无低灌注的高乳酸血症患者。
方法:这项前瞻性观察性比较研究对135例符合脓毒症-3定义的感染性休克成年患者进行了比较,比较了低灌注环境中的高乳酸血症患者(第1组,n=95)和非低灌注环境中的高乳酸血症患者(第2组,n=40)。低灌注背景由中心静脉饱和度低于70%定义。中心静脉-动脉PCO2梯度[P(cv-a)CO2]≥6mmHg,和毛细血管再充盈时间(CRT)≥4s。每隔0h观察患者的各种宏观和微观血流动力学参数,3h,和6小时。在指定的时间间隔观察全因28天死亡率和所有其他次要目标参数。使用χ2或Fisher精确检验比较标称分类数据。使用Mann-WhitneyU检验比较非正态分布连续变量。用Youden指数进行受试者工作特征曲线分析,确定乳酸的截止值,CRT,和代谢灌注参数来预测28d全因死亡率。<0.05的P值被认为是显著的。
结果:患者人口统计,合并症,基线实验室,重要参数,感染源,基线乳酸水平,和乳酸清除率在3小时和6小时,序贯器官衰竭评分,需要有创机械通气,机械通气的天数,和28d内无肾脏替代治疗日,重症监护病房的住院时间,两组之间的住院时间相当。将患者分层为低灌注和非低灌注的背景并没有导致显著不同的28天死亡率(24%vs15%,分别为;P=0.234)。然而,在低灌注背景下,基线时高P(cv-a)CO2和CRT(P=0.022)的患者死亡率显著高于第2组.第1组的去甲肾上腺素剂量较高,但在所有测量间隔均未达到统计学意义,P>0.05。第1组需要加压素的患者比例较高,而灌注不足的患者在28d中的平均无血管加压素天数较低(18.88±9.04vs21.08±8.76;P=0.011)。3h和6h的平均乳酸水平和乳酸清除率,CRT,P(cv-a)CO2在0h时,3h,发现6小时与感染性休克患者的28天死亡率相关,6h时的乳酸水平具有最佳预测价值(6h时乳酸曲线下面积:0.845)。
结论:符合低灌注和非低灌注背景的脓毒性休克患者表现出相似的28天全因住院死亡率,尽管低灌注患者表现出更严重的循环功能障碍。与其他参数相比,6h时的乳酸水平在预测28d死亡率方面具有更好的预测价值。在早期复苏期间,在3h和6h持续升高P(cv-a)CO2(>6mmHg)或增加CRT(>4s)可能是预测感染性休克患者的有价值的额外帮助。