Laboratory Test Information Guide

Details for Electrolytes,Plasma

Test Name: Electrolytes,Plasma
Alternate Name(s): Sodium
Potassium
Chloride
CO2
GAP
Laboratory: Core
Specimen Type: 4.5 mL Green (Lithium Heparin) top Vacutainer

Pediatric:
0-2 yrs: 0.5 mL Green micropick tube.
2-10 yrs: 2 mL Green top
Collection Information: Collect blood aseptically in a Vacutainer tube.

Avoid hemolysis.

Serum from a 5 mL Gold top or 6 mL Red top is also acceptable.
Requisition: GENERAL LABORATORY REQUISITION
Test Schedule: As required
Turnaround time from when specimen
is received in testing laboratory:
 
Routine
4 hours
Stat
1 hour
 
Reference Range: 
Sodium:
135-145 mmol/L
Potassium:
3.5-5.0 mmol/L (<3 months: 4.0-6.5 mmol/L)
Chloride:
98-107 mmol/L
CO2:
22-29 mmol/L
Effective Date: 2008-11-15
Revised Date: 2014-02-25
Critical Value: Sodium: <120 or >160 mmol/L
Potassium: <3.0 or >6.0 mmol/L
Interpretive Comments: Of use in monitoring electrolyte status, interpretation of acid-base balance and evaluation of hydration status.

Potassium: potassium is largely intracellular cation and plasma levels are, at best, only a general guide to the total body potassium content. In some cases (e.g. untreated diabetes), plasma potassium may be increased when total body potassium is depleted.

CO2: for complete evaluation of acid-base status, Blood Gases should be ordered. Decreased in metabolic acidosis, increased in metabolic alkalosis, and chronic respiratory acidosis.

Gap calculation is Gap=Sodium-(Chloride+Bicarbonate)
Special Processing:  
Comments: Potassium results may be affected by hemolysis.
Method of Analysis: For Sodium, Potassium & Chloride: Indirect Ion Selective Electrodes

Co2: Enzymatic rate
Critical Information Required:  
Storage & Shipment: Serum/Plasma must be separated from the cells within 2 hours of collection. Store at 15-30 degrees Celsius for no longer than 8 hours. Specimen can be stored at 2-8 degrees Celsius for up to 48 hours. If analysis has not been started before 48 hours then the specimen must be frozen.
System Codes: 
Cerner
LYTE
 
Referred To:  

Questions? Comments? Contact Laura Gopaul