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Jun 24, 2016

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Clinical Hub,Tools & Resources,UWHC Lab Test Directory,Coagulation

Factor VIII Activity

Factor VIII Activity (HCF8A) Coagulation Lab Test

Name: Factor VIII Activity

Test Name: Factor VIII Activity

Health Link Test Code: HCF8A

LIS Test Code: F8A

CPT Code(s): 85240

Included In: May be included in von Willebrand Disease workup.

Methodology: Photo-Optical Clot Detection

Clinical Information:

Assay used to assess activity of Factor VIII when clotting abnormality is suspected.

Days Performed: Mon-Fri, dayshift - day varies. Specimens are accepted at any time. Testing required during off hours must be approved by a Coagulation physician. Call 263-5005 before collection.

In-Lab Turnaround Time: 4 - 10 days.

Stat In-Lab Turnaround Time: 1 day.

Specimen: Blood

Collection Container: Light blue top (3.2% NaCitrate)

Collection Instructions:

Do NOT draw through a line containing heparin. The venipuncture MUST be atraumatic to avoid hemolysis and contamination with tissue factors and platelets. Tube must be allowed to fill completely.

 

Indicate if patient is receiving anticoagulant (warfarin/Heparin/Vitamin K antagonist), direct thrombin inhibitor or fibrinolytic agent therapy and duration.

 

If unable to collect 1.8 ml tube (pediatrics only) please call UWHC Coagulation Lab at (608) 263-9617 or UWHC Special Coagulation Lab at (608) 263-5005 for alternate tube and instructions.

Collection Volume: Full 3.5 mL tube

Pediatric Collection Volume: Pediatric tube filled to fill mark

Stability Ambient:

4 hours on a spun tube

Stability Refridgerated:

Not acceptable

Stability Frozen:

2 weeks at -20°C; 6 months at -70°C

Sample Analyzed: Plasma

Testing Volume: 1 mL

Pediatric Testing Volume: 1 mL

Specimen Processing:

Centrifuge specimen to yield platelet poor plasma (platelet count should be less than 10 K/µL). Separate plasma and transfer to plastic tube or vial. Freeze plasma within 4 hours of collection at -20°C or below.

Outreach Specimen Processing:

Centrifuge specimen to yield platelet poor plasma (platelet count should be 10 K/µL or less). Separate plasma and transfer to labeled plastic tube and spin again. Transfer plasma from second spin to clean plastic labeled tube or vial. Indicate on tube "spun twice". Freeze plasma within 4 hours of collection at -20°C or below.

Specimen Transport:

Transport whole blood specimen at room temperature to UWHC Hospital Laboratory within 4 hours of collection. See Specimen Processing for instructions if transport criteria are not met. Transport frozen plasma aliquot on dry ice to UWHC Hospital Laboratory.

Unacceptable Criteria:

Hemolyzed specimens, clotted specimens, partially filled tubes and whole blood specimens greater than 4 hours old when received by the laboratory are not acceptable.

Interpretation:

 0 days and up:  60.0-180.0% NPP

Interpretation Type: Reference Interval