Clinical Lab ( Osmolality )

The osmotic effect of solute concentration plays a key role in homeostasis. Solute concentration determines to large degree the intracellular and extracellular volume and tonicity. Many poisons, medications and diseases effect the balance between the intracellular and extracellular fluid volumes.
A serum osmolality test measures the amount of chemicals dissolved in the liquid part (serum) of the blood. Serum osmolality can be calculated by measuring the amounts of sodium, glucose, and blood urea nitrogen (BUN) in the blood.