von Willebrand Factor (vWF) Multimers

11 days

The Sebia Hydragel™

This test includes von Willebrand factor activity, von Willebrand factor antigen, VWF:Ag/ VWF:Ac ratio; and von Willebrand Multimer results including percent Intermediate and High Molecular Weight Fractions.

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This test is used to measure the relative levels of von Willebrand low molecular weight multimers (LMWM), intermediate molecular weight multimers (IMWM) and high molecular weight multimers (HMWM) in plasma.

Plasma, frozen

2 mL

Blue stopper 3.2% sodium citrate plasma evacuated tube

No special preparation is required for this test. You may eat, drink, and take your medications as normal, unless instructed otherwise by your healthcare provider.

Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.24 Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio.25,26 The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood. A discard tube is not required prior to collection of coagulation samples unless the sample is collected using a winged (butterfly) collection system. With a winged blood collection set, a discard tube should be drawn first to account for the dead space of the tubing and prevent under-filling of the evacuated tube.27,28 When noncitrate tubes are collected for other tests, collect sterile and nonadditive (red-top) tubes prior to citrate (blue-top) tubes. Any tube containing an alternative anticoagulant should be collected after the blue-top tube. Gel-barrier tubes and serum tubes with clot initiators should also be collected after the citrate tubes.