Factor X Activity (F10)
Department: Coagulation
Test Synonym(s): LAB758, F10, Factor 10 Activity
CPT Codes: 85260
Methodology: Clotting
Reference Range: 50 - 150%
Tube Type: One 2.7mL Light blue top - 3.2% Sodium Citrate
Specimen: Citrated platelet poor plasma - Requires double centrifugation if sending a plasma aliquot. Aliquot(s) must be frozen if not received by lab within 4 hours of collection.
Alternate Specimen: None
Pediatric Requirements: Pediatric: One 2.7mL Light blue top - 3.2% Sodium Citrate. Neonatal: One 1.8mL Light blue top - 3.2% Sodium Citrate.
Volume: 1.0 mL plasma
Minimum Volume: 1.0 mL plasma
Temperature: Room Temperature for Light blue top tube, must be received within 4 hours of draw. Plasma aliquot(s) must be frozen if not received by lab within 4 hours of collection.
Stability: Room temperature: 4 hours, Frozen: -70 C for one month
Reasons for Rejection: Clotted sample, incorrectly filled tubes, incorrect tube type, grossly hemolyzed sample, grossly lipemic sample, grossly icteric sample, whole blood >4.0 hours old
Days Performed: Monday - Friday
Times Performed: 8:00 AM. - 2:00 PM. After hours testing must be approved by the director or Pathology resident on call.
TAT: 1 - 3 days
Significance: CANNOT be used to monitor Heparin therapy. See Heparin assays - unfractionated or low molecular weight. Unexpected result may be obtained on samples from patients taking Warfarin drugs. Direct Thrombin inhibitors and both Direct and Indirect Xa inhibitor
Special Instructions: The Factor X Activity test is not a test for Unfractionated Heparin or Low Molecular Weight Heparin. It should not be used for monitoring direct factor Xa Inhibitors (Rivaroxaban, Apixaban, Edoxaban). Tubes must be filled to indicator line and not clotted. Indwelling lines should be flushed with saline only and 5 mL of blood should be discarded prior to collecting samples for coagulation studies. If sending plasma aliquots, DOUBLE CENTRIFUGE plasma samples to produce platelet poor plasma. Samples received from an outside lab must be aliquoted and frozen. Grossly hemolyzed, icteric or lipemic samples may be rejected. Ordering physician name and telephone contact information MUST accompany the sample and request. Vanderbilt Esoteric Coagulation Laboratory: 615 875-5633
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