CNS symptoms are often the most prominent. On the physical examination, carefully check for signs of volume depletion or, conversely, clues to an edematous disorder. Extreme hyponatremia may impair baroreceptor reflexes, giving rise to postural hypotension and a false impression of volume depletion. Hyperkalemia and metabolic acidosis coexisting with hyponatremia suggests adrenal insufficiency. This results from the osmotic effect of glucose drawing water out of cells, and the serum sodium rises when the hyperglycemia is corrected.
Helps rule out other potential causes of acute changes in neurologic status.