Osmolality Serum

Test Code

OSMO

CPT Codes
83930

Preferred Specimen

GREEN Lithium Heparin Plasma

Minimum Volume

0.5 mL

Other Acceptable Specimens

SST Serum Separator, Red No Gel

Transport Container

GREEN Lithium Heparin

Transport Temperature

Room Temperature

Specimen Stability

Room Temp: 48 Hours; Refrigerated: 48 Hours

Methodology
OSOM1 Osmometer

Reference Range

275-300 mOsm/kg; Critical : <240 or >330 mOsm/Kg

Clinical Significance

Serum osmolality measures dissolved particles in blood, crucial for diagnosing fluid/electrolyte imbalances, kidney issues, and poisonings by reflecting hydration status (high in dehydration, low in overhydration) and identifying excess solutes, helping differentiate causes of confusion, seizures, or coma, especially in cases of diabetes insipidus, diabetic ketoacidosis (DKA), or toxin ingestion (like methanol/ethylene glycol)

Performed By
RFGH Laboratory

Performing Laboratory
RFGH Laboratory

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.