Fig. 2

Sample plots demonstrating levels of variability. Representative graphs of serum bicarbonate over time are shown for 3 patients in each of the 3 variability categories. Low, medium, and high variability were defined based on tertiles of the mean value of VV (Variability Value) for each patient during follow-up: Low (mean VV ≤2.18 mEq/L), Medium (mean VV = 2.19 to 2.75 mEq/L), and High (mean VV ≥2.76 mEq/L)