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Optimization of the storage conditions for coagulation screening tests
Sultan Ayesh Mohammed Saghir1, Faisal Muti Al-Hassan, Omar Saeed Alsalahi
1Department of Transfusion Science, Advanced Medical and Dental Institute, University Sains, Malaysia. sultan_a1976@yahoo.com
Summary
Prothrombin time (PT) samples are reliable for up to 4 hours at room temperature, but not at refrigerator temperatures. Activated partial thromboplastin time (APTT) samples are stable for only 2 hours at room temperature or refrigerated.
Area of Science:
- Clinical Pathology
- Hematology
- Laboratory Medicine
Background:
- Accurate coagulation test results depend on proper sample handling.
- Establishing optimal storage conditions for prothrombin time (PT) and activated partial thromboplastin time (APTT) is crucial for reliable diagnostics.
Purpose of the Study:
- To determine the optimal storage temperature and time for PT and APTT.
- To assess the stability of PT and APTT at various intervals at room temperature and refrigerated conditions.
Main Methods:
- An experimental study was conducted involving 33 participants.
- Blood samples were analyzed for PT at 0, 4, 8, and 24 hours.
- APTT was measured at 0, 2, 6, and 8 hours at both room temperature and 4°C.
Main Results:
- PT samples showed no significant difference at room temperature up to 4 hours.
- Significant differences in PT were observed after 8 hours at room temperature and after 4 hours when refrigerated.
- APTT samples remained stable for 2 hours at both room temperature and refrigerated conditions, with significant changes thereafter.
Conclusions:
- PT samples are acceptable for testing up to 4 hours when stored at room temperature.
- Refrigerated PT samples are not recommended for testing beyond 4 hours.
- APTT samples should be tested within 2 hours of collection, regardless of storage temperature.
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