PARTIAL THROMBOPLASTIN TIME (PTT)
: aPTT, Activated Partial Thromboplastin Time, PTT
: 23-34 seconds
: Light blue top (Sodium Citrate)
: Citrated platelet poor plasma - Requires double centrifugation if sending a plasma aliquot. Aliquot(s) must be frozen if not received by lab within 4 hours of collection.
: Pediatric: One 2.7mL Light blue top - 3.2% Sodium Citrate. Neonatal: One 1.8mL Light blue top - 3.2% Sodium Citrate.
: 1.0 mL plasma
: 1.0 mL plasma
: Room Temperature for Light blue top tube, must be received within 4 hours of draw. Plasma aliquot(s) must be frozen if not received by lab within 4 hours of collection.
: Room temperature: 4 hours, if patient is on Heparin: 2 hours
Reasons for Rejection
: Clotted sample, incorrectly filled tubes, incorrect tube type, grossly hemolyzed sample, grossly lipemic sample, grossly icteric sample, whole blood >4.0 hours old.CLICK HERE FOR COAGULATION SPECIMEN COLLECTION GUIDE.
: 2 hours, once received into the lab
: Direct Thrombin and both Direct and Indirect anti-Xa inhibitors may interfere with these assays. Coumadin will interfere with these assays. Heparins will interfere with these assays.
: Indwelling line should be flushed with saline and 5.0 mL of blood discarded before collecting samples for coagulation assays. Tube must be full and not clotted. Deliver to lab immediately. Samples received from an outside lab must be aliquoted and frozen. Samples aliquoted for shipping must be double centrifuged prior to freezing. Grossly hemolyzed, icteric or lipemic samples may be rejected.
Search Options for the Test Directory:
1. Enter the test name in the Keyword search field.
Hint: You can also enter any part of the test name to expand the search.
(Example: you can type "west" or "sed" or "rate" to find Westergren Sedimentation Rate)
2. Enter the Vanderbilt Test Code, if known.
3. Choose one of the letter boxes to display a list of all test names and keywords starting with that letter.
If you are unable to find a test in our directory, please contact VPLS at
1-800-551-5227 or e-mail firstname.lastname@example.org.