Test Code APTT Activated Partial Thromboplastin Time (aPTT)
Additional Codes
Epic: LAB2207
Specimen Required
Specimen Type: Platelet-poor plasma
Collection Container/Type: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Plastic vial
Specimen Volume: 1 mL
Collection Instructions:
- Centrifuge, remove plasma and centrifuge again.
- Aliquot plasma into plastic vial leaving 0.25 mL in the bottom of centrifuged vial.
For complete instructions, see Platelet Poor Plasma Instructions.
Specimen Type: Whole Blood, Sodium Citrate
Collection Container/Type: Light-blue top (3.2% sodium citrate)
Submission Container/Tube: Light-blue top (3.2% sodium citrate)
Specimen Volume: 2.7 mL
Collection Instructions:
- Collect sample, ensuring tube is completely filled to obtain a 9:1 (blood to anticoagulant) ratio.
- Submit sealed, unopened sample to laboratory.
Specimen Stability
Platelet-poor plasma
Room temperature
Outpatient: 12 hours
Inpatient: 4 hours
Refrigerated: Unacceptable
Frozen (-20ºC): 2 weeks
Frozen (-70ºC): 6 months
Whole Blood
Room temperature
Outpatient: 12 hours
Inpatient (not on heparin): 4 hours
Inpatient (on heparin): 1 hour
Refrigerated: Unacceptable
Frozen: Unacceptable
Reference Range
23 - 37 seconds
Rejection Due To
Samples that are short (QNS), over draws, clotted,
hemolyzed, or beyond stablility requirements may yield
incorrect results.
Report Available
Same day
Method Name
Coagulometric (Turbidimetric)
CPT Codes
85730
Day(s) Performed
Daily