aPTT(Post-Heparin Removal)
| Also Known as (Alias) | PTT |
| Indications | Prolonged aPTT in a patient suspected of receiving heparin or having had blood drawn through a heparinized catheter or port. |
| Method | Clottable |
| Test Information | Therapeutic anticoagulation interferes with most kinetic (but not DNA) tests. For specimens suspected of containing heparin, heparin is adsorbed using Hepzyme (Dade) reagent and the aPTT repeated. |
| Additional Test Information | If sample undergoes heparin removal, this test is ordered by lab. Normal ranges are included on testing report and can be made available upon request |
| Sample Requirements | Whole Blood: 3.2% sodium citrated (blue top) OR frozen plasma |
| Requested Volume | Two 5 ml 3.2% sodium citrated (blue top) tubes as whole blood OR frozen plasma in 4 X 1mL aliquots in plastic tubes |
| Minimum Volume or Pediatric Volume | Frozen Plasma: at least 0.5ml in 2 plastic tubes. |
| Sample Information | Whole blood is preferred for testing, but if it is not possible to send whole blood tubes TO ARRIVE HERE WITHIN 2 HOURS of collection, then send frozen plasma. To prepare plasma, centrifuge blue top tubes at 1500g for 15 minutes and remove the plasma and centrifuge a second time at 1500g for an additional 15 minutes. Aliquot approximately 1 ml of plasma into 4 plastic tubes, and freeze. |
| Shipping Information | Whole Blood: Send at ambient temperature (18-25°C) and must be received within the lab in less than or equal to 2 hours after collection.
Frozen Plasma: Send on dry ice. Send samples to: Bloodworks Northwest For additional information, please see Ordering Information |
| Requisition Form | RFT- Hemostasis Reference Laboratory |
| Transaction Code | 3200-05 |
| CPT Codes | 85730 |
| Test Schedule | Monday – Friday |
| Turn around Time (analytic time) | 3 Business Days |
| Report/Results | Fax number required to receive report |
