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Prothrombin Time (PT)

Light Blue Top Tube

Tube Type

Test ID   LAB320
EPIC Order
CPT Code(s)   85610
Group/Individual Test   Group
Laboratory   Core Laboratory
Tube Station   30 Routine: 888 STAT
Specimen Routine: 2.7 mL blood/light blue top tube; see Comments
  Pediatric: 1.8 mL blood/pediatric light blue top tube
Unspun: 24 hours
Room temperature: 24 hours
Refrigerator: NO
Frozen: 14 days (platelet poor plasma only)
Availability Routine: 24 hr/day
Turnaround Time   Stat: 1 hour; Routine: 2 hours
Reference Range Age <6mos: Not defined
  Age >6 mos: 10.3-13.4 secs  (Corresponding INR: 0.9-1.1)
  Critical Value: >55 secs
Comments Deliver Immediately
Reference Range changes with reagent lot number. Draw tube must be allowed to fill completely. Short draws will be rejected.

Reviewed by Christopher Parker on September 15, 2021

Note: Reference ranges provided on this web site are for guidance only, and may not reflect the most recent changes. Refer to laboratory reports for current reference data.

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514