Referral Laboratory

Avoid warfarin therapy for 2 weeks and heparin therapy for 2 days prior to the test.

Blue top (sodium citrate) tube

Plasma

1 mL

1. Blood should be collected in a blue top tube containing 3.2% buffered sodium citrate.
2. DO NOT DRAW FROM AN ARM WITH A HEPARIN LOCK OR HEPARINIZED CATHETER. A discard tube is not required prior to collection of coagulation samples. When non-citrate tubes are collected for other tests, collect sterile and nonadditive (red top) tubes prior to citrate (blue top) tubes. Any tubes containing an alternate anticoagulant should be collected after the blue top tubes. Gel barrier and serum tubes with clot initiators should also be collected after the citrate tubes.
3. Evacuated collection tubes must be filled to completion to ensure a proper blood to anticoagulant ratio.
4. Mix the sample immediately by gentle inversion at least 6 times to ensure adequate mixing of the anticoagulant with the blood.

1. Centrifuge and using a transfer pipette, carefully remove the plasma without disturbing the cells. Transfer the plasma into a plastic screw cap transport tube.
2. THE SPECIMEN SHOULD BE FROZEN IMMEDIATELY AND MAINTAINED FROZEN UNTIL TESTED.

Frozen

Samples that have gross hemolysis, are clotted or have thawed in transit will be rejected.

85635 - Reptilase Time (EAP 30021119)

The reptilase time measures the rate of fibrin clot formation after the addition of reptilase, a proteolytic enzyme derived from the venom of Bothrops atrox, to citrated plasma.

To avoid delays in turn around time when requesting multiple tests on frozen samples, submit separate frozen specimens for each test requested.