What should define optimal correction of metabolic acidosis in chronic kidney disease?

Correction of metabolic acidosis is an important goal in the management of patients with chronic kidney disease (CKD). However, there is no consensus as to what constitutes an optimal correction of metabolic acidosis in this setting - various expert groups from around the world have set different goals for serum bicarbonate levels for patients with CKD. Accumulating evidence seems to indicate that achieving an arterial pH closer to the upper limit of the reference range may have even greater benefits than maintaining the arterial pH closer to the lower limit of the reference range. This benefit seems to be particularly relevant for patients with protein-energy wasting and we present a review of the evidence that supports this argument. Routine measurement of arterial pH, however, is not feasible in clinical practice; using the Henderson equation, a high-normal arterial pH is generally expected to be associated with a serum bicarbonate level of 24-30 mEq/l and should be the therapeutic goal for chronic kidney disease patients with protein-energy wasting.