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HelpTest Code APTT Partial Thromboplastin Time - APTT/PTT
Synonyms/Keywords
PTT, APTT, Activated Partial Thromboplastin Time
Specimen Requirements
| Fasting Required | Specimen Type | Preferred Container/Tube | Acceptable Container/Tube | Specimen Volume | Specimen Minimum Volume (allows for 1 repeat) |
Pediatric Minimum Volume (no repeat) |
|---|---|---|---|---|---|---|
| No | Whole Blood, Plasma | 3.2% Citrated Blue Top Tube (BTT) | 1.0 mL Plasma | 0.6 mL Plasma |
Collection/Processing Instructions
- Citrated Blue Top Tube (BTT) must be drawn to the fill line.
- Completely invert tube three or four times to mix. Do Not Shake.
- Centrifuge tube at 3000 rpm for 10 minutes or Stat Spin for 3 minutes at 8500 rpm with the brake OFF as soon as possible after collection.
- Perform testing within 4 hours of sample collection or transfer plasma (avoiding platelet contamination) to polypropylene tube with plastic pipette for storage within two hours of collection.polypropylene tube with plastic pipette for storage within two hours of collection.plastic pipette for storage within two hours of collection.
- If sending to another testing location: When APTT and Protime-INR are ordered together send only one frozen, plasma aliquot (1mL) for both tests, labeled with the APTT and Protime-INR specimen labels. Separate Citrated Blue Top Tube (BTT) or room temperature plasma is not needed.
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Whole Blood or Plasma | Ambient or Refrigerated | 4 Hours |
| Plasma | Frozen (-18C) | 2 Weeks |
| Frozen (-70C) | 6 Months | |
| Frozen thawed | 2 Hours |
Rejection Criteria
| Reject at gross hemolysis |
|---|
| Specimens filled below the fill line |
| Clotted |
| Frozen whole blood |
| Known IV fluid or Hickman line fluid contamination |
| Specimens with abnormal results that have a Hct >55% that have not had the citrate anticoagulant adjusted |
Test Information
Therapeutic heparin range 40.0 - 60.0 seconds
Moderate hemolysis does not interfere with sample analysis, however it may be an indicator of clotting factor activation prior to testing. Clinical correlation with results recommmended.
Reference Range Information
| Performing Location | Reference Range |
|---|---|
| All Performing Sites | 22.0 - 30.0 seconds |
| See Critical Value List for list of current critical values | |
Marshfield Labs Performing Department
Marshfield Labs Hematology
Performing Information
| Performing Location | Day(s) Test Performed | Analytical Time | Methodology/Instrumentation |
|---|---|---|---|
| Beaver Dam | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Weston | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Eau Claire | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Park Falls | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Ladysmith Medical Center | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Lakeview Medical Center | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Marshfield | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Minocqua | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
| Neillsville | Monday through Sunday | Less than 2 hours | Optical Clot Detection/Sysmex CS-2500 |
CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 85730 |
Outreach CPT Codes
| CPT | Modifier (if needed) |
Quantity | Description | Comments |
|---|---|---|---|---|
| 85730 |
Ordering Applications
| Ordering Application | Description |
|---|---|
| Cerner | PTT |