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Calcium, Ionized, Venous

See also Ionized Calcium

Specimen Type = Herapin Syringe with Green Top

Specimen Type

Test ID LAB5306
EPIC Order Calcium Ionized Venous (MG/DL)
CPT Code(s) 82330
Group/Individual Test Individual
Laboratory Core Laboratory-Blood Gas
Tube Station 31
Specimen Routine: 1 mL whole blood in 3cc syringe w/ lyophilized heparin in BG Kit, SafePICO Collection Kit, or Green Heparin – NO GEL. See Comments.
Micro:

0.5 mL whole blood in 1cc syringe w/ lyophilized heparin in BG Kit. See Comments.
Stability  

Room Temp/Refrigerated: 30 minutes

Frozen: NO
Availability Routine: 24 Hours/Day
STAT: Yes
Turnaround Time                10 Minutes 
Reference Range Normal: 4.4-5.4 mg/dL
Critical: <3.2 or >6.5 mg/dL
Comments
  • Green Sodium Heparin tubes are NOT acceptable and will be rejected.
  • Deliver Immediately to Blood Gas lab. The time between specimen collection and analysis should not exceed 30 minutes.
  • Syringes with needles attached will NOT be accepted.
  • Blood Gas syringes may be obtained from Central Distribution.
  • Do not separate or freeze whole blood. 

Reviewed by J. Carr on January 15, 2026

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514