Normal Reference Ranges
Adult
275 - 295 mOsm/kg
Pediatric
275 - 295 mOsm/kg
Clinical Significance
Determines the concentration of solutes in blood. Crucial for working up hyponatremia and evaluating for toxic alcohol ingestions (osmolar gap).
Causes of High
- Dehydration
- Diabetes Insipidus
- Hyperglycemia
- Uremia
- Toxic alcohol ingestion (Methanol, Ethylene Glycol)
Causes of Low
- Overhydration
- SIADH
- Adrenal insufficiency