Storing apheresis platelets without agitation with simulated shipping conditions during two separate periods: immediately after collection and subsequently between Day 2 and Day 3.

BACKGROUND

Apheresis platelet (PLT) units are not routinely agitated during transit. Our study compared the in vitro properties of apheresis PLT units that were stored with continuous agitation (CA) and without continuous agitation (WCA) during two separate periods, immediately after collection and between Day 2 and Day 3 of storage.

STUDY DESIGN AND METHODS

Two identical apheresis PLTs units were prepared from collections with Amicus (n = 11, Fenwal, Inc.) and Trima (n = 10, CaridianBCT) cell separators. One apheresis PLT unit was continuously agitated, starting routinely within 30 minutes of collection, and an identical apheresis PLT unit was held without agitation initially for 7 to 8 hours and subsequently for 24 hours between Day 2 and Day 3 of storage. The apheresis PLT units were maintained WCA at 20 to 24 °C in a shipping box. In vitro PLT properties were evaluated on Day 1 (day after collection), after 5 and 7 days of storage.

RESULTS

With both Amicus and Trima apheresis PLT units, the mean PLT content and concentration of CA and WCA were comparable and essentially constant throughout storage. Mean pH levels (± 1 SD) after 5 days for Amicus apheresis PLT units were 6.97 ± 0.20 (WCA) and 7.13 ± 0.16 (p < 0.001, CA) and for Trima apheresis PLT units 6.97 ± 0.21 (WCA) and 7.22 ± 0.17 (p < 0.001, CA). In vitro variables, including percentage of disc PLTs, extent of shape change, and hypotonic stress levels, after 5 days of storage, showed mean differences between WCA and CA that were less than 15%.

CONCLUSION

The in vitro results show that apheresis PLT units can be stored without agitation for 7 to 8 hours immediately after collection and also subsequently during storage for 24 hours with minimal influence on in vitro PLT properties compared to continuously agitated PLTs.