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von Willebrand Panel w/reflex to vW Multimeric Analysis

Mnemonic:    [VW Pan R]
Name:    von Willebrand Panel w/reflex to vW Multimeric Analysis
Specimen:    5 mL plasma from a FULL sodium citrate Blue top tube. Allow tube to fill to proper capacity. Mix immediately by gentle inversion 4 times. Collect 2 full 4.5 mL blue tops.

The sample must be centrifuged immediately in a precalibrated, authorized centrifuge. The sample must be doubly spun to insure that it is platelet poor plasma. We recommend that patients be sent to the outpatient phlebotomy lab, so the samples can be processed appropriately.

Unacceptable Conditions: Serum. Specimens collected in wrong anticoagulant. Clotted, hemolyzed, or non-frozen specimens.
Minimum Spec:    2 mL
Transport Temp:    FREEZE
Spec Stability:    Stable 4 hours ambient.
Ref Lab/Code:    ARUP 2003387
Note:    Panel includes:
-- Factor VIII Activity
-- von Willebrand Factor Antigen (vWF Ag)
-- von Willebrand Factor Activity (Ristocetin Cofactor or RCF)

If the Ristocetin Cofactor, vW Factor Antigen or Factor VIII Activity is low the vW Multimeric Analysis will be added.

In addition if the RCF/vWF Ag ratio is <0.7, the von Willebrand Multimeric Analysis will be added.
Processing Info:    Take the tubes to Coagulation for processing.

Separate sample must be submitted when multiple tests are ordered.