von Willebrand Diagnostic Panel that includes Multimers : 1004029

The aliquots must remain frozen. Freeze thaw cycle will adversely affect specimen integrity. CRITICAL FROZEN: Separate specimens must be submitted when multiple tests are ordered.

Test Code

CPT Codes
85246, 85245 85240, 85730, 85247

This test includes the following individual tests:

Test Name                                                                                                                                                                               Order code             Interface code
Von Willebrand Diagnostic Panel with Interpretation                                                                                                                     VWPI                      1004028      
(VWPI includes von Willebrand Factor Ag, Ristocetin Cofactor Activity, Factor VIII Activity, Activated Partial Thromboplastin Time)                   
von Willebrand Antigen Multimeric Analysis                                                                                                                                  VWAGQ                   5168

Blue top tube, 3.2% sodium citrate.
• Obtain venous blood by clean venipuncture. Avoid slow-flowing draws and/or traumatic venipunctures as either of these may result in an activated or clotted specimen. Do not use needles smaller than 23 gauge. Do not leave the tourniquet on for an extended length of time before drawing the sample.
• A pilot tube (non-additive or light blue tube) before drawing coagulation specimens in light blue vacuum tubes is only necessary when using a butterfly blood collection set as this will cause reduced draw volume in the first tube. Discard the pilot tube.
• Fill light blue tubes as far as vacuum will allow and mix by gentle inversion. Exact ratio of nine parts blood to one part anticoagulant must be maintained. Inadequate filling of the sample tube will alter this ratio and may lead to inaccurate results. Patients who have hematocrit values above 55 percent should have the anticoagulant adjusted to maintain the 9:1 ratio. Use the following formula to determine the amount of anticoagulant to use: [(100 – Hct) / (595 – Hct) ]* total volume = amount of anticoagulant required.
• After collecting the blood, examine the tube to ensure that it is filled to within 90% of the fill line.
• Note: Specimens containing heparin should not be used for coagulation studies. If possible, stop heparin therapy before the draw to avoid contamination. Heparin interferes with most clotting assays. If heparinized line must be used to obtain the sample, flush line with 5mL saline and discard the first 5 mL of blood drawn into a syringe, or 6 “dead space” volumes of the line.

Transport Container
Centrifuge the blue top tube at a rate of speed to yield platelet poor plasma (<10,000 /uL), immediately remove only the top two-thirds of the platelet-poor plasma from the specimen using a plastic-transfer pipet (use of glass-transfer pipets may result in activation and/or clotting of the plasma) and split the citrated plasma (Min. 2.5 mL) into three standard transport tubes, and freeze the three aliquots.

Transport Temperature

Specimen Stability
Refer to Individual Test Codes.

Refer to Individual Test Codes.

Setup Schedule
Refer to Individual Test Codes.

Report Available
Refer to Individual Test Codes.

Reference Range
Refer to Individual Test Codes.

Performing Laboratory
med fusion and Quest Diagnostics

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.