ARUP's Laboratory Test Directory

Potassium, Plasma or Serum : 0020002

Mnemonic: K

Methodology: Quantitative Ion-Selective Electrode
Performed: Sun-Sat
Reported: Within 24 hours
Specimen Required: Patient Prep: Patient should avoid exercise of arm or hand before and during collection.

Collect: Plasma separator tube or serum separator tube.

Specimen Preparation: Allow serum tube to clot completely at room temperature. Separate serum or plasma from cells within 2 hours of collection. Transfer 1 mL serum or plasma to an ARUP Standard Transport Tube. (Min: 0.2 mL)

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: Urine (refer to Potassium, Urine, ARUP test code 0020849). Specimens collected in citrate, EDTA, potassium oxalate, or sodium fluoride. Hemolyzed specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 2 weeks; Refrigerated: 2 weeks; Frozen: 6 months

Reference Interval:
0-7 days: 3.2-5.5 mmol/L
8 days-1 month: 3.4-6.0 mmol/L
2-6 months: 3.5-5.6 mmol/L
7-11 months: 3.5-6.1 mmol/L
1 year and older: 3.3-5.0 mmol/L
CPT Code(s): 84132