| Ordering Code | 5649 |
|---|---|
| Test Name | Heparin, Unfractionated (UFH) |
| Alias | Unfractionated Heparin Anti-Xa |
| Preferred Specimen | Plasma |
| Preferred Container | Citrate, 3.2% (Lt Blue) |
| Other Specimen/Container | Whole Blood in Citrate, 3.2% (Lt Blue) if testing is done within 1 hour. |
| Optimum Volume | Plasma = 1 mL Whole Blood = Entire tube |
| Collection Instructions | Draw full tube Mix tube well |
| Handling Instructions | Double centrifuge to produce platelet-poor plasma, avoid the WBC/platelet buffy layer, separate and freeze at -20 deg C immediately. Do NOT thaw once specimen is frozen. |
| Transport Requirements | Preferred method of transport is frozen plasma. |
| Specimen Stability | Ambient: 1 hour Whole Blood Ambient: 2 hours Plasma (Aliquoted) Frozen: 2 weeks Plasma |
| Rejection Criteria | Clotted, Contaminated, Hemolyzed, Improperly filled or underfilled tube, Collected in the wrong anticoagulant, Mislabeled, Specimen older than stability limits |
| Avail. Stat | YES |
| Analytic Time | 1 Day |
| Methodology | Chromogenic |
Reference range(s)
The reference ranges listed below are valid on this date of November 3, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| Heparin, Unfractionated (UFH) | ALL | TR=0.30-0.70 | TR=0.30-0.70 | IU/mL |
