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Activated Partial Thromboplastin Time (APTT, PTT)

Light Blue Top Tube

Tube Type

Test ID   LAB325
EPIC Order
CPT Code(s)   85730
Group/Individual Test   Individual
Laboratory   Core Laboratory
Tube Station   30 Routine, 888 STAT
Specimen Routine: 2.7 mL blood/light blue top tube; see Comments for additional information
Pediatric: 1.8 mL blood/pediatric light blue top tube
Unspun 4 hrs
Refrigerate NO
Frozen 14 days (plasma only)
Room Temperature 4 hrs
Availability Routine: 24 hrs/day
  STAT: Yes
Turnaround Time   Stat 1 hr, Routine 2 hrs
Reference Range <6 mos: Undefined
  >6 mos: 24.9-36.9 seconds
  Critical: >165 seconds
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 June 25, 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