A
bstract
We calculate the relevant Spencer cohomology of the minimal Poincaré superalgebra in 5 spacetime dimensions and use it to define Killing spinors via a connection on the spinor bundle of a ...5-dimensional lorentzian spin manifold. We give a definition of bosonic backgrounds in terms of this data. By imposing constraints on the curvature of the spinor connection, we recover the field equations of minimal (ungauged) 5-dimensional supergravity, but also find a set of field equations for an
sp
(1)-valued one-form which we interpret as the bosonic data of a class of rigid supersymmetric theories on curved backgrounds. We define the Killing superalgebra of bosonic backgrounds and show that their existence is implied by the field equations. The maximally supersymmetric backgrounds are characterised and their Killing superalgebras are explicitly described as filtered deformations of the Poincaré superalgebra.
Fibrinogen is crucial for the formation of blood clot and clinical outcomes in major bleeding. Both Thromboelastography (TEG) and Rotational Thromboelastometry (ROTEM) have been increasingly used to ...diagnose fibrinogen deficiency and guide fibrinogen transfusion in trauma and surgical bleeding patients. We conducted a comprehensive and comparative review on the technologies and clinical applications of two typical functional fibrinogen assays using TEG (FF TEG) and ROTEM (FIBTEM) for assessment of fibrinogen level and deficiency, and prediction of transfusion requirement. Clot strength and firmness of FF TEG and ROTEM FIBTEM were the most used parameters, and their associations with fibrinogen levels as measured by Clauss method ranged from 0 to 0.9 for FF TEG and 0.27 to 0.94 for FIBTEM. A comparison of the interchangeability and clinical performance of the functional fibrinogen assays using the two systems showed that the results were correlated, but are not interchangeable between the two systems. It appears that ROTEM FIBTEM showed better associations with the Clauss method and more clinical use for monitoring fibrinogen deficiency and predicting transfusion requirements including fibrinogen replacement than FF TEG. TEG and ROTEM functional fibrinogen tests play important roles in the diagnosis of fibrinogen-related coagulopathy and guidance of transfusion requirements. Despite the fact that high-quality evidence is still needed, the two systems are likely to remain popular for the hemostatic management of bleeding patients.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
Whole Blood Transfusion Cap, Andrew P; Beckett, Andrew; Benov, Avi ...
Military medicine,
09/2018, Volume:
183, Issue:
suppl_2
Journal Article
Peer reviewed
Open access
Whole blood is the preferred product for resuscitation of severe traumatic hemorrhage. It contains all the elements of blood that are necessary for oxygen delivery and hemostasis, in nearly ...physiologic ratios and concentrations. Group O whole blood that contains low titers of anti-A and anti-B antibodies (low titer group O whole blood) can be safely transfused as a universal blood product to patients of unknown blood group, facilitating rapid treatment of exsanguinating patients. Whole blood can be stored under refrigeration for up to 35 days, during which it retains acceptable hemostatic function, though supplementation with specific blood components, coagulation factors or other adjuncts may be necessary in some patients. Fresh whole blood can be collected from pre-screened donors in a walking blood bank to provide effective resuscitation when fully tested stored whole blood or blood components are unavailable and the need for transfusion is urgent. Available clinical data suggest that whole blood is at least equivalent if not superior to component therapy in the resuscitation of life-threatening hemorrhage. Low titer group O whole blood can be considered the standard of care in resuscitation of major hemorrhage.
Damage Control Resuscitation Cap, Andrew P; Pidcoke, Heather F; Spinella, Philip ...
Military medicine,
09/2018, Volume:
183, Issue:
suppl_2
Journal Article
Peer reviewed
Open access
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.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK, VSZLJ
ABSTRACT
Introduction
Canadian Armed Forces adopted fibrinogen concentrate (RiaSTAP) for hemostatic resuscitation in the far-forward combat setting, given its potential benefits of reducing blood ...loss, blood transfusion and mortality, and its long storage stability and high portability. The current guidance recommends that RiaSTAP should be administered within 8 hours after reconstitution when stored at room temperature. However, little information about its stability is available. There is also a need to investigate the stability and efficacy of RiaSTAP after reconstitution and exposure to extreme temperatures in which our forces may operate.
Materials and Methods
RiaSTAP was reconstituted as per manufacturer’s instruction and stored at specific temperatures (−20°C, 4°C, 22°C, 35°C, 42°C, or 50°C) for up to 6 months. Reconstituted RiaSTAP was also oscillated on a rocker at 18 rpm under 22°C and 50°C. Its hemostatic function was measured using rotational thromboelastometry performed with RiaSTAP-spiked whole blood. Fibrinogen concentrations were measured by a commercial enzyme-linked immunosorbent assay (ELISA) kit. Gel electrophoresis was also conducted for initial and stored samples.
Results
We found no change to the hemostatic function of reconstituted RiaSTAP after storage at −20°C for 6 months. At 4°C, no obvious changes to the hemostatic effect of reconstituted RiaSTAP relative to 0 hours were seen until 1,680 hours. At 22°C, a remarkable decrease began after storage for 168 hours. Storage at 35°C significantly decreased the hemostatic effect after 144 hours, while the storage at 42°C resulted in decreased hemostatic function after 72 hours. Finally, storage at 50°C for 8 hours resulted in complete loss of hemostatic function. Compared to the hemostatic activity, the fibrinogen concentration for reconstituted RiaSTAP showed less change over time. No apparent decline in fibrinogen concentration was seen after storage at −20°C for 6 months and at 4°C for 1,680 hours. At 22°C, there were no clear alterations until 792 hours. There was a decline in fibrinogen concentration at 35°C and 42°C after 672 and 600 hours of storage, respectively. At 50°C, little amount of fibrinogen was detected by ELISA at 8 hours. Similar changes in the hemostatic effect and fibrinogen concentration over time were observed under the rocking condition in comparison with the static condition at the same temperature. The gel electrophoresis confirmed fibrinogen degradation which increased with storage temperature and time.
Conclusions
The stability of reconstituted RiaSTAP decreases with increasing storage temperature. The hemostatic function deteriorated before fibrinogen concentration and integrity were significantly altered at all temperatures for the study period except at 50°C where there was a rapid decline in both hemostatic function and fibrinogen concentration. Sample oscillation did not significantly affect its stability. The shelf life of reconstituted RiaSTAP may, therefore, be recommended accordingly when stored at different temperatures and extended to 6 days at room temperature provided that sterility is maintained.
ABSTRACT
Introduction
Hemorrhage is responsible for 91% of preventable prehospital deaths in combat. Bleeding from anatomic junctions such as the groin, neck, and axillae make up 19% of these deaths, ...and reports estimate that effective control of junctional hemorrhage could have prevented 5% of fatalities in Afghanistan. Hemostatic dressings are effective but are time-consuming to apply and are limited when proper packing and manual pressure are not feasible, such as during care under fire. CounterFlow-Gauze is a hemostatic dressing that is effective without compression and delivers thrombin and tranexamic acid into wounds. Here, an advanced prototype of CounterFlow-Gauze, containing a range of low thrombin doses, was tested in a lethal swine model of junctional hemorrhage. Outcomes were compared with those of Combat Gauze, the current dressing recommended by Tactical Combat Casualty Care.
Materials and Methods
CounterFlow-Gauze containing thrombin doses of 0, 20, 200, and 500 IU was prepared. Swine received femoral arteriotomies, and CounterFlow-Gauze was packed into wounds without additional manual compression. In a separate study using a similar model of junctional hemorrhage without additional compression, CounterFlow-Gauze containing 500 IU thrombin was tested and compared with Combat Gauze. In both studies, the primary outcomes were survival to 3 h and volume of blood loss.
Results
CounterFlow-Gauze with 200 and 500 IU had the highest 3-h survival, achieving 70 and 75% survival, respectively. CounterFlow-Gauze resulted in mean peak plasma tranexamic acid concentrations of 9.6 ± 1.0 µg/mL (mean ± SEM) within 3 h. In a separate study with smaller injury, CounterFlow-Gauze with 500 IU achieved 100% survival to 3 h compared with 92% in Combat Gauze animals.
Conclusions
An advanced preclinical prototype of CounterFlow-Gauze formulated with a minimized thrombin dose is highly effective at managing junctional hemorrhage without compression. These results demonstrate that CounterFlow-Gauze could be developed into a feasible alternative to Combat Gauze for hemorrhage control on the battlefield.
Societal Costs of Inappropriate Emergency Department Thoracotomy Passos, Edward M., MD; Engels, Paul T., MD, FACS; Doyle, Jeffrey D., MD ...
Journal of the American College of Surgeons,
2012, 2012-Jan, 2012-01-00, 20120101, Volume:
214, Issue:
1
Journal Article
Peer reviewed
Background Emergency department (ED) thoracotomy can be lifesaving. It can also lead to resource waste and exposure to blood-borne infections. We investigated the frequency with which ED thoracotomy ...was performed for inappropriate indications and the resulting societal costs. Study Design This retrospective cohort study examined all trauma patients admitted directly from the scene of injury from 1992 to 2009 who underwent ED thoracotomy. The main outcomes included inappropriate ED thoracotomy. Secondary outcomes included resource use and societal costs for performing ED thoracotomy for improper indications. Specifically, we analyzed for operating room use, blood transfusions, ICU and hospital stay, needlestick injuries, survivor rate, and neurological outcomes in this group. Results One hundred and twenty-three patients underwent ED thoracotomy during the study period. Of those, 63 (51%) were considered inappropriate. In this group, we observed no survivors, none became organ donors, 3 cases of needlestick injuries to health care providers occurred, and 335 U of blood products were used in their care. Also, 4 patients of 63 survived to the operating room and required a total of 6 separate operating room visits. Three of these patients had an ICU stay of 1 day and 1 died on day 5. Conclusions ED thoracotomy should be reserved for potentially salvageable patients, but discouraged for other indications. From the societal point of view, inappropriate use of the procedure resulted in substantial costs and waste of resources, exposure of health care providers to possible blood-borne infections, and offered no survival benefit.
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GEOZS, NUK, OILJ, SBJE, UL, UPUK
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.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK