FACTOR XII
Coagulation Factor XII (12) Activity
EPIC Test Procedure Code: LAB5180
Performing Lab:
Referral Laboratory
Patient Preparation:
Avoid warfarin (Coumadin(R)) therapy for 2 weeks and heparin therapy for 2 days prior to the test. Do NOT draw from an arm with a heparin lock or heparinized catheter.
Container Type:
Light blue top (sodium citrate) tube
Specimen Type:
Plasma
Preferred Volume:
1 mL
Collection Procedure:
The blue top tube must be filled to completion to ensure a proper blood-to-anticoagulant ratio. The sample should be mixed immediately by gentle inversion at least six times to ensure adequate mixing of the anticoagulant with the blood.
Store and Transport:
Frozen
Stability:
Frozen: 28 days (Freeze/thaw cycles: stable x3)
Unacceptable Condition:
Severe hemolysis; improper labeling; clotted specimen; specimen diluted with I.V. fluids; samples thawed in transit; improper sample type; sample out of stability.
CPT Codes:
85280 - Factor XII Activity (EAP 30520785)
Method:
Factor XII activity is determined utilizing an aPTT-based one-stage clotting time assay. Factor XII-depleted plasma is used as the substrate and the clotting time with the patient plasma is compared to the clotting time of normal pooled plasma.