A client with asthma develops respiratory acidosis. Based on this diagnosis, what should the nurse expect the client's serum potassium level to be?

In respiratory acidosis, the body retains CO2, leading to increased hydrogen ion concentration and a drop in blood pH. As pH decreases, serum potassium levels increase due to the movement of potassium out of cells to compensate for the acidosis. Elevated serum potassium levels are expected in respiratory acidosis. Choice A ('normal') is incorrect because potassium levels are expected to be elevated in respiratory acidosis. Choice C ('low') is incorrect as potassium levels rise in this condition. Choice D ('unrelated to the pH') is incorrect as serum potassium levels are directly impacted by changes in pH in respiratory acidosis.