Prothrombin Time w/ Reflex to Heparin Neutralization
| Alternate Names | PT, INR, PTINR, PT/INR |
| Ordering Recommendation | Useful to screen for abnormalities of coagulation factors that are involved in the extrinsic pathway. Also used to monitor effects of Warfarin therapy and to study patients with hereditary and acquired clotting disorders. |
| Specimen | Sodium Citrate Plasma |
| Container Type | Light Blue Top Tube
|
| Tests Included | International Normalized Ratio (INR)
All Prothrombin Time orders with INR ≥ 5.0 will be reflexed to Heparin Neutralization and reported with the comment attached: “This PT/INR result is from a specimen treated with Heparin Adsorbent and allows the physician to determine approximate values.” |
| Methodology | Optical Clot Detection |
| Calculation | |
| Reference Range | Prothrombin Time: 9.7 – 11.4 seconds
INR: 0.94-1.09 |
| Stability | 2 days |
| Transport Temp | Room Temperature (Preferred) or Refrigerate 2°-8° C (Acceptable) |
| Instructions | To ensure accurate results, collection via indwelling lines and other vascular access devices containing solutions that will impact results (e.g., heparin, alteplase) should be avoided. If not possible, it is recommended that a minimum of 6 times the dead-space volume of the device and all connected tubing be discarded prior to collection for coagulation testing.
The heparin neutralization procedure neutralizes up to 2 units of heparin per 1 mL of plasma. A specimen with more than this amount of heparin cannot be corrected by the neutralization procedure. Failure to clear heparin and similar solutions from access lines will compromise test results. |
| Days Performed | Daily |
| Report Available | 1 Day |
| NY State Available | Yes |
| LOINC Code | 5902-2 (PT), 6301-6 (INR), 3269-8 (Heparin Neutralization) |
| CPT Code | 85610 (PT/INR) 85525 (Heparin Neutralization) |
