Protein C activity

Alphabetical Test listing

Protein C activity-5756

Protein C activity
Protein C functional

Patient cannot be on Coumadin, Lepirudin, or Argatroban

Sodium citrate (Na cit) plasma
1.5 mL
  • Patients on Heparin must be drawn just prior to next dose; do not draw immediately after dose.
  • Sample may be drawn 5 days after coumadin has been stopped or 48 hours after Vit K administration.
  • Do not over or under fill tube as the ratio of anticoagulant to whole blood is critical

Coag – tube fill guidelines

  • If the patient has a hematocrit >55, a specially prepared Lt blue Sodium citrate (NaCit) tube must be used in place of the standard Lt blue Sodium citrate (NaCit) tube.

Hematocrit-Anticoagulant adjustments

  • Immediately following collection, mix sample thoroughly by gently inverting 8 - 10 times to prevent clotting

Microcentrifuge vial/tube in a Snap cap conical vial/tube and cap (Beaker sites)



Coagulation specimen transport vial/tube  (all other sites)




Frozen (strict)

Refrigerated - NO

  • Specimens collected in Greiner tubes
  • Improper labeling (unlabeled or mislabeled)
  • Improper anticoagulant
  • Improperly filled tube
  • Hemolysis
  • Clotted specimen
  • Delay in transport
  • Improper storage/transport temperature
  • Patient on heparin > 1.0 IU/mL
AHL - Coagulation/Special Coagulation: V
Varies: 1 - 2 times/wk
Available STAT
3 - 5 days

Chromogenic assay


70 - 150%