Label Mnemonic: MG
Epic Lab Code: LAB103
Downtime Form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
6240 RCP
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
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
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.
Colorimetric endpoint
CPT Code:
See also:
Magnesium-Other, Body Fluid
See Additional Information:
Chemistry Critical Lab Values