Factor 7 activity

Alphabetical Test listing

Factor 7 activity-994

  
Factor 7 activity
  
994
  
LAB994
  
MSO
  
Factor VII activity
Proconvertin
  

Evaluate an isolated prolonged PT and document factor VII deficiency

  

Direct Xa or thrombin inhibitor therapy may cause factitiously low results.

  
  • Ideally, the patient should not be on anticoagulant therapy
  • Avoid warfarin (Coumadin®) therapy for two weeks prior to the test and heparin, direct Xa, and thrombin inhibitor therapies for about three days prior to testing
  
Sodium citrate (Na cit) plasma
  
  
1.0 mL
  
  • If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted.
  • Do not draw from an arm with a heparin lock or heparinized catheter
  • 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 to ensure adequate mixing of the anticoagulant with the blood.
  • A discard tube is not required prior to collection of coagulation samples unless the sample is collected using a winged (butterfly) collection system.
    • With a winged blood collection set a discard tube should be drawn first to account for the dead space of the tubing and prevent under-filling of the evacuated tube.
  • 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 alternative 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.

 

  
  1. Spin
  2. Transfer 1.0 mL plasma to a Screw-cap polypropylene frozen transport vial/tube - 4mL (LabCorp), labelled as Na cit plasma
  3. Freeze
  

Frozen - 28 days

Freeze/thaw cycles - stable x3

  
  • Gross hemolysis
  • Clotted specimens
  • Specimens that have thawed in transit
  • Improperly labeled specimens
  
LabCorp Burlington (800599): R-NX
  
Daily
  
4 days
  

Prothrombin Time (PT)-based one-stage clotting time assay. Factor VII- depleted plasma is used as the substrate and the substrate and the clotting time with the patient plasma is compared to the clotting time of normal pooled plasma.

  

51 - 186%

Direct Xa or thrombin inhibitor therapy may cause factitiously low results.

  
85230
  
Result 3198-9
  
05/29/2019
  
05/31/2024
  
04/06/2022