• apheresis platelets;
  • platelet storage;
  • platelets

Background and Objectives

The purpose of our studies was to determine the effects of extended platelet storage on poststorage platelet viability.

Materials and Methods

Normal subjects were recruited to donate platelets using two different apheresis systems: either the COBE Spectra (n = 58) or the Haemonetics MCS+ (n = 84). Platelet recovery and survival data from the two systems were compared with each other and with in vitro measurements of the stored platelets.


There were no significant differences in either platelet recoveries or survivals between the two machines between 1 and 8 days of storage. Combining the data from both machines, platelet recoveries decreased by 2·6% and survivals by 0·3 days/storage day. In vitro assays did not predict either platelet recoveries or survivals during storage for 5–8 days. After 9 days of storage, pHs were unacceptable (≤ 6·1), suggesting that 8 days will be the longest possible storage time.


These data suggest that, if stored platelet bacterial contamination issues are resolved, significant extension of platelet storage times is possible.