Exploratory studies of extended storage of apheresis platelets in a platelet additive solution (PAS)

Abstract

To evaluate the poststorage viability of apheresis platelets stored for up to 18 days in 80% platelet additive solution (PAS)/20% plasma, 117 healthy subjects donated platelets using the Haemonetics MCS+, COBE Spectra (Spectra), or Trima Accel (Trima) systems. Control platelets from the same subjects were compared with their stored test PAS platelets by radiolabeling their stored and control platelets with either (51)chromium or (111)indium. Trima platelets met Food and Drug Administration poststorage platelet viability criteria for only 7 days vs almost 13 days for Haemonetics platelets; ie, platelet recoveries after these storage times averaged 44 ± 3% vs 49 ± 3% and survivals were 5.4 ± 0.3 vs 4.6 ± 0.3 days, respectively. The differences in storage duration are likely related to both the collection system and the storage bag. The Spectra and Trima platelets were hyperconcentrated during collection, and PAS was added, whereas the Haemonetics platelets were elutriated with PAS, which may have resulted in less collection injury. When Spectra and Trima platelets were stored in Haemonetics' bags, poststorage viability was significantly improved. Platelet viability is better maintained in vitro than in vivo, allowing substantial increases in platelet storage times. However, implementation will require resolution of potential bacterial overgrowth during storage.

Figure 1

Recoveries and survivals of stored apheresis platelets. (A) Recoveries of Haemonetics, Spectra, and Trima platelets stored for 1 to 18 days. (B) Survivals of Haemonetics, Spectra, and Trima platelets stored for 1 to 18 days. ●, data for Haemonetics stored platelets in CLX bags; ▲, for Spectra stored platelets; ▪, for Trima stored platelets. All data are given for platelets stored in each system’s own bags. Data are given as average ±1 standard error.

Figure 2

Stored platelet recoveries and survivals as a percentage of control platelets (fresh or 1-day plasma-stored platelets). (A) Stored platelet recoveries compared with control platelets. (B) Stored platelet survivals compared with control platelets. Shown are the 2-sided LCLs for the mean difference between the stored platelets and the proportion of the fresh or 1-day plasma platelets (control platelets) specified by the FDA criteria. The LCLs are a function of both the means and standard deviations of these differences. These limits have been transformed to a percent of control scale. The horizontal, dashed lines show the critical values specified by FDA’s poststorage platelet viability criteria; ie, platelet recoveries should be ≥66% and survivals ≥58% of each subject’s paired control platelets. ●, data for Haemonetics MCS+ platelets in CLX bags; ○, in CPP bags; ▪, for Trima platelets in Terumo BCT bags; and □, in Haemonetics CLX bags.

Figure 3

Relationship between poststorage pH and storage volume, platelet concentration, total platelet count, and poststorage pCO₂, pO₂, and glucose for Haemonetics, Spectra, or Trima collected platelets. (A) Poststorage pH vs storage volume. (B) Poststorage pH vs platelet concentration. (C) Poststorage pH vs total platelet count. (D) Poststorage pH vs poststorage pCO₂. (E) Poststorage pH vs poststorage pO₂. (F) Poststorage pH vs poststorage glucose concentration. ●, data for Haemonetics platelets in CLX bag; ○, in CPP bags; ▪, for Trima platelets in Terumo BCT bags; □, in Haemonetics CLX bags; ▲, for Spectra platelets in Terumo BCT bags; and △, in Haemonetics CLX bags.

Figure 4

Relationship between post-transfusion in vivo vs in vitro data. (A) Poststorage platelet recoveries vs in vitro measurements. (B) Poststorage platelet survivals vs in vitro measurements. ●, data for Haemonetics platelets in CLX bag; ○, in CPP bags; ▪, for Trima platelets in Terumo BCT bags; □, in Haemonetics CLX bags; ▲, for Spectra platelets in Terumo BCT bags; and △, in Haemonetics CLX bags. The regression lines for the data are shown as the hatched lines, and the r² values are given on the figures.