Prognostic implication of serum anion gap in sepsis: A prospective-observational study
DOI:
https://doi.org/10.61529/idjp.v35i1.506Abstract
Background: To investigate the prognostic significance of serum anion gap (SAG) in patients with sepsis in terms of length of hospital stay, Intensive Care Unit (ICU) admission and in hospital mortality.
Material and Methods: This prospective observational cohort study was conducted in the emergency department of ISRA University Hospital Hyderabad from 1 May 2025 to 31 October 2025. Patients aged ≥ 18 years, with qSOFA score of 2 or more on admission were included in the study. Small amount of blood samples were drawn by using a 5cc syringe. SAG was calculated with the help of serum electrolytes. Data were analyzed using SPSS.
Results: A total of 360 patients with sepsis were analyzed; 219 (60.8%) were male and 141 (39.2%) females, with a mean age of 58.06 ± 13.81 years. The mean serum anion gap (AG) was 14.46 ± 3.77 mEq/L, and the average hospital stay was 5.67 ± 3.38 days. Overall mortality was 43.6%. High AG was significantly more common in non-survivors than survivors (71.6% vs 9.4%, p < 0.001). High AG was associated with increased odds of mortality in both univariate (OR = 4.265; 95% CI: 2.384–7.629) and multivariate analyses (OR = 4.197; 95% CI: 2.338–7.524), confirming it as an independent predictor of mortality.
Conclusion: Higher SAG is associated with increased mortality, ICU admission, ventilator and inotropic support.
Keywords: Sepsis, Intensive care unit, Mortality, Serum AG, Lactate levels
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