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BACKGROUND Hemorrhage is the leading cause of preventable trauma-related mortality and is frequently aggravated by acute traumatic coagulopathy (ATC). Viscoelastic tests such as rotational thromboelastometry (ROTEM) may improve identification and management of ATC. This study aimed to prospectively evaluate changes in ROTEM among combat casualties during the first 24 hours and compare the capabilities of our conventional clotting assay (international normalized ratio [INR], >1.2) to a proposed integrated ROTEM model (INR >1.2 with the addition of tissue factor pathway activation thromboelastometry [EXTEM] A5 ≤35 mm and/or EXTEM LI30

BACKGROUND Cold-stored platelets are an attractive option for treatment of actively bleeding patients due to a reduced risk of septic complications and preserved hemostatic function compared to conventional room temperature-stored platelets. However, refrigeration causes increased platelet activation and aggregate formation. Specialized pro-resolving mediators (SPMs), cell signaling mediators biosynthesized from essential fatty acids, have been shown to modulate platelet function and activation. In this study, we sought to determine if SPMs could be used to inhibit cold-stored platelet activation. METHODS Platelets were collected from healthy donors (n = 4-7) and treated with SPMs (resolvin E1 [RvE1], maresin 1 [MaR1], and resolvin D2 [RvD2]) or vehicle (VEH; 0.1% EtOH). Platelets were stored without agitation in the cold and assayed on Days 0 and 7 of storage for platelet activation levels using flow cytometry, platelet count, aggregation response using impedance aggregometry, and nucleotide content using mass spectrometry. RESULTS Compared to VEH, SPM treatment inhibited GPIb shedding (all compounds), significantly reduced both PS exposure and activation of GPIIb/IIIa receptor (RvD2, MaR1), and preserved aggregation response to TRAP (RvD2, MaR1) after 7 days of storage. Similar to untreated cold-stored platelets, SPM-treated samples did not preserve platelet counts or block the release of P-Selectin. Nucleotide content was unaffected by SPM treatment in cold-stored platelets. CONCLUSIONS SPM treatment, particularly Mar1 and RvD2, led to reduced platelet activation and preserved platelet function after 7 days of storage in the cold. Future work is warranted to better elucidate the mechanism of action of SPMs on cold platelet function and activation.

Background This study evaluated blood components processed by the platelet rich plasma (PRP) method from fresh whole blood (FWB) treated with a pathogen reduction technology (PRT). The effects of storage temperature on PRT treated platelet concentrates (PCs) were also examined. Study design and methods PRT was performed using riboflavin and ultraviolet light on FWB in citrate phosphate dextrose anticoagulant. Following PRT, red blood cells (RBCs), PCs, and plasma for fresh frozen plasma (FFP), were isolated by sequential centrifugation. RBCs were stored at 4°C, FFP at -80°C, and PC at 22°C or at 4°C. Components were assayed throughout their storage times for blood gases, chemistry and CBC, hemostatic function as well as platelet (PLT) and RBC integrity. Results Component processing following PRT resulted in a significant drop in platelet recovery. Most PRT-PC bags fell below AABB guidelines for platelet count. PRT-PC also showed a decrease in clot strength and decreased aggregometry response. Platelet caspases were activated by PRT. Storage at 4°C improved platelet function. In PRT-FFP, prothrombin time and partial thromboplastin time (PT and aPTT) were prolonged; factors V, VII, VIII, and XI, protein C, and fibrinogen were significantly decreased. Free hemoglobin was elevated two-fold in PRT-RBC. Conclusion Blood components isolated by the PRP method from PRT-treated WB result in a high percentage of PC that fail to meet AABB guidelines. FFP also shows diminished coagulation capacity. However, PRT-RBC are comparable to control-RBC. PRT-WB retains acceptable hemostatic function but alternatives to the PRP method of component separation may be more suitable.

Damage control resuscitation (DCR) for trauma, initially described to address the entire lethal triad (hypothermia, acidosis and coagulopathy) immediately upon admission to a combat hospital before damage control surgery (DCS), is now accepted as part of an integrated approach DCR-DCS from point of wounding to definitive treatment. Therefore, DCR can be divided in two steps: while bleeding is ongoing and once bleeding has been stopped.ATLS ABCDE protocol addresses main components of DCR (permissive hypotension, early plasma administration…). European guideline on management of major bleeding accepts transient use of vasopressors in case of life-threatening hypotension. Red blood cells not only carry and deliver oxygen to tissues but also play a major role in haemostasis; the Hb threshold for RBC transfusion is set to 7-9 g/dL. The fibrinolysis is an essential part of the acute coagulopathy of trauma and can be lowered by early tranexamic acid administration. The replacement of shed, consumed, diluted or inactivated coagulation factors and platelets is crucial to restore haemostasis. Lyophilized plasma or PCC are an alternative to fresh frozen plasma. Fibrinogen, a key component in the coagulation cascade can be administered through cryoprecipitate or fibrinogen concentrate. Viscoelastic techniques allow early diagnosis of coagulopathy and appropriate action.Once bleeding has been stopped, physiology is restored in intensive care unit. Sequelae of hypotension-related metabolic failure are reversed and coagulopathy is aggressively corrected as well as hypothermia. With the aim to restore adequate perfusion of organs, mean arterial blood pressure is targeted to 65 mmHg. The second look operation is scheduled when the lethal triad is under control. “Unplanned” reoperation can be decided because of ongoing surgical bleeding, missed visceral injury or development of an abdominal compartment syndrome.The treatment of bleeding remains to stop the bleeding. DCR is together with DCS part of a global DC strategy. DCR is a potent tool to hinder and even reverse the lethal triad. Delaying bleeding control under the pretext that DCR is available and effective is a fallacious conduct that results in increased morbidity and mortality.

Hemostatic resuscitation principles have significantly changed adult trauma resuscitation over the past decade. Practice patterns in pediatric resuscitation likely have changed as well; however, this evolution has not been quantified. We evaluated pediatric resuscitation practices over time within a combat trauma system.The Department of Defense Trauma Registry was queried from 2001 to 2013 for pediatric patients (18 years). Patients with burns, drowning, and missing injury severity score were excluded. Volumes of crystalloid, packed red blood cells (PRBC), whole blood, plasma, and platelets (PLT) given in the first 24 hours were calculated per kilogram body weight. Tranexamic acid use was also determined. Patients were divided into Early (2001-2005) and Late (2006-2013) cohorts, and subgroups of transfused (TX+) and massively transfused (MT+) patients were created. Intensive care unit and hospital length of stay and 24-hour and in-hospital mortality rates were compared.A total of 4,358 patients met inclusion criteria. Comparing Early versus Late, injuries from explosions, isolated or predominant head injuries, and injury severity score all increased. The proportion of TX+ patients also increased significantly (13.6% vs 37.4%, p0.001) as did the number of MT+ patients (2.1% vs 15.5%, p0.001). Transfusion of high plasma:RBC and PLT:RBC ratios increased in both the TX+ and MT+ subgroups, although overall, PLT and whole blood use was low. After adjusting for differences between groups, the odds of death was no different Early versus Late but decreased significantly in the MT+ patients with time as a continuous variable.Transfusion practice in pediatric combat casualty care shifted toward a more hemostatic approach over time. All-cause mortality was low and remained stable overall and even decreased in MT+ patients despite more injuries due to explosions, more head injuries, and greater injury severity. However, further study is required to determine the optimal resuscitation practices in critically injured children.Epidemiologic study, level IV.

Alterations in coagulation, inflammation and immunity are associated with major injury. As platelets have both coagulation and immune functions, the aim of this study is to correlate platelet activation with the immunoinflammatory response in trauma and burn patients. Blood samples were drawn from trauma and burn patients and healthy volunteers. Platelet (sCD40L) and coagulation (D-dimers) activation, cytokines and inflammatory markers were assessed. sCD40L, D-dimers and cytokines were elevated in both injury groups. Overall, sCD40L levels correlated with interleukin (IL)-6 and tumour necrosis factor-alpha. Subanalysis revealed a correlation between sCD40L and IL-17a in the healthy volunteers and burn groups, but not the trauma group. A parallel activation of platelets and the inflammatory response occurs postinjury. However, in trauma patients, a potential critical interrelationship between platelet activation and the Th-17 response appears to be lacking, which may contribute to coagulopathic and immunoinflammatory complications and warrants further study.

Deglycerolized red blood cells have been used by the U.S. military for half a century, starting with the Vietnam War. Deglycerolized red blood cells have a frozen storage life of 10 years, but require special equipment to thaw and deglycerolize. The available data show no difference in either efficacy with complications when compared to standard product red blood cells.

Cryopreserved and lyophilized platelets have a long, but limited, history of human use that dates back to the 1950s yet involves a small number of total study subjects (Fig. 9.1). Despite decades of research characterizing the quality and nature of these products, questions remain regarding the relationship between in vitro performance and in vivo function to control bleeding. That said, results to date indicate promising in vivo hemostatic potential in several animal models. Although the data is retrospective and cannot definitively establish causality, human use of cryopreserved platelets in military settings also appears to be associated with benefit. The regulatory pathway for these products, particularly in the case of cryopreserved platelets, has been decades long, and more trials are needed to provide high-quality data to regulatory bodies. These products could be life-saving in settings where other good alternatives are limited or unavailable.

BACKGROUND To provide whole blood on the battlefield can be a challenge, but a buddy system protocol is both an elegant and the only currently available means to supply blood to a Special Forces team in far-forward locations. Our aim was to investigate donor-safety associated with such a protocol. METHODS This study was a randomized, double-blinded, controlled trial that aimed to evaluate the immediate effects of a 450 cc blood donation on physical performance in fatigued and dehydrated Special Forces soldiers. The primary outcome variables were absolute and relative maximal oxygen uptake (VO2max), exercise tolerance time (ETT) and heart rate (HR). RESULTS Relative VO2max decreased by 7.1% in the donation group between pre and posttest, compared to no change in the control group. Absolute VO2max decreased by 11.2 and 3.6% between pre and posttest in the donation and control groups, respectively. Mean ETT in the donation group was on average 92 seconds shorter compared to baseline, which represents a decrease of 9.5%. CONCLUSION Donating blood after a week of strenuous physical activity is feasible for Special Forces personnel. While the donation results in some diminishment of VO2max, a 3.6%-11.2% decrease in relative VO2max, and in elevation of submaximal HR levels highly trained personnel continue to perform well both at both sub-maximal and maximal effort levels.

Recent combat experience reignited interest in transfusing whole blood (WB) for patients with life-threatening bleeding. US Army data indicate that WB transfusion is associated with improved or comparable survival compared to resuscitation with blood components. These data complement randomized controlled trials that indicate that platelet (PLT)-containing blood products stored at 4°C have superior hemostatic function, based on reduced bleeding and improved functional measures of hemostasis, compared to PLT-containing blood products at 22°C. WB is rarely available in civilian hospitals and as a result is rarely transfused for patients with hemorrhagic shock. Recent developments suggest that impediments to WB availability can be overcome, specifically the misconceptions that WB must be ABO specific, that WB cannot be leukoreduced and maintain PLTs, and finally that cold storage causes loss of PLT function. Data indicate that the use of low anti-A and anti-B titer group O WB is safe as a universal donor, WB can be leukoreduced with PLT-sparing filters, and WB stored at 4°C retains PLT function during 15 days of storage. The understanding that these perceived barriers are not insurmountable will improve the availability of WB and facilitate its use. In addition, there are logistic and economic advantages of WB-based resuscitation compared to component therapy for hemorrhagic shock. The use of low-titer group O WB stored for up to 15 days at 4°C merits further study to compare its efficacy and safety with current resuscitation approaches for all patients with life-threatening bleeding.

The early transfusion of plasma is important to ensure optimal survival of patients with traumatic hemorrhage. In military and remote or austere civilian settings, it may be impossible to move patients to hospital facilities within the first few hours of injury. A dried plasma product with reduced logistical requirements is needed to enable plasma transfusion where medically needed, instead of only where freezers and other equipment are available. First developed in the 1930s, pooled lyophilized plasma was widely used by British and American forces in WWII and the Korean War. Historical dried plasma products solved the logistical problem but were abandoned because of disease transmission. Modern methods to improve blood safety have made it possible to produce safe and effective dried plasma. Dried plasma products are available in France, Germany, South Africa, and a limited number of other countries. However, no product is available in the US. Promising products are in development that employ different methods of drying, pathogen reduction, pooling, packaging, and other approaches. Although challenges exist, the in vitro and in vivo data suggest that these products have great potential to be safe and effective. The history, state of the science, and recent developments in dried plasma are reviewed.

BACKGROUND Platelets (PLTs) are stored at room temperature (RT) to preserve in vivo circulation time, but PLT quality is degraded. The PLT storage lesion is mitigated by refrigeration, but questions remain regarding effects of cold storage (4°C) on mitochondrial function. Mitochondrial reactive oxygen species (ROS) generation may adversely affect PLT function and viability during storage, and refrigeration may mitigate these effects. STUDY DESIGN AND METHODS PLTs were stored under two temperature conditions (RT, 20-24°C; or 4°C, 1-6°C) and four storage durations (baseline [BL] and Days 3, 5, and 7). Mitochondrial respiration and maximal oxygen utilization were assessed with high-resolution respirometry. Mitochondrial ROS generation was assessed using a superoxide stain. Rotational thromboelastometry (ROTEM) was performed at BL and on Day 5 to assess PLT function. Collagen-induced PLT aggregation was measured by impedance aggregometry. RESULTS Mitochondrial ROS in 4°C-stored samples were lower compared to RT and retained a greater capacity to generate ROS after activation. Mitochondrial respiration and maximal mitochondrial utilization was conserved in PLTs stored at 4°C. ROTEM data demonstrated that net maximum clot firmness was higher in 4°C samples compared to RT and prevented fibrinolysis. The aggregation response to collagen was preserved in the 4°C samples versus RT-stored PLTs. Aggregation impairment correlated well with attenuated mitochondrial respiration and elevated production of intracellular mitochondrial ROS in the RT PLTs. CONCLUSION Mitochondrial damage and ROS production may contribute to loss of PLT viability during storage, whereas cold storage is known to preserve PLT function. Here we demonstrate that 4°C storage results in less oxidant stress and preserves mitochondrial function and potential compared to RT.

BACKGROUND Transfusion of plasma from recovered patients after Ebolavirus (EBOV) infection, typically called “convalescent plasma,” is an effective treatment for active disease available in endemic areas, but carries the risk of introducing other pathogens, including other strains of EBOV. A pathogen reduction technology using ultraviolet light and riboflavin (UV+RB) is effective against multiple enveloped, negative-sense, single-stranded RNA viruses that are similar in structure to EBOV. We hypothesized that UV+RB is effective against EBOV in blood products without activating complement or reducing protective immunoglobulin titers that are important for the treatment of Ebola virus disease (EVD). STUDY DESIGN AND METHODS Four in vitro experiments were conducted to evaluate effects of UV+RB on green fluorescent protein EBOV (EBOV-GFP), wild-type EBOV in serum, and whole blood, respectively, and on immunoglobulins and complement in plasma. Initial titers for Experiments 1 to 3 were 4.21 log GFP units/mL, 4.96 log infectious units/mL, and 4.23 log plaque-forming units/mL. Conditions tested in the first three experiments included the following: 1—EBOV-GFP plus UV+RB; 2—EBOV-GFP plus RB only; 3—EBOV-GFP plus UV only; 4—EBOV-GFP without RB or UV; 5—virus-free control plus UV only; and 6—virus-free control without RB or UV. RESULTS UV+RB reduced EBOV titers to nondetectable levels in both nonhuman primate serum (≥2.8- to 3.2-log reduction) and human whole blood (≥3.0-log reduction) without decreasing protective antibody titers in human plasma. CONCLUSION Our in vitro results demonstrate that the UV+RB treatment efficiently reduces EBOV titers to below limits of detection in both serum and whole blood. In vivo testing to determine whether UV+RB can improve convalescent blood product safety is indicated.

BACKGROUND Platelet (PLT) storage has been limited to 5 days at room temperature due to metabolic decline and risk for bacterial contamination. Refrigeration preserves PLT metabolism and function as well as limits bacterial growth; however, cold storage of PLTs also leads to aggregate formation. We hypothesized that storage of PLT concentrates at 4°C leads to glycoprotein (GP)IIb-IIIa activation and thus aggregate formation through fibrinogen binding and that this could be prevented by storing PLTs in PLT additive solution (PAS) without compromising PLT function. STUDY DESIGN AND METHODS Apheresis PLTs in plasma (AP) or apheresis PLTs in PAS were stored at 22 or 4°C for up to 15 days. Measurements include PLT counts, blood gases, aggregation response, flow cytometry analysis of integrin levels, activation markers, and microparticle formation. RESULTS Storage of AP 4°C led to a gradual decline in PLT count and an increase in aggregate formation that was mediated by intracellular calcium leak and fibrinogen receptor activation. Storage of PAS at 4°C prevented aggregate formation due to dilution of plasma fibrinogen. PAS stored at 4°C maintained aggregation responses to multiple agonists better than 22°C controls. CONCLUSION Storage of AP at 4°C leads to low level GPIIb-IIIa activation and results in aggregate formation over time. Separating the PLTs from the plasma component and storing them in PAS at 4°C resolves aggregate formation and preserves the metabolic and functional responses of these stored PLTs.

Refrigeration of platelets (4°C) provides the possibility of improving transfusion practice over the current standard-of-care, room temperature (RT) storage. However, the increased level of platelet activation observed at 4°C in vitro is cause for concern of uncontrolled thrombosis in vivo. In this study, we assessed the safety of 4°C-stored platelets by evaluating their response to physiologic inhibitors prostacyclin (PGI2) and nitric oxide (NO). Apheresis platelets were collected from healthy donors (n = 4) and tested on Day 1 (fresh) or Day 5 (RT- and 4°C-stored) after treatment with PGI2 and NO or not for: thrombin generation; factor V (FV) activity; intracellular free calcium, cAMP and cGMP; ATP release; TRAP-induced activation; aggregation to ADP, collagen, and TRAP, and adhesion to collagen under arterial flow. Data were analyzed using two-way ANOVA and post-hoc Tukey test for multiple comparisons, with significance set at P

BackgroundTo study central hypovolemia in humans, lower body negative pressure (LBNP) is a recognized alternative to blood removal (HEM). While LBNP mimics the cardiovascular responses of HEM in baboons, similarities in hemostatic responses to LBNP and HEM remain unknown in this species.MethodsThirteen anesthetized baboons were exposed to progressive hypovolemia by HEM and, four weeks later, by LBNP. Hemostatic activity was evaluated by plasma markers, thromboelastography (TEG), flow cytometry, and platelet aggregometry at baseline (BL), during and after hypovolemia.ResultsBL values were indistinguishable for most parameters although platelet count, maximal clot strength (MA), protein C, thrombin anti-thrombin complex (TAT), thrombin activatable fibrinolysis inhibitor (TAFI) activity significantly differed between HEM and LBNP. Central hypovolemia induced by either method activated coagulation; TEG R-time decreased and MA increased during and after hypovolemia compared to BL. Platelets displayed activation by flow cytometry; platelet count and functional aggregometry were unchanged. TAFI activity and protein, Factors V and VIII, vWF, Proteins C and S all demonstrated hemodilution during HEM and hemoconcentration during LBNP, whereas tissue plasminogen activator (tPA), plasmin/anti-plasmin complex, and plasminogen activator inhibitor-1 did not. Fibrinolysis (TEG LY30) was unchanged by either method; however, at BL, fibrinolysis varied greatly. Post-hoc analysis separated baboons into low-lysis (LY30 2%) whose fibrinolytic state matched at both HEM and LBNP BL. In high-lysis, BL tPA and LY30 correlated strongly (r = 0.95; PConclusionsCentral hypovolemia induced by either LBNP or HEM resulted in activation of coagulation; thus, LBNP is an adjunct to study hemorrhage-induced pro-coagulation in baboons. Furthermore, this study revealed a subset of baboons with baseline hyperfibrinolysis, which was strongly coupled to tPA and uncoupled from TAFI activity.

BACKGROUNDSevere Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has recently been identified as the causative agent for Coronavirus Disease 2019 (COVID-19). The ability of this agent to be transmitted by blood transfusion has not been documented, although viral RNA has been detected in serum. Exposure to treatment with riboflavin and ultraviolet light (R + UV) reduces blood-borne pathogens while maintaining blood product quality. Here, we report on the efficacy of R + UV in reducing SARS-CoV-2 infectivity when tested in human plasma and whole blood products.STUDY DESIGN AND METHODSSARS-CoV-2 (isolate USA-WA1/2020) was used to inoculate plasma and whole blood units that then underwent treatment with riboflavin and UV light (Mirasol Pathogen Reduction Technology System, Terumo BCT, Lakewood, CO). The infectious titers of SARS-CoV-2 in the samples before and after R + UV treatment were determined by plaque assay on Vero cells. Each plasma pool (n=9) underwent R + UV treatment performed in triplicate using individual units of plasma and then repeated using individual whole blood donations (n=3).RESULTSRiboflavin and UV light reduced the infectious titer of SARS-CoV-2 below the limit of detection for plasma products at 60-100% of the recommended energy dose. At the UV light dose recommended by the manufacturer, the mean log reductions in the viral titers were ≥ 4.79 ± 0.15 Logs in plasma and 3.30 ± 0.26 in whole blood units.CONCLUSIONRiboflavin and UV light effectively reduced the titer of SARS-CoV-2 to the limit of detection in human plasma and by 3.30 ± 0.26 on average in whole blood. Two clades of SARS-CoV-2 have been described and questions remain about whether exposure to one strain confers strong immunity to the other. Pathogen-reduced blood products may be a safer option for critically ill patients with COVID-19, particularly those in high-risk categories.

Background Using platelet additive solution (PAS) to dilute fibrinogen during long-term cold storage of platelets (PLTs) decreases PLT activation and increases functional PLT shelf life. We performed a randomized, paired study to assess the in vitro quality of PLTs stored in the cold in T-PAS+ for up to 18 days evaluated against PLTs stored under currently allowable conditions (5-day room temperature-stored PLTs [RTP] and 3-day cold-stored PLTs [CSP]). Study design and methods PLTs were collected from healthy volunteers (n = 10) and diluted to 65% T-PAS+/35% plasma before cold storage. Double-dose apheresis PLTs (in 100% plasma) were collected from the same donors and split into two bags (one bag RTP, one bag CSP). All bags were sampled on the day of collection (Day 0). CSP and RTP bags were sampled on Days 3 and 5, respectively. T-PAS+ samples were assessed on Days 3, 5, 14, 16, and 18 of storage for metabolism, hemostatic function, and activation. Results After 18 days of storage in T-PAS+, pH was 6.71 ± 0.04, PLT count was comparable to Day 3 CSP, PLT function (aggregation and clot strength) was comparable to Day 5 RTP, and PLT activation was significantly increased. Conclusion Refrigerated PLTs stored in T-PAS+ for 18 days met FDA pH standards. Functional metrics suggest activity of T-PAS+-stored PLTs and the potential to contribute to hemostasis throughout 18 days of storage. Extending the shelf life of PLTs would increase access to hemostatic resuscitation for bleeding patients in military and civilian settings.

Background Formulation of a medical preparedness plan for treating severely bleeding casualties during naval deployment is a significant challenge because of territory covered during most missions. The aim of this study was to evaluate the concept of "walking blood bank" as a supportable plan for supplying safe blood and blood products. Methods In 2013, the Royal Norwegian Navy conducted antipiracy operations from a frigate, beginning in the Gulf of Aden and ending in the Indian Ocean. Crews were on 24-hour emergency alert in preparation for an enemy assault on the frigate. Under an approved command protocol, a "walking blood bank," using crew blood donations, was established for use on board and on missions conducted in rigid-hulled inflatable boats, during which freeze-dried plasma and leukoreduced, group O low anti-A/anti-B titer, cold-stored whole blood were stored in Golden Hour Boxes. Data demonstrating the ability to collect, store, and provide whole blood were collected to establish feasibility of implementing a whole blood-focused remote damage-control resuscitation program aboard a naval vessel. In addition, ROTEM data were collected to demonstrate feasibility of performing this analysis on a large naval vessel and to also measure hemostatic efficacy of cold-stored leukoreduced whole blood (CWB) stored during a period of 14 days. ROTEM data on CWB was compared with reconstituted whole blood. Results Drills simulating massive transfusion activation were conducted, in which 2 U of warm fresh whole blood with platelet sparing leukoreduction were produced in 40 minutes, followed by collection of two additional units at 15-minute increments. The ROTEM machine performed well during ship-rolling, as shown by the overlapping calculated and measured mechanical piston movements measured by the ROTEM device. Error messages were recorded in 4 (1.5%) of 267 tests. CWB yielded reproducible ROTEM results demonstrating preserved fibrinogen function and platelet function for at least 3.5 weeks and 2 weeks, respectively. The frequency of ROTEM tests were as follows: EXTEM (n = 88), INTEM (n = 85), FIBTEM (n = 82), and APTEM (n = 12). CWB results were grouped. Compared with Days 0 to 2, EXTEM maximum clot firmness was significantly reduced, beginning on Days 10 to 14; however, results through that date remained within reference ranges and were comparable with the EXTEM maximum clot firmness for the reconstituted whole blood samples containing Day 5 room temperature-stored platelets. Conclusion A "walking blood bank" can provide a balanced transfusion product to support damage-control resuscitation/remote damage-control resuscitation aboard a frigate in the absence of conventional blood bank products. ROTEM analysis is feasible to monitor damage-control resuscitation and blood product quality. ROTEM analysis was possible in challenging operational conditions. Level of evidence Therapeutic study, level V.

The aim of this study was to determine whether visceral protein levels increase under positive nitrogen balance during times of decrease in acute-phase reactant levels in patients with burn injury. This was a post hoc analysis of a prospective, interventional study approved by the local institutional review board. A total of 10 subjects between the ages of 18 and 72 with ≥ 20% total body surface area burn were enrolled over a 14-month period. Data were collected for five subjects (average age of 28 ± 8 years and total body surface area burn of 69 ± 15%) who met the inclusion criteria. Changes in visceral protein levels were examined along with nitrogen balance and acute-phase reactants when the subjects were on enteral nutrition, and the proteins were not examined during times of acute kidney injury. Descriptive statistics were performed, and linear regression was used to analyze the association of visceral proteins and nitrogen balance during times that acute-phase reactant levels were decreasing. The subjects received an average of 3044 ± 1613 kcal/day (39 ± 20 kcal/kg), meeting 72% of caloric goals and achieving positive nitrogen balance during 68% of the 40 weekly measurements, with 174 ± 85 g of protein intake per day (2.2 ± 1.1 g/kg). There was a weak relationship between nitrogen balance and changes in visceral protein levels during times that the acute-phase reactant levels were decreasing (P > .05). Visceral proteins were found to be poor markers of nutritional status. This study is unique because the subjects were able to achieve positive nitrogen balance despite severe burns.

Currently, platelets (PLTs) stored at room temperature (RT) for 5-7 days with gentle agitation are exclusively used for transfusion although FDA recently clarified that apheresis PLTs stored at 4°C for up to 72 hours may be used for treating active hemorrhage. We have demonstrated that cold (4C) storage of PLT is an attractive alternative to RT storage since it better preserves the PLT metabolic reserves, in vitro responses to agonists of activation, aggregation and physiologic inhibitors, as well as adhesion to thrombogenic surfaces. In this study, we tested the hypothesis that 4C-stored PLT will form clots with mechanical strength superior to those from RT-stored PLT due to higher hemostatic potential. From rheological measurements, we observed that the clots formed from 5 day 4C-stored PLTs are significantly stiffer (elastic modulus) and stronger (critical stress) than those formed from RT-stored PLT but comparable to fresh PLT (Fig. A). We also observed from ultrastructural microscopy that the fibrin fibers in clots from cold-stored PLT were thinner with more branch points than those from RT-stored PLTs, indicating the presence of increased crosslinks (Fig. B, C). Finally, molecular analysis revealed an increase FXIII transglutaminase activity due to the binding of plasma FXIII/fibrinogen to the surface of 4C-stored PLTs (Fig D).In conclusion, we have shown that cold-induced plasma FXIII binding to PLT surface result in increased fibrin crosslinking and enhanced clot strength. Our data, together with the benefit of reduced risk of late thrombosis due to their rapid clearance in vivo , underscores the consideration of 4C-stored PLT for acute response to hemorrhage. Figure 1 (A) RT-stored platelets form clots with less stiffness (n=5); (B) Representative SEM images of clots (n=3) (C) Clots from 4C-stored platelets have higher cross-linking density (n=5) (D) In FXIII-deficient plasma, 4C-stored platelets form clots with higher stiffness than fresh platelets (n=4)

Insulin controls hyperglycemia after severe burns, and its use opposes the hypermetabolic response. The underlying molecular mechanisms are poorly understood, and previous research in this area has been limited because of the inadequacy of animal models to mimic the physiological effects seen in humans with burns. Using a recently published rat model that combines both burn and disuse components, we compare the effects of insulin treatment vs. vehicle on glucose tolerance, hypermetabolic response, muscle loss, and circadian-metabolic protein expression after burns. Male Sprague-Dawley rats were assigned to three groups: cage controls ( n = 6); vehicle-treated burn and hindlimb unloading (VBH; n = 11), and insulin-treated burn and hindlimb unloading (IBH; n = 9). With the exception of cage controls, rats underwent a 40% total body surface area burn with hindlimb unloading, then IBH rats received 12 days of subcutaneous insulin injections (5 units·kg−1·day−1), and VBH rats received an equivalent dose of vehicle. Glucose tolerance testing was performed on day 14, after which blood and tissues were collected for analysis. Body mass loss was attenuated by insulin treatment (VBH = 265 ± 17 g vs. IBH = 283 ± 14 g, P = 0.016), and glucose clearance capacity was increased. Soleus and gastrocnemius muscle loss was decreased in the IBH group. Insulin receptor substrate-1, AKT, FOXO-1, caspase-3, and PER1 phosphorylation was altered by injury and disuse, with levels restored by insulin treatment in almost all cases. Insulin treatment after burn and during disuse attenuated the hypermetabolic response, increased glucose clearance, and normalized circadian-metabolic protein expression patterns. Therapies aimed at targeting downstream effectors may provide the beneficial effects of insulin without hypoglycemic risk.

Background: Lower body negative pressure (LBNP) has been established in human studies as an alternative method to blood removal (HEM) to study central hypovolemia. In a baboon model, LBNP also mimics the cardiovascular response of HEM. Hemostatic responses, including platelet activation, coagulation and fibrinolysis in response to LBNP and HEM in this baboon model are reported here. A previous meeting report from this study focused on hemostatic interactions; this report expands the assay of fibrinolytic proteins and includes detailed post-hoc analysis of interactions. Methods: Thirteen anesthetized baboons were exposed to progressive central hypovolemia by HEM and, four weeks later, by LBNP. Whole blood cell counts were determined; pro-coagulant and fibrinolytic activity was evaluated by plasma markers, thrombelastography, flow cytometry and platelet aggregometry at baseline (BL), intermediate hypovolemia (MID), presyncope or maximal hypovolemia (MAX) and after recovery (REC). Results: Baseline values for HEM (day 0) and LBNP (day 28) were indistinguishable for most analyzed parameters; however platelet number, maximal clotting (MA), Protein C, TAT, TAFI-activity, plasma renin, angiotensin and epinephrine were all significantly different (p2) whose fibrinolytic state matched at both HEM and LBNP BL. High lysis samples (n=8) showed a strong correlation (r=0.95; p Conclusions: Central hypovolemia resulted in activation of coagulation by either LBNP or HEM; thus LBNP is a powerful model for studying hemorrhage. This study also revealed a subset of baboons with baseline activation of fibrinolysis which was strongly coupled to tPA and uncoupled from TAFI activity. The methods demonstrated hemodilution with blood removal and hemoconcentration with LBNP, as has been observed in humans, but these modest changes had no significant effect on coagulation parameters. Unexpectedly, this study demonstrated that the effects of blood removal were sustained 28 days later on baseline parameters. Overall, these results in large primates suggest that baseline differences between apparently healthy and superficially homogeneous individuals may determine outcomes in studies of hemostasis. Disclosures No relevant conflicts of interest to declare.

Military conflicts create a dynamic medical environment in which the number of severe trauma cases is compressed in both time and space. In consequence, lessons are learned at a rapid pace. Because the military has an effective organizational structure at its disposal and the logistical capacity to rapidly disseminate new ideas, adoption of novel therapies and protective equipment occurs quickly. The recent conflicts in Iraq and Afghanistan are no exception: more than three dozen new clinical practice guidelines were implemented by the US Armed Forces, with attendant survival benefits, in response to observation and research by military physicians. Here we review the lessons learned by coalition medical personnel regarding resuscitation of severe trauma, integrating knowledge gained from massive transfusion, autopsies, and extensive review of medical records contained in the Joint Theater Trauma Registry. Changes in clinical care included the shift to resuscitation with 1:1:1 component therapy, use of fresh whole blood, and the application of both medical devices and pharmaceutical adjuncts to reduce bleeding. Future research will focus on emerging concepts regarding coagulopathy of trauma and evaluation of promising new blood products for far-forward resuscitation. New strategies aimed at reducing mortality on the battlefield will focus on resuscitation in the pre-hospital setting where hemorrhagic death continues to be a major challenge.

Summary Currently, platelets for transfusion are stored at room temperature (RT) for 5–7 days with gentle agitation, but this is less than optimal because of loss of function and risk of bacterial contamination. We have previously demonstrated that cold (4°C) storage is an attractive alternative because it preserves platelet metabolic reserves, in vitro responses to agonists of activation, aggregation and physiological inhibitors, as well as adhesion to thrombogenic surfaces better than RT storage. Recently, the US Food and Drug Administration clarified that apheresis platelets stored at 4°C for up to 72 h may be used for treating active haemorrhage. In this work, we tested the hypothesis that cold-stored platelets contribute to generating clots with superior mechanical properties compared to RT-stored platelets. Rheological studies demonstrate that the clots formed from platelets stored at 4°C for 5 days are significantly stiffer (higher elastic modulus) and stronger (higher critical stress) than those formed from RT-stored platelets. Morphological analysis shows that clot fibres from cold-stored platelets were denser, thinner, straighter and with more branch points or crosslinks than those from RT-stored platelets. Our results also show that the enhanced clot strength and packed structure is due to cold-induced plasma factor XIII binding to platelet surfaces, and the consequent increase in crosslinking.

Hypermetabolism is universal in the severely burned and is characterized by catabolism of lean mass and body fat with associated insulin resistance. Adipokines are likely to play a role in these changes but have not been identified to date in burn patients.From a single burn ICU, 17 burn patients with an expected stay14 days were studied. Study period began within 14 days of admission. Over 7 days, plasma samples were collected for measurement of leptin, adiponectin, resistin, ghrelin, insulin, and cortisol by ELISA. For comparison, samples from 15 healthy controls of similar age, BMI, and blood glucose were obtained.Mean age was 33±17 years and BMI 26±3.4. Average burn size was 45±20% TBSA and ISS 32±10 with 72% having inhalation injury; in-hospital mortality was 29%. Estimated energy needs were 3626±710 kcal, of which 84±21% were met by enteral feeding with intensive insulin treatment (glucose 80-110 mg/ml). Using the homeostasis model assessment of insulin resistance, burned subjects were more resistant than controls (17±11.3 and 8±10.0). Insulin levels were elevated (57±35.6 μU/ml in burned subject vs. 26±31.1 μU/ml in controls), and cortisol concentrations increased (50±41.2 μg/dl vs. 12±3.9 μg/dl). These traditional hormone changes were associated with increased resistin (16.6±5.5 ng/ml vs. 3.8±0.9 ng/ml) and decreased leptin (8.8±8.9 ng/ml vs. 19.4±23.5 ng/ml), adiponectin (9±3.5 ng/ml vs. 17±10.2 ng/ml), and ghrelin (0.37±0.14 ng/ml vs.0.56±0.26 ng/ml).Patients with burns, who are characteristically hypermetabolic with hypercortisolism and insulin resistant, have significant changes in adipokine levels that appear independent of the magnitude of initial injury or metabolic derangement. In addition, suppression of ghrelin in the presence of decreased leptin and adiponectin levels in combination with increased insulin and resistin levels represent unexpected changes in the metabolic milieu of the injured patient possibly due to dramatic activation of inflammatory pathways, indicating strategies for treatment.

BACKGROUND: Whole blood (WB) has been used in combat since World War I as it is readily available and replaces every element of shed blood. Component therapy has become standard; however, recent military successes with WB resuscitation have revived the debate regarding wider WB use. Characterization of optimal WB storage is needed. We hypothesized that refrigeration preserves WB function and that a pathogen reduction technology (PRT) based on riboflavin and ultraviolet light has no deleterious effect over 21 days of storage. STUDY DESIGN AND METHODS: WB units were stored for 21 days either at 4 C or 22 C. Half of each temperature group underwent PRT, yielding four final treatment groups (n = 8 each): CON 4 (WB at 4 C); CON 22 (WB at 22 C); PRT 4 (PRT WB at 4 C); and PRT 22 (PRT WB at 22 C). Testing was at baseline, Days 1-7, 10, 14, and 21. Assays included coagulation factors; platelet activation, aggregation, and adhesion; and thromboelastography (TEG). RESULTS: Prothrombin time (PT) and partial thromboplastin time increased over time; refrigeration attenuated the effects on PT (p /= 0.009). Aggregation decreased over time (p /= 0.001); losses were attenuated by refrigeration (p /= 0.001). Refrigeration preserved TEG parameters (p /= 0.001) and PRT 4 samples remained within normal limits throughout the study. Refrigeration in combination with PRT inhibited fibrinolysis (p /= 0.001) and microparticle formation (p /= 0.031). Cold storage increased shear-induced platelet aggregation and ristocetin-induced platelet agglutination (p /= 0.032), as well as GPIb-expressing platelets (p /= 0.009). CONCLUSION: The in vitro hemostatic function of WB is largely unaffected by PRT treatment and better preserved by cold storage over 21 days. Refrigerated PRT WB may be suitable for trauma resuscitation. Clinical studies are warranted.

Platelets (PLTs) are stored at room temperature (RT) to preserve in vivo circulation time, but PLT quality is degraded. The PLT storage lesion is mitigated by refrigeration, but questions remain regarding effects of cold storage (4°C) on mitochondrial function. Mitochondrial reactive oxygen species (ROS) generation may adversely affect PLT function and viability during storage, and refrigeration may mitigate these effects.PLTs were stored under two temperature conditions (RT, 20-24°C; or 4°C, 1-6°C) and four storage durations (baseline [BL] and Days 3, 5, and 7). Mitochondrial respiration and maximal oxygen utilization were assessed with high-resolution respirometry. Mitochondrial ROS generation was assessed using a superoxide stain. Rotational thromboelastometry (ROTEM) was performed at BL and on Day 5 to assess PLT function. Collagen-induced PLT aggregation was measured by impedance aggregometry.Mitochondrial ROS in 4°C-stored samples were lower compared to RT and retained a greater capacity to generate ROS after activation. Mitochondrial respiration and maximal mitochondrial utilization was conserved in PLTs stored at 4°C. ROTEM data demonstrated that net maximum clot firmness was higher in 4°C samples compared to RT and prevented fibrinolysis. The aggregation response to collagen was preserved in the 4°C samples versus RT-stored PLTs. Aggregation impairment correlated well with attenuated mitochondrial respiration and elevated production of intracellular mitochondrial ROS in the RT PLTs.Mitochondrial damage and ROS production may contribute to loss of PLT viability during storage, whereas cold storage is known to preserve PLT function. Here we demonstrate that 4°C storage results in less oxidant stress and preserves mitochondrial function and potential compared to RT.

PURPOSE The autotransfusion of unwashed (or unprocessed) shed hemothorax blood (USHB) in trauma patients is widely assumed to be beneficial; however, the inflammatory potential of shed pleural blood has not been thoroughly studied. Since previous studies have documented marked changes in coagulation function of shed pleural blood, we hypothesized that its level of inflammatory cytokines would be elevated. METHODS A prospective observational study of trauma patients in whom cytokine levels from USHB were compared to venous samples from healthy volunteers was conducted. Differences between the cytokine content of patient-derived samples were compared to those from healthy subjects. RESULTS There was a statistically significant increase in pro-inflammatory cytokines (IL-6, IL-8, TNFα, GM-CSF), a pro-inflammatory Th-1 cytokine (IFNγ), and anti-inflammatory Th-2 cytokines (IL-4 and IL-10) in shed pleural blood over four hours when compared with samples from healthy controls (P

The Joint Theater Trauma Registry database, begun early in Operation Iraqi Freedom and Operation Enduring Freedom, created a comprehensive repository of information that facilitated research efforts and produced rapid changes in clinical care. New clinical practice guidelines were adopted throughout the last decade. The damage-control resuscitation clinical practice guideline sought to provide high-quality blood products in support of tissue perfusion and hemostasis. The goal was to reduce death from hemorrhagic shock in patients with severe traumatic bleeding. This 10-year review of the Joint Theater Trauma Registry database reports the military's experience with resuscitation and coagulopathy, evaluates the effect of increased plasma and platelet (PLT)-to-red blood cell ratios, and analyzes other recent changes in practice.Records of US active duty service members at least 18 years of age who were admitted to a military hospital from March 2003 to February 2012 were entered into a database. Those who received at least one blood product (n = 3,632) were included in the analysis. Data were analyzed with respect to interactions within and between categories (demographics, admission characteristics, hospital course, and outcome). Transfusions were analyzed with respect to time, survival, and effect of increasing transfusion ratios.Coagulopathy was prevalent upon presentation (33% with international normalized ratio ≥ 1.5), correlated with increased mortality (fivefold higher), and was associated with the need for massive transfusion. High transfusion ratios of fresh frozen plasma and PLT to red blood cells were correlated with higher survival but not decreased blood requirement. Survival was most correlated with PLT ratio, but high fresh frozen plasma ratio had an additive effect (PLT odds ratio, 0.22).This 10-year evaluation supports earlier studies reporting the benefits of damage-control resuscitation strategies in military casualties requiring massive transfusion. The current analysis suggests that defects in PLT function may contribute to coagulopathy of trauma.Epidemiologic study, level IV.

This review is a synopsis of the decisions that shaped global policy on platelet (PLT) storage temperature and a focused appraisal of the literature on which those discussions were based. We hypothesize that choices were centered on optimization of preventive PLT transfusion strategies, possibly to the detriment of the therapeutic needs of acutely bleeding patients. Refrigerated PLTs are a better hemostatic product, and they are safer in that they are less prone to bacterial contamination. They were abandoned during the 1970s because of the belief that clinically effective PLTs should both be hemostatically functional and survive in circulation for several days as indicated for prophylactic transfusion; however, clinical practice may be changing. Data from two randomized controlled trials bring into question the concept that stable autologous stem cell transplant patients with hypoproliferative thrombocytopenia should continue to receive prophylactic transfusions. At the same time, new findings regarding the efficacy of cold PLTs and their potential role in treating acute bleeding have revived the debate regarding optimal PLT storage temperature. In summary, a "one-size-fits-all" strategy for PLT storage may not be adequate, and a reexamination of whether cold-stored PLTs should be offered as a widely available therapeutic product may be indicated.

Glycemic control with intensive insulin therapy (IIT) has received widespread adoption secondary to findings of improved clinical outcomes and survival in the burn population. Severe burn as a model for trauma is characterized by a hypermetabolic state, hyperglycemia, and insulin resistance. In this article, we review the findings of a burn center research facility in terms of understanding glucose management. The conferred benefits from IIT, our findings of poor outcomes associated with glycemic variability, advantages from preserved diurnal variation of glucose and insulin, and impacts of glucometer error and hematocrit correction factor are discussed. We conclude with direction for further study and the need for a reliable continuous glucose monitoring system. Such efforts will further the endeavor for achieving adequate glycemic control in order to assess the efficacy of target ranges and use of IIT.

The prevalence of intensive insulin and restrictive blood use protocols in burn centers is unknown, which may be problematic as the combined impact of these therapies is to concomitantly increase the prevalence of anemia and hypoglycemia in intensive care unit patients. Such a development is important because point-of-care (POC) glucometers report erroneously high values in the presence of low hematocrit (HCT), potentially masking the presence of hypoglycemia. We hypothesized that most American Burn Association (ABA) verified burn centers have adopted intensive insulin therapy while simultaneously restricting blood transfusions potentially increasing risk of hypoglycemia. All ABA verified burn centers (N = 44) were contacted. Clinical practices regarding intensive insulin therapy, restrictive transfusion practices, and the use of POC glucometers were evaluated. Intensive insulin protocols were implemented at 73% of ABA centers (defined as upper glucose target of < or = 120 mg/dl) and POC glucometers measurement was nearly universal; 95% of ABA centers use them routinely. Anemia is prevalent in intensive care units and may be increasing because of recent changes in practice. Defined hemoglobin and HCT levels trigger blood transfusion at 84% of centers, and of these, 51% restrict transfusion to hemoglobin < 7 g/dl or HCT < 22%. Most ABA centers now use intensive insulin protocols, many in combination with restrictive transfusion strategies. The combination of a higher prevalence of hypoglycemia in the presence of near universal anemia is concerning, particularly given the pervasiveness of glucometer use among burn centers.

Background: A point-of-care (POC) glucometer (G1) used for critical care at our institution is inaccurate in the presence of low hematocrit (HCT) values. The purpose of this study was to analyze error rates of three additional POC glucometer brands and determine mathematical correction formulas for each. Methods: Blood samples (n = 196) from a cohort of surgical, trauma, medical, cardiothoracic, and burn intensive care unit patients were tested on three commonly used POC glucometer brands (G2-G4). Results were compared with reference laboratory values, and correction compared with the validated formula for G1. A mathematical formula specific to each glucometer type was derived from glucose measurements, associated HCT values, and the degree of difference relative to laboratory results. Results: POC glucometer results were consistently elevated compared with reference laboratory values. Glucometer error rates for HCT ≤ 25% ranged from 15.4% to 22.3% for the three types. Error rates for 25% < HCT < 34% ranged from 16.4% to 18.4%. A correction formula for each glucometer based on the natural log transformation of the HCT predicted reference values with a mean error rate of -0.54% ± 5.6% for G2, -0.6% ± 5.5% for G3, and 0.2% ± 8.0% for G4. Correction was similar to that previously established for G1 (-0.01% ± 4.8). Conclusions: Significant error rates because of HCT effect were found in all glucometer models tested with accurate prediction of reference values with a simple mathematical formula.

The perioperative resuscitation approach to hemorrhagic shock is changing due to recent military experience in managing traumatic injury. For the past few decades, resuscitation of perioperative hemorrhagic shock has most commonly consisted of crystalloids and colloids, followed by RBCs, after which, if indicated according to laboratory results, plasma and platelets. If used, empiric ratios of RBC to plasma units ranged between 10 and 4 units of RBCs to 1 unit of plasma, without platelets. This approach was the foundation of Advanced Trauma Life Support (ATLS).

Severe burns lead to insulin resistance, which is associated with hyperglycemia and muscle wasting. Investigators showed relatively recently that control of hyperglycemia with intensive insulin treatment is associated with improved outcomes for those in the intensive care unit, including patients with severe burns. In this article, we review the actions of insulin in terms of glycemic control and muscle metabolism, biochemical and clinical effects of insulin treatment in the severely burned, and the vagaries of glucose control.

To provide whole blood on the battlefield can be a challenge, but a buddy system protocol is both an elegant and the only currently available means to supply blood to a Special Forces team in far-forward locations. Our aim was to investigate donor-safety associated with such a protocol.This study was a randomized, double-blinded, controlled trial that aimed to evaluate the immediate effects of a 450 cc blood donation on physical performance in fatigued and dehydrated Special Forces soldiers. The primary outcome variables were absolute and relative maximal oxygen uptake (VO2max ), exercise tolerance time (ETT) and heart rate (HR).Relative VO2max decreased by 7.1% in the donation group between pre and posttest, compared to no change in the control group. Absolute VO2max decreased by 11.2 and 3.6% between pre and posttest in the donation and control groups, respectively. Mean ETT in the donation group was on average 92 seconds shorter compared to baseline, which represents a decrease of 9.5%.Donating blood after a week of strenuous physical activity is feasible for Special Forces personnel. While the donation results in some diminishment of VO2max , a 3.6%-11.2% decrease in relative VO2max , and in elevation of submaximal HR levels highly trained personnel continue to perform well both at both sub-maximal and maximal effort levels.

Recent combat experience reignited interest in transfusing whole blood (WB) for patients with life-threatening bleeding. US Army data indicate that WB transfusion is associated with improved or comparable survival compared to resuscitation with blood components. These data complement randomized controlled trials that indicate that platelet (PLT)-containing blood products stored at 4°C have superior hemostatic function, based on reduced bleeding and improved functional measures of hemostasis, compared to PLT-containing blood products at 22°C. WB is rarely available in civilian hospitals and as a result is rarely transfused for patients with hemorrhagic shock. Recent developments suggest that impediments to WB availability can be overcome, specifically the misconceptions that WB must be ABO specific, that WB cannot be leukoreduced and maintain PLTs, and finally that cold storage causes loss of PLT function. Data indicate that the use of low anti-A and anti-B titer group O WB is safe as a universal donor, WB can be leukoreduced with PLT-sparing filters, and WB stored at 4°C retains PLT function during 15 days of storage. The understanding that these perceived barriers are not insurmountable will improve the availability of WB and facilitate its use. In addition, there are logistic and economic advantages of WB-based resuscitation compared to component therapy for hemorrhagic shock. The use of low-titer group O WB stored for up to 15 days at 4°C merits further study to compare its efficacy and safety with current resuscitation approaches for all patients with life-threatening bleeding.

The early transfusion of plasma is important to ensure optimal survival of patients with traumatic hemorrhage. In military and remote or austere civilian settings, it may be impossible to move patients to hospital facilities within the first few hours of injury. A dried plasma product with reduced logistical requirements is needed to enable plasma transfusion where medically needed, instead of only where freezers and other equipment are available. First developed in the 1930s, pooled lyophilized plasma was widely used by British and American forces in WWII and the Korean War. Historical dried plasma products solved the logistical problem but were abandoned because of disease transmission. Modern methods to improve blood safety have made it possible to produce safe and effective dried plasma. Dried plasma products are available in France, Germany, South Africa, and a limited number of other countries. However, no product is available in the US. Promising products are in development that employ different methods of drying, pathogen reduction, pooling, packaging, and other approaches. Although challenges exist, the in vitro and in vivo data suggest that these products have great potential to be safe and effective. The history, state of the science, and recent developments in dried plasma are reviewed.

Platelet (PLT) storage has been limited to 5 days at room temperature due to metabolic decline and risk for bacterial contamination. Refrigeration preserves PLT metabolism and function as well as limits bacterial growth; however, cold storage of PLTs also leads to aggregate formation. We hypothesized that storage of PLT concentrates at 4°C leads to glycoprotein (GP)IIb-IIIa activation and thus aggregate formation through fibrinogen binding and that this could be prevented by storing PLTs in PLT additive solution (PAS) without compromising PLT function.Apheresis PLTs in plasma (AP) or apheresis PLTs in PAS were stored at 22 or 4°C for up to 15 days. Measurements include PLT counts, blood gases, aggregation response, flow cytometry analysis of integrin levels, activation markers, and microparticle formation.Storage of AP 4°C led to a gradual decline in PLT count and an increase in aggregate formation that was mediated by intracellular calcium leak and fibrinogen receptor activation. Storage of PAS at 4°C prevented aggregate formation due to dilution of plasma fibrinogen. PAS stored at 4°C maintained aggregation responses to multiple agonists better than 22°C controls.Storage of AP at 4°C leads to low level GPIIb-IIIa activation and results in aggregate formation over time. Separating the PLTs from the plasma component and storing them in PAS at 4°C resolves aggregate formation and preserves the metabolic and functional responses of these stored PLTs.

Plasma can be manufactured by multiple methods. Few studies have compared quality parameters between plasma products that may affect efficacy and safety. Four different plasma products were analyzed to include fresh frozen plasma (FFP),liquid plasma (LP), solvent detergent plasma (SDP), and a spray-dried, solvent detergent - treated plasma (SD-SDP) at multiple time points of storage. Parameters measured included red blood cell, platelet, and white blood cell counts; microparticle phenotypes; thrombin generation; and thrombelastography. These parameters were compared in 10 samples of each product. SDP and SD-SDP contained the smallest number of residual cells compared with FFP and LP. Platelets were the most common residual cell in all products and were highest in LP. FFP contained the greatest number of residual red blood cells. Total microparticle counts were elevated in LP and FFP compared with SDP and SD-SDP. Cell-derived microparticles in both LP and FFP were mostly platelet in origin. Microparticle counts in SDP and SD-SDP were negligible. Thrombelastography results demonstrated similar thrombin, fibrinogen, and platelet function on Day 28 LP compared with Day 5 thawed FFP. Thrombin generation assays revealed that the total, lag time to, and peak thrombin formation were higher in SDP and SD-SDP compared with FFP and LP. All parameters in FFP and LP products were characterized by a large degree of variability. The differences in cellular, microparticle, and functional hemostatic parameters measured between plasma products have the potential to affect efficacy and safety. Further study is needed to elucidate the potential immune effects of the cellular and microparticle differences noted as well as the clinical implications of altered thrombin generation kinetics in SD products.

In planning for future contingencies, current problems often crowd out historical perspective and planners often turn to technological solutions to bridge gaps between desired outcomes and the reality of recent experience. The US Military, North Atlantic Treaty Organization, and other allies are collectively taking stock of 10-plus years of medical discovery and rediscovery of combat casualty care after the wars in Iraq and Afghanistan. There has been undeniable progress in the treatment of combat wounded during the course of the conflicts in Southwest Asia, but continued efforts are required to improve hemorrhage control and provide effective prehospital resuscitation that treats both coagulopathy and shock. This article presents an appraisal of the recent evolution in medical practice in historical context and suggests how further gains in far forward resuscitation might be achieved using existing technology and methods based on whole-blood transfusion while research on new approaches continues.

Background Many military and civilian centers have shifted to a damage-control resuscitation approach, focused on providing oxygen-carrying capacity while simultaneously mitigating coagulopathy with a balanced ratio of platelets and plasma to red blood cells. It is unclear to what degree this strategy is used during burn or soft tissue excision. Here, we characterized blood product transfusion during burn and soft tissue surgery and reviewed the published literature regarding intraoperative coagulation changes. We hypothesized that blood product resuscitation during burn and soft tissue excision is not hemostatic and would be insufficient to address hemorrhage-induced coagulopathy. Methods Consented adult patients were enrolled into an institutional review board-approved prospective observational study. Number, component type, volume, and age of the blood products transfused were recorded during burn excision/grafting or soft tissue debridement. Component bags (packed red blood cells, fresh frozen plasma, platelets, and cryoprecipitate) were collected, and the remaining sample was harvested from the bag and tubing. Aliquots of 1/1,000th the original volume of each blood product were obtained and combined, producing an amalgam sample containing the same ratio of product transfused. Platelet count, rotational thromboelastometry, and impedance aggregometry were measured. Significance was set at p Results Amalgamated transfusate samples produced abnormally weak clots (p ≤ 0.001) particularly if they did not contain platelets. Clot strength (48.8 [2.6] mm; reference range, 49-71 mm) for platelet-containing amalgams was below the lower limit of the reference range despite platelet-red blood cell ratios greater than 1:1. Platelet aggregation was abnormally low; transfused platelets were functionally inferior to native platelets. Conclusion Our study and focused review demonstrate that further work is needed to fully understand the needs of patients undergoing tissue excision. The three studies reviewed and the results of our observational work suggest that coagulopathy and thrombocytopenia may contribute to intraoperative hemorrhage. Blood product resuscitation during burn and soft tissue excision is not hemostatic. Level of evidence Epidemiologic study, level V.