Figure 1.

Schematic of effects of lactic acidosis on plasma K⁺. Elevation of lactate, an organic acid, causes lactic acidosis, which results in reduction of intracellular pH. The low pH in turn activates the Na⁺/H⁺ exchange in the cell, which pushes H⁺ out in exchange for Na⁺. The influx of Na⁺ intracellularly then activates the Na⁺/K⁺-ATPase, which results in intracellular shift of K⁺, leading to hypokalemia. Adapted from Figure 4 in Aronson PS, Giebisch G. Effects of pH on potassium: new explanations for old observations. J Am Soc Nephrol. 2011;22:1981–1989.² Copyright © 2011 by the American Society of Nephrology.