Prothrombin Time (PT) and Partial Thromboplastin Time (PTT)

Collection Instruction

2.7 mL blood in a light blue-top (3.2% sodium citrate) plastic tube Immediately centrifuge at 3,500 rpm for 10 minutes to completely remove platelets if sending plasma. Or 3.5 mL blood in Greiner Bio-One Vacuette Light blue-top (3.2% sodium citrate) PLASTIC tube (REFERRAL CLIENTS ONLY). Immediately centrifuge at 3,500 rpm for 10 minutes to completely remove platelets if sending plasma. A clean venipuncture is essential to avoid specimen activation. The correct ratio of blood to anticoagulant (9:1) is critical. If the tubes are under-filled, specimen must be recollected as results will not be accurate. DO NOT COLLECT SPECIMEN IN GLASS TUBES. Refrigerated unacceptable.

Specimen Stability

2 Weeks (Frozen -70°C)

CPT Code(s)

85610, 85730

Turnaround Time

72 Hours

Reference Range