Sign in →

Test Code NAS Sodium, Serum


Necessary Information


Patient's age and sex are required.



Specimen Required


Collection Container/Tube: 

Preferred: Serum gel

Acceptable: Red top

Submission Container/Tube: Plastic vial

Specimen Volume: 0.5 mL

Collection Instructions:

1. Serum gel tubes should be centrifuged within 2 hours of collection.

2. Red-top tubes should be centrifuged, and the serum aliquoted into a plastic vial within 2 hours of collection.


Useful For

Assessing acid-base balance, water balance, water intoxication, and dehydration

Reporting Name

Sodium, S

Specimen Type

Serum

Specimen Minimum Volume

0.25 mL

Specimen Stability Information

Specimen Type Temperature Time
Serum Refrigerated (preferred) 14 days
  Ambient  14 days

Reject Due To

Gross hemolysis Reject
Gross lipemia OK

Reference Values

<1 year: not established

≥1 year: 135-145 mmol/L

Method Description

An ion-selective electrode (ISE) makes use of the unique properties of ion-selective membrane to develop an electrical potential (electromotive force: EMF) for the measurements of ions in solution. Selective membrane is in contact with both the test solution and an internal filling solution. Due to the selectivity of the membrane, only the ions to be measured contribute to the EMF. The membrane EMF is determined by the difference in concentration of the test ion in the test solution and the internal filling solution. The EMF develops according to Nernst equation of a specific ion in solution.(Package insert: ISE indirect Na-K-Cl for Gen 2. Roche Diagnostics; 05/2024)

Day(s) Performed

Monday through Sunday

Report Available

Same day/1 to 2 days

Specimen Retention Time

1 week

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

84295

LOINC Code Information

Test ID Test Order Name Order LOINC Value
NAS Sodium, S 2951-2

 

Result ID Test Result Name Result LOINC Value
NAS Sodium, S 2951-2

Forms

If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:

-Kidney Transplant Test Request

-Cardiovascular Test Request Form (T724)