Mahajan Rubina Khullar, Peter John Victor, John George, Graham Petra L, Rao Shoma V, Pinsky Michael R
Medical Intensive Care Unit, Division of Critical Care Medicine, Christian Medical College, Vellore, Tamil Nadu, India.
Department of Statistics, Macquarie University, Sydney, Australia.
Indian J Crit Care Med. 2015 Oct;19(10):580-6. doi: 10.4103/0972-5229.167035.
Tissue hypoperfusion is reflected by metabolic parameters such as lactate, central venous oxygen saturation (ScvO2) and the veno-arterial CO2 (vaCO2) difference. We studied the relation of these parameters over time and with outcome in patients with severe septic shock.
In this single-center, prospective observational cohort study, adult patients (≥18 years) with circulatory shock were included. Echocardiography and simultaneous arterial and venous blood gases were done on enrolment (0 h) and at 24, 48 and 72 h. The partial pressure of CO2, lactate and ScvO2 were recorded from the central venous blood samples. The vaCO2 was calculated as the difference in CO2 between paired venous and arterial blood gas samples.
Of the 104 patients with circulatory shock, 79 patients (44 males) with septic shock aged 49.8 (standard deviation ± 14.6) years and with sequential organ failure assessment (SOFA) score of 11.0 ± 3.4 were included. 71 patients (89.9%) were ventilated (11.4 ± 12.3 ventilator-free days). The duration of hospitalization was 16.6 ± 12.8 days and hospital mortality 50.6%. Lactate significantly decreased over time with a greater decrement in survivors than nonsurvivors (-0.35 vs. -0.10, P < 0.001). For every l/min increase in cardiac output, vaCO2 decreased by 0.34 mmHg (P = 0.006). There was no association between ScvO2 and mortality (P = 0.930). 0 h SOFA and vaCO2 ≤6 mmHg were strongly associated (P = 0.005, P = 0.018, respectively) with higher odds of mortality. However, this association was evident only in those with ScvO2 >70% and not in ScvO2 ≤70%.
In septic shock, vaCO2 ≤6 mmHg is independently associated with mortality, particularly in those with normalized ScvO2 consistent with metabolic microcirculatory abnormalities in these patients.
组织灌注不足可通过代谢参数反映出来，如乳酸、中心静脉血氧饱和度（ScvO2）以及动静脉二氧化碳分压差（vaCO2）。我们研究了这些参数随时间的变化关系以及它们与严重脓毒症休克患者预后的关系。
在这项单中心前瞻性观察队列研究中，纳入了成年循环休克患者（≥18岁）。在入组时（0小时）以及24、48和72小时进行超声心动图检查以及同步动脉和静脉血气分析。从中心静脉血样本中记录二氧化碳分压、乳酸和ScvO2。vaCO2通过配对静脉和动脉血气样本之间的二氧化碳差值计算得出。
在104例循环休克患者中，纳入了79例脓毒症休克患者（44例男性），年龄为49.8（标准差±14.6）岁，序贯器官衰竭评估（SOFA）评分为11.0±3.4。71例患者（89.9%）接受了机械通气（无机械通气天数为11.4±12.3天）。住院时间为16.6±12.8天，医院死亡率为50.6%。乳酸随时间显著下降，存活者的下降幅度大于非存活者（-0.35对-0.10，P<0.001）。心输出量每增加1升/分钟，vaCO2下降0.34mmHg（P=0.006）。ScvO2与死亡率之间无关联（P=0.930）。0小时SOFA和vaCO2≤6mmHg与较高的死亡几率密切相关（分别为P=0.005，P=0.018）。然而，这种关联仅在ScvO2>70%的患者中明显，而在ScvO2≤70%的患者中不明显。
在脓毒症休克中，vaCO2≤6mmHg与死亡率独立相关，特别是在ScvO2正常的患者中，这与这些患者的代谢性微循环异常一致。
