Days Set Up
Daily, 24 hours for UMHS inpatients, Emergency Department patients, and Veterans Hospital patients. Monday-Friday, 1 run per day for MLabs and outpatients.
Analytic Time

2 hours

MiChart Code
Factor 8 Assay
Soft Order Code
F8

Test Updated:

Synonyms

Coagulation Factor VIII Assay
Factor 8 Activity
Factor VIII Assay
Factor VIII:C Assay
F8

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Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

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Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

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Test Overview

Test Methodology

Photo-optical clot determination with Factor VIII deficient substrate.

Test Usage

Detection of specific coagulation factor VIII deficiency

Reference Range

50-150%

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Specimen Requirements

Collection Onsite

Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.

Collection Offsite

Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a polypropylene plastic vial, and freeze the specimen within 4 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.

Blue Top Tube
Normal Volume
Full 2.7mL tube or 1mL plasma aliquot
Minimum Volume
Full 1.8mL tube or 1mL plasma aliquot

Billing Information

CPT Code
85240
Pro Fee Code
 
LOINC
3209-4

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.