J Lab Med Qual Assur 2010; 32(2): 205-210
Published online March 31, 2010
Copyright © Korean Association of External Quality Assessment Service.
Background: Plasma specimens are recently used instead of serum in clinical chemistry to improve (test result turnaround time, TAT). We evaluated the performance of lithium heparin gel plasma separating tube in comparison to existing vacutainer gel serum tube in common clinical chemistry assays.
Methods: Total 52 subjects who had visited the health promotion center were included in the study. Lithium heparin plasma tubes and serum tubes were tested for 30 clinical chemistry items and 3 cardiac markers. Test results were analyzed by calculation of mean bias and percent difference.
Results:The performance of the lithium heparin plasma tube was considered to be clinically equivalent to the serum tube for all assays except for potassium. The difference of potassium levels between lithium heparin plasma tube and the serum tube was -7.32%. Test results of some analytes including glucose, lactate dehydrogenase, total CO2 and potassium using the lithium heparin tube were significantly changed after 24 hours of storage.
Conclusions:The lithium heparin plasma tube provided acceptable results comparison to the existing serum separating tube in common clinical chemistries and can be used for reducing, TAT. However, the stability of plasma gel tubes on 24 hours of storage was unstable in some analytes, it requires attention.
Keywords: Plasma specimen, Vacutainer gel plasma tube, Serum gel separating tube