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von Willebrand Panel
|Test group||von Willebrand|
|Performed by||Parnassus Hematology|
|Collection Instructions||1. Check the expiration date on the label of the blue top vacutainer before drawing the patient.
2. For blood collection in a sodium citrate blue top, the tube must be filled to above the Minimum Fill Indicator on the tube. It is crucial to wait and allow the tube to stop filling before removing it from the needle.
3. With use of a butterfly needle, draw about 1 cc using a separate blue top to remove air from tubing, discard the first tube and then draw a second blue top tube filled to the full extent of the vacuum.
4. Tubes should not be filled past the Maximum Fill dashed line by either using a syringe or removing the tube cap.
For patients with Hct's ≥ 55% please contact Hematology (415-353-1747) to obtain blue top tubes with adjusted citrate volumes in order to maintain the proper citrate to plasma ratio for coagulation studies.
|Container type||Blue top filled to full extent of vacuum x2|
|Amount to Collect||5.4 mL blood|
|Sample type||Citrated plasma|
|Preferred volume||2 mL plasma|
|UCSF Rejection Criteria||Samples collected in outdated blue top vacutainer. Over-filled or under-filled tubes may be rejected|
|Processing notes||Freeze plasma in plastic at -20C.
Contains test codes: F8,VWFAG, RCOF
|Turn around times||Test run q1-2 weeks. Turnaround time: 1-4 weeks.|
|Additional information||This panel includes Factor VIII Activity, Ristocetin Cofactor, and Von Willebrand Factor Antigen. For additional information, see entries for individual panel members.|
|Last Updated||9/18/2012 2:32:29 PM|
If you have additional questions regarding this test, please call: 415-353-1667