Potassium
Label Mnemonic: K
Epic code: LAB114
Order form: Laboratory Requisition
Supply order: Supply Order Form
Billing: Billing Policies
CPT code: 84132
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL whole blood in light green top tube or ONE Microtainer® for pediatric patients.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
3.5 - 5.0  mEq/L

Pediatric Reference Ranges:

Age       Range    Units
<10 days  3.5-6.0  mEq/L
>10 days  3.5-5.0  mEq/L

Critical value: Adults >16 years       <2.8 mEq/L and >6.2 mEq/L
                Pediatric (0-15 years) <3.0 mEq/L and >6.5 mEq/L
Comments:
Refer to BD Microtainer® Tubes product sheet for detailed sample collection instructions.

Avoid hemolysis. False elevations may occur in specimens which are not processed promptly (to separate serum from RBC's). Plasma samples drawn in heparin tubes have values slightly lower than serum.
Test Limitations:
Icterus: No significant interference up to an I index of 60.

Hemolysis: Significant positive interference at an H index greater than 100 (approximate hemoglobin concentration: 100 mg/dL.

Lipemia (Intralipid): No significant interference up to an L index of 2000. There is poor correlation between turbidity and triglycerides concentration.
Methodology:
Ion Selective Electrode
Sample Processing:
Centrifuge at a speed and time necessary to get barrier separation of plasma/serum and cells within 1 hour of collection. Send specimen in original tube. Do Not transfer to another tube.
Each sample must be labeled with at least TWO full patient identifiers (First/Last Name & DOB are sufficient for non-UIHC affiliated clients) to avoid sample rejection/delays.
Sample Storage:
Refrigerate.
All sample storage requirements are intended for delivery to UIHC within 24 hours of collection for testing. If samples won't arrive in this time period, please call the UIHC Core Lab for alternative storage/shipping instructions (319-356-3527).
Transport Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place completed requisition into outside pocket of bag.
Transport in cooler with refrigerated coolant packs.
CPT Code:
84132
 
See also:
Potassium-Other, Body Fluid
 
See Additional Information:
Chemistry Critical Lab Values