Background
Platelets are a key component of massive transfusion in treating actively bleeding patients. While optimized for prophylactic transfusions, the effectiveness of the current standard room ...temperature stored platelets (RPs) in treating actively bleeding patients is not clear. Cold‐stored platelets (CPs) have been shown to have superior hemostatic functions and the potential to extend shelf life. In this study, we explored the effect of using CPs versus RPs in an in vitro transfusion model based on the massive transfusion protocol.
Study Design and Methods
RPs or CPs were combined with RBCs and plasma in a 1:1:1 volume ratio to make transfusion packages. Whole blood was collected and then either diluted to 20% hematocrit or mixed with tPA (8.8 μg/ml). By volume, 70% of transfusion package was mixed with 30% whole blood to simulate massive transfusions and analyzed by rotational thromboelastometry. Transfusion package supernatant was analyzed for PAI‐1 activity as well.
Results
Both transfusion packages restored the clot characteristics of hemodiluted or hyperfibrinolytic whole blood. Specifically, only transfusion packages made with CPs significantly reduced the maximum clot lysis of hyperfibrinolytic whole blood. PAI‐1 activity in CPs transfusion packages were also significantly higher.
Discussion
Transfusion packages containing cold‐stored platelets may be able to restore the blood hemostatic profile of bleeding patients. In addition, transfusion packages made from CPs may provide additional benefit of resisting hyperfibrinolysis in bleeding patients. In trauma where post‐transfusion platelet recovery is less of a concern, CPs are a viable option to restore hemostasis.
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•Storage-related changes were identified in Red Cell Concentrate using SORS.•MuSCA was employed to assess Raman data against parallel bioanalytical measurements.•Spectral markers ...strongly correlated with respective bioassays in RCC were revealed.•Our approach enabled direct quality monitoring of RCC within sealed transfusion bags.
In this work we employ Spatially Offset Raman Spectroscopy (SORS) to non-invasively identify storage-related changes in red blood cell concentrate (RCC) in-situ within standard plastic transfusion bags. To validate the measurements, we set up a parallel study comparing both bioanalytical data (obtained by blood-gas analysis, hematology analysis and spectrophotometric assays), and Raman spectrometry data from the same blood samples. We then employ Multisource Correlation Analysis (MuSCA) to correlate the different types of data in RCC. Our analysis confirmed a strong correlation of glucose, methemoglobin and oxyhemoglobin with their respective bioassay values in RCC units. Finally, by combining MuSCA with k-means clustering, we assessed changes in all Raman wavenumbers during cold storage in both RCC Raman data from the current study and parallel RCC supernatant Raman data previously acquired from the same units. Direct RCC quality monitoring during storage, would help to establish a basis for improved inventory management of blood products in blood banks and hospitals based on analytical data.
Background
Fetal and neonatal exposure to lead is associated with irreversible adverse effects on neural development. There is no reliable threshold for lead effect, so limiting exposure is ...recommended. A significant correlation has been reported between post‐transfusion blood lead level (BLL) in infants and lead levels in transfused RBC units. We measured levels of lead, mercury, and cadmium, in Canadian donor blood to investigate if concerning levels for neonatal transfusion exist.
Study Design and Methods
Whole blood samples from blood donors (n = 2529) were shipped cold within 7 days of donation. All permanent blood donation clinics across Canada were sampled. Twelve of these permanent clinics and 8 mobile clinics with a greater potential for having higher lead or mercury levels were oversampled. Heavy metals were measured by inductively coupled plasma mass spectrometry.
Results
Of all donations, 2.2% (lead) and 0.4% (mercury) had levels higher than the recommended thresholds for safe neonatal transfusion. BLLs were higher in males but there was no significant difference in the blood mercury levels of males versus females. Cadmium levels were higher in females. There was a positive correlation between donor age and levels of heavy metals, with lead having the strongest correlation (r = 0.47, p < .0001). Three clinics in close proximity to two lead‐producing mines were among the clinics with the highest BLLs. Significantly higher blood mercury levels were observed in coastal clinics.
Conclusion
Our data on donor blood heavy metal levels supports considering blood transfusion as an exposure source to heavy metals and encourages informed selection of blood units for transfusion to vulnerable groups.
Background
Randomized clinical trial data show that early plasma transfusion may save lives among trauma patients. Supplying plasma in remote environments is logistically challenging. Freeze‐dried ...plasma (FDP) offers a possible solution.
Study Design and Methods
A Terumo BCT plasma freeze‐drying system was evaluated. We compared pooled frozen plasma (FP) units with derived Terumo BCT FDP (TFDP) units and pooled COVID‐19 convalescent apheresis fresh‐frozen plasma (CC‐AFFP) with derived CC‐TFDP units. Parameters measured were: coagulation factors (F) II; V; VII; VIII; IX; XI; XIII; fibrinogen; Proteins C (PC) and S (PS); antithrombin (AT); α2‐antiplasmin (α2AP); ADAMTS13; von Willebrand Factor (vWF); thrombin–antithrombin (TAT); D‐dimer; activated complement factors 3 (C3a) and 5 (C5a); pH; osmolality; prothrombin time (PT); and activated partial thromboplastin time (aPTT). Antibodies to SARS‐CoV‐2 in CC‐AFFP and CC‐TFDP units were compared by plaque reduction assays and viral protein immunoassays.
Results
Most parameters were unchanged in TFDP versus FP or differed ≤15%. Mean aPTT, PT, C3a, and pH were elevated 5.9%, 6.9%, 64%, and 0.28 units, respectively, versus FP. CC‐TFDP showed no loss of SARS‐CoV‐2 neutralization titer versus CC‐AFFP and no mean signal loss in most pools by viral protein immunoassays.
Conclusion
Changes in protein activities or clotting times arising from freeze‐drying were <15%. Although C3a levels in TFDP were elevated, they were less than literature values for transfusable plasma. SARS‐CoV‐2‐neutralizing antibody titers and viral protein binding levels were largely unaffected by freeze‐drying. In vitro characteristics of TFDP or CC‐TFDP were comparable to their originating plasma, making future clinical studies appropriate.
See editorial on page 257–260, in this issue
Background
The use of whole blood (WB) to treat trauma patients is becoming more common. Similar to the treatment of individual components, pathogen inactivation (PI) technologies are available to ...treat WB. The impact of PI on WB function is not well understood. This study investigated the impact of PI of WB with riboflavin/ultraviolet (UV) light on its hemostatic function by modeling transfusion scenarios for trauma patients and assessing transfusion efficacy by rotational thromboelastometry (ROTEM). As fibrinogen is affected by PI of WB, the effect of fibrinogen supplementation commonly used in trauma patients was also analyzed in this model.
Study Design and Methods
Trauma transfusion scenarios were simulated by mixing untreated WB or WB treated with the Mirasol PI technology (riboflavin/UV) in different ratios with hemodiluted blood, and the thromboelasticity was monitored by ROTEM. The impact of supplementation with the fibrinogen concentrate RiaSTAP was investigated in this model.
Results
Pathogen‐inactivated WB (PI‐WB) showed decreased activity in the hemostatic profile compared to the untreated control. Hemodiluted blood at a hematocrit (hct) of 20%, which was reconstituted with PI‐WB or untreated WB, exhibited increased alpha values, maximum clot firmness, and clot formation time. Simulating transfusion scenarios by blood replacement with PI‐WB resulted in a significant difference in ROTEM parameters between reconstituted PI‐treated and ‐untreated WB (p ≥ .05). The effect of PI treatment waned when PI‐WB was enriched with fibrinogen.
Conclusion
ROTEM investigations suggest that PI treatment has a negative impact on WB clot formation unless fibrinogen supplementation is used.
Abstract Pathogen inactivation (PI) of platelet concentrates (PCs) reduces the proliferation/replication of a large range of bacteria, viruses, and parasites as well as residual leucocytes. ...Pathogen-inactivated PCs were evaluated in various clinical trials showing their efficacy and safety. Today, there is some debate over the hemostatic activity of treated PCs as the overall survival of PI platelets seems to be somewhat reduced, and in vitro measurements have identified some alterations in platelet function. Although the specific lesions resulting from PI of PCs are still not fully understood, proteomic studies have revealed potential damages at the protein level. This review merges the key findings of the proteomic analyses of PCs treated by the Mirasol Pathogen Reduction Technology, the Intercept Blood System, and the Theraflex UV-C system, respectively, and discusses the potential impact on the biological functions of platelets. The complementarities of the applied proteomic approaches allow the coverage of a wide range of proteins and provide a comprehensive overview of PI-mediated protein damage. It emerges that there is a relatively weak impact of PI on the overall proteome of platelets. However, some data show that the different PI treatments lead to an acceleration of platelet storage lesions, which is in agreement with the current model of platelet storage lesion in pathogen-inactivated PCs. Overall, the impact of the PI treatment on the proteome appears to be different among the PI systems. Mirasol impacts adhesion and platelet shape change, whereas Intercept seems to impact proteins of intracellular platelet activation pathways. Theraflex influences platelet shape change and aggregation, but the data reported to date are limited. This information provides the basis to understand the impact of different PI on the molecular mechanisms of platelet function. Moreover, these data may serve as basis for future developments of PI technologies for PCs. Further studies should address the impact of both the PI and the storage duration on platelets in PCs because PI may enable the extension of the shelf life of PCs by reducing the bacterial contamination risk.
Formal processes to assess risk are well established in numerous areas of society including the environment, transportation, energy and food production sectors as well as some areas of health care ...such as new drugs or other therapeutic goods. However, these processes and their associated frameworks have only recently come to be used to make decisions in blood transfusion practice or in blood system policy development. This review describes the evolution of the use of risk‐based decision making and discusses the elements that should be considered in its application to blood system issues. Following the identification and characterization of the risk, a structured process is undertaken to assess the magnitude of the risk and the level of risk reduction that can reasonably be achieved in the context of the complexity of the risk management action proposed and its cost. Inputs must be sought from appropriate subject matter experts, but also from those who can consider issues of ethics and social values. Engagement of the public is an essential step. Proposed interventions should be assessed for their likelihood of mitigating the risk and the proportional resource allocation in comparison with similar risks to the blood system or health system. Examples are provided of how a risk‐based decision‐making framework is used to address identified risks in the blood system.
Background
Leukoreduced whole blood (LR‐WB) has received renewed attention as alternative to component‐based transfusion in trauma. According to the manufacturer's instructions, leukoreduction should ...be carried out within 8 h after collection. This study assessed impact of (1) WB collection bag, (2) LR filtration, and (3) timing of filtration on in vitro quality.
Study Design and Methods
WB collected into different vendor bags was held at room temperature for <8 h or >16 h but <24 h prior to LR. In vitro quality was assessed before and after filtration, and throughout 3 weeks of storage at 4°C. Cell count and hemoglobin levels were determined by hematology analyzer, platelet activation, and responsiveness to ADP by surface expression of P‐selectin by flow cytometry, hemolysis by HemoCue, and metabolic parameters by blood gas analyzer. Hemostatic properties were assessed by rotational thromboelastometry. Plasma protein activities and clotting times were determined by automated coagulation analyzer or quantitative immunoblotting.
Results
Bag type had no impact on WB in vitro quality. LR by filtration had some impact, but is aligned with data in the literature. The time between donation and filtration resulted in some statistically significant differences in metabolic activity, platelet yield, platelet activation, and factor protein activity initially; however, these differences in in vitro quality attributes decreased throughout 21‐day cold storage.
Conclusion
WB hold time showed only a minor impact on WB in vitro quality, so it may be possible for blood processing facilities to explore extended hold times prior to filtration in order to provide greater operational flexibility.
Background
Pathogen inactivation (PI) accelerates the platelet (PLT) storage lesion, including apoptotic‐like changes. Proteomic studies have shown that phosphorylation levels of several kinases ...increase in PLTs after riboflavin and UV light (RF‐PI) treatment. Inhibition of p38MAPK improved in vitro PLT quality, but the biochemical basis of this kinase's contribution to PLT damage requires further analysis.
Study Design and Methods
In a pool‐and‐split design, apheresis PLT concentrates were either treated or kept untreated with or without selected kinase inhibitors. Samples were analyzed throughout 7 days of storage, monitoring in vitro quality variables including phosphatidylserine exposure, degranulation, and glucose metabolism. Changes in the protein expression of Bax, Bak, and Bcl‐xL and the activities of caspase‐3 and ‐9 were determined by immunoblot analysis and flow cytometry, respectively.
Results
The expression levels of the proapoptotic proteins Bax and Bak, but not the antiapoptotic protein Bcl‐xL, were significantly increased after the RF‐PI treatment. This trend was reversed in the presence of p38MAPK inhibitor SB203580. As a result of increasing proapoptotic protein levels, caspase‐3 and ‐9 activities were significantly increased in RF‐PI treatment during storage compared with control (p < 0.05). Similarly, p38MAPK inhibition significantly reduced these caspase activities compared with vehicle control after RF‐PI treatment (p < 0.05).
Conclusion
These findings revealed that p38MAPK is involved in signaling leading to apoptosis triggered by RF‐PI. Elucidation of the biochemical processes influenced by PI is a necessary step in the development of strategies to improve the PLT quality and ameliorate the negative effects of PI treatment.
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