| Test Name: | T3, Free (Triiodothyronine) |
| Epic Order Code: | LAB137 |
| CPT Code: | 84481 | | |
| Specimen(s) Type: | Plasma or Serum, 0.5 mL |
| Acceptable Container(s): |   Tube tops are light green and gold. |
| Testing Schedule: | 24 hrs/day, 7 days/week |
| Turn Around Time: | STAT: 1 hour | | |
| | Routine: 2 hours |
| Collection Information: | No special patient preparation is required. Obtain specimen by standard collection procedures. |
| Transport Information: | Deliver to lab immediately. All specimens must be signed into the laboratory. |
| Reference Clients: | If unable to deliver to the lab within 1 hour, centrifuge the specimen and remove plasma/serum from the red cells. Store and transport at 2-8° C. Specimen must be received in the lab within 24 hours. |
| Causes for Rejection: | Improperly labeled, incorrect container, contaminated, insufficient quantity, incorrect/delay in transport. |
| Reference Range: | 0 - 4 days: 197 - 787 pg/dL |
| | 4 days - 2 mos: 196 - 524 pg/dL |
| | 2 mos - 2 yrs: 155 - 638 pg/dL |
| | 2 - 7 yrs: 196 - 595 pg/dL |
| | 7 - 12 yrs: 268 - 516 pg/dL |
| | 12 - 19 yrs: 228 - 501 pg/dL |
| | > 19 yrs: 200 - 440 pg/dL |
| Additional Information: | Any influence that might affect the binding behavior of the binding proteins can alter the result of the Free T3 tests, i.e., drugs, NTIs (Non-Thyroid Illness) or patients suffering from FDH (Familial Dysalbuminemic Hyperthyroxinemia). |
| | Autoantibodies to thyroid hormones can interfere with the assay. |