Correlation of Serum Lactate Levels in Survival of Patients with Sepsis

Background: Sepsis is a life-threatening condition characterized by a dysregulated host response to infection, leading to organ dysfunction and high mortality rates. This study aimed to investigate the association between serum lactate levels and 28-day mortality in patients with sepsis. Methods: A prospective observational study was conducted in the intensive care unit of a tertiary care hospital. Adult patients with sepsis (n=80) were enrolled, and serum lactate levels were measured at baseline and at 12, 24, and 48hours. The primary outcome was 28-day mortality. Logistic regression analysis and Cox proportional hazards regression were used to assess the association between lactate levels and mortality. Results: Non-survivors had significantly higher initial serum lactate levels compared to survivors (4.3 mmol/L vs. 3.2 mmol/L, p<0.001). The optimal cut-off value for initial serum lactate in predicting 28-day mortality was 3.8 mmol/L (sensitivity 78.6%, specificity 71.2%, AUC 0.81). Patients with serum lactate levels >3.8 mmol/L had a significantly lower 28-day survival rate (39.3% vs. 82.4%, p<0.001). In the multivariate analysis, APACHE II score (hazard ratio 1.09, 95% CI 1.03-1.16, p=0.003) and initial serum lactate (hazard ratio 1.58, 95% CI 1.23-2.03, p<0.001) were independent predictors of mortality. Conclusion: Serum lactate levels and lactate clearance are significant predictors of 28-day mortality in patients with sepsis. Incorporating lactate measurement into sepsis management protocols can help guide treatment decisions and improve patient outcomes.