| Primary
Name |
Partial Thromboplastin Time |
| Synonym |
Partial
Thromboplastin Time |
| Synonym |
Activated
PTT |
| Contraction |
APTT |
| Contraction |
PTT |
| Contraction |
-- |
| UAB
Procedure Number |
2500140 |
| CPT
Code |
85730 |
| Specimen |
Collect
one (1) blue-stopper tube (3.2% sodium citrate), filled to specified
volume. Do not underfill or overfill.
|
| Specimen
Management |
Centrifuge
blue-stopper tube within 1 hour of collection, separate
plasma and test or quick-freeze at -70°C. |
| Specimen
Accepted |
Daily
including weekends |
| Times
Available |
All
times |
| Test
Performed |
All
times |
| Available
Stat? |
Yes |
| Description |
APTT
is performed to monitor unfractionated heparin therapy, detect coagulation
inhibitors, and to detect factor deficiencies of the intrinsic and common
pathways. Prolonged APTTs in the absence of heparin require APTT mixing
studies. |
| Reference
Interval |
25-34
seconds |
| Critical
Value |
>=120
seconds |
| Therapeutic
Range |
*Intravenous
heparin: 75-120 seconds *Subcutaneous heparin: 50-85 seconds |
| Follow-up
Test |
APTT
mixing studies |
| Associated
With |
Coagulation
factor inhibitors |
| Associated
With |
Bleeding
disorders |
| Associated
With |
Venous
thrombosis |
| Associated
With |
Heparin
therapy |
| Associated
With |
Lupus
anticoagulant |
| Associated
With |
Disseminated
intravascular coagulation |
