VON WILLEBRAND SCREEN WITHOUT PLATELET AGGREGATION STUDIES

Additional Codes

Software	Code
SOFTID	VWSCR
EPIC	LAB20047

Performing Laboratory

NorDx Laboratories

Useful For

Detecting deficiency or abnormality of von Willebrand factor and related deficiency of factor VIII coagulant activity

Tests may be ordered individually.

Method Name

Clot-Based Assay

Latex Immunoturbidometric Assay

Platelet Agglutination

Reference Values

An interpretive report will be issued

Days and Times Test Performed

Monday or Friday

Report Available

14-21 Days

Specimen Type

Plasma

Preferred Container

Light Blue Top Tube (Sodium Citrate) – Collect 3 Tubes. Tubes must be full at time of collection, short draws will be rejected.

Specimen Collection and Handling

Collect specimen as follows:

1. Draw blood in light blue-top (3.2% sodium citrate) tube(s). Tube(s) must be full upon collection.

2. Separate plasma from cells as soon as possible within 4 hours of collection in a centrifuge at 2,500 rpm for 15 minutes or 3,000 rpm for 10 minutes.

3. Using a plastic transfer pipette (do not use a glass pipette) decant the plasma to a screw-capped, plastic (polypropylene) vial. Glass vials will not be accepted.

4. Spin the plasma again at 2,500 rpm for 15 minutes or 3,000 rpm for 10 minutes. Note: Double spinning the specimen ensures platelet poor plasma (<10,000 uL)

5. Divide the plasma into as many 0.5-1.0 mL aliquots as possible and cap the vial(s) tightly.

6. Place tubes upright and flash freeze specimen(s) immediately at ≤ – 20° C or below.

7. Send specimen(s) FROZEN on dry ice.

Click here to view the Procedure for Collecting a Specimen from an A-line

Specimen Stability Information

Specimen Type: Plasma

Frozen: 1 Month

Room Temp: 4 Hours

Note: Whole blood that remains capped and unspun is stable for up to 4 hours when stored at room temperature (18 – 24°C). Frozen plasma is stable 2 weeks @ -20°C and 12 months @ -70°C. Blue top tubes for coag assays must not be refrigerated or placed on ice.

Add On Capable

Not Permitted

Advance Beneficiary Notice Requirements

No ABN Required

CPT Code Information

CPT Code	CPT Description	CPT Disclaimer
85240	Clotting, Factor VIII (AHG), 1-stage
85245	Clotting, Factor VIII von Willebrand (VW) Factor, Ristocetin Cofactor
85246	Clotting, Factor VIII von Willebrand (VW), Factor Antigen

Performing Laboratory Location