Laboratory Services

Thrombin Time

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Updated Test Information:

Test Description
Thrombin Time
Synonym(s)

UOW571

Test ID
TT
General Information

Thrombin Time measures the time it takes to convert fibrinogen to fibrin clot in the presence of known amount of (human) thrombin.

Container Type

3 mL or 5 mL Light Blue Citrate Tube

Specimen Type

Blood

Specimen Requirements

Entire Specimen

Specimen Collection / Processing Instructions

MUST PROCESS WITHIN 4 HOURS OF COLLECTION
Platelet poor Coag Citrate Specimen processing:
1. Gently invert tube 2-3 times prior to placing in Centrifuge
2. Centrifuge Citrate whole blood at 4500 rpm for 10 minutes
3. Carefully pipette plasma, avoiding the platelet/buffy coat into a plastic vial
4. Centrifuge plasma at 4500 rpm for 10 minutes
5. Pipette the plasma to a plastic vial, leaving the bottom 0.25 mL undisturbed
6. Freeze plasma immediately and transport frozen

Minimum Sample Volume

1 mL

Stability

Decant & Freeze plasma (minimum 1.0 mL) @ -20°C to -80°C. Send Frozen on dry ice.

Limitations

Thrombin Time is prolonged if an anticoagulant (e.g. heparin, LMW heparin, direct thrombin inhibitors) that inhibits thrombin is present or if fibrinogen levels are low.


Patients on hirudin (Refludan), argatroban (Novastatan), Dabigatran (Pradaxa) or bivalirudin (Angiomax) may show prolongation of thrombin time due to direct thrombin inhibition.

Department (code)

Coagulation (COAG)

Methodology

Clot based, Stago STA clotting assay

Testing Schedule

Daily

CPT Code(s)

85670

STAT Orderable (Y/N)

Yes

Performing Lab

UW

LOINC Code(s)