Specimen Collection Manual and Test Catalog
FIBRINOGEN
Geisinger Epic Procedure Code: LAB2283 Geisinger Epic ID: 7170Platelet-poor plasma
1 mL
- If the patient’s hematocrit (HCT) is >55%, the volume of anticoagulant in the tube must be adjusted. Contact a performing location for sodium citrate adjusted tubes or instruction for how to adjust the sodium citrate.
- When possible, use fresh venipuncture.
- Avoid prolong tourniquet time (< 1 minute) and hemolysis during collection as this will alter results.
- If indwelling catheter or butterfly collection device must be used, draw sample from a non-heparinized lumen or flush the line with 5 mL of saline and discard the first 10 mL of blood.
- Tubes should be >90% filled.
- Immediately mix gently after collection by inverting the tube end over end 5 to 6 times. Avoid vigorous mixing or additional inversion. Observe for the presence of clots or hemolysis and recollect if observed.
Centrifuge specimen immediately at designated time and speed to obtain platelet-poor plasma (<10,000/µL). Using a plastic pipette, carefully remove plasma from cells, avoiding platelet/buffy layer by leaving a thin layer of plasma on top the cells. The centrifuged plasma should be aliquoted (1 mL per aliquot) into clearly labeled polypropylene tubes. The number of tests ordered will determine the aliquots needed. Check the residual specimen for clot and if present discard sample and redraw specimen. If plasma is icteric, lipemic or hemolyzed a lab comment should be generated to notify staff. Freeze upright in non-thaw freezer.
Plasma (on or off packed cells): Room temperature
Plasma off cells: Frozen on dry ice
Room temperature (plasma on cells): 4 hours
Room temperature (plasma off cells): 8 hours
Frozen (plasma) -20°C: 2 weeks
Frozen (plasma) -70°C: 6 months
Clotted, hemolyzed, improperly filled tubes, improper anticoagulant ratio (HCT >55% and citrate not adjusted), refrigerated specimens, or stability exceeded.
Note: Specimen suspected of thawing in transport, indicated by slant in aliquot or specimen in lid of tube, will have testing performed, and the comment “interpret results with caution as thawing suspected” added to results.
178-467 mg/dL
The CPT codes provided by GML are based on AMA guidelines and are for informational purposes only.
Fibrinogen activity
Thrombin Clotting Rate Assay
Factor I
A soluble plasma protein that is converted by thrombin to form an insoluble fibrin clot. It also plays a role in platelet activation and aggregation.
Hypofibrinogenemia, or low fibrinogen levels, may be congenital or acquired from bleeding, disseminated intravascular coagulopathy (DIC) or severe liver disease. Levels may be elevated in chronic inflammation, pregnancy, or early/moderate liver disease. Dysfibrinogenemia, or an abnormal fibrinogen protein, may result in bleeding or thrombosis. Dysfibrinogenemia may result in low levels using this methodology, therefore, if suspected recommend comparing results to a fibrinogen antigen level. In patients with dysfibrinogenemia the fibrinogen activity and fibrinogen antigen levels will be different.