What is expected to happen to potassium with a 0.10 change in pH?

A change in pH can significantly impact the balance of electrolytes, especially potassium, in the body. When considering a decrease in pH, meaning the body becomes more acidic, potassium ions tend to shift out of cells into the extracellular fluid. This process occurs because hydrogen ions (H+) compete with potassium (K+) for movement across the cell membrane; in an acidic environment, more hydrogen ions enter the cells, prompting potassium to move out.

The numerical relationship commonly referenced is that for every 0.1 change in pH, there is an expected shift in serum potassium concentration of approximately 0.6 mEq/L in the same direction. Therefore, for a decrease in pH, potassium concentrations in the serum are expected to increase. This indicates that acidosis leads to hyperkalemia due to the movement of potassium ions from inside the cells to the outside.

In summary, a decrease in pH corresponds to an increase in serum potassium levels, supporting the reasoning behind the chosen correct answer.