Lt blue Sodium citrate (NaCit) - 2.7mL x 2

• 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
• If the patient's hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted

1. Centrifuge for 10 minutes and carefully remove 2/3 of the plasma using a plastic transfer pipette, being careful not to disturb the cells.
2. Deliver to a plastic transport tube, cap, and recentifuge for 10 minutes.
3. Use a second plastic pipette to remove plasma, staying clear of the platelets at the bottom of the tube.
4. Transfer the plasma into a Screw-cap polypropylene frozen transport vial/tube - 4mL (LabCorp), labelled as Na cit plasma
5. Freeze immediately.

Screw-cap polypropylene frozen transport vial/tube - 4mL (LabCorp)

Frozen (preferred)

Freeze/thaw cycles - stable x4

Refrigerated - 24 hours

Ambient - 8 hours

PTT assay

60 - 150%