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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Calcium, Ionized

Test Code(s): ICA / XICAL

CPT Code(s): 82330

Methodology: Ion Selective Electrode

Days Performed: Daily, 24 hours.

Turnaround Time: Stat: 1 hour. All requests processed stat.

Specimen Requirements

Specimen: Blood

Collection Instructions: Draw without tourniquet if possible. Tube MUST be allowed to fill completely.  For faster turnaround, see Calcium, Ionized, Whole Blood.

Collection Container: Preferred: Red cap with yellow ring (SST)
Also Acceptable: Red top

Collection Volume: Preferred: Full 4 mL tube
Pediatrics: Full 2 mL tube

Sample Analyzed: Serum

Volume Required: Preferred: 4 mL
Pediatrics: 2 mL

Specimen Processing: Centrifuge to form a complete barrier.

Specimen Transport: Transport specimen to laboratory immediately.

Outreach Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220) with coolant pack if coming from outreach location.

Unacceptable Criteria: Green top tubes are not acceptable.  Microtainer tubes are not acceptable.

Stability: Ambient: Unopened, uncentrifuged- 2 hours; Unopened, centrifuged- 4 hours
Refrigerated: Unopened, centrifuged- 4 days


Reference Interval:
 Age 1 month and up:  
 Actual ICA   4.60-5.20 mg/dL

 Calculated ICA corrected to pH 7.4

 4.70-5.25 mg/dL


Test Limitations:

Add-on requests for serum ionized calciums will not be accepted if sample has been previously opened and exposed to air. The alternative will be to add a whole blood ionized calcium (WBICA) to a blood gas previously drawn and sent to lab.

Critical Calls: View

Ionized Calcium

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