Sign in →

Test Code NA Sodium (Na+) LAB122

Performing Laboratory

UnityPoint The Finley Hospital

Test Method

Ion-Selective Electrode; Roche cobas Pro

Performance

Testing is performed Monday through Sunday.

Routine orders: Typically completed within 4 hours after the specimen arrives at the testing site.

STAT: Typically completed within 30 minutes after the specimen arrives at the testing site.

Specimen Requirement

  1. Lithium heparin plasma (Green) 
  2. Serum (Red/Gold): 0.5 mL
  3. Gel tubes are acceptable.
  4. It is recommended that the serum or plasma be separated from contact with cells within 2 hours from time of collection.
  5. Sodium specimens are stable for 14 days at 15-25°C and 2-8°C, and indefinitely when stored frozen at -20°C. 

Useful For

Sodium is the major extracellular cation and functions to maintain fluid distribution and osmotic pressure. Some causes of decreased levels of sodium include prolonged vomiting or diarrhea, diminished reabsorption in the kidney and excessive fluid retention. Common causes of increased sodium include excessive fluid loss, high salt intake and increased kidney reabsorption.

Reference Values

136‑145 mmol/L

Critical Values:
less than (<) 120 or greater than (>) 160mmol/L

CPT Code Information

84295 Chemistry: Sodium, serum, plasma or whole blood

LOINC Code Information

2951-2 Sodium [Moles/Volume] In Serum Or Plasma