Lactate Concentration, Base Excess (SBE), and Alactic Base Excess (ABE) as Predictors of ICU Outcome in Patients with Sepsis and Septic Shock: An Observational Study

INTRODUCTION: Shock is a life-threatening hemodynamic emergency leading to hypoperfusion of tissue causing severe hyperkalaemia and metabolic changes at cellular level. ABE is the sum of base excess and lactate, representing the concentration of abnormal strong acids other than lactate in plasma. Negative ABE is a predictor of mortality. ABE clearly differs from the anion gap because anion gap does not distinguish between lactate and other fixed acids. We conducting study to established correlation between ABE & mortality in patients with sepsis and septic shock as prospective studies on ABE are limited. OBJECTIVES: To investigate SBE, lactate, and ABE measured on admission to ICU as a predictors of ICU mortality. MATERIALS AND METHODS: A Prospective observational study conducted in 20 bed mixed ICU of Department of CCM SGPGIMS Lucknow from August 2023-Oct 2024. Demographics, Severity scores (APACHE-II, SOFA, CCI, VIS), Lab investigations (Hemogram, LFT, RFT, ABG collected, SBE and ABE calculated at ICU admission, 24hrs and 48hrs. At 28 days patients were grouped as survivors and non-survivors. Statical analysis was done using SPSS 16 software. A ROC curve used to correlate ABE to 28 days mortality. RESULTS: Out of 94 patients, 38 met the inclusion criteria. At day 28, 20 were grouped as survivor whereas 18 were non-survivors. In non survivors median age was 54, 56% was male, BMI was 24.06(22.04-27.14). At admission APACHE-II was 22.5(15-28), SOFA 20(10-70) and VIS was 20 (10-70), which were significantly higher in Non-survivors. Non-survivors also had significantly higher Negative SBE -6.62 vs -3.63 (P value < 0.05), ABE -4.18 vs -1.1 (P value < 0.05) and more need of RRT 59% vs 40% (P value 0.09). The Pearson correlation analysis showed good correlation between SBE, ABE at admission, at 24hrs and 28 days ICU outcomes. DISCUSSIONS/CONCLUSIONS: Our preliminary results show significant correlation between ABE, SBE and 28 days ICU mortality and ABE and SBE Is an independent mortality predictor. Further large studies are needed.