1 x plain (red) sample must be kept anaerobic. Transport on ice to laboratory
Registration
Send sample on ice to separating
Synonyms
calcium, ionised
iCa, serum
Turnaround Time
2 hours
Test Code
4209
Specimen Type
Serum
Specimen Requirements
Tube/Container Type:
Preferred
Serum (Red Cap)
Preferred Sample Volume (ml)
4.0
Pre-testing Requirements
Forearm exercise with the tourniquet in place and removal of the tourniquet before the collection device is full will significantly affect iCa results.
Gross haemolysis has been reported to clinically significantly lower the iCa result
Benzalkonium heparin (may be used in arterial catheters) can elevate the results by up to 0.6 mmol/L.
Additional Specimen Information
Serum should be aliquotted into a syringe (Veterinary only: or microtainer). Minimise contact with air. Send to laboratory ASAP
Aliquot Instructions
Minimum Volume (ml)
1.0
Reference Intervals
0 day – 1 year: 1.15-1.45 mmol/L
>1 year: 1.15-1.30 mmol/L
Test Method
Radiometer ABL 90 Flex
Non-Funded Test Cost
$28.50 (Exclusive of GST)
Billing Code
3002
Ionised Calcium replaces ultrafiltrable calcium which is no longer offered.
Please note change to reference interval from 16 January 2026.
