BACKGROUND Acute circulatory failure is critical in ICU patients. CO2-O2-derived indices including the central venous-to-arterial CO2 difference (P(v-a)CO2 gap) and the P(v-a)CO2 gap/Ca-vO2 ratio are markers for global metabolic demand and tissue hypoxia. RESEARCH QUESTION Does a resuscitation strategy using CO2-O2-derived indices improve tissular hypoperfusion compared to standard care? STUDY DESIGN AND METHODS We conducted a randomized, prospective, multicenter, single-blind study in three ICUs. Patients aged 18 years or older with acute circulatory failure and arterial blood lactate levels ≥ 3 mmol/L were included. Patients were randomized to receive either a CO2-O2-derived algorithm-based treatment or standard clinical practice. The primary outcome was lactate clearance >10% within 2 hours. Secondary outcomes include SOFA, mortality. RESULTS Of the 179 patients enrolled (90 control, 89 treatment), there was no significant difference in achieving a lactate clearance over 10% at two hours between the control (50%) and interventional groups (43.8%), p=0.497. At 2 hours, the median change in lactate levels in the control group was -10.53% [-29.27; 5.68] while in the interventional group, it was -2.70% [-22.58; 19.1], p=0.096. Secondary outcomes did not differ between groups in SOFA scores (6 [3;9] vs 7 [4;10], p=0.719), ICU and hospital length of stay (4.5 days [2.0;10.8] vs 5.0 [2.0;10.0], p=0.963 and 11 days [3.0;27.0] vs 10 [3.0;21.0], p=0.493), or 28-day mortality (44.9% vs 33.3%, p=0.150). INTERPRETATION Algorithm-based resuscitation using CO2-O2-derived indices did not improve lactate clearance or clinical outcomes compared to standard care. Further research needed to identify specific patient subgroups who may benefit from this approach.

中文翻译：

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基于 CO2-O2 衍生指数的急性循环衰竭治疗：Lactel 随机多中心研究。


背景 急性循环衰竭在 ICU 患者中至关重要。CO2-O2 衍生指数，包括中心静脉与动脉 CO2 差异 （P（v-a）CO2 间隙）和 P（v-a）CO2 间隙/Ca-vO2 比率，是整体代谢需求和组织缺氧的标志。研究问题 与标准护理相比，使用 CO2-O2 衍生指数的复苏策略是否能改善胎圈低灌注？研究设计和方法 我们在三个 ICU 进行了一项随机、前瞻性、多中心、单盲研究。纳入 18 岁或以上的急性循环衰竭和动脉血乳酸水平≥ 3 mmol/L 的患者。患者被随机分配接受基于 CO2-O2 衍生的算法治疗或标准临床实践。主要结局是 2 小时内乳酸清除率 >10%。次要结局包括 SOFA、死亡率。结果 在入组的 179 例患者 （90 例对照组，89 例治疗组） 中，对照组 （50%） 和介入组 （43.8%） 在 2 小时内达到乳酸清除率超过 10% 无显著差异，p=0.497。2 小时时，对照组乳酸水平的中位变化为 -10.53% [-29.27;5.68]，而干预组为 -2.70% [-22.58;19.1]，p=0.096。次要结局在组间 SOFA 评分无差异 （6 [3;9] 第 7 节 [4;10]，p=0.719）、ICU 和住院时间 （4.5 天 [2.0;10.8] 对比 5.0 [2.0;10.0]，p=0.963 和 11 天 [3.0;27.0] vs 10 [3.0;21.0]，p=0.493）或 28 天死亡率 （44.9% vs 33.3%，p=0.150）。解释 与标准护理相比，使用 CO2-O2 衍生指数的基于算法的复苏并没有改善乳酸清除率或临床结局。需要进一步的研究来确定可能从这种方法中受益的特定患者亚组。