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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Electrolytes, Whole Blood


CPT Code(s): 80051

Test Description: Test Component:

Sodium, Whole Blood; Potassium, Whole Blood; Chloride, Whole Blood;  and Total CO2, Whole Blood  (carbon dioxide)

Methodology: Ion Selective Electrode

Request Form: UWHC DOWNTIME Laboratory Request Form (UWH IPDOWNTIME, 4004202); Write in test if not on form.

Specimen Requirements

Specimen: Arterial, venous, or capillary

Collection Instructions: Radiometer "PICO"® syringes must be free of bubbles and clots. Two full Radiometer capillaries free of air bubbles and clots are needed for capillary blood. Do NOT place specimen on ice.

Collection Container: Preferred: Radiometer PICO® syringe
Also Acceptable: 2 full Radiometer capillary tubes, Green top

Collection Volume: Preferred: 1.5 mL
Pediatrics: 0.5 mL

Sample Analyzed: Whole Blood

Volume Required: Preferred: 1.5 mL
Pediatrics: 0.5 mL

Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220) immediately.  Specimen must arrive in the UWHC Core Lab within 30 minutes of collection.

Unacceptable Criteria: Clotted specimens, iced specimens, or specimens past stability time are not acceptable.

Stability: Ambient: 1 hour
Refrigerated: Not acceptable
Frozen: Not acceptable


Reference Interval:
 Sodium, WB  0 days and up: 137-144 mmol/L
 Potassium, WB  0-29 days:  4.0-5.9 mmol/L
   30 days-11 months:  4.0-5.3 mmol/L
   12 months and up:  3.6-5.0 mmol/L
 Chloride, WB  0 days and up: 97-106 mmol/L
 CO2, WB  0 days and up: 22-32 mmol/L

Critical Calls: View

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