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10/11/2015

Dépakine chez le blessé cranien en choc ?

Treatment with a histone deacetylase inhibitor, valproic acid, is associated with increased platelet activation in alarge animal model of traumatic brain injury and hemorrhagic shock

Dekker SE et Al. J Surg Res. 2014 Jul;190(1):312-8

 

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Le concept du damaged control resuscitation fait appel en partie à de nouvelles modalités transfusionnelles et d'emploi de fractions coagulantes. D'autres approches sont possibles comme celles visant à restuarer la fonction plaquettaire. C'est ce que permettrait l'adminsitration de médicaments appartenant à la classe des inhibiteurs des histone deacetylase et dont les effets neuroprotecteurs pourraient ainsi être mis à profit.  Le document proposé semble conforter cette approche.

Documents reliés: 1, 2, 3

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BACKGROUND:

We have previously shown that resuscitation with fresh frozen plasma (FFP) in a large animal model of traumatic brain injury (TBI) and hemorrhagic shock (HS) decreases the size of the brain lesion, and that addition of a histone deacetylase inhibitor, valproic acid (VPA), provides synergistic benefits. In this study, we hypothesized that VPA administration would be associated with a conservation of platelet function as measured by increased platelet activation after resuscitation.

MATERIALS AND METHODS:

Ten swine (42-50 kg) were subjected to TBI and HS (40% blood loss). Animals were left in shock for 2 h before resuscitation with either FFP or FFP+VPA (300 mg/kg). Serum levels of platelet activation markers transforming growth factor beta, CD40 L, P-selectin, and platelet endothelial cell adhesion molecule (PECAM) 1 were measured at baseline, postresuscitation, and after a 6-h observation period. Platelet activation markers were also measured in the brain whole cell lysates and immunohistochemistry.

RESULTS:

Circulating P-selectin levels were significantly higher in the FFP+VPA group compared with the FFP alone group (70.85±4.70 versus 48.44±7.28 ng/mL; P<0.01). Likewise, immunohistochemistry data showed elevated P-selectin in the VPA treatment group (22.30±10.39% versus 8.125±3.94%, P<0.01). Serum sCD40L levels were also higher in the FFP+VPA group (3.21±0.124 versus 2.38±0.124 ng/mL; P<0.01), as was brainsCD40L levels (1.41±0.15 versus 1.22±0.12 ng/mL; P=0.05). Circulating transforming growth factor beta levels were elevated in the FFP+VPA group, but this did not reach statistical significance (11.20±1.46 versus 8.09±1.41 ng/mL; P=0.17). Brain platelet endothelial cell adhesion molecule 1 levels were significantly lower in the FFP+VPA group compared with the FFP group (5.22±2.00 pg/mL versus 7.99±1.13 pg/mL; P=0.03).

CONCLUSIONS:

In this clinically relevant large animal model of combined TBI+HS, the addition of VPA to FFP resuscitation results in an early upregulation of platelet activation in the circulation and the brain. The previously observed neuroprotective effects of VPA may be due to a conservation of platelet function as measured by a higher platelet activation response after resuscitation.

| Tags : tbi, coagulopathie

09/11/2015

Plaie cérébrale et coagulopathie

Quelques faits

1. Elle est fréquente voire très fréquente: Greuters et al. Critical Care 2011 15:R2   doi:10.1186/cc9399 

cc9399-1.jpg 

2. Elle est + fréquente en cas d'hypoTA: Wafaisade  Neurocrit Care. 2010 Apr;12(2):211-9

COT TBI.jpg

3. Elle est de mauvais pronostic: J Emerg Trauma Shock. 2013 Jul-Sep; 6(3): 180–185

JETS-6-180-g002.jpg

4. Elle est mise en évidence plutôt par thromboélastographie (r TEG) : Sixta al., J Neurol Neurophysiol 2014, 6:5

rTEG TBI Coagulopathy.jpg

Un point plus complet

| Tags : coagulopathie

08/11/2015

Damage Control: Vraiment bénéfique

Changing Patterns of In-Hospital Deaths Following Implementation of Damage Control Resuscitation Practices in US Forward Military Treatment Facilities

Langan NR et Al. JAMA Surg. 2014;149(9):904-912

Importance

Analysis of combat deaths provides invaluable epidemiologic and quality-improvement data for trauma centers and is particularly important under rapidly evolving battlefield conditions.

Objective

To analyze the evolution of injury patterns, early care, and resuscitation among patients who subsequently died in the hospital, before and after implementation of damage control resuscitation (DCR) policies.

Design, Setting, and participants

In a review of the Joint Theater Trauma Registry (2002-2011) of US forward combat hospitals, cohorts of patients with vital signs at presentation and subsequent in-hospital death were grouped into 2 time periods: pre-DCR (before 2006) and DCR (2006-2011).

Main outcomes and measures

Injury types and Injury Severity Scores (ISSs), timing and location of death, and initial (24-hour) and total volume of blood products and fluid administered.

Results 

Of 57 179 soldiers admitted to a forward combat hospital, 2565 (4.5%) subsequently died in the hospital. The majority of patients (74%) were severely injured (ISS > 15), and 80% died within 24 hours of admission. Damage control resuscitation policies were widely implemented by 2006 and resulted in a decrease in mean 24-hour crystalloid infusion volume (6.1-3.2 L) and increased fresh frozen plasma use (3.2-10.1 U) (both P < .05) in this population. The mean packed red blood cells to fresh frozen plasma ratio changed from 2.6:1 during the pre-DCR period to 1.4:1 during the DCR period (P < .01). There was a significant increase in mean ISS between cohorts (pre-DCR ISS = 23 vs DCR ISS = 27; P < .05) and a marked shift in injury patterns favoring more severe head trauma in the DCR cohort.

DCR BeforeAfter.jpg

Conclusions and relevance

There has been a significant shift in resuscitation practices in forward combat hospitals indicating widespread military adoption of DCR. Patients who died in a hospital during the DCR period were more likely to be severely injured and have a severe brain injury, consistent with a decrease in deaths among potentially salvageable patients

 

 

| Tags : remplissage

02/11/2015

Mg++: Médicament de la coagulopathie ?

Both acute delivery of and storage with magnesium sulfate promote cold-stored platelet aggregation and coagulation function

Meledeo MA et Al. J Trauma Acute Care Surg. 2015 Oct;79(4 Suppl 2):S139-45

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Il y a quelque mois était publié un travail de recherche portant sur  l'intérêt de l'administration de Adénosine/Lidocaïne/Mg2+ ALM (1, 2, 3). Une hypothèse faite par les auteurs  serait que L'ALM agirait comme un antifibrinolytique en activant la voie du thrombin-activatable fibrinolysis inhibitor (TAFI) plutôt que celle de la protéine C. Cette action passerait par un mécanisme antiinflammatoire, une modification de la polarité endothéliale et une action sur la fonction plaquettaire. Le travail expérimental dont l'abstract est présenté met en avant l'intérêt de l'adminsitration de magnésium pour la restauration de la fonction plaquettaire après conservation de palquettes d'aphérèse au delà de 5 jours.

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BACKGROUND:

The platelet storage lesion causes loss of function and viability over time. A new paradigm for platelet storage is desired to enable safer, more effective transfusions while reducing waste. We hypothesized that repletion of Mg, which is chelated by citrate anticoagulant, could reduce platelet storage lesion severity when given in conjunction with storage at a refrigerated temperature.

METHODS:

Apheresis platelet units were collected from healthy donors and stored at 22°C or 4°C. On Days 0, 2, 4, and 8, samples were collected for analyses of receptor-mediated aggregation, coagulation, adhesion to collagen under flow, and viability. In the first series, samples were given anacute dose of MgSO4 before testing; in the second series, storage bags were supplemented with 0-, 3-, or 6-mM MgSO4.

RESULTS:

Acutely delivered MgSO4 induced a more rapid coagulation time in apheresis platelets, further enhanced by storage at 4°C. Plateletadhesion to a collagen surface while exposed to arterial shear rates (920 s) was enhanced by MgSO4 supplementation-acute MgSO4 had a large effect on adhesion of fresh platelets, which diminished more rapidly in 22°C samples, while storage with MgSO4 showed significant benefits even out to Day 4 at both temperatures. Although 4°C storage improves the longevity of platelet aggregation responses to agonists, MgSO4 supplementation did not change those responses.

CONCLUSION:

Acute MgSO4 reduces clot time likely through the transient increase of free Ca. Limited differences between platelet function inacute delivery of and storage with MgSO4 diminish the possibility that Mg-induced metabolic inhibition of platelets synergizes with 4°C storage. Regardless, magnesium supplementation to platelets is an exciting possibility in transfusion because the adhesion response of 22°C-stored platelets on Day 4 is significantly enhanced when stored with 6-mM MgSO4

| Tags : coagulopathie

18/09/2015

Coagulopathie traumatique: Mécanismes

Trauma-Induced Coagulopathy: An Institution's 35 Year Perspective on Practice and Research

Gonzales E. et Al. Scandinavian Journal of Surgery 103: 89–103, 2014

TraumaCoag.jpg

| Tags : coagulopathie

03/07/2015

Fibrinogène avec le TXA ?: Plutôt oui

Association of Cryoprecipitate and Tranexamic Acid With Improved Survival Following Wartime Injury: Findings From the MATTERs II Study

Morrison JJ et Al. JAMA Surg. 2013;148(3):218-225.

 

Objective To quantify the impact of fibrinogen-containing cryoprecipitate in addition to the antifibrinolytic tranexamic acid on survival in combat injured.

Design Retrospective observational study comparing the mortality of 4 groups: tranexamic acid only, cryoprecipitate only, tranexamic acid and cryoprecipitate, and neither tranexamic acid nor cryoprecipitate. To balance comparisons, propensity scores were developed and added as covariates to logistic regression models predicting mortality.

Setting A Role 3 Combat Surgical Hospital in southern Afghanistan.

Patients A total of 1332 patients were identified from prospectively collected UK and US trauma registries who required 1 U or more of packed red blood cells and composed the following groups: tranexamic acid (n = 148), cryoprecipitate (n = 168), tranexamic acid/cryoprecipitate (n = 258), and no tranexamic acid/cryoprecipitate (n = 758).

Main Outcome Measure In-hospital mortality.

Results Injury Severity Scores were highest in the cryoprecipitate (mean [SD], 28.3 [15.7]) and tranexamic acid/cryoprecipitate (mean [SD], 26 [14.9]) groups compared with the tranexamic acid (mean [SD], 23.0 [19.2]) and no tranexamic acid/cryoprecipitate (mean [SD], 21.2 [18.5]) (P < .001) groups. Despite greater Injury Severity Scores and packed red blood cell requirements, mortality was lowest in the tranexamic acid/cryoprecipitate (11.6%) and tranexamic acid (18.2%) groups compared with the cryoprecipitate (21.4%) and no tranexamic acid/cryoprecipitate (23.6%) groups. Tranexamic acid and cryoprecipitate were independently associated with a similarly reduced mortality (odds ratio, 0.61; 95% CI, 0.42-0.89; P = .01 and odds ratio, 0.61; 95% CI, 0.40-0.94; P = .02, respectively). The combined tranexamic acid and cryoprecipitate effect vs neither in a synergy model had an odds ratio of 0.34 (95% CI, 0.20-0.58; P < .001), reflecting nonsignificant interaction (P = .21).

Conclusions Cryoprecipitate may independently add to the survival benefit of tranexamic acid in the seriously injured requiring transfusion. Additional study is necessary to define the role of fibrinogen in resuscitation from hemorrhagic shock.

 

| Tags : coagulopathie

07/02/2015

RFE Choc hémorragique

rfe ChocHem.jpg

 Clic sur l'image pour accéder au document

| Tags : choc, hémorragie

30/10/2014

Plaquettes synthétiques: Possible ? Mais oui

Tuning Ligand Density on Intravenous Hemostatic Nanoparticles Dramatically Increases Survival Following Blunt Trauma

Proc Natl Acad Sci U S A. 2014 Jul 15;111 (28) 10293-10298

Des plaquettes synthétiques pour arrêter le saignement ? Certains l'ont fait grâce à la technologie des nanoparticules (1, 2). Un espoir qui reste à confirmer.

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Explosions account for 79% of combat-related injuries, leading to multiorgan hemorrhage and uncontrolled bleeding. Uncontrolled bleeding is the leading cause of death in battlefield traumas as well as in civilian life. We need to stop the bleeding quickly to save lives, but, shockingly, there are no treatments to stop internal bleeding. A therapy that halts bleeding in a site-specific manner and is safe, stable at room temperature, and easily administered is critical for the advancement of trauma care. To address this need, we have developed hemostatic nanoparticles that are administered intravenously. When tested in a model of blast trauma with multiorgan hemorrhaging, i.v. administration of the hemostatic nanoparticles led to a significant improvement in survival over the short term (1 h postblast). No complications from this treatment were apparent out to 3 wk. This work demonstrates that these particles have the potential to save lives and fundamentally change trauma care.

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| Tags : hémorragie

21/11/2013

Le plasma lyophilisé: Bon pour le cerveau du traumatisé qui saigne

Early treatment with lyophilized plasma protects the brain in a large animal model of combined traumatic brain injury and hemorrhagic shock

Imam AM et Al. J Trauma Acute Care Surg. 2013;75: 976-983

accéder aux abstracts de la WTA publiés dans J trauma Acute care

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Bien sûr une étude animale, mais une de plus qui milite pour un emploi précoce du plasma lyophylisé.

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BACKGROUND: Combination of traumatic brain injury (TBI) and hemorrhagic shock (HS) can result in significant morbidity and mortality. We have previously shown that early administration of fresh frozen plasma (FFP) in a large animal model of TBI and HS reduces the size of the brain lesion as well as the associated edema. However, FFP is a perishable product that is not well suited for use in the austere prehospital settings. In this study, we tested whether a shelf-stable, low-volume, lyophilized plasma (LSP) product was as effective as FFP.

METHODS:

Yorkshire swine (42-50 kg) were instrumented to measure hemodynamic parameters, intracranial pressure, and brain tissue oxygenation. A prototype, computerized, cortical impact device was used to create TBI through a 20-mm craniotomy: 15-mm cylindrical tipimpactor at 4 m/s velocity, 100-millisecond dwell time, and 12-mm penetration depth. Volume-controlled hemorrhage was induced(40-45% total blood volume) concurrent with the TBI. After 2 hours of shock, animals were treated with (1) normal saline (NS, n = 5), (2) FFP (n = 5), and (3) LSP (n = 5). The volume of FFP and LSP matched the shed blood volume, whereas NS was 3 times the volume. Six hours after resuscitation, brains were sectioned and stained with TTC (2, 3, 5-Triphenyltetrazolium chloride), and lesion size (mm3) and swelling (percent change in volume compared with the contralateral, uninjured side) were measured.

RESULTS:

This protocol resulted in a highly reproducible brain injury, with clinically relevant changes in blood pressure, cardiac output, tissue hypoperfusion, intracranial pressure, and brain tissue oxygenation. Compared with NS, treatment with LSP significantly ( p G 0.05) decreased brain lesion size and swelling (51% and 54%, respectively).

LSP.jpg

CONCLUSION: In a clinically realistic combined TBI + HS model, early administration of plasma products decreases brain lesion size and edema. LSP is as effective as FFP, while offering many logistic advantages. 

| Tags : tbi, coagulopathie

07/08/2013

Plasma: En préhospitalier AUSSI +++

Point-of-injury use of reconstituted freeze dried plasma as a resuscitative fluid: A special report for prehospital trauma care

Glassberg E. et All. J J Trauma Acute Care Surg. 2013;75(Suppl 2):S111YS111.

La prise en charge d'hémorrragie catastrophique en phase préhospitalière est particulièrement complexe. Ces dernières années la mise en place d'un réseau structuré de prise en charge, 'application de procédures spécifiques visant à arrêter les hémorragies au plus tôt, le recours à l'acide tranexaminique, la prévention des hypothermies et l'application d'une politique raisonnée de rénaimation/chirurgie ont constitué une grande avancée. Certaines nations ont équipé leurs vecteurs d'évacuations de concentrés érythrocytaires. Le maintien d'une coagulation optimale est un enjeu majeur. Pour cela existe, entre autres,  le plasma lyophilisé. Les forces armées israéliennes militent pour l'emploi de ce type de solutions en phase préhospitalière

16/07/2013

Management of bleeding and coagulopathy following major trauma: an updated European guideline

hémorragie,traumatologie

Accéder aux recommandations

29/06/2013

Coagulopathie du trauma: Que faire ?

 Case Scenario: Management of Trauma-induced Coagulopathy in a Severe Blunt Trauma Patient

David JS et All. Anesthesiology 2013; 119:191–200 

CoagulopathieTrauma.jpeg

Un point très clair du problème

| Tags : coagulopathie

02/12/2012

Hémostase et transfusion par A. Godier IAR IDF

iar.JPG

CLIC sur le logo pour accéder au cours

| Tags : hémorragie

Choc hémorragique par D. Journois IAR IDF

iar.JPG

CLIC sur le logo pour visualiser le cours

01/12/2012

Apport du fibrinogène: A la folie ou pas du tout ??

Une econférence qui fait parfaitement le point sur l'intérêt et les questions en suspens concernant l'intérêt du fibrinogène dans la réanimation hémostatique du traumasié qui saigne.

Fibrinogène.JPG

En condition de combat avant l'arivée en structure hopsitalière de campagne, l'apport de fibrinogène peut être réalisé par l'apport de plasma lyophylisé (PLYO) produit par le SSA (obtenu en moins de 6 min après reconstitution à température ambiante par adjonction d'eau PPI, chaque unité contient au moins 0,5g de fibrinogène). C'est une des composantes de la transfusion de plasma thérapeutique. qui doit désormais être envisagé au niveau du role 1 (poste de secours ou vecteur d'évacuation tactique).

Le recours au fibrinogène (Clottafact), qui apparaît être d'un intérêt majeur compte tenu d'un apport insuffisant par la transfusion de plasma. (Abstract Rourke et all.)

coagulopathie

Il ne peut (pour des raisons de logistique de production et de disponibilté) être apporté qu'à partir de la prise en charge hospitalière.

Pour approfondir avec en perspective le blessé de guerre hémorragique:

(1) Un revue générale sur la coagulopathie de l'hémorragie massive: "Hemodilution caused by trauma and major surgery induces complex hemostatic changes involving procoagulant factors as well as anticoagulant, fibrinolytic, and antifibrinolytic factors. The endothelial responses to shear stress, active proteases, and various inflammatory cells and cytokines add further complexity to the pathophysiology of massive hemodilution. In addition to the conventional transfusion products, which are often difficult to administer in a timely manner, purified factor concentrates of plasma origin and from recombinant synthesis are highly concentrated (i.e., small volume) for a rapid restoration of targeted factor(s). The use of point-of-care testing is desirable to optimize the dose and timing of such intervention. Additional clinical trials of different factor concentrate therapies are required to validate their efficacy and safety in patients after trauma or major surgery.152 Further understanding of the time course of pathophysiological changes in massive hemodilution is necessary to optimally balance hemostatic and anticoagulant therapies."

(2) Un focus sur le blessé de guerre: "In patients with combatrelated trauma requiring massive transfusion, the transfusion of an increased fibrinogen: RBC ratio was independently associated with improved survival to hospital discharge, primarily by decreasing death from hemorrhage. Prospective studies are needed to evaluate the best source of fibrinogen and the optimal empiric ratio of fibrinogen to RBCs in patients requiring massive transfusion."

(3) La stratégie transfusionnelle du blessé de guerre SFAR 2012: " En traumatologie, l’administration de fibrinogène est recommandée : dose initiale de 3 à 4 g suivie d’une administration régulière en cas d’hypofibrinogènémie biologique (<1,5 à 2 g/l) ou de signes thromboelastométriques de déficit fonctionnel en fibrinogène [8]. Une analyse nord-américaine rétrospective de 252 dossiers de BdG ayant nécessité une TM a permis de mettre en évidence qu’un apport faible de fibrinogène (< 0,2 g/CGR) au cours de la transfusion était associé à une majoration significative de la mortalité de ces blessés [39]. Le SSA américain utilise l’apport de cryoprécipités contenant surtout du fibrinogène et d’autres facteurs de coagulation pour compenser ces déficits [37]. Les recommandations du SSA français sont l’administration de fibrinogène de façon répétée afin de maintenir un fibrinogène plasmatique supérieur à 1,5 g/l ou en l’absence de laboratoire (situation des structures chirurgicales « légères »), d’administrer au moins 0,2 g de fibrinogène par CGR transfusé."

| Tags : coagulopathie

23/09/2012

Facteur VIIa: Intérêt pas prouvé !

Use of recombinant factor VIIA for control of combat-related haemorrhage.

Woodruff SI et all. Emerg Med J 2010;27:2 121-124

Ce travail  met en exergue que le recours au FVIIa n'a pas d'intérêt prouvé en cas de prise en charge de traumatismes pénétrants. Ceci est d'autant plus vrai qu'il est fait alors qu'une coagulopathie sévère est installée (The utility of recombinant factor VIIa as a last resort in trauma. Mamtani R. et all. World Journal of Emergency Surgery 2012, 7(Suppl 1):S7)

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Background 

Recombinant activated human coagulation factor VII (rFVIIa), an intravascular strategy to promote clotting, is being used as an adjunct to surgical control of bleeding in combat trauma patients.

Objective 

To describe the initial experiences with rFVIIa administered to combat casualties at US Navy-Marine Corps medical treatment facilities in Iraq, and to comparesurvival outcomes of those treated with rFVIIa to controls not receiving rFVIIa.

Methods

Medical encounter data from the US Navy-Marine Corps Combat Trauma Registry were retrospectively reviewed to identify all battle-injured patients documented as having received rFVIIa during the period May 2004 to January 2006 of Operation Iraqi Freedom. Available clinical and injury related data are presented to characterise the patients. To assess effects of rFVIIa on survival outcomes, rFVIIa cases were matched to controls on injury severity and age.

Results 

22 battle-injured patients from the Combat Trauma Registry received rFVIIa. Primarily young US Marines, these patients typically had penetrating injuries from improvised explosive devices and gunshot wounds. Injuries were often abdominal. The average dose used was similar to that reported in another study of civilian trauma patients, although dosing varies widely in the existing experimental and anecdotal literature. Over two-thirds (68%) of the rFVIIa patients surviveddan identical outcome seen for a matched control group of 22 patients.

Conclusions 

Survival of seriously injured combat casualties was good, although identical to that of a control group. Methodological limitations of this retrospective study preclude making firm conclusions about the effectiveness of rFVIIa. Future controlled studies are needed for safety and efficacy testing of rFVIIa in combat trauma patients.

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29/03/2011

Exacyl: OUI mais dans l'heure qui suit le trauma

L'exacyl est recommandé pour la prise en charge du traumatisé. L'étude Crash 2 l'a montré. Un complément d'analyse de cette étude précise cependant qu'il faut l'administer dans l'heure suivant le traumatisme.

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The importance of early treatment with tranexamic acid in bleeding trauma patients: an exploratory analysis of the CRASH-2 randomised controlled trial

Findings

10 096 patients were allocated to tranexamic acid and 10 115 to placebo, of whom 10 060 and 10 067, respectively, were analysed. 1063 deaths (35%) were due to bleeding. We recorded strong evidence that the effect of tranexamic acid on death due to bleeding varied according to the time from injury to treatment (test for interaction p<0·0001). Early treatment (≤1 h from injury) significantly reduced the risk of death due to bleeding (198/3747 [5·3%] events in tranexamic acid group vs 286/3704 [7·7%] in placebo group; relative risk [RR] 0·68, 95% CI 0·57—0·82; p<0·0001). Treatment given between 1 and 3 h also reduced the risk of death due to bleeding (147/3037 [4·8%] vs 184/2996 [6·1%]; RR 0·79, 0·64—0·97; p=0·03). Treatment given after 3 h seemed to increase the risk of death due to bleeding (144/3272 [4·4%] vs103/3362 [3·1%]; RR 1·44, 1·12—1·84; p=0·004). We recorded no evidence that the effect of tranexamic acid on death due to bleeding varied by systolic blood pressure, Glasgow coma score, or type of injury.

Interpretation

Tranexamic acid should be given as early as possible to bleeding trauma patients. For trauma patients admitted late after injury, tranexamic acid is less effective and could be harmful.

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