Hyperglycemia in advanced renal failure: sodium and water metabolism

The pathophysiology of anuric hyperglycemia is characterized by changes in extracellular fluid volume and in effective osmolality. We studied these changes in 7 anuric patients during correction (seven instances) or development (one instance) of hyperglycemia. During observations, intakes and outputs of fluids were negligible and weights did not change. Pulmonary edema, present in hyperglycemia in six instances, disappeared with normalization of glucose concentration in five instances. While glucose was rising, before study, thirst and water intake were pronounced in six instances; in three, normalization of glucose concentration uncovered true hyponatremia. For the same change in blood glucose, changes in effective osmolality were greatest in patients with anasarca.