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22759 Partial Thromboplastin Time - APTT/PTT

Partial Thromboplastin Time - APTT/PTT
Test Code: APTT
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 (-18°C)​ 2 Weeks​
Frozen (-70°C)​ 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​
Performing Laboratory 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​
Test Information

​Therapeutic heparin range 45-70 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 23.5 - 32.1 seconds​
​ See Critical Value List for list of current critical values​
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
85730​
Synonyms/Keywords
​PTT, APTT, Activated Partial Thromboplastin Time​
Ordering Applications
Ordering Application Description
​Cerner ​PTT
If the ordering application you are looking for is not listed, contact your local laboratory for assistance.
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
-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 (-18°C)​ 2 Weeks​
Frozen (-70°C)​ 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​
Reference Range Information
Performing Location Reference Range
All Performing Sites 23.5 - 32.1 seconds​
​ See Critical Value List for list of current critical values​
For more information visit:
Performing Laboratory 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​
For billing questions, see Contacts
Outreach CPTs
CPT Modifier
(if needed)
Quantity Description Comments
85730​
For most current information refer to the Marshfield Laboratory online reference manual.