No abstract

Background: The Netherlands Armed Forces (NLAF) are using À80°C deepfrozen thrombocyte concentrate (DTC) since 2001. The aim of this study is to investigate the effect of storage duration and alterations in production/ measurement techniques on DTC quality. It is expected that DTC quality is unaffected by storage duration and in compliance with the European guidelines for fresh and cryopreserved platelets. Study Design and Methods: Pre-freeze and post-thaw product platelet content and recovery were collected to analyze the effects of dimethyl sulfoxide (DMSO) type, duration of frozen storage (DMSO-1 max 12 years and DMSO-2 frozen DTC max 4 years at À80°C) and type of plasma used to suspend DTC. Coagulation characteristics of thawed DTC, plasma and supernatant of DTC (2Â 2500 G) were measured with Kaolin thromboelastography (TEG) and phospholipid (PPL) activity assay.Results: Platelet content and recovery of DTC is ±10%-15% lower in shortstored products and remained stable when stored beyond 0.5 years. Thawed DTC (n = 1724) were compliant to the European guidelines (98.1% post-thaw product recovery ≥50% from original product, 98.3% ≥200 Â 10 9 platelets/ unit). Compared to DMSO-1, products frozen with DMSO-2 showed ±8% reduced thaw-freeze recovery, a higher TEG clot strength (MA 58 [6] vs. 64 [8] mm) and same ±11 s PPL clotting time. The use of cold-stored thawed plasma instead of fresh thawed plasma did not influence product recovery or TEG-MA.

BACKGROUND: Early plasma transfusion is important in the treatment of patients with major hemorrhage. Prolonged shelf life of AB type frozen −80°C and coldstored (4°C) deep frozen plasma (DFP) will improve strategic stock management, minimize need for resupply, and make pre-hospital implementation more feasible. METHODS AND MATERIALS: Plasma products type AB of different age and origin (−30°C Fresh Frozen [(FFP], −80°C DFP [short (AE1 year) and long (AE7 year)] stored) were thawed (Day 0), stored at 4°C, and sampled on Days 7 and 14. Additionally, samples of plasma containing blood products (Octaplas LG ® , whole blood and platelets) were compared for coagulation factor activity, phospholipid clotting time (PPL), and kaolin TEG during 4°C or 22°C storage. RESULTS: Coagulation profiles of FFP, short-and longstored −80°C DFP were not significantly different after thaw. Cold storage did not affect fibrinogen, Protein C, and Antithrombin III activities whereas factor V, VII, VIII, and Protein S decreased in all blood products. After 14 days DFP still meets the guidelines for clinical use, except for Protein S (0.4 IU/mL). With exception of Octaplas LG ® , phospholipid activity and TEG coagulation were similar between plasma containing blood components during storage. CONCLUSION: AB DFP quality was unaffected by almost 7 years of frozen storage. Quality of thawed 14day stored AB DFP met, with exception of Protein S, all minimal guidelines which implies that its quality is sufficient for use in the (pre)-hospital (military) environment for treatment of major hemorrhage.