All plasma products are not created equal: Characterizing differences between plasma products

Expanded use of liquid plasma in non-emergency transfusions: A single academic institution experience

BACKGROUND

Liquid plasma (LP) is isolated from whole blood donations, never frozen, and can be immediately transfused. Its primary indication is initial treatment of patients undergoing massive transfusion. To minimize wastage of this resource, we expanded the use of LP to include surgical and routine transfusions.

METHODS

Our medical record was queried for plasma transfusions with at least one unit of LP issued. Chart review identified the indications for transfusion (emergency use, surgical use, or routine transfusion) and assessed effects of LP on coagulopathy, the use of additional blood products, and mortality. LP cases were categorized into two groups based on the fraction of LP transfused (≤50% or >50% LP). A control group of routine transfusion using only thawed plasma (TP) was reviewed and statistically compared to those cases where LP was included.

RESULTS

Eight hundred ninety cases were studied including 34% emergency/massive transfusion events, 44% surgical cases, and 11% routine transfusions. In surgeries using LP, there were no significant differences in outcomes based on higher fractions of LP transfused. The correction of coagulopathy, the need for additional blood products, and the encounter-specific mortality were consistent across both routine transfusions with higher fractions of LP and comparing LP transfusion events to control TP transfusion events.

CONCLUSION

The utilization of LP in surgical cases and routine plasma transfusions was not associated with worse clinical outcomes and effectively prevented product waste. This report supports the broader use of and further study of LP in patient care.

Viability of Plasmodium falciparum parasites in human plasma under different storage conditions

BACKGROUND AND OBJECTIVES

Malaria risk deferral policies are important for mitigating the risk of transfusion-transmitted malaria and apply to all transfusable components, including plasma. While donors of plasma components are deferred for malaria risk in the United States, the viability of intraerythrocytic Plasmodium falciparum parasites present in human plasma components stored under different temperatures and durations has not been previously reported.

MATERIALS AND METHODS

We spiked human plasma with a low level of ring-stage P. falciparum-infected red blood cells and then determined their viability in cultures after storage at room temperature (22°C), refrigeration (4°C) and frozen conditions at -20 and -80°C.

RESULTS

P. falciparum parasites spiked in human plasma remained viable after storage at 22°C for a maximum of 7 days. When stored at 4°C, parasites were viable after 1 and 3 days of storage and only for 1 day after storage at -20°C. Storage at -80°C had a cryopreserving effect and parasites remained viable for up to 176 days, the longest period tested.

CONCLUSION

P. falciparum parasites can survive for short durations in human plasma when stored at room temperature, or in refrigerated or frozen conditions at -20°C. However, when stored at -80°C, viable parasites were detected for up to 176 days, the maximum duration for which viability was assessed. In summary, Plasmodium parasites can survive in human plasma under different storage conditions and pose a risk of transfusion-transmitted infection.

Dried Plasma for Major Trauma: Past, Present, and Future

Uncontrollable bleeding is recognized as the leading cause of preventable death among trauma patients. Early transfusion of blood products, especially plasma replacing crystalloid and colloid solutions, has been shown to increase survival of severely injured patients. However, the requirements for cold storage and thawing processes prior to transfusion present significant logistical challenges in prehospital and remote areas, resulting in a considerable delay in receiving thawed or liquid plasma, even in hospitals. In contrast, freeze- or spray-dried plasma, which can be massively produced, stockpiled, and stored at room temperature, is easily carried and can be reconstituted for transfusion in minutes, provides a promising alternative. Drawn from history, this paper provides a review of different forms of dried plasma with a focus on in vitro characterization of hemostatic properties, to assess the effects of the drying process, storage conditions in dry form and after reconstitution, their distinct safety and/or efficacy profiles currently in different phases of development, and to discuss the current expectations of these products in the context of recent preclinical and clinical trials. Future research directions are presented as well.

Hemostatic In Vitro Properties of Novel Plasma Supernatants Produced from Late-storage Low-titer Type O Whole Blood

BACKGROUND

The use of low-titer group O whole blood is increasing. To reduce wastage, unused units can be converted to packed red blood cells. Supernatant is currently discarded post-conversion; however, it could be a valuable transfusable product. The aim of this study was to evaluate supernatant prepared from late-storage low-titer group O whole blood being converted to red blood cells, hypothesizing it will have higher hemostatic activity compared to fresh never-frozen liquid plasma.

METHODS

Low-titer group O whole blood supernatant (n = 12) prepared on storage day 15 was tested on days 15, 21, and 26 and liquid plasma (n = 12) on 3, 15, 21, and 26. Same-day assays included cell counts, rotational thromboelastometry, and thrombin generation. Centrifuged plasma from units was banked for microparticle characterization, conventional coagulation, clot structure, hemoglobin, and additional thrombin generation assays.

RESULTS

Low-titer group O whole blood supernatant contained more residual platelets and microparticles compared to liquid plasma. At day 15, low-titer group O whole blood supernatant elicited a faster intrinsic clotting time compared to liquid plasma (257 ± 41 vs. 299 ± 36 s, P = 0.044), and increased clot firmness (49 ± 9 vs. 28 ± 5 mm, P < 0.0001). Low-titer group O whole blood supernatant showed more significant thrombin generation compared to liquid plasma (day 15 endogenous thrombin potential 1,071 ± 315 vs. 285 ± 221 nM·min, P < 0.0001). Flow cytometry demonstrated low-titer group O whole blood supernatant contained significantly more phosphatidylserine and CD41+ microparticles. However, thrombin generation in isolated plasma suggested residual platelets in low-titer group O whole blood supernatant were a greater contributor than microparticles. Additionally, low-titer group O whole blood supernatant and liquid plasma showed no difference in clot structure, despite higher CD61+ microparticle presence.

CONCLUSIONS

Plasma supernatant produced from late-storage low-titer group O whole blood shows comparable, if not enhanced, in vitro hemostatic efficacy to liquid plasma.

EDITOR’S PERSPECTIVE

Transfusion of hyperimmune plasma for protecting foals against Rhodococcus equi pneumonia

The bacterium Rhodococcus equi causes pneumonia in foals that is prevalent at breeding farms worldwide. In the absence of an effective vaccine, transfusion of commercial plasma from donor horses hyperimmunised against R. equi is used by many farms to reduce the incidence of pneumonia among foals at farms where the disease is endemic. The effectiveness of hyperimmune plasma for controlling R. equi pneumonia in foals has varied considerably among reports. The purposes of this narrative review are: 1) to review early studies that provided a foundational basis for the practice of transfusion of hyperimmune plasma that is widespread in the US and in many other countries; 2) to summarise current knowledge of hyperimmune plasma for preventing R. equi pneumonia; 3) to provide an interpretive summary of probable explanations for the variable results among studies evaluating the effectiveness of transfusion of hyperimmune plasma for reducing the incidence of R. equi pneumonia; 4) to review mechanisms by which hyperimmune plasma might mediate protection; and 5) to consider risks of transfusing foals with hyperimmune plasma. Although the weight of evidence supports the practice of transfusing foals with hyperimmune plasma to prevent R. equi pneumonia, many important gaps in our knowledge of this topic remain including the volume/dose of hyperimmune plasma to be transfused, the timing(s) of transfusion, and the mechanism(s) by which hyperimmune plasma mediates protection. Transfusing foals with hyperimmune plasma is expensive, labour-intensive, and carries risks for foals; therefore, alternative approaches for passive and active immunisation to prevent R. equi pneumonia are greatly needed. This article is protected by copyright. All rights reserved.

Targeting repair of the vascular endothelium and glycocalyx after traumatic injury with plasma and platelet resuscitation

•

Endothelial glycocalyx shedding is a key instigator of the endotheliopathy of trauma.

•

Plasma and platelet transfusions preserve vascular integrity in pre-clinical models.

•

However, platelets may be less effective than plasma in preserving the glycocalyx.

Severely injured patients with hemorrhagic shock can develop endothelial dysfunction, systemic inflammation, and coagulation disturbances collectively known as the endotheliopathy of trauma (EOT). Shedding of the endothelial glycocalyx occurs early after injury, contributes to breakdown of the vascular barrier, and plays a critical role in the pathogenesis of multiple organ dysfunction, leading to poor outcomes in trauma patients. In this review we discuss (i) the pathophysiology of endothelial glycocalyx and vascular barrier breakdown following hemorrhagic shock and trauma, and (ii) the role of plasma and platelet transfusion in maintaining the glycocalyx and vascular endothelial integrity.

Hemostatic Activity of Canine Never-Frozen Liquid Plasma Collected for Transfusion

This study measured the changes of hemostatic activity in liquid plasma (LP) over 7 days of storage. Five canine plasma units, divided into two aliquots were evaluated: one stored refrigerated at 2–6°C as never-frozen LP and one frozen at −18°C as fresh frozen plasma (FFP). Clotting times, coagulation activities of factor (F) V, VIII, X, XI, antithrombin (AT), and von Willebrand (vWF), fibrinogen and D-dimers (DD) content were assessed before storage (baseline value), and after 12, 24, 48 h and 7 days (D7) in LP stored refrigerated, and on day 7 in FFP. At baseline median values of all factor activity were greater than 80%, and for clotting times, AT, fibrinogen and DD content, were within the canine reference range. Some hemostatic parameters changed significantly over 7 days and at the end of storage in LP. However, median activities of FV, FVIII, FX and FXI, coagulation time, AT, fibrinogen and DD content remained within reference ranges at all time points. The only exception was for vWF which median activity was lower than reference range for all storage time points. Activity of FVIII was significant lower in LP at D7 when compared to activity in FFP, with values of 62 vs. 118%, respectively. DD content showed a median value higher than reference range in FFP at D7. Despite some statistically significant changes at the end of 7-day storage period, never-frozen LP maintained median factor activities >80% for most factors. The clinical impact of the drop over time of vWF activity is unknown.

What Laboratory Tests and Physiologic Triggers Should Guide the Decision to Administer a Platelet or Plasma Transfusion in Critically Ill Children and What Product Attributes Are Optimal to Guide Specific Product Selection? From the Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding

OBJECTIVES

To present consensus statements and supporting literature for plasma and platelet product variables and related laboratory testing for transfusions in general critically ill children from the Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding.

DESIGN

Systematic review and consensus conference of international, multidisciplinary experts in platelet and plasma transfusion management of critically ill children.

SETTING

Not applicable.

PATIENTS

Critically ill pediatric patients at risk of bleeding and receiving plasma and/or platelet transfusions.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A panel of 10 experts developed evidence-based and, when evidence was insufficient, expert-based statements for laboratory testing and blood product attributes for platelet and plasma transfusions. These statements were reviewed and ratified by the 29 Transfusion and Anemia EXpertise Initiative - Control/Avoidance of Bleeding experts. A systematic review was conducted using MEDLINE, EMBASE, and Cochrane Library databases, from inception to December 2020. Consensus was obtained using the Research and Development/University of California, Los Angeles Appropriateness Method. Results were summarized using the Grading of Recommendations Assessment, Development, and Evaluation method. We developed five expert consensus statements and two recommendations in answer to two questions: what laboratory tests and physiologic triggers should guide the decision to administer a platelet or plasma transfusion in critically ill children; and what product attributes are optimal to guide specific product selection?

CONCLUSIONS

The Transfusion and Anemia EXpertise Initiative-Control/Avoidance of Bleeding program provides some guidance and expert consensus for the laboratory and blood product attributes used for decision-making for plasma and platelet transfusions in critically ill pediatric patients.

Safety and tolerability of solvent/detergent‐treated plasma for pediatric patients requiring therapeutic plasma exchange: An open‐label, multicenter, postmarketing study

Background

This study investigated the real‐world safety and tolerability of solvent/detergent‐treated (S/D) plasma for pediatric patients requiring therapeutic plasma exchange (TPE).

Study design and methods

LAS‐213 was a multicenter, open‐label, interventional, phase 4 study. Patients (≥2 to ≤20 years) receiving TPE therapy were eligible. A total plasma volume of 40–60 ml/kg was recommended, with an infusion rate not exceeding 0.020–0.025 citrate/kg body weight/min (<1 ml/kg body weight/min). The primary endpoint was assessment of safety, monitoring the following: serious adverse events (SAEs), adverse drug reactions (ADRs), thrombotic events (TEs), thromboembolic events (TEEs), and specific laboratory tests.

Results

In total, 41 children (2 to <12 years [n = 15]; 12 to <17 years [n = 13]; ≥17 years [n = 13]) underwent 102 TPEs with a total of 135,137 ml of S/D plasma exchanged. Each patient group received between 1 and 6 TPEs (mean: 2.5 TPEs). Actual dose administered per TPE was 4–72 ml/kg (mean: 28.6 ml/kg), with a mean total volume of 1324.9 ml (range: 113–4000 ml). Overall safety was excellent for 96/102 (94.0%) TPEs. Six TPEs had a “moderate” safety profile for four patients experiencing eight ADRs. Of these, seven were mild in intensity and one (pyrexia) was moderate, all resolving by study end. Mild citrate toxicity (n = 2) was the most common ADR. One SAE was reported but was unrelated to the study drug. No TEs, TEEs, or changes in laboratory safety parameters were reported.

Conclusion

S/D plasma was well tolerated and demonstrated favorable safety, supporting the use of S/D plasma for TPE in pediatrics.

Ex vivo hemostatic and immuno-inflammatory profiles of freeze-dried plasma

BACKGROUND

Hemorrhage is a leading cause of preventable death in civilian and military trauma. Freeze-dried plasma is promising for hemostatic resuscitation in remote prehospital settings, given its potential benefits in reducing blood loss and mortality, long storage at ambient temperatures, high portability, and rapid reconstitution for transfusion in austere environments. Here we assess the ex vivo characteristics of a novel Terumo's freeze-dried plasma product (TFDP).

STUDY DESIGN AND METHODS

Rotational thromboelastometry (ROTEM) tests (INTEM, EXTEM, and FIBTEM) were conducted on plasma samples at 37°C with a ROTEM delta-machine using standard reagents and procedures. The following samples were analyzed: pooled plasma to produce TFDP, TFDP reconstituted, and stored immediately at -80°C, reconstituted TFDP stored at 4°C for 24 h and room temperature (RT) for 4 h before freezing at -80°C. Analysis of plasma concentrations of selected cytokines, chemokines, and vascular molecules was performed using a multiplex immunoassay system. One-way ANOVA with post hoc tests assessed differences in hemostatic and inflammatory properties.

RESULTS

No significant differences in ROTEM variables (coagulation time [CT], clot formation time, α-angle, maximum clot firmness, and lysis index 30) between the TFDP-producing plasma and reconstituted TFDP samples were observed. Compared to control plasma, reconstituted TFDP stored at 4°C for 24 h or RT for 4 h showed a longer INTEM CT. Levels of immuno-inflammatory mediators were similar between frozen plasma and TFDP.

CONCLUSIONS

TFDP is equivalent to frozen plasma with respect to global hemostatic and immuno-inflammatory mediator profiles. Further investigations of TFDP in trauma-induced coagulopathy models and bleeding patients are warranted.

Spray-dried plasma: A post-traumatic blood "bridge" for life-saving resuscitation

Massive bleeding remains a major source of morbidity and mortality worldwide. Recent studies have shed light on the pathophysiology of traumatic-induced coagulopathy and the central role of endotheliopathy. Transfusion therapy has changed dramatically in the last decade with use of red cells and plasma in a 1:1 ratio. The use of early transfusion increases the likelihood of a favorable outcome. Early intervention-preferably less than 60 min of injury-is a major factor in improved survival. Experience with dried plasma products-lyophilized or freeze-dried-in Europe and South Africa has demonstrated both safety and efficacy. Dry plasma products are not available in the United States but several products are in development. Spray-dried plasma contains clinically meaningful levels of coagulation activity and in vitro data suggest robust ability to generate thrombus. The decentralized, blood-center based manufacturing model of spray-dried plasma offers advantages for availability to meet routine and extraordinary demands.

Diagnosis, therapeutic advances, and key recommendations for the management of factor X deficiency

Factor X deficiency is a rare coagulation disorder that can be hereditary or acquired. The typology and severity of the associated bleeding symptoms are highly heterogeneous, adding to the difficulties of diagnosis and management. Evidence-based guidelines and reviews on factor X deficiency are generally limited to publications covering a range of rare bleeding disorders. Here we provide a comprehensive review of the literature on factor X deficiency, focusing on the hereditary form, and discuss the evolution in disease management and the evidence associated with available treatment options. Current recommendations advise clinicians to use single-factor replacement therapy for hereditary disease rather than multifactor therapies such as fresh frozen plasma, cryoprecipitate, and prothrombin complex concentrates. Consensus in treatment guidelines is still urgently needed to ensure optimal management of patients with factor X deficiency across the spectrum of disease severity.

Thawed solvent/detergent-treated plasma demonstrates comparable clinical efficacy to thawed plasma

BACKGROUND

Thawed Plasma (TP), plasma thawed and refrigerated for up to 5 days, is a commonly transfused plasma product. This pilot study was conducted to determine whether Thawed Solvent/Detergent-treated Plasma stored refrigerated for up to 5-days post-thaw (T-S/D) was as efficacious as TP.

STUDY DESIGN AND METHODS

This single institution retrospective cohort analysis evaluated the efficacy of T-S/D in reversing coagulopathies in comparison to TP. Utilizing the institution's electronic medical records, transfusion data were collected in adult patients who received either TP or T-S/D. The primary outcome was the incidence of subsequent transfusions within 24 hours after first dose of either type of plasma. Secondary outcomes included the number of blood products transfused within 24 hours of first-dose plasma, correction of pre-transfusion coagulation laboratory values, volume transfused, and clinical outcomes.

RESULTS

TP was received by 301 patients and 137 received T-S/D during the first 32 months post-implementation of T-S/D. There was no difference in incidence of subsequent transfusions or number of blood products given. The median pre-INR of both the TP and T-S/D cohorts was 1.9, with a similar decrease in INR of 0.2 and 0.3 (p = 0.36), respectively, post plasma transfusion. There was no difference in correction of PT/aPTT, mortality, transfusion reactions, readmission rates, length of stay, or inpatient deep venous thrombosis. The median volume of T-S/D plasma transfused for the first dose was 126 mL less than TP (p = .0001).

CONCLUSION

T-S/D was as efficacious as TP for the treatment of coagulopathies and the reversal of coagulation laboratory values.

Solvent/Detergent-Treated Plasma in the Management of Pediatric Patients Who Require Replacement of Multiple Coagulation Factors: An Open-Label, Multicenter, Post-marketing Study

Background: Octaplas is a solvent/detergent-treated, pooled plasma used for the management of preoperative or bleeding patients who require replacement of single or multiple coagulation factors. The aim of this post-marketing study was to collect real-world data on octaplas treatment in pediatric patients, with the primary focus being safety. Methods: This was an open-label, multicenter, phase IV study conducted in patients <16 years old who required replacement of multiple coagulation factors due to liver dysfunction associated with coagulopathy and/or required cardiac surgery or liver surgery. Octaplas was administered intravenously based on ABO-group compatibility. The primary endpoints included the incidence of serious adverse events (SAEs), adverse drug reactions (ADRs), thrombotic events (TEs), thromboembolic events (TEEs) and hyperfibrinolytic events (HFEs). Results: A total of 50 patients were enrolled (≤2 years old, n = 37; >2 years old, n = 13; female, n = 24) and 49 patients completed the study. Indications for the use of octaplas included planned cardiac surgery (n = 40, 80.0%), liver transplant surgery (n = 5, 10.0%) and liver dysfunction (n = 5, 10.0%). No ADRs, HFEs or treatment-related TEs and TEEs occurred during the study. Five patients had SAEs, one of which was fatal (iatrogenic injury). Other SAEs included hemorrhage, hypotension, hemorrhagic shock, coronary artery hemorrhage, intracardiac thrombus, supraventricular tachycardia, portal vein thrombosis and respiratory failure (1 each). None of the SAEs were considered to be related to octaplas. Conclusions: Results of the present study support the use of octaplas in the management of preoperative or bleeding pediatric patients who require replacement of multiple plasma coagulation factors. Clinical Trial Registration: ClinicalTrials.gov identifier: NCT02050841.

Blood manufacturing methods affect red blood cell product characteristics and immunomodulatory activity

Transfusion of red cell concentrates (RCCs) is associated with increased risk of adverse outcomes that may be affected by different blood manufacturing methods and the presence of extracellular vesicles (EVs). We investigated the effect of different manufacturing methods on hemolysis, residual cells, cell-derived EVs, and immunomodulatory effects on monocyte activity. Thirty-two RCC units produced using whole blood filtration (WBF), red cell filtration (RCF), apheresis-derived (AD), and whole blood-derived (WBD) methods were examined (n = 8 per method). Residual platelet and white blood cells (WBCs) and the concentration, cell of origin, and characterization of EVs in RCC supernatants were assessed in fresh and stored supernatants. Immunomodulatory activity of RCC supernatants was assessed by quantifying monocyte cytokine production capacity in an in vitro transfusion model. RCF units yielded the lowest number of platelet and WBC-derived EVs, whereas the highest number of platelet EVs was in AD (day 5) and in WBD (day 42). The number of small EVs (<200 nm) was greater than large EVs (≥200 nm) in all tested supernatants, and the highest level of small EVs were in AD units. Immunomodulatory activity was mixed, with evidence of both inflammatory and immunosuppressive effects. Monocytes produced more inflammatory interleukin-8 after exposure to fresh WBF or expired WBD supernatants. Exposure to supernatants from AD and WBD RCC suppressed monocyte lipopolysaccharide-induced cytokine production. Manufacturing methods significantly affect RCC unit EV characteristics and are associated with an immunomodulatory effect of RCC supernatants, which may affect the quality and safety of RCCs.

Effect of plasma processing and storage on microparticle abundance, nitric oxide scavenging, and vasoactivity

BACKGROUND

We set out to define the impact of collection, processing, and storage on plasma product microparticle (MP) abundance, potential for nitric oxide (NO) scavenging, and vasoactivity.

STUDY DESIGN AND METHODS

Three currently US licensed products were tested: liquid plasma (LP), fresh frozen plasma (FFP), and solvent detergent plasma (SDP), along with a product under development, spray-dried solvent detergent plasma (SD-SDP) with/without beads. Vasoactivity was assessed in vitro using rabbit aortic vascular rings; MP abundance was determined by flow cytometry; and NO scavenging capacity/rate was determined using a biochemical NO consumption assay. All samples were analyzed unprocessed and following centrifugation at two speeds (2,500× g to remove platelets, and 25,000× g to remove microparticles).

RESULTS

Significant differences in vasoactivity were observed, with SD-SDP minus beads demonstrating the greatest constriction and FFP the lowest constriction response. All products exhibited the same total NO scavenging capacity; however, significant differences were observed in the maximal rate of scavenging, with SD-SDP minus beads and FFP reacting fastest and SDP the slowest. Across all products, platelet and microparticle depletion had no effect on vasoactivity or NO scavenging (total or rate). Microparticles (RBC derived) were found only in FFP and LP, with relative abundance (LP > FFP). Additionally, storage had no effect on total or RBC-derived MP abundance, NO scavenging, or vasoactivity.

CONCLUSION

Although vasoactivity differed between plasma products, we did not find similar differences in either total or RBC-derived MP abundance or NO scavenging capacity/rate.

Damage Control Resuscitation

Damage control resuscitation (DCR) is a strategy for resuscitating patients from hemorrhagic shock to rapidly restore homeostasis. Efforts are focused on blood product transfusion with whole blood or component therapy closely approximating whole blood, limited use of crystalloid to avoid dilutional coagulopathy, hypotensive resuscitation until bleeding control is achieved, empiric use of tranexamic acid, prevention of acidosis and hypothermia, and rapid definitive surgical control of bleeding. Patients receiving uncrossmatched Type O blood in the emergency department and later receiving cumulative transfusions of 10 or more red blood cell units in the initial 24-hour post-injury (massive transfusion) are widely recognized as being at increased risk of morbidity and mortality due to exsanguination. Ideally, these patients should be rapidly identified, however anticipating transfusion needs is challenging. Useful indicators of massive transfusion reviewed in this guideline include: systolic blood pressure <110 mmHg, heart rate > 105 bpm, hematocrit <32%, pH < 7.25, injury pattern (above-the-knee traumatic amputation especially if pelvic injury is present, multi-amputation, clinically obvious penetrating injury to chest or abdomen), >2 regions positive on Focused Assessment with Sonography for Trauma (FAST) scan, lactate concentration on admission >2.5, admission international normalized ratio ≥1.2-1.4, near infrared spectroscopy-derived StO2 < 75% (in practice, rarely available), BD > 6 meq/L. Unique aspects of out-of-hospital DCR (point of injury, en-route, and remote DCR) and in-hospital (Medical Treatment Facilities: Role 2b/Forward surgical teams - role 3/ combat support hospitals) are reviewed in this guideline, along with pediatric considerations.

Dried Plasma

Dried plasma provides an alternative for early plasma transfusion in the resuscitation of hemorrhagic shock in environments where fresh frozen plasma is not immediately available. It is produced by freeze-drying or spray-drying liquid or thawed plasma. It is shelf-stable for prolonged periods, can be stored at room temperature, and is easy to transport, reconstitute, and administer. It was widely used in WWII but fell out of favor due to the risk of infectious disease transmission. The German and French experiences with lyophilized plasma are the most extensive and show a good track record of efficacy and safety. Recent studies show many beneficial effects of dried plasma in the treatment of shock in large animal models. Currently, no FDA-licensed product is available in the USA, but several are under development.

Immunomodulatory effects of plasma products on monocyte function in vitro

BACKGROUND

Restoration of a balanced innate immune response is paramount to recovery from critical injury. Plasma transfusion may modulate innate immune responses; however, little is known about the immunomodulatory potential of various plasma products. We conducted in vitro experiments to determine the effects of fresh frozen plasma, thawed plasma, solvent/detergent plasma, and an investigational spray-dried solvent/detergent plasma product on monocyte function.

METHODS

Monocytes were isolated from healthy adult volunteers and cocultured with aliquots of autologous plasma (control), fresh frozen plasma, thawed plasma, solvent/detergent treated plasma, or spray-dried solvent/detergent plasma. Monocyte function was assessed by cytokine production with and without lipopolysaccharide (LPS) stimulation, and flow cytometric assessment of HLA-DR cell surface expression.

RESULTS

Monocyte cytokine production was not significantly altered after exposure to fresh frozen plasma or thawed plasma. In the absence of LPS, spray-dried solvent/detergent plasma exposure resulted in markedly increased IL-8 production compared to other plasma groups and controls (p = 0.01, analysis of variance [ANOVA]). Likewise, spray-dried SD plasma exposure resulted in higher LPS-induced IL-8, TNFα, and IL-1β production compared with autologous plasma controls (p < 0.0001; p < 0.0001, p = 0.002, respectively; ANOVA). LPS-induced IL-8 and TNFα production was lowest after exposure to solvent/detergent plasma (p < 0.0001, ANOVA).

CONCLUSION

Exposure to spray-dried solvent/detergent plasma resulted in marked augmentation of monocyte inflammatory cytokine production. Solvent/detergent plasma exposure resulted in the lowest cytokine production, suggesting lower immunomodulatory potential. Further work is needed to determine how these in vitro findings may translate to the bedside.

Washing or filtering of blood products does not improve outcome in a rat model of trauma and multiple transfusion

BACKGROUND

Transfusion is associated with organ failure and nosocomial infection in trauma patients, which may be mediated by soluble bioactive substances in blood products, including extracellular vesicles (EVs). We hypothesize that removing EVs, by washing or filtering of blood products, reduces organ failure and improves host immune response.

MATERIALS AND METHODS

Blood products were prepared from syngeneic rat blood. EVs were removed from RBCs and platelets by washing. Plasma was filtered through a 0.22‐μm filter. Rats were traumatized by crush injury to the intestines and liver, and a femur was fractured. Rats were hemorrhaged until a mean arterial pressure of 40 mm Hg and randomized to receive resuscitation with standard or washed/filtered blood products, in a 1:1:1 ratio. Sham controls were not resuscitated. Ex vivo whole blood stimulation tests were performed and histopathology was done.

RESULTS

Washing of blood products improved quality metrics compared to standard products. Also, EV levels reduced by 12% to 77%. The coagulation status, as assessed by thromboelastometry, was deranged in both groups and normalized during transfusion, without significant differences. Use of washed/filtered products did not reduce organ failure, as assessed by histopathologic score and biochemical measurements. Immune response ex vivo was decreased following transfusion compared to sham but did not differ between transfusion groups.

CONCLUSION

Filtering or washing of blood products improved biochemical properties and reduced EV counts, while maintaining coagulation abilities. However, in this trauma and transfusion model, the use of optimized blood components did not attenuate organ injury or immune suppression.

Blood products and procoagulants in traumatic bleeding: use and evidence

PURPOSE OF REVIEW

Death from uncontrolled haemorrhage is one of the leading causes of trauma-related mortality and is potentially preventable. Advances in understanding the mechanisms of trauma-induced coagulopathy (TIC) have focused attention on the role of blood products and procoagulants in mitigating the sequelae of TIC and how these therapies can be improved.

RECENT FINDINGS

A host of preclinical and clinical studies have evaluated blood product availability and efficacy in trauma. Recently published randomized controlled trials have investigated the ratio of platelet:plasma:red cell transfusion and the role of early cryoprecipitate in trauma. Demand for readily available plasma has led to changes particularly in the use of thawed group A plasma. Furthermore, ex-vivo and early clinical work has demonstrated variations in the haemostatic activity of different plasma, platelet and whole blood products. A number of multicentre trials are in progress aiming to answer key questions regarding tranexamic acid, procoagulant factor and fibrinogen concentrates and their effect on trauma outcomes.

SUMMARY

There are promising results from ex-vivo studies in manufacturing and storage of blood products to optimize haemostatic activity and availability, particularly with alternative plasma and platelet products and whole blood. There is an urgent need for these products needs to be tested prospectively.

Characteristics of Extracellular Vesicles in Red Blood Concentrates Change with Storage Time and Blood Manufacturing Method

Background

Extracellular vesicles (EVs) in blood products are potential effectors of inflammation and coagulation after transfusion. The aim of this study was to assess the impact of different blood manufacturing methods and duration of hypothermic storage on the EV subpopulations in relation to other in vitro quality parameters of red blood cell concentrate (RCC) products.

Methods

RCCs were produced using whole blood filtration (WBF) or red cell filtration (RCF) (n = 12/method), refrigerated for 43 days, and evaluated for EV size profile and concentration, red cell deformability, ATP and 2,3-DPG, hemolysis, and hematological indices.

Results

The total number of EVs increased significantly with storage in both methods, and WBF-RCCs contained the higher numbers of EVs compared to RCF-RCCs. The concentration of small EVs was greater in WBF-RCCs versus RCF-RCCs, with difference between the two methods observed on day 43 of storage (p = 0.001). Throughout storage, significant decreases were identified in ATP, 2,3-DPG, and EI_max, while an increase in hemolysis was observed in both RCC products.

Conclusion

The dynamic shift in the size and concentration of the EV subpopulations is dependent on the blood manufacturing method and length of storage. Better understanding of the potential clinical implications of these heterogeneous populations of EVs are needed.

Plasma Transfusion: History, Current Realities, and Novel Improvements

Traumatic hemorrhage is the leading cause of preventable death after trauma. Early transfusion of plasma and balanced transfusion have been shown to optimize survival, mitigate the acute coagulopathy of trauma, and restore the endothelial glycocalyx. There are a myriad of plasma formulations available worldwide, including fresh frozen plasma, thawed plasma, liquid plasma, plasma frozen within 24 h, and lyophilized plasma (LP). Significant equipoise exists in the literature regarding the optimal plasma formulation. LP is a freeze-dried formulation that was originally developed in the 1930s and used by the American and British military in World War II. It was subsequently discontinued due to risk of disease transmission from pooled donors. Recently, there has been a significant amount of research focusing on optimizing reconstitution of LP. Findings show that sterile water buffered with ascorbic acid results in decreased blood loss with suppression of systemic inflammation. We are now beginning to realize the creation of a plasma-derived formulation that rapidly produces the associated benefits without logistical or safety constraints. This review will highlight the history of plasma, detail the various types of plasma formulations currently available, their pathophysiological effects, impacts of storage on coagulation factors in vitro and in vivo, novel concepts, and future directions.

Outcomes Related to the Use of Frozen Plasma or Pooled Solvent/Detergent-Treated Plasma in Critically Ill Children

OBJECTIVE

To determine if the use of fresh frozen plasma/frozen plasma 24 hours compared to solvent detergent plasma is associated with international normalized ratio reduction or ICU mortality in critically ill children.

DESIGN

This is an a priori secondary analysis of a prospective, observational study. Study groups were defined as those transfused with either fresh frozen plasma/frozen plasma 24 hours or solvent detergent plasma. Outcomes were international normalized ratio reduction and ICU mortality. Multivariable logistic regression was used to determine independent associations.

SETTING

One hundred one PICUs in 21 countries.

PATIENTS

All critically ill children admitted to a participating unit were included if they received at least one plasma unit during six predefined 1-week (Monday to Friday) periods. All children were exclusively transfused with either fresh frozen plasma/frozen plasma 24 hours or solvent detergent plasma.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were 443 patients enrolled in the study. Twenty-four patients (5%) were excluded because no plasma type was recorded; the remaining 419 patients were analyzed. Fresh frozen plasma/frozen plasma 24 hours group included 357 patients, and the solvent detergent plasma group included 62 patients. The median (interquartile range) age and weight were 1 year (0.2-6.4) and 9.4 kg (4.0-21.1), respectively. There was no difference in reason for admission, severity of illness score, pretransfusion international normalized ratio, or lactate values; however, there was a difference in primary indication for plasma transfusion (p < 0.001). There was no difference in median (interquartile range) international normalized ratio reduction, between fresh frozen plasma/frozen plasma 24 hours and solvent detergent plasma study groups, -0.2 (-0.4 to 0) and -0.2 (-0.3 to 0), respectively (p = 0.80). ICU mortality was lower in the solvent detergent plasma versus fresh frozen plasma/frozen plasma 24 hours groups, 14.5% versus 29.1%%, respectively (p = 0.02). Upon adjusted analysis, solvent detergent plasma transfusion was independently associated with reduced ICU mortality (odds ratio, 0.40; 95% CI, 0.16-0.99; p = 0.05).

CONCLUSIONS

Solvent detergent plasma use in critically ill children may be associated with improved survival. This hypothesis-generating data support a randomized controlled trial comparing solvent detergent plasma to fresh frozen plasma/frozen plasma 24 hours.

Transfusion-related immunomodulation: review of the literature and implications for pediatric critical illness

Transfusion-related immunomodulation (TRIM) in the intensive care unit (ICU) is difficult to define and likely represents a complicated set of physiologic responses to transfusion, including both proinflammatory and immunosuppressive effects. Similarly, the immunologic response to critical illness in both adults and children is highly complex and is characterized by both acute inflammation and acquired immune suppression. How transfusion may contribute to or perpetuate these phenotypes in the ICU is poorly understood, despite the fact that transfusion is common in critically ill patients. Both hyperinflammation and severe immune suppression are associated with poor outcomes from critical illness, underscoring the need to understand potential immunologic consequences of blood product transfusion. In this review we outline the dynamic immunologic response to critical illness, provide clinical evidence in support of immunomodulatory effects of blood product transfusion, review preclinical and translational studies to date of TRIM, and provide insight into future research directions.

Where now for transfusion: the evolution of a paradigm and its logical progression

The development of transfusion over the past century and a half has been described as one of the blessings of modern medicine. But, in some ways, it is emerging as a decidedly mixed blessing, bringing epidemics as well as improved health. Given all the practice has been through, now is the right time to take a critical look at blood transfusion as it is practiced today, and whether it serves the individual patient as effectively as the interests of those who administer it.