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Factor XI, Activity

Mnemonic:    [FactXI Act]
Name:    Factor XI, Activity
Specimen:    2 mL plasma from a FULL sodium citrate Blue top tube. Allow tube to fill to proper capacity. Mix immediately by gentle inversion 4 times.
The sample must be centrifuged immediately in a precalibrated, authorized centrifuge. The sample must be doubly spun to insure that it is platelet poor plasma. We recommend that patients be sent to the outpatient phlebotomy lab, so the samples can be processed appropriately.

Hemolyzed specimens are not acceptable.
Minimum Spec:    1 mL
Neonatal Spec:    1 Ml
Transport Temp:    Critical Frozen sample. Freeze immediately and transport frozen.
Spec Stability:    Stable 2 weeks frozen.
Ref Lab/Code:    ARUP 0030110
  Method:    Clotting
Processing Info:    Give samples to coagulation tech to be spun in the calibrated centrifuge.

Each coagulation test sample must be separately frozen. Send separate specimens when multiple tests are ordered.