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Antithrombin III Activity (AT III ACT)

Tube Type = Light Blue Top Tube

Tube Type

Test ID LAB311
EPIC Order ANTITHROMBIN III
CPT Code(s) 85300
Group/Individual Test Individual
Laboratory Core Laboratory
Tube Station 30 Routine: 888 STAT
Specimen Routine: 2.7 mL blood/Lt Blue Sodium Citrate tube; See Comments 
Pediatric: 1.8 mL blood pediatric light blue top tube; See Comments
Stability Unspun: 4 hours
Room Temperature: 4 hours
Refrigerated: NO
Frozen: 14 days (plasma only)
Availability Routine: 24 hours/day
STAT: YES
Turnaround Time Stat 1 hr; Routine 2 hrs
Reference Range Normal: 80-130% of normal
Critical: <46% of normal
Comments
  • Deliver Immediately. Draw tube must be allowed to fill completely. Short draws will be rejected.

Reviewed by J. Carr on November 19, 2025

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