PARTIAL THROMBOPLASTIN TIME (PTT), CIRCULATING ANTICOAGULANT, PLASMA

Additional Codes

Software	Test Code
Label Text	PTTCA
EPIC	LAB326

Performing Laboratory

NorDx Laboratories

Useful For

Aiding in the assessment of an unexplained prolonged partial prothrombin time

Method Name

Mixing Study performed with normal plasma

Reference Values

An interpretive report will be issued

Days and Times Test Performed

Mondays

Specimen must be received in the Maine Medical Center laboratory by 10:00 a.m.

A STAT version of the test is provided on other days as a “quick 50/50” mix.

Report Available

Up to 1 Week

Profile Information

Individual Test Description
PTT CIRCULATING ANTICOAGULANT
THROMBIN CLOTTING TIME, PLASMA

Specimen Type

Plasma

Preferred Container

Light Blue Top Tube (Sodium Citrate) – Tubes must be full at time of collection.

Plasma from a minimum of 2 tubes is required for this test.

Specimen Collection and Handling

Collect specimen as follows:

1. Draw blood in light blue-top (3.2% sodium citrate) tubes. Tubes must be full upon collection.

2. Separate plasma from cells as soon as possible within 4 hours of collection in a centrifuge at 2,500 rpm for 15 minutes or 3,000 rpm for 10 minutes.

3. Using a plastic transfer pipette (do not use a glass pipette) decant the plasma to a screw-capped, plastic (polypropylene) vial. Glass vials will not be accepted.

4. Spin the plasma again at 2,500 rpm for 15 minutes or 3,000 rpm for 10 minutes. Note: Double spinning the specimen ensures platelet poor plasma (<10,000 uL)

5. Divide the plasma into as many 0.5-1.0 mL aliquots as possible and cap the vials tightly.

6. Place tubes upright and flash freeze specimens immediately at ≤ – 20° C or below.

7. Send specimens FROZEN on dry ice.

Click here to view the Procedure for Collecting a Specimen from an A-line

Specimen Stability Information

Specimen Type: Plasma

Room Temp: 4 Hours

Note: Whole blood that remains capped and unspun is stable for up to 4 hours when stored at room temperature (18 – 24°C). Frozen plasma is stable 2 weeks @ -20°C and 12 months @ -70°C. Blue top tubes for coag assays must not be refrigerated or placed on ice.

Add On Capable

Yes

Advance Beneficiary Notice Requirements

No ABN Required

CPT Code Information

CPT Code	CPT Description	CPT Disclaimer
85732 x4	Thromboplastin Time, Substitution, Plasma Fractions, Each

Keywords

MIXING STUDY

PARTIAL THROMBOPLASTIN TIME (PTT)

Performing Laboratory Location