Factor V Activity
Also known as: Proaccelerin
Use
Evaluate an isolated prolonged PT or for evaluation when both the aPTT and PT are prolonged and to assess factor V activity level.6-8
Special Instructions
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. Ideally, the patient should not be on anticoagulant therapy. Avoid warfarin therapy for two weeks prior to the test and heparin, direct Xa, and thrombin inhibitor therapies for about three days prior to testing. Do not draw from an arm with a heparin lock or heparinized catheter.
Limitations
This test cannot diagnose factor V Leiden mutation. Direct Xa or thrombin inhibitor therapy may cause factitiously low results. The presence of specific factor V inhibitors, especially after surgical procedures involving bovine thrombin, may also affect the results. Elevated factor V activity has been associated with an increased risk for myocardial infarction, though not recommended for thrombotic risk assessment by diagnostic consensus bodies.
Methodology
Culture-based
Biomarkers
LOINC Codes
- 3193-0
- 3193-0
Result Turnaround Time
2-3 days
Related Documents
For more information, please review the documents below
Specimen
Plasma
Volume
1 mL
Minimum Volume
Not provided
Container
Blue-top (sodium citrate) tube
Collection Instructions
Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes 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. Avoid collecting from an arm with a heparin lock or catheter.
Patient Preparation
Ideally the patient should not be on anticoagulant therapy. Avoid warfarin therapy for two weeks prior to the test and heparin, direct Xa, and thrombin inhibitor therapies for about three days prior to testing.
Storage Instructions
Freeze.
Causes for Rejection
Severe hemolysis; improper labeling; clotted specimen; specimen diluted with IV fluids; samples thawed in transit; improper sample type; sample out of stability
Stability Requirements
| Temperature | Period |
|---|---|
| Frozen | 28 days |
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