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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Blood Component Removal, Blood Donors, Blood Platelets, Cell Survival, Cell-Derived Microparticles, Cryopreservation, Dimethyl Sulfoxide, Enzyme-Linked Immunosorbent Assay, Flow Cytometry, Freezing, Humans, Platelet-Derived Growth Factor, Thrombin Time.
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Does generation of Platelet Microparticles After Cryopreservation of Apheresis Platelet concentrate Contribute to the Hemostatic Activity? Context: In the last decade, substantial evidence has accumulated about the use of cryopreserved platelet concentrates, especially in trauma. However, little reference has been made in these studies about the morphological and functional changes of platelets. Recently, platelets have been shown to be activated by cryopreservation process and to undergo pro-coagulant membrane changes resulted in the generation of platelet derived microparticles (PMPs), platelet degranulation, and release of platelet-derived growth factors (PDGFs). We assessed viabilities, PMP and PDGF levels of cryopreserved platelets and their relation with thrombin generation. Apheresis platelet concentrates (APCs) from 20 donors have been stored for one day and cryopreserved with 6% dimethyl sulfoxide. Cryopreserved APCs were kept at -80 0C for one day. Thawed 100 ml of APCs were diluted with 20 mL of autologous plasma and specimens were analyzed for viabilities and PMPs by flow cytometry, for thrombin generation by Calibrated Automated Thrombogram and for PDGFs by ELISA test. The mean PMP and PDGF levels in freeze thawed APCs were significantly higher (2763±399,4/µL vs 319,9±80,5/µL;p<.001 and 550,9±73.6 pg/mL vs 96,5±49 pg/mL; p<.001 respectively), but the viability ratios were significantly lower (68,2±13,7% vs 94±7,5%; p <.001) than fresh APCs. The mean endogenous thrombin potential (ETP) of freeze thawed APCs were significantly higher than the fresh APCs (3406,1±430,4 nM.min. vs 2757,6±485,7 nM.min.,p <.001). Moreover, there were a significant positive correlation between ETP levels and PMP levels (r: 192, p=.014).
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Our results showed that, after cryopreservation, while levels of PMPs were increasing, significantly higher and earlier thrombin formation was occurring in the samples analysed, despite the significant decrease in the viability. Considering the damage caused by the freezing process and the scarcity of evidence for their in vivo superiority, frozen platelets shall be considered for use in austere environments, reserving fresh platelets for prophylactic use in blood banks. Final Decision: yes