Yale New Haven Hospital

Department of Laboratory Medicine
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Factor VIII assay

Lab Section: 

Coagulation

 

Lab Location: 

Main Lab

Test ID: 

LAB306

 

Synonyms:

FVIII

 

Methodology: 

Clotting

Schedule: 

Mon-Fri

Reported: 

3 - 5 days

Specimen Requirements: 

Collection: 2.7 mL Blood in a Blue Top Tube.
Pediatric volume: 2.7 mL.
Tubes must be full.
Transport: Whole blood may be transported at ambient or refrigerated temperature. Separated plasma, not yet frozen, may be transported at refrigerated temperature, while frozen plasma should be sent on dry ice to prevent thawing in transit.
Unacceptable conditions: QNS; Overfilled; Clotted

 

Notes: 

Reflex Criteria: FVIII assay auto reflex to PTT. Abnormal results reflex to an MD interpretation.

Clinical Indications: Unexplained prolongation of PTT in the investigation of bleeding tendency; familial history of Factor VIII deficiency. Evaluation of thrombosis risk.

Three (3) clotting factor assays may be performed from one full 2.7-mL tube. If additional clotting factor assays are needed, additional tubes are necessary.

Reference Interval: 

Age Limit

Sex

Normal Range

Units

0 Days - 999 Years

Any

50-200

%

 

CPT Code(s): 

85240

Last Changed: 

8/16/2017 1:17 PM

Last Reviewed: 

8/16/2017 1:17 PM