PTT (Partial Thromboplastin Time)

SIM

20480 

CPT

83570 

Synonyms

PTT;  Activated Partial Thromboplastin Time (APTT) 

Specimen Type

Sodium Citrate Plasma 

Container

4.5 ml Sodium Citrate 3.2% Blue stopper tube

Collection Instructions

None

Volume

4 ml plasma 
Min: 2.0 ml 

Additional Information

Hemolysis does not affect this assay.

Patient Preparation

none

Specimen Processing Instructions

Option 1 -Platelet Poor Plasma: Frozen Samples Centrifuge at 3380 rpm’s (±100) for 5 minutes. Remove the plasma without disturbing the cellular layer. Centrifuge again at 3380 rpm's (±100) for 5 minutes. Remove the platelet poor plasma to a transfer tube. 

Option 2 -Room Temperature send original collection tube ( only stable for 4 hours)

Transport Requirements

Room Temperature (Whole Blood or Room Temperature platelet poor plasma)

Frozen (Platelet poor plasma)

Specimen Stability

Room Temperature Whole Blood 4 hours

Room Temperature Plasma 4 hours

Frozen Platelet Poor Plasma at -20°C.  (Stable frozen for 14 days.) 

Rejection Criteria

•  Clotted Sample 
•  Insufficient volume

Reference Range

23.3 – 36.3 Seconds

Critical Value

>100 seconds 

Test Includes

PTT 

Methodology

Electromagnetic mechanical clot detection system 

Testing Frequency

Daily, Monday - Sunday 

Reviewed By

Summer Brochu

Reviewed Date

Supplemental