Prognostic value of arterial lactate content combined with base excess in patients with sepsis: a retrospective study

Abstract

To study the prognostic value of arterial lactate combined with base excess (BE) in sepsis patients. Clinical data of patients admitted to intensive care unit (ICU) from July 2009 to December 2012 were retrospectively analyzed. Patients were divided into survivor group and non-survivor group, and the arterial blood lactate and BE concentrations were compared between groups. The receiver operating characteristic curve (ROC curve) was drawn and area under the ROC curve (AUC) was calculated to analyze the function of arterial lactate, BE and their combination in judging the prognosis of sepsis. The best cut-off values of arterial lactate and BE for sepsis prognosis were searched. One hundred and eighteen patients were enrolled with 75 in survivor group and 43 in non-survivor group. There were significant differences in arterial lactate [1.20(0.90) mmol/L, 2.30(1.90) mmol/L] and BE (0.44 ± 5.13 mmol/L, -4.35 ± 4.86 mmol/L) between two groups (both P=0.000). The AUC for mortality prediction was 0.805, 0.755 and 0.822 for arterial blood lactate, BE, and their combination respectively. Using arterial lactate higher than 1.7 mmol/L and BE lower than -3 mmol/L as cut-off values, a better sensitivity (79.1% and 69.8%) and positive predictive value (3.955 and 2.493) can be obtained. Combination of arterial lactate and BE can be a better indicator of prognosis in sepsis patients.