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Test Code
T3FED
Test Name
Triiodothyronine (T3), Free, Dialysis and LC/MS-MS
CPT Codes
84481
Expected Turnaround Time
7 to 10 days
Specimen and Container Info

Preferred Specimen Type: Serum

Preferred Collection Container: Red Top, Plain

Alternate Collection Container: Gold Top, Serum Separator

Desired Specimen Volume: 1 mL
Collection Instructions
  1. Collect specimen in red top, plain tube or gold top, serum separator tube via venipuncture.
Processing and Submission Instructions
  1. Separate serum from cells within 45 minutes of collection.
  2. Transfer 1 mL of serum to a LabCorp PP transpak frozen purple tube.
Transport Instructions

Transport to the laboratory frozen. 
Stability Requirements

Room Temperature

5 days

Refrigerated

5 days

Frozen

70 days
Causes for Rejection

Whole blood
Methodology
Equilibrium Dialysis/Quantitative High Performance Liquid Chromatography-Tandem Mass Spectrometry
Reference Intervals

See patient report.
Alternate Names

Free T3

Free Triiodothyronine (T3)

FT3
Reference Lab
Labcorp Of America Holdings
Testing Schedule
Monday-Friday
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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