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Potassium, Serum / Plasma
|Performed by||Parnassus, Mission Bay & Mt. Zion Chemistry|
|In House Availability||Test available 24 hours per day 7 days per week|
|Method||Ion Specific Electrode (ISE)|
|Container type||Gold top or Light Green top|
|Amount to Collect||1 mL blood Click here for Microdetermination info|
|Sample type||Serum, Heparinized plasma|
|Preferred volume||0.5 mL serum or plasma|
|Min. Volume||0.2 mL serum or plasma Click here for Microdetermination info|
1. Normal range for infants 0 to <1 year adopted from Soldin, Steven J., "Pediatric Reference Intervals", 6th edition, AACC Press, 2007, method 4.
2. Adult range used for children >1 year old.
3. Normal range for adults was determined by testing 271 male and female healthy blood donors at UCSF.
|Critical value||< 3.0 mmol/L or > 6.0 mmol/L|
|Synonyms||K; K+; Electrolytes|
|Stability||Room temperature 8 hours, refrigerated 2 days, frozen at -20C 1 week|
|Turn around times||STAT 1 hour, Routine 4 hours|
|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.|
|Last Updated||1/28/2015 3:05:46 PM|
|Lab Procedure Link||Click here for Procedure|