Test Code PT Prothrombin Time w/ INR
Specimen Information
Obtain specimen using standard phlebotomy techniques.
No special patient preparation is necessary.
Container | Specimen | Temperature | Collect Vol | Submit Vol | Min Vol | Stability |
Blue Top Tube | Whole Blood | Ambient | To fill line | To fill line | To fill line | 24 hours |
Blue Top Tube | Plasma | Frozen | To fill line | 2.0 mL Plasma | 0.5 mL Plasma | 6 months |
Reject Due To:
- Above criteria not met
- Marked hemolysis
- Specimen unlabeled or mislabeled
- Tube under or overfilled.
Tubes must be filled to the fill line.
Instrumentation / Method
ACL TOP 350 CTS / Photo Optical Clot Detection
Test Schedule / Analytical Time / Test Priority
Daily / Same Day / Available STAT
Reference Range
10.2 - 12.9 Seconds
INR value valid only on patients on stabilized warfarin therapy. The recommended therapeutic range for warfarin (Coumadin) for most clinical indications is an INR of 2.0-3.0. An INR of 2.5-3.5 is recommended for patients with mechanical heart valves.
Critical Value(s):
INR: >4.0
CPT / LOINC / Order Code
Meditech | Medent | LOINC | CPT |
PT | PT | 5902-2 | 85610 |
INR | 6301-6 |