Improved platelet recovery in cryopreserved platelets reconstituted in freeze-dried plasma

Cryopreserved platelets can support availability in settings where fresh platelets are inaccessible. Freeze-dried plasma (FDP) may serve as an alternative reconstitution medium to fresh frozen plasma (FFP) when plasma thawing is impractical. The effects of FDP on cryopreserved platelet quality remain underexplored. Thus, we aimed to evaluate its suitability.

Cryopreserved platelets were prepared from double-dose buffy-coat concentrates, split, prewashed, and frozen using dimethyl sulfoxide (DMSO) (5-6%). After thawing, paired units were resuspended in FFP (AB = 8) or FDP (OctaplasLG Powder, AB = 8). Platelet count and mean platelet volume were analyzed alongside blood gas parameters. Additionally, extracellular lactate dehydrogenase (LDH), sP-selectin, and VEGF were measured in the supernatant. Platelet markers (aggregation, adhesion, and activation) and microparticles were analyzed by flow cytometry. Clotting ability was evaluated using ROTEM.

After thawing, FDP units contained significantly more platelets than FFP units 206 ± 27 versus 176 ± 18 ×10⁹/units (p = .0006). LDH activity was lower (p = .040), whereas VEGF levels were higher (p = .0003) in the FDP group. Oxygen and carbon dioxide pressure differed significantly, yet pH was normal. Phenotypic expression and microparticle content demonstrated no significant differences. FDP units showed a shorter clotting time in ROTEM EXTEM (50 ± 5 vs. 58 ± 9 s, p = .035), although clot strength was similar.

FDP-reconstituted platelets were functionally comparable to those reconstituted with FFP, while demonstrating improved recovery and enhanced clot initiation, potentially due to differences in plasma composition. Given its logistical advantages, particularly in resource-limited settings, FDP represents a promising reconstitution medium for cryopreserved platelets.