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Updated: Mar 13, 2026

Identification and Quantification of Deranged Metabolites in Critically Ill Patients Using NMR-Based Metabolomics
Published on: November 29, 2024
Absolute lactate value vs relative reduction as a predictor of mortality in severe sepsis and septic shock
Sharukh Lokhandwala1, Lars W Andersen2, Sunil Nair3
1Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA; Harvard Medical School, Boston, MA; Massachussetts Institute of Technology, Cambridge, MA; Department of Medicine, Division of Pulmonary and Critical Care, University of Washington, Seattle, WA.
Purpose:
Lactate reduction, a common method of risk stratification, has been variably defined. Among patients with an initial lactate >4mmol/L, we compared mortality prediction between a subsequent lactate ≥4mmol/L to a <10% and <20% decrease between initial and subsequent lactate values.
Materials And Methods:
We performed a single-center retrospective study of patients presenting to the emergency department with an initial lactate ≥4mmol/L and suspected infection. Patients were stratified by lactate reduction using 3 previously identified definitions (subsequent lactate ≥4mmol/L, and <10% and <20% relative decrease in lactate) and compared using multivariable logistic regression. Sensitivity and specificity were compared using McNemar test.
Results:
A subsequent lactate ≥4mmol/L and a lactate reduction <20% were associated with increased in-hospital mortality (odds ratio [OR], 3.18; 95% confidence interval [CI], 1.24-8.16; P=.02 and OR, 3.11; 95% CI, 1.39-6.96; P=.006, respectively), whereas a lactate reduction <10% was not (OR, 1.13; 95% CI, 0.94-1.34; P=.11). A subsequent lactate ≥4mmol/L and a lactate reduction <20% were more sensitive than a lactate reduction <10% (72% vs 41%, P=.002 and 62% vs 41%, P=.008, respectively) but less specific (57% vs 76%, P<.001 and 67% vs 76%, P=.002, respectively).
Conclusions:
A subsequent lactate ≥4mmol/L and lactate reduction <20% were associated with increased in-hospital mortality, whereas a lactate reduction <10% was not. Sensitivity and specificity are different between these parameters.
