Analysis of blood gas beyond bicarbonate in outpatients with stage 3–5 chronic kidney disease

Abstract

Abstract Objectives Metabolic acidosis is a common disorder seen in course of chronic kidney disease (CKD). In this study, we aimed to investigate the association of Base excess (BE), Anion gap (AG) and Delta Ratio with progression of CKD, renal replacement therapy (RRT) requirement and mortality in patients with stage 3–5 CKD. Methods A total of 212 patients with stage 3–5 CKD were included in this study. Patients were divided into two groups according to the baseline BE level. Patients were also grouped according to the delta ratio such as non- AG, High AG and mixed type. Results Mean BE level was significantly lower (−4.7 ± 4.0 vs. −3.3 ± 4.3; p=0.02) in patients with CKD progression. The patients in group 1 (n: 130) (Be<−2.5) revealed more CKD progression (%53 vs. %32; p=0.002), and RRT requirement (%35 vs. %15; p=0.001). Baseline BE <−2.5 (odds ratio, 0.38; 95% CI, 0.16 to 0.91; p<0.05) and baseline GFR (odds ratio, 0.94; 95% CI, 0.90 to 0.97; p<0.001) were independently related to RRT requirement. Delta BE was independently associated with mortality (odds ratio, 0.90; 95% CI, 0.85–0.96; p<0.01). Conclusions Low BE levels were associated with CKD progression and RRT requirement. BE change is associated with mortality during the follow-up of those patients.