Laboratory: Clinical Biochemistry
Test Name:
CALCIUM, IONIZED - (S)
Test Code: ICA
Clinical Information:
If a tourniquet is used, it must be left on until all the required blood is drawn (but no longer than 3 minutes), and patient should not be allowed to exercise the forearm.
The patient must avoid strenuous activity immediately before phelbotomy. Avoid fist clenching during phelbotomy.   
Second order test used to assess calcium status in patients with abnormal albumin and serum protein concentrations or in the presence of molecules that may influence free calcium concentration (e.g. citrate, increased lactate, altered pH, etc)
Collection Devices:
Preferred Devices:
1 - Microtainer(s) - Serum Separator (0.6mL)  - Pediatric microtainer must be full.  Transport to lab immediately.
- And -
1 - Serum Separator (SST) Tube(s) - Full Tube Collection  - SST: Tube must be full and unopened.
Microtainer: Must be full and transported to the lab immediately.
Specimen Required:


Serum: 2.0 mL
Pediatric Serum: 0.3 mL

Adult: FULL draw, unopened SST tube
Pediatric: FULL draw, unopened SST microtainer tube
Collection Information: PARTIAL draw tubes are not acceptable for ionized calcium testing
Referral:

Adult Volume: FULL draw, unopened SST tube
Pediatric Volume: FULL draw, unopened SST microtainer tube
Requisition:
Reference Values:
1 - 3 d: 1.07-1.35  mmol/L                   
4 d: 1.12-1.48
5 d: 1.23-1.49
6 d: 1.25-1.51
7 d: 1.22-1.56
8 d: 1.30-1.52
9 d - 12 mo: 1.23-1.41
Male 1 - 20 y: 1.23-1.38
Female 1 - 18 y: 1.23-1.38
Adult: 1.17-1.32
Availability:
Stat or Routine
See Also:
More Information:
Centrifuge samples within 2 hours of collection. Do not remove stopper. If sample cannot be analyzed immediately, it can be stored anaerobically at 4 C for up to 48 hours.
Samples in microtainers should be analyzed immediately
Micro collection procedure:
a) Warm foot. b) Perform skin puncture. c) Keeping foot lower than the heart, and with minimal squeezing, fill microtainer completely, cap and transport to lab without delay.  Analyze immediately.