von Willebrand Profile (vWF Ag and vWF activity), Ref Lab
Alternate Names
084715 LC
SoftLab Order Code
VWP
Epic Order Name
VON WILLEBRAND PROFILE (VWF AG AND VWF ACTIVITY), REF LAB LC 084715
Epic Order ID
LAB1112
Tests Included
Factor VIII; von Willebrand factor activity; von Willebrand factor antigen
Laboratory
Reference Lab
Additional Test Information
If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted.
Sample Type
Plasma
Collection Container
Blue Top (Sodium Citrate - Light blue)
Collecting Volume
3 full light blue top tube
Minimum Collecting Volume
2 full light blue top tube
Storage or Stability
Frozen
Causes for Rejection
Gross hemolysis; clotted specimen; frozen specimen thawed in transit
Patient Preparation
As VWF and FVIII are acute-phase reactant proteins, patients should be at ease when blood is drawn. Undue stress, such as a crying child or very recent exercise may elevate VWF levels, and these conditions should be avoided.
Instructions
Citrated plasma samples should be collected by double centrifugation. Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.Evacuated collection tubes must be filled to completion to ensure a proper ratio