Mix PTT Panel
Label Mnemonic: MIX
Epic code: LAB1110
Order form: Laboratory Requisition
Supply order: Supply Order Form
Billing: Billing Policies
CPT code: 85730, 85732, 85384, 85670
Specimen(s):
Collection Medium:
Light Blue top tube 2.7 mL (Na Citrate)
Minimum:
Full draw; 2.7 mL light blue top (mix well).
Rejection Criteria:
QNS, clot, excessive hemolysis
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
2 hours (upon receipt in laboratory)
Reference Range:
PTT = 22-31 sec
MPTT = 22-31 sec
Fibg = 194-448 mg/dL
TT = 17-20 sec

Fibg and TT reference ranges updated on 12/16/2019 due to new assay reagents.
Interpretive Data:
A PTT mix panel is performed to screen for a factor deficiency or inhibitor.
Comments:
A MIX testing panel should have its own draw tube and not be combined with other coagulation tests or panels to ensure an adequate amount of plasma for testing.
Methodology:
Optical clot detection.
Sample Processing:
Double-centrifuge specimen to prepare platelet-free plasma.
Immediately centrifuge specimen at 3500 RPM for 12 minutes.
Using a plastic transfer pipette, carefully remove plasma from cells avoiding the platelet/buffy coat.
Place plasma into a labeled plastic tube.
Centrifuge plasma again at 3500 RPM for 12 minutes.
Remove the top of the plasma and place into a labeled plastic tube.
Freeze double-spun plasma within 4 hours of collection time at -20 degrees C or below.
Sample Storage:
Freeze specimen immediately.
Transport Instructions:
Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place requisition into outside pocket of bag.
Place dry ice on top of specimen in Styrofoam container to maintain frozen temperature.
Samples received thawed will be cancelled.