Sign in →

Test ID PTTP Prothrombin Time, Plasma

Secondary ID

40934

Useful For

Screening assay to detect deficiencies of one or more coagulation factors (factors I, II, V, VII, X)

 

Screening assay to detect coagulation inhibition

 

Monitoring intensity of oral anticoagulant therapy when combined with international normalized ratio (INR) reporting

Specimen Type

Plasma Na Cit


Specimen Required


Specimen Type: Platelet-poor plasma

Collection Container/Tube: Light-blue top (3.2% sodium citrate)

Submission Container/Tube: Plastic vial

Specimen Volume: 1 mL platelet-poor plasma

Collection Instructions:

1. For complete instructions see Coagulation Guidelines for Specimen Handling and Processing

2. Centrifuge, remove plasma, and centrifuge plasma again.

3. Aliquot plasma into plastic vial leaving 0.25 mL in the bottom of centrifuged vial.

Additional Information: A double-centrifuged specimen is critical for accurate results as platelet contamination may cause spurious results.


Specimen Stability Information

Specimen Type Temperature Time
Plasma Na Cit Frozen (preferred) 30 days
  Ambient  24 hours

Reject Due To

Gross hemolysis Reject
Gross lipemia OK
Gross icterus OK

Reference Values

PROTHROMBIN TIME:

9.4-12.5 seconds

 

INTERNATIONAL NORMALIZED RATIO (INR):

0.9-1.1

 

Standard intensity warfarin therapeutic range: 2.0-3.0

High intensity warfarin therapeutic range: 2.5-3.5

Day(s) Performed

Monday through Sunday

Report Available

Same day/1 day

Performing Laboratory

Mayo Clinic Laboratories in Rochester

CPT Code Information

85610

Forms

If not ordering electronically, complete, print, and send a Kidney Transplant Test Request with the specimen.