Test Code LAB436 Potassium, Urine, 24 Hour
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Methodology
Indirect Ion-Selective Electrode (ISE)
Literature Reference:
Package insert: ISE/Na, K, Cl. Roche Corporation, 12/2020.
Specimen Requirements
Specimen Type: Urine, 24 hour
Container/Tube: Plain, brown urine container
Specimen Volume: Entire collection
Collection Instructions: No additive. Refrigerate specimen during collection.
Additional Information:
1. Starting and ending times of collection are required.
2. Follow instructions in Urine Collection in General Information.
3. Containers with preservatives are NOT acceptable.
Day(s) Test Set Up
Monday through Sunday
Turnaround Time:
STAT: 1 hour after receipt in laboratory
Routine: 2 to 4 hours after receipt in laboratory
Test Classification and CPT Coding
81050-Volume measurement for timed collection
84133-Potassium
Reference Values
Varies greatly with diet
Commonly observed levels on an average diet are 25-125 mmol/24 hours.
Literature Reference:
Rifai N, Horvath AR, Wittwer AT eds: Textbook of Clinical Chemistry and Molecular Diagnostics 6 th ed: Chapter 60, p. 1324, Elsevier, St. Louis, MO 2018.
Specimen Transport Temperature
Ambient
Additional Information
For BJH Laboratory Use Only
Analyte Stability:
Specimen must be kept refrigerated during collection and before delivery to limit bacterial growth.
Laboratory Processing Instructions:
Test performed in BJH Core Lab. Mix urine well. Record volume, period, and pH on request form. Using 13x100 test tubes, prepare a 7-mL aliquot and deliver to the automated line for centrifugation and delivery to Cobas 8000 for analysis. Completed specimen is stored refrigerated for 5 days.
Special Instructions
See Urine Collection information under General Information.
See Analyte Stability Chart under General Information for a complete list.
LOINC Code Information
Name | LOINC Code |
Potassium in 24 hour urine | 2829-0 |
Collection duration | 13362-9 |
Volume of urine | 19153-6 |