Magnesium

Label Mnemonic:	MG
Epic code:	LAB103
Downtime form:	Doctor/Provider Orders - Pathology Core and Specialty Care Nursery

Chemistry
6240 RCP
356-3527

Specimen(s):

Plasma

Collection Medium:

Plasma Separator Tube 4.5 mL

Alternate Collection Media:

Call laboratory for additional acceptable specimen collection containers.

Minimum:

3 mL whole blood in light green top tube or ONE Microtainer^® for pediatric patients.

Rejection Criteria:

Avoid hemolysis

Testing Schedule:

24 hrs/day, 7 days a week, including holidays.

Turn Around Time:

1 hour (upon receipt in laboratory)

Reference Range:

1.5-2.9 mg/dL

Critical value: <1.0 mg/dL and >4.7 mg/dL

Comments:

Refer to BD Microtainer^® Tubes product sheet for detailed sample collection instructions.

This test is also performed in the Iowa River Landing (IRL) clinical laboratory (for specimens drawn at that site).

Test Limitations:

Criterion: Recovery within plus or minus 10% of initial values.

Plasma
Icterus: No significant interference up to an I index of 60. 

Hemolysis: No significant interference up to a H index of 800. 

Lipemia (Intralipid): No significant interference up to an L index of 
2000 (approximate triglycerides concentration: 4000 mg/dL). There is 
poor correlation between turbidity and triglycerides concentration. 

In-vitro tests were performed on 34 commonly used pharmaceuticals. 

No interference with the assay was found.

Reference:
Glick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences 
in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-474.

Methodology:

Colorimetric endpoint

CPT Code:

83735

See Additional Information:
Chemistry Critical Lab Values