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HelpTest Code LAB324 Thrombin Time (TT)
Additional Codes
TT
Collection:
Specimen: Blood
Container: Blue Top Tube with 3.2% (0.109 M) buffered Sodium Citrate anticoagulant only
Specimen Volume: 3.5 mL Must be filled to arrow (Greiner tube Black Disk) or line (BD)
Pediatric Collection: 2.0 mL Must be filled to arrow (Greiner tube White Disk) or line (BD)
Notes:
- Samples not filled properly will be rejected (over or under filled).
- If the patient's hematocrit is >55%, call Lab Client Services at 792-0707 to obtain an anticoagulant adjusted tube.
- For collection information and guidance refer to MUSC Laboratory Services Hemostasis / Coagulation Collection Guideline.
Stability:
Room Temperature: 4 hours Whole Blood
Refrigerated: 4 hours Whole Blood
Frozen at or below -20°C: 2 weeks
Note: Frozen samples must be platelet poor plasma aliquoted from primary tube. Label as Na Citrate or blue top plasma.
Turnaround Time (TAT):
STAT: 1 HOUR
Routine: 3 HOURS
Test Availability:
Daily / 24 Hours / Available STAT
Reference Interval:
>/= 30 days – Adult: 16.2 – 19.6 seconds
<30 days: 20.0 - 26.2 seconds
Interpretive Data:
A prolonged Thrombin Time can be seen under the following conditions: 1. Hypofibrinogenemia or Dysfibrinogenemia 2. In the presence of Heparin contamination of the sample. 3. Due to a non-specific inhibitor eg. Paraproteinemia 4. In the presence of anticoagulants known as Direct Thrombin Inhibitors. 5. Markedly increased levels of Fibrinogen / Fibrin Degradation Products. Reference ranges for infants less than or equal to 30 days are for full term healthy infants only. Call laboratory (792-0707) to obtain reference values for premature healthy infants.
Performed Laboratory Section:
COAGULATION / UMC MAIN LABORATORY