TABLE 4

Increasing diagnostic utility of the osmol gap

The osmol gap is the difference between the calculated serum osmolality and measured osmolality
Calculated serum osmolality =
(Sodium x 2) + (Glucose/18) + (Blood urea nitrogen/2.8)
An elevated osmol gap indicates osmotically active solutes in plasma that are not typically present under normal conditions, such as ethylene glycol, diethylene glycol, methanol, and their many metabolic products