Laboratory Medicine
Test Directory / Activated Partial Thromboplastin Time
Activated Partial Thromboplastin Time
Citrated Plasma
| Test | Activated Partial Thromboplastin Time |
|---|---|
| Common Abbreviations | APTT |
| Profile | Coagulation Screen ( if required during authorisation: Actin FS APTT / APTT Mixing studies to exclude coagulation inhibitor presence) |
| Clinical Indication | Screening test for secondary haemostasis. Abnormal results may suggest factor deficiency |
| Specimen Type | Blood |
| Sample Type | Citrated Plasma |
| Minimum Volume | 1 x 3 mL (adult) 1 x 1 mL (paed) (citrated plasma must be filled to bottle line) |
| Special Precautions | Must state if patient is on anticoagulants (DOAC, Warfarin, Heparin); known coagulation disorders; clinical symptoms (bleeding, bruising). |
| Stability | 4-6 hours |
| Turnaround Time | 1 hour (urgent) 4 hours (routine) |
| Laboratory | York & Scarborough Hospital |
| Reference Interval | Reference range printed on final report. |
| Limitations | Haemolysis, gross lipaemia, high haematocrit may interfere with measurement. Over or under filled samples cannot be used due to ratio between blood and citrate |
| Additional Information |






