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Potassium, whole blood (MtZ Only)

Item Value
Approval req'd? Yes, contact Blood Bank at x3-1313. Requires Blood Bank lab medicine resident's approval when test is ordered on transfused blood unit.
Available Stat? Yes
Test code KSB
Test group Potassium
Performed by Mt. Zion Chemistry
In House Availability Test available 24 hours per day 7 days per week
Method Ion selective electrode (ISE)
NCPL Radiometer ABL 800
MtZ Gem Premier 3500
Collection Instructions Fill syringe completely, remove needle, expel all bubbles and cap sample. Deliver immediately to lab for testing.
Container type Plastic syringe containing 100U of dry heparin
Amount to Collect 3 mL blood
Sample type Heparinized whole blood (Blood gas syringe only)
Preferred volume 3 mL blood
Min. Volume 1 mL blood
UCSF Rejection Criteria Samples submitted > 30 min. after collection. Samples with needle attached, containing large bubbles, unlabeled, mislabeled, clotted or of insufficient volume for testing.
Units mmol/L
Normal range
≤ 1 year 3.0-5.4 mmol/L
> 1 year 3.4-4.5 mmol/L
Critical value < 3.0 mmol/L or > 6.0 mmol/L
Synonyms K; K+; Electrolytes
Turn around times Stat 15 min, Routine 30 min
Additional information Hemolysis may artifactually increase the result. Levels in serum are normally 0.3 mmol/L higher than plasma levels due to liberation of potassium by platelets during clotting (c. 0.07 mmol/L per 100K platelets). Thus not only hemolysis but thrombocytosis can falsely elevate potassium levels, which can be circumvented by measuring plasma rather than serum potassium. Values < 1.5 or > 12 are automatically reassayed.
CPT coding 84132
LOINC code 6298-4
Last Updated 6/22/2016 12:46:50
Entry Number 767
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