Un rêve d’enfant »

Ellroy, Selby Jr., Hopper pour les sources d’inspiration, Bessie Smith, Pasteur, Rachmaninov, le Portugal pour les sujets… Aude Samama circule avec aisance entre univers personnel et travaux de commandes, pliant le monde à une vision tragique qui emprunte des formes volontiers expressionnistes

Transfusion massive et coagulopathie-: physiopathologie et implications cliniques

Purpose: To review the pathophysiology of coagulopathy in massively transfused, adult and previously hemostatically competent patients in both elective surgical and trauma settings, and to recommend the most appropriate treatment strategies. Methods: Medline was searched for articles on "massive transfusion,” "transfusion,” "trauma,” "surgery,” "coagulopathy” and "hemostatic defects.” A group of experts reviewed the findings. Principal findings: Coagulopathy will result from hemodilution, hypothermia, the use of fractionated blood products and disseminated intravascular coagulation. The clinical significance of the effects of hydroxyethyl starch solutions on hemostasis remains unclear. Maintaining a normal body temperature is a first-line, effective strategy to improve hemostasis during massive transfusion. Red cells play an important role in coagulation and hematocrits higher than 30% may be required to sustain hemostasis. In elective surgery patients, a decrease in fibrinogen concentration is observed initially while thrombocytopenia is a late occurrence. In trauma patients, tissue trauma, shock, tissue anoxia and hypothermia contribute to the development of disseminated intravascular coagulation and microvascular bleeding. The use of platelets and/or fresh frozen plasma should depend on clinical judgment as well as the results of coagulation testing and should be used mainly to treat a clinical coagulopathy. Conclusions: Coagulopathy associated with massive transfusion remains an important clinical problem. It is an intricate, multifactorial and multicellular event. Treatment strategies include the maintenance of adequate tissue perfusion, the correction of hypothermia and anemia, and the use of hemostatic blood products to correct microvascular bleeding. Objectif: Revoir la physiopathologie de la coagulopathie chez les adultes transfusés massivement et auparavant compétents sur le plan hémostatique, à la fois dans le contexte ďune intervention chirurgicale réglée ou à la suite ďun traumatisme. Recommander les stratégies thérapeutiques les plus appropriées. Méthode: Dans Medline, nous avons cherché les articles traitant de "massive transfusion,” "transfusion,” "trauma,” "surgery,”"coagulopathy” et "hemostatic defects.” Un groupe ďexperts a examiné les résultats. Constatations principales: La coagulopathie résulte de ľhémodilution, ľhypothermie, ľusage de produits sanguins fractionnés et la coagulation intravasculaire disséminée. La portée clinique des effets des solutions ďhydroxyéthyl-amidon sur ľhémostase n'est toujours pas claire. Le maintien ďune température corporelle normale est une stratégie de première intention efficace pour améliorer ľhémostase pendant la transfusion massive. Les globules rouges sont importants dans la coagulation et des hématocrites supérieurs è 30 % pourraient être nécessaires à une hémostase adéquate. Chez les patients en chirurgie réglée, une baisse de la concentration de fibrinogène est observée précocement tandis que la thrombocytopénie est plus tardive. Chez les traumatisés, le trauma tissulaire, le choc, ľanoxie et ľhypothermie tissulaires contribuent au développement ďune coagulation intravasculaire disséminée et du saignement microvasculaire. Ľutilisation de plaquettes et/ou de plasma frais congelé dépendra du jugement du clinicien ainsi que des résultats des tests de coagulation. La transfusion devra surtout viser le traitement ďune coagulopathie clinique (saignement microvasculaire). Conclusion: La coagulopathie associée à la transfusion massive demeure un important problème clinique. C'est un événement complexe, multifactoriel et multicellulaire. Le traitement comprend le maintien ďune perfusion tissulaire adéquate, la correction de ľhypothermie et de ľanémie et ľusage de produits sanguins hémo-statiques pour corriger le saignement microvasculair

Traitement de la maladie thromboembolique veineuse

Purpose: To describe the drugs used to treat venous thromboembolism (VTE) and to review particular aspects of the management (elastic stockings, thrombolysis, thrombectomy, vena cava filter). Source: Our review of the literature is focused on consensus documents and recent large randomized trials. Principal findings: Subcutaneous low molecular weight heparins (LMWH) have been shown to be both safe and effective for the initial treatment of VTE and have largely replaced unfractionated heparin, unless there is a contraindication to LMWH such as severe renal insufficiency. Low molecular weight heparins or unfractionated heparin are usually administered for five to seven days. Treatment is gradually switched from heparin to oral vitamin K antagonists (VKA) which are usually started the same day as heparin. The duration of oral anticoagulation must be tailored to the individual patient according to the presence of reversible or continuing risk factors. In patients with active cancer, long-term treatment of VTE with LMWH has been shown to be more effective than oral anticoagulation and is recommended for the first three to six months of long-term anticoagulant therapy as an alternative approach to VKA. Elastic stockings are recommended because they have been shown to prevent postthrombotic syndrome. Thrombolysis is, usually, not justified for the treatment of deep venous thrombosis, but is used in cases of massive pulmonary embolism with arterial hypotension and/or shock. Vena cava filter placement is mainly indicated in patients with a proximal deep venous thrombosis and an absolute contraindication to anticoagulation. Conclusions: The initial management of patients with acute VTE has largely been simplified due to the use of LMWH. Early conversion to VKA is recommended for the great majority of patients. New agents, such as anti-Xa or oral thrombin inhibitors, are promising alternatives to heparins or VKA. Objectif: Présenter les médicaments utilisés pour traiter la maladie thromboembolique veineuse (MTEV) et revoir des aspects particuliers de la thérapie comme les bas élastiques, la thrombolyse, la thrombectomie et le filtre cave. Source: Revue de documents de consensus et de grandes études récentes. Constatations principales: Les héparines de bas poids moléculaire (HBPM) sont sûres et efficaces comme traitement initial de la MTEV et remplacent largement ľhéparine non fractionnée, à moins ďune contre-indication à ľHBPM comme ľinsuffisance rénale sévère. Les HBPM ou ľhéparine non fractionnée sont habituellement administrées pendant cinq à sept jours. Puis, on passe graduellement de ľhéparine à la prise orale ďantagonistes de la vitamine K (AVK), débutés en général le même jour que ľhéparine. La durée de ľanticoagulation orale doit être adaptée au patient en fonction de facteurs de risque réversible ou continu. Dans les cas de cancer actif, le traitement de la MTEV avec ľHBPM s'est montré plus efficace que ľanticoagulation orale et il est recommandé pour les trois à six premiers mois de traitement. Les bas élastiques sont recommandés pour prévenir le syndrome post-thrombotique. La thrombolyse n'est pas habituellement justifiée pour traiter la thrombose veineuse profonde, mais est utilisée en cas ďembolie pulmonaire massive avec hypotension et/ou choc artériels. La mise en place ďun filtre cave est principalement indiquée chez les patients souffrant de thrombose veineuse profonde proximale chez qui ľanticoagulation est une contre-indication absolue. Conclusion: Le traitement initial des patients atteints de MTEV a été grandement simplifié avec ľusage de ľHBPM. Le passage précoce aux AVK est recommandé pour la grande majorité des patients. De nouveaux médicaments comme les anti-Xa ou les inhibiteurs de la thrombine oraux, sont des équivalents prometteurs des héparines ou des AV

Updates in the perioperative and emergency management of non-vitamin K antagonist oral anticoagulants.

Perioperative management of patients treated with the non-vitamin K antagonist oral anticoagulants is an ongoing challenge. Due to the lack of good clinical studies involving adequate monitoring and reversal therapies, management requires knowledge and understanding of pharmacokinetics, renal function, drug interactions, and evaluation of the surgical bleeding risk. Consideration of the benefit of reversal of anticoagulation is important and, for some low risk bleeding procedures, it may be in the patient's interest to continue anticoagulation. In case of major intra-operative bleeding in patients likely to have therapeutic or supra-therapeutic levels of anticoagulation, specific reversal agents/antidotes would be of value but are currently lacking. As a consequence, a multimodal approach should be taken which includes the administration of 25 to 50 U/kg 4-factor prothrombin complex concentrates or 30 to 50 U/kg activated prothrombin complex concentrate (FEIBA®) in some life-threatening situations. Finally, further studies are needed to clarify the ideal therapeutic intervention

Dabigatran etexilate for thromboprophylaxis in over 5000 hip or knee replacement patients in a real-world clinical setting

BACKGROUND: Thromboprophylaxis is recommended for patients undergoing total hip or total knee replacement (THR, TKR). An international, open-label, prospective, observational, single-arm study in a routine clinical setting was performed to assess the safety and efficacy of dabigatran etexilate 220 mg once daily in patients undergoing THR or TKR, and in subgroups of patients with potentially increased risk of bleeding or venous thromboembolism (VTE). MATERIALS AND METHODS: Patients were ≥18 years and required to be eligible to receive dabigatran 220 mg once daily (first dose 110 mg 1–4 h after THR/TKR surgery) according to the European Summary of Product Characteristics. The primary safety and efficacy outcomes were incidence of major bleeding events (MBEs), and the composite incidence of symptomatic VTE events and all-cause mortality, respectively. RESULTS: In total, 5292 patients (median age 64 years) were enrolled and received dabigatran (2734 THR and 2558 TKR). Median drug exposure was 31 days (THR 34 days; TKR 27 days). Overall incidence of MBEs was 0.72 % (95 % confidence interval [CI] 0.51, 0.98), and this rate was comparable between types of surgery and was not significantly affected by protocol-defined risk factors. The overall incidence of symptomatic VTE and all-cause mortality was 1.04 % (95 % CI 0.78, 1.35); the only significant risk factor was history of VTE events (odds ratio 5.59; 95 % CI 2.53, 11.08). A post-hoc analysis showed that the incidence of MBEs in this observational study was similar to or lower than those reported in previous phase 3 trials. CONCLUSIONS: Results from this observational study of dabigatran etexilate administered to patients undergoing THR or TKR surgery are reassuring and supportive of those obtained in dabigatran phase 3 trials. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00846807. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12959-016-0082-4) contains supplementary material, which is available to authorized users

Cancer and thrombosis: Managing the risks and approaches to thromboprophylaxis

Patients with cancer are at increased risk of venous thromboembolism (VTE) compared with patients without cancer. This results from both the prothrombotic effects of the cancer itself and iatrogenic factors, such as chemotherapy, radiotherapy, indwelling central venous devices and surgery, that further increase the risk of VTE. Although cancer-associated thrombosis remains an important cause of morbidity and mortality, it is often underdiagnosed and undertreated. However, evidence is accumulating to support the use of low-molecular-weight heparins (LMWHs) in the secondary prevention of VTE in patients with cancer. Not only have LMWHs been shown to be at least as effective as coumarin derivatives in this setting, but they have a lower incidence of complications, including bleeding, and are not associated with the practical problems of warfarin therapy. Furthermore, a growing number of studies indicate that LMWHs may improve survival among patients with cancer due to a possible antitumor effect. Current evidence suggests that LMWHs should increasingly be considered for the long-term management of VTE in patients with cancer

Guideline-concordant administration of prothrombin complex concentrate and vitamin K is associated with decreased mortality in patients with severe bleeding under vitamin K antagonist treatment (EPAHK study).

International audienceINTRODUCTION: In vitamin K antagonist (VKA)-treated patients with severe hemorrhage, guidelines recommend prompt VKA reversal with prothrombin complex concentrate (PCC) and vitamin K. The aim of this observational cohort study was to evaluate the impact of guideline concordant administration of PCC and vitamin K on 7-day mortality. METHODS: Data from consecutive patients treated with PCC were prospectively collected in 44 emergency departments. Type of hemorrhage, coagulation parameters, type of treatment and 7-day mortality were recorded. Guideline-concordant administration of PCC and vitamin K (GC-PCC-K) were defined by at least 20 IU/kg factor IX equivalent PCC and at least 5 mg of vitamin K performed within a predefined time frame of 8 hours after admission. Multivariate analysis was used to assess the effect of appropriate reversal on 7-day mortality in all patients and in those with intracranial hemorrhage (ICH). RESULTS: Data from 822 VKA-treated patients with severe hemorrhage were collected over 14 months. Bleeding was gastrointestinal (32%), intracranial (32%), muscular (13%), and "other" (23%). In the whole cohort, 7-day mortality was 13% and 33% in patients with ICH. GC-PCC-K was performed in 38% of all patients and 44% of ICH patients. Multivariate analysis showed a two-fold decrease in 7-day mortality in patients with GC-PCC-K (odds ratio (OR) = 2.15 (1.20 to 3.88); P = 0.011); this mortality reduction was also observed when only ICH was considered (OR = 3.23 (1.53 to 6.79); P = 0.002). CONCLUSIONS: Guideline-concordant VKA reversal with PCC and vitamin K within 8 hours after admission was associated with a significant decrease in 7-day mortality

Elevated hemostasis markers after pneumonia increases one-year risk of all-cause and cardiovascular deaths

Background: Acceleration of chronic diseases, particularly cardiovascular disease, may increase long-term mortality after community-acquired pneumonia (CAP), but underlying mechanisms are unknown. Persistence of the prothrombotic state that occurs during an acute infection may increase risk of subsequent atherothrombosis in patients with pre-existing cardiovascular disease and increase subsequent risk of death. We hypothesized that circulating hemostasis markers activated during CAP persist at hospital discharge, when patients appear to have recovered clinically, and are associated with higher mortality, particularly due to cardiovascular causes. Methods: In a cohort of survivors of CAP hospitalization from 28 US sites, we measured D-Dimer, thrombin-antithrombin complexes [TAT], Factor IX, antithrombin, and plasminogen activator inhibitor-1 at hospital discharge, and determined 1-year all-cause and cardiovascular mortality. Results: Of 893 subjects, most did not have severe pneumonia (70.6% never developed severe sepsis) and only 13.4% required intensive care unit admission. At discharge, 88.4% of subjects had normal vital signs and appeared to have clinically recovered. D-dimer and TAT levels were elevated at discharge in 78.8% and 30.1% of all subjects, and in 51.3% and 25.3% of those without severe sepsis. Higher D-dimer and TAT levels were associated with higher risk of all-cause mortality (range of hazard ratios were 1.66-1.17, p = 0.0001 and 1.46-1.04, p = 0.001 after adjusting for demographics and comorbid illnesses) and cardiovascular mortality (p = 0.009 and 0.003 in competing risk analyses). Conclusions: Elevations of TAT and D-dimer levels are common at hospital discharge in patients who appeared to have recovered clinically from pneumonia and are associated with higher risk of subsequent deaths, particularly due to cardiovascular disease. © 2011 Yende et al

Indoor Positioning with GNSS-Like Local Signal Transmitters

Not all the techniques proposed have, of course, been based on radio techniques, but they are the most important ones for two main reasons: their level of development and maturity on the one hand and their ability to "cross" or to "get around" obstacles such as walls, furniture or people on the other hand. Optical based techniques, like laser based distance measurements or vision based (camera) scene analysis systems present some real advantages in terms of measurement accuracy (a few millimetres for the former) or orientation determination (very useful for any guidance system, available for the latter). Unfortunately, the foreseen use of positioning devices being mainly dedicated to pedestrians in urban environments, optical obstacles are numerous. These latter techniques are then considered as potential hybridisation candidates. Many types of sensors have also been studied for positioning, such as infrared or ultrasound. Once again, although accuracy can reach centimetre values, the environmental constraints are not compatible with the ubiquitous systems being sought. Another category is, of course, inertial systems which could be a valuable alternative to radio systems: time and distance associated position drifts are not yet sufficiently mastered and the given positioning is relative , which means the need for "something else" in order to provide the user with an absolute location. The object of this section is to focus on radio based approaches