PTT (ACTIVATED PARTIAL THROMBOPLASTIN TIME)

Message

A hematocrit value >55% may lead to spurious coagulation results.

Test Code

LAB325

Preferred Specimen

One 3 mL blue top tube
Pediatric: One 1.8 mL pediatric blue top tube

Minimum Volume

1 mL plasma

Instructions

Tube must be filled to the etched line. Immediately after drawing gently invert the specimen 3 to 4 times. Do not shake.

Samples must be centrifuged at 3000 rpm for 10 minutes or using a high-speed centrifuge. Platelet poor plasma should be separated into 1 ml aliquots. Samples should be frozen within one hour (best practice), however samples stable for 4 hours. Samples must remain frozen during transport. Any samples that are received thawed are not suitable for testing.

Transport Temperature

Frozen (1 mL plasma aliquot)

Specimen Stability

Ambient: 4 hours if cap has not been removed or punctured
Frozen: 6 months (-70C)

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Clotted specimen, underfilled tube, or gross hemolysis.

Methodology
Optical Density on ACL TOP using SynthASil aPTT reagent

Setup Schedule

Sunday-Saturday

Clinical Significance

Interpretive Information
Therapeutic range for unfractionated heparin is 60.0 to 100.0 seconds.

Direct oral anticoagulants can effect coagulation testing results.

Performing Laboratory
West Virginia University Hospital, Inc.
Berkeley Medical Center
Braxton County Memorial Hospital
Camden Clark Medical Center
Fairmont Medical Center
Jackson General Hospital
Jefferson Medical Center
Potomac Valley Hospital
Reynolds Memorial Hospital
Summersville Regional Medical Center
St Joseph's Hospital
United Hospital Center
Wetzel County Hospital

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.