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HelpTest Code LAB2312 Partial Thromboplastin Time (PTT), 50:50 Mix, Plasma
Methodology
Absorbance measurement, Clot signature formation
Literature References:
HemosIL SynthASil (pn 20006800) package insert issued 02/2016, Instrumentation Laboratory.
Performing Laboratory
Barnes-Jewish Hospital Laboratory
Specimen Requirements
Specimen Type: Plasma
Container/Tube: Light-blue top (citrate)
Specimen Volume: 2 Full tubes
Specimen Minimum Volume: 2 full tubes
Collection Instructions:
- Draw a discard blue top tube prior to drawing a light-blue top (citrated) tube if using a Winged Infusion Set. Discard tube should be under filled and discarded.
- Clotted blood or an insufficient specimen is not acceptable.
- Avoid phlebotomy techniques which cause hemolysis and heparin contamination.
- Follow nursing policy on volume of blood to discard prior to collecting blood from indwelling heparinized catheters.
Analyte Stability:
4 hours at 18° C to 24° C
Additional Information: If the patient is a hospital patient and the hematocrit is >55%, call Barnes-Jewish Hematology Laboratory at 314-362-5203 for instructions.
Christian: Send specimen to BJH poured off at ambient temperature with Microbiology run. Stability is 4 hours ambient.
Specimen Transport Temperature
Ambient/Refrigerate NO/Frozen NO
Reference Values
28 - 38 seconds (50:50 mix of patient and normal plasma will not correct a prolonged PTT if an inhibitor is present)
Physician alert value (automatic call-back): >150 seconds
Day(s) Test Set Up
Monday through Sunday
Turnaround Time:
STAT: 2 hour after receipt in laboratory
Routine: 2-4 hours after receipt in laboratory
Test Classification and CPT Coding
85730 -PTT activated straight
85732 x 2-PTT activated 50:50
Additional Information
For BJH Laboratory Use Only
Analyte Stability:
4 hours at 18o C to 24° C
Laboratory Processing Instructions:
Test performed in BJH Core Lab.
LOINC Code Information
Name LOINC Code
PTT activated straight 14979-9
PTT incubation mix 5946-9
PTT immediate mix 30323-0