Fibrinogen Activity

Message

If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted. Refer to Coagulation Collection Procedures for directions.

Test Code

001610

Alias/See Also

Clottable Fibrinogen; Factor I Activity

CPT Codes
85384

Preferred Specimen

Whole blood or plasma

Minimum Volume

90% of full draw

Instructions

Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate.(1) Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio.(2,3) 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.(4,5) 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 alternate 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. To avoid delays in turnaround time when requesting multiple tests on frozen samples, please submit separate frozen specimens for each test requested. If testing cannot be completed within 24 hours, specimens should be centrifuged for at least 10 minutes at 1500xg. Plasma should then be transferred to a LabCorp PP transpak frozen purple tube with screw cap (LabCorp No 49482). Freeze immediately and maintain frozen until tested. Refer to Coagulation Collection Procedures for directions. Please print and use the Volume Guide for Coagulation Testing to ensure proper draw volume.

Transport Container

Blue-top (sodium citrate) tube; do NOT open tube.

Transport Temperature

Specimens are stable at room temperature for up to 24 hours. If testing cannot be completed within 24 hours, specimens should be centrifuged for at least 10 minutes at 1500xg. Plasma should then be transferred to a LabCorp PP transpak frozen purple tube w

Specimen Stability

1 day at room temp; frozen plasma 14 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Clotted specimen; gross lipemia or hemolysis; tube <90% full; improper labeling; specimen collected in tube other than 3.2% citrate

Methodology
The measurement of fibrinogen activity is based on determination of fibrin polymerization function by the Clauss method.(11) This method measures the rate of clot formation after adding a high concentration of thrombin to citrated plasma. The fibrinogen a

Setup Schedule

Daily 1st shift

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.