PTT Mixing Study

YPTTMR

PTT Mixing Study

Sodium Citrate

One sodium citrate (light-blue top) tube (Must be received at lab within 4 hours) OR Two 0.5 mL aliquots of platelet poor citrated plasma, Frozen

Collect specimen and mix immediately after filling with blood. Tubes MUST be full. DO NOT overfill or underfill. Gently mix tube by inverting 5 to 6 times. Vigorous mixing or shaking may cause hemolysis, which will affect the result.
To prepare platelet poor plasma: Centrifuge, and then using a plastic disposable pipette, carefully transfer the top ¾ of the plasma into a transfer tube, avoiding the buffy coat. DO NOT pour off. Freeze immediately.

Specimens collected in an anticoagulant other than 3.2% sodium citrate
Under or overfilled specimens
Clotted specimens
Grossly hemolyzed, lipemic, or icteric specimens
Refrigerated or frozen whole blood specimens

Room temperature 4 hours - specimens with Unfractionated Heparin testing must be centrifuged within 1 hour. Frozen 2 weeks If specimen cannot be tested within 4 hours, prepare platelet poor citrated plasma and freeze plasma in two 0.5 mL aliquots