A paired comparison of thawed and liquid plasma.

BACKGROUND: To make plasma readily available to treat major hemorrhage, some centers are internationally using either thawed plasma (TP) or "never-frozen" liquid plasma (LP). Despite the routine use of both, there are limited data comparing the two. The hemostatic properties of LP were evaluated and compared to TP in a paired study. STUDY DESIGN AND METHODS: Two ABO-matched plasma units were pooled and split to produce 1 unit for LP and 1 unit for TP. Samples of TP and LP, stored at 2 to 6°C, were tested for a range of coagulation factors, thrombin generation, and rotational thromboelastometry. An additional 119 units of LP were collected and analyzed for markers of contact activation (S-2302 cleavage) and cellular content. RESULTS: LP and TP were compared, up to 7 days of storage, with results showing no difference in the rate of change over time for any variable measured. When compared to Day 5, LP on Day 7 showed no difference for any factors measured; however, on Day 11 Factor (F)II, FV, FVII, and protein S (activity) were lower. Analysis of 119 LP units showed that 26 of 119 (22%) exhibited cold-induced contact activation by Day 28. CONCLUSION: LP and TP were comparable in terms of hemostatic variables up to 7 days of storage. Decreasing coagulation factor activity along with an increased activation risk during storage of LP needs to be balanced against availability to supply and clinical need when considering using LP with more than 7 days of storage.

The hemostatic properties of thawed pooled cryoprecipitate up to 72 hours.

BACKGROUND: There is increasing interest in replacing fibrinogen early for the treatment of major hemorrhage. In countries where cryoprecipitate is the main concentrated source of fibrinogen, the thawing process complicates the timely availability of cryoprecipitate for transfusion early during major bleeding. The aim of the study was to investigate the hemostatic quality of cryoprecipitate, thawed and held at 18 to 24°C for up to 72 hours. STUDY DESIGN AND METHODS: Pooled cryoprecipitate (16 units [eight group O and eight group A]) were thawed at 35 ± 2°C for 20 minutes and held at ambient temperature (18-24°C) for up to 72 hours. Samples were tested at 0, 4, 10, 24, 48, and 72 hours after thawing for Factor (F)VIII, fibrinogen activity, FXIII, rotational thromboelastometry (ROTEM), and thrombin generation (TG). RESULTS: There were no significant changes in levels of fibrinogen and FXIII over 72 hours. There was a significant decrease (p < 0.001) in FVIII at 24, 48, and 72 hours compared with the baseline; however, at all time points units met the UK specification for FVIII level. The peak thrombin, endogenous thrombin potential, and all ROTEM variables remained unchanged after 72 hours. CONCLUSIONS: The hemostatic properties of thawed pooled cryoprecipitate, maintained at ambient temperature, remain stable for up to 72 hours. Stocking a prethawed product may optimize inventory management, to ensure product availability for rapid transfusion. Further studies need to assess the potential risk of bacterial contamination arising from storage at ambient temperature to determine the maximum shelf life for cryoprecipitate after thawing.

Effects of riboflavin and amotosalen photoactivation systems for pathogen inactivation of fresh-frozen plasma on fibrin clot structure.

BACKGROUND: Fresh-frozen plasma (FFP) transfusion carries a risk of viral transmission from donor to recipient. Riboflavin (Mirasol) and amotosalen (Intercept) are two pathogen inactivation (PI) methods that may enhance the safety of FFP for transfusion. Our study investigated the effects of Mirasol and Intercept treatment on fibrin formation and clot structure. STUDY DESIGN AND METHODS: FFP underwent either Mirasol or Intercept treatment, and aliquots were taken before addition of the compound, before illumination (after addition of compound only), and after treatment (addition of compound plus illumination). All samples underwent turbidimetric analysis, lysis analysis, assessment of clot permeation, and analysis by laser scanning confocal microscopy. RESULTS: After treatment, there was a decrease in optical density of the fibrin network for Mirasol and Intercept, lag time to fibrin formation was prolonged for Mirasol and lysis time for Intercept, clot permeability was significantly decreased, and clot density was increased for both. CONCLUSIONS: Our study shows that plasma treated with Mirasol and Intercept produces denser clots consisting of thinner fibers and warrants further studies to evaluate the clinical significance of these structural changes in fibrin clot formation.