Quantifying the Deficits of Body Water and Monovalent Cations in Hyperglycemic Emergencies.

Hyperglycemic emergencies cause significant losses of body water, sodium, and potassium. This report presents a method for computing the actual losses of water and monovalent cations in these emergencies. We developed formulas for computing the losses of water and monovalent cations as a function of the presenting serum sodium and glucose levels, the sum of the concentrations of sodium plus potassium in the lost fluids, and body water at the time of hyperglycemia presentation as measured by bioimpedance or in the initial euglycemic state as estimated by anthropometric formulas. The formulas for computing the losses from hyperglycemia were tested in examples of hyperglycemic episodes. The formulas were tested in two patient groups, those with or without known weight loss during the development of hyperglycemia. In the first group, these formulas were applied to estimate the losses of body water and monovalent cations in (a) a previously published case of a boy with diabetic ketoacidosis and known weight loss who, during treatment not addressing his water deficit, developed severe hypernatremia and (b) a comparison of water loss computed by this new method with the reported average fluid gained during treatment of the hyperglycemic hyperosmolar state in a published study. In the second group, the formulas were applied in hypothetical subjects with varying levels of initial body water, serum sodium, and glucose at the time of hyperglycemia and sums of sodium and potassium concentrations in the lost fluids. Losses of body water and monovalent cations, which determine the severity of dehydration and hypovolemia, vary significantly between patients with hyperglycemic emergencies presenting with the same serum glucose and sodium concentrations. These losses can be calculated using estimated or measured body water values. Prospective studies are needed to test this proof-of-concept report.