NHA Certified Phlebotomy Technician (CPT)Specimen HandlingHard
A phlebotomy technician needs to separate plasma from cells for a routine coagulation test (e.g., PT/INR). After collection, how soon should the specimen be centrifuged?
- AWithin 48 hours of collection.
- BWithin 8 hours of collection.
- CWithin 2 hours of collection.
- DWithin 24 hours of collection.
Show answer & explanationAnswer & explanation
Correct answer: C. Within 2 hours of collection.
For routine coagulation tests like PT/INR, plasma must be separated from cells by centrifugation within 2 hours of collection to prevent degradation of coagulation factors and ensure accurate results.
Why the other options are wrong
- A. 48 hours is completely unacceptable for routine coagulation specimen centrifugation, making results unreliable.
- B. 8 hours is too long for centrifugation of routine coagulation specimens, potentially leading to inaccurate results.
- D. 24 hours is far too long for routine coagulation specimen centrifugation, leading to significant degradation of factors.
Coagulation Specimen Centrifugation Time
Plasma for routine coagulation tests (e.g., PT, PTT, INR) must be separated from cellular components within a specific timeframe to preserve the integrity of labile coagulation factors.
- Centrifuge within 2 hours of collection.
- Prevents degradation of factors.
- Crucial for accurate PT/INR results.
Memory trick: Two hours is the limit, or the factors will diminish!