Background: The quality of platelet (PLT) concentrates (PCs) can be evaluated with various in vitro methods. A new technique, free oscillation rheometry (FOR), can be used to monitor coagulation properties of PCs and gives information on clotting time and coagulum elasticity. This study compared the quality of apheresis PCs produced by the COBE Spectra and Trima Accel cell separators (both Gambro BCT) during storage for 7 days with in vitro tests including FOR.
Study design and methods: Apheresis PCs were collected with the COBE Spectra (n = 10) and Trima Accel (n = 10) cell separators. Swirling, blood gases, and metabolic variables were analyzed on Day 0. Samples taken on Days 1, 5, and 7 were also analyzed for hypotonic shock response (HSR), P-selectin, and glycoprotein (GP)Ib expression and evaluation of coagulation by FOR.
Results: Swirling, HSR, and percent GPIb-expressing PLTs were well maintained for 7 days, whereas glucose decreased and lactate increased significantly during storage for both Spectra and Trima PCs. Percent P-selectin-expressing cells increased to the same extent in both types of PCs during storage. pH increased between Day 0 and Day 1 but then decreased. The clotting time remained constant throughout the storage period whereas the development of elasticity was reduced on Days 5 and 7 compared to Day 1 (p < 0.05) for both types of PCs.
Conclusion: The results indicate that the PLT quality after storage for 7 days is well preserved, although activation of PLTs occurs during storage as assessed by in vitro tests. No difference in PLT quality was observed between Spectra- and Trima-produced PCs.