Skip to Content
UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Potassium

Test Code(s): K

CPT Code(s): 84132

Test Description: Included In: Electrolytes Panel, Basic Metabolic Panel, Comprehensive Metabolic Panel

Methodology: Ion Selective Electrode

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: 1 hour.
Routine: 4 hours.


Specimen Requirements

Specimen: Blood

Collection Container: Preferred: Green cap with yellow ring (PST)
Also Acceptable: Green top, Red cap with yellow ring (SST), Red top

Collection Volume: Preferred: 1 mL
Pediatrics: 0.5 mL

Sample Analyzed: Plasma or serum

Volume Required: Preferred: 0.5 mL
Pediatrics: 0.2 mL

Specimen Processing: Centrifuge.  Redraw specimen if hemolysis is present.  If a complete barrier has not formed, transfer cell-free plasma/ serum to plastic vial.  Refrigerate.

Specimen Transport: Transport specimen to the laboratory. Transport with coolant pack if coming from outreach location.

Unacceptable Criteria: Hemolyzed specimens or whole blood specimens greater than 2 hours old when received by the laboratory are not acceptable.

Stability: Ambient: 24 hours
Refrigerated: PST - 48 hrs; if off cells or SST - 4 days
Frozen: Not acceptable


Interpretation

Reference Interval:
 Age  mmol/L
 0-17 years  3.5-5.2 
 18 years and up  3.5-4.8

  

Critical Calls: View

K

Back to Lab Test Directory Index