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Dive into the research topics where Hervé Hyvernat is active.

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Featured researches published by Hervé Hyvernat.


Critical Care | 2012

Transthoracic Echocardiography with Doppler Tissue Imaging predicts weaning failure from mechanical ventilation: evolution of the left ventricle relaxation rate during a spontaneous breathing trial is the key factor in weaning outcome.

Sébastien Moschietto; Denis Doyen; Ludovic Grech; Jean Dellamonica; Hervé Hyvernat; Gilles Bernardin

IntroductionThere is growing evidence to suggest that transthoracic echocardiography (TTE) should be used to identify the cardiac origin of respiratory weaning failure. The aims of our study were: first, to evaluate the ability of transthoracic echocardiography, with mitral Doppler inflow E velocity to annular tissue Doppler Ea wave velocity (E/Ea) ratio measurement, to predict weaning failure from mechanical ventilation in patients, including those with atrial fibrillation; and second, to determine whether the depressed left ejection fraction and/or diastolic dysfunction participate in weaning outcome.MethodsThe sample included patients on mechanical ventilation for over 48 hours. A complete echocardiography was performed just before the spontaneous breathing trial (SBT) and 10 minutes after starting the SBT. Systolic dysfunction was defined by a left ventricle ejection fraction under 50% and relaxation impairment by a protodiastolic annulus mitral velocity Ea under or equal to 8 cm/second.ResultsA total of 68 patients were included. Twenty failed the weaning process and the other 48 patients succeeded. Before the SBT, the E/Ea ratio was higher in the failed group than in the successful group. The E/Ea measured during the SBT was also higher in the failed group. The cut-off value, obtained from receiver operating characteristics (ROC) curve analysis, to predict weaning failure gave an E/Ea ratio during the SBT of 14.5 with a sensitivity of 75% and a specificity of 95.8%. The left ventricular ejection fraction did not differ between the two groups whereas Ea was lower in the failed group. Ea increased during SBT in the successful group while no change occurred in the failed group.ConclusionsMeasurement of the E/Ea ratio with TTE could predict weaning failure. Diastolic dysfunction with relaxation impairment is strongly associated with weaning failure. Moreover, the impossibility of enhancing the left ventricle relaxation rate during the SBT seems to be the key factor of weaning failure. In contrast, the systolic dysfunction was not associated with weaning outcome.


Journal of Critical Care | 2012

The early phase of human sepsis is characterized by a combination of apoptosis and proliferation of T cells

Pierre Roger; Hervé Hyvernat; Michel Ticchioni; Gaurav Kumar; Jean Dellamonica; Gilles Bernardin

PURPOSE T cell activation as well as unresponsiveness has been described in separate studies in sepsis. Our aim was to establish the coexistence of both T cell fate in human sepsis. PATIENTS AND METHODS This is a cross-sectional study of 48 patients presenting with severe sepsis or septic shock and 15 healthy controls. Cytofluorometric techniques were used to quantify T cell activation, apoptosis, proliferation, expression of costimulatory molecules, and cytokine secretion. RESULTS Patients with sepsis were characterized by a significant increase in the percentage of activated T cell subsets, as measured using CD69 marker, compared with healthy controls (P<.05). T cell proliferation as measured through Ki67 expression was obvious in infected patients for both CD4 and CD8 T cell subsets compared with controls (P ≤.006). T cell subset apoptosis as measured using Hoechst dye was also increased in infected patients compared with controls (P ≤.002). CD4 T cell proliferation was correlated with interleukin 2 secretion (R(2)=0.84, P<.001), whereas up-regulation of CD4 T cell apoptosis was correlated with CTLA-4 expression (R(2)=0.24, P=.001). No such similar relationship was observed for CD8(+) T cells. CONCLUSIONS Concomitant T cell proliferation and T cell apoptosis are observed in human sepsis, being related to a different pathway.


Medecine Et Maladies Infectieuses | 2011

Impact of an assisted reassessment of antibiotic therapies on the quality of prescriptions in an intensive care unit

L. Bornard; J. Dellamonica; Hervé Hyvernat; Fernand Girard-Pipau; N. Molinari; Albert Sotto; P.-M. Roger; Gilles Bernardin; C. Pulcini

OBJECTIVES The studys objective was to assess the impact of a professional multifaceted intervention designed to improve the quality of inpatient empirical therapeutic antibiotic courses at the time of their reassessment, i.e. 24 to 96 hours after treatment initiation. DESIGN We conducted a 5-month prospective pre- and post-intervention study in a medical Intensive Care Unit (ICU) in a teaching hospital, using time-series analysis. The intervention was a multifaceted professional intervention combining systematic 3-weekly visits of an infectious diseases specialist to discuss all antibiotic therapies, interactive teaching courses, and daily contact with a microbiologist. RESULTS Eighty-one antibiotic prescriptions were assessed, 37 before and 44 after the intervention. The prevalence of adequate antibiotic prescriptions was high and not statistically different before and after the intervention (73% vs. 80%, P=0.31), both for sudden change (P=0.67) and linear trend (P=0.055), using interrupted time-series analysis. The intervention triggered a more frequent reassessment of the diagnosis between day 2 and day 4 (11% vs. 32%, P=0.02) and slightly improved the adaptation of antibiotic therapies to positive microbiology (25% before vs. 50% after, P=0.18). CONCLUSIONS Our multifaceted intervention may have improved the quality of antibiotic therapies around day 3 of prescription, but the difference did not reach statistical significance, possibly because of a ceiling effect.


Scandinavian Journal of Infectious Diseases | 2007

Fatal Staphylococcus aureus haemorrhagic pneumonia producing Panton-Valentine leucocidin

Hervé Hyvernat; Céline Pulcini; Danielle Carles; Adrien Roques; Philippe Lucas; Véronique Hofman; Paul Hofman; Gilles Bernardin

We present 2 cases of community acquired S. aureus pneumonia carrying Panton Valentine leucocidin (PVL). These cases illustrate this clinical entity characterized by a younger and healthier population than usual staphylococcal pneumonias and complicated by a 75% mortality rate. We also discuss the diagnosis and therapeutic difficulties.


Scandinavian Journal of Infectious Diseases | 2006

Native-valve infective endocarditis caused by Enterobacteriaceae: report on 9 cases and literature review.

Cecile Aubron; Julien Charpentier; Jean-Louis Trouillet; Georges Offenstadt; Alain Mercat; Gilles Bernardin; Hervé Hyvernat; Michel Wolff

Although the demographic characteristics of patients who develop infective endocarditis (IE) have changed over the last few decades, Enterobacteriaceae remain rarely responsible. We report the clinical and epidemiological characteristics of 9 patients with native-valve Enterobacteriaceae IE from 6 French medical intensive care units over a 10-y period and have identified 29 additional cases in the literature. Nearly a third of the 38 patients were immunocompromized and/or had previously known valvular heart disease. Salmonella spp. and Yersinia spp. were the most frequently isolated microorganisms reported in the literature. The overall mortality rate was 24% (9/38) and was lower for operated patients (10% (1/10)) compared to those who did not undergo valve surgery (31% (8/26)). Our results confirmed the rarity of native-valve endocarditis caused by Enterobacteriaceae, pathogens frequently responsible for nosocomial and community-acquired bacteraemias. This paradox may be explained by susceptibility to the bactericidal action of serum and the inability of these bacteria to colonize the endocardium.


Revue de Médecine Interne | 2003

Syndrome de Lemierre : à propos de 6 cas

Céline Pulcini; F. Vandenbos; S. Roth; V. Mondain-Miton; E. Bernard; P.-M. Roger; F. De Salvador-Guillouet; Hervé Hyvernat; Fernand Girard-Pipau; M. Mattei; Pierre Dellamonica

Resume Propos. – Le syndrome de Lemierre est une pathologie rare mais grave qui associe fievre, douleur cervicale et symptomatologie pulmonaire dans les suites d’une infection oropharyngee, le plus souvent une angine. La large utilisation des antibiotiques dans les infections oropharyngees n’a pas permis une disparition de cette infection. Nous avons voulu, a travers ces 6 observations originales faire partager notre experience. Methodes. – Il s’agit d’une etude descriptive retrospective menee entre 1995 et 2000 dans deux services (maladies infectieuses et tropicales et reanimation medicale) du centre hospitalier universitaire de Nice. Resultats. – Nous presentons une serie de 6 cas de ce syndrome, tous de sexe feminin et âges de 27 ans en moyenne. Il s’agissait de sujets anterieurement sains et la symptomatologie oropharyngee initiale etait une angine. Ces patientes presentaient dans la majorite des cas des signes de sepsis severe et une patiente est decedee des suites d’un choc septique. Dans les autres cas, l’evolution a ete favorable sous traitement. Le delai entre l’angine et l’apparition du syndrome infectieux etait de 7 jours en moyenne. Le traitement a consiste en une association betalactamine et metronidazole dans 4 cas, amoxicilline–acide clavulanique pour les autres cas. Une anticoagulation a ete systematiquement debutee en cas de thrombose jugulaire interne documentee. Conclusions. – Le diagnostic peut etre fortement suspecte sur la clinique et confirme secondairement par les examens complementaires. Le pronostic depend etroitement de la rapidite et de la qualite de la prise en charge. Nous avons donc souhaite familiariser nos confreres avec cette pathologie en rapportant notre experience personnelle.


Heart & Lung | 2014

Tako-Tsubo cardiomyopathy presenting with cardiogenic shock successfully treated with milrinone: A case report

Denis Doyen; Jean Dellamonica; Pamela Moceri; Sébastien Moschietto; Hervé Hyvernat; Emile Ferrari; Gilles Bernardin

We report the case of a middle age patient presenting with Tako-Tsubo cardiomyopathy (TTC) complicated by cardiogenic shock that was successfully handled with milrinone. A 64-year old man presented with cardiogenic shock after benzodiazepine and alcohol intoxication. A slight elevation of troponin and typical left ventricular ballooning without coronary lesions suggested TTC. Within a few hours milrinone infusion normalized the cardiac index. TTC is responsible for severe transient left ventricular dysfunction occurring after physical or psychological stress. The major pathophysiological mechanism involved is disproportionate catecholamine secretion, which may stun the myocardium. We considered if treatment of this unique physiopathology with catecholamines could be dangerous in these patients and if alternative inotropes such as milrinone should be preferred.


Journal of Infection | 2015

High negative predictive value diagnostic strategies for the reevaluation of early antifungal treatment: A multicenter prospective trial in patients at risk for invasive fungal infections

Lilia Hasseine; Sophie Cassaing; Florence Robert-Gangneux; Judith Fillaux; Pierre Marty; Jean-Pierre Gangneux; V. Mondain; Hervé Hyvernat; Eric Rosenthal; Olivier Cointault; Laurence Lavayssière; Bernard Georges; Antoine Berry; Sophie de Guibert; Stanislas Nimubona; Matthieu Revest; Pierre Tattevin

Early antifungal therapeutic strategies are proposed during invasive fungal infection (IFI), but antifungal stewardship programs should institute a systematic reevaluation of prescriptions, particularly in the context of empirical treatment. Here, we aimed to evaluate the performances and particularly the negative predictive value (NPV) of diagnostic strategies, including a whole blood panfungal quantitative PCR assay (PF-qPCR) in a high risk population for IFI. The first step was to standardize and optimize a new PF-qPCR targeting ITS2 region. Then, this method was evaluated in a multicenter prospective study including 313 patients with suspected IFI for whom an early antifungal treatment was prescribed. All patients enrolled at day 0 of their treatment benefited from serum Aspergillus galactomannan (GM) antigen detection twice a week, weekly PF-qPCR assay, and when indicated and feasible, CT-scan and mycological sampling. In total, 125 of 313 patients were diagnosed with IFI: 68 invasive aspergillosis (eight proven, 48 probable and 12 possible), one fusariosis, 47 candidemia, three disseminated candidiasis and six cryptococcosis. Globally, the sensitivity of the PF-qPCR assay was only 40%, but the specificity, PPV and NPV were 96%, 88% and 69%, respectively. In the population of patients at high risk for invasive aspergillosis who also benefited from Aspergillus GM detection, the sensitivity and the NPV of the combined detection reached to 78% and 84%, respectively. Even higher NPV were obtained when combining negative PF-qPCR and CT scan (95%) as well as negative GM and CT scan (93%), thus allowing to rationalize and re-evaluate the prescription of empirical treatment in such highly selected population.


PLOS ONE | 2017

Association of serum lactate with outcome after out-of-hospital cardiac arrest treated with therapeutic hypothermia

Jean-Christophe Orban; Michaël Novain; Florian Cattet; Rémi Plattier; Mohamed Nefzaoui; Hervé Hyvernat; Olivier Raguin; Michel Kaidomar; Sébastien Kerever; Carole Ichai

Aims Lactate reflects hypoxic insult in many conditions and is considered as a prognosis factor. But, after cardiac arrest, its interest is still debated. Our study aimed to assess the prognosis value of lactate in out-of-hospital cardiac arrest patients treated with therapeutic hypothermia. Methods This retrospective observational study included out-of-hospital cardiac arrest patients treated with therapeutic hypothermia in four ICUs. Lactate levels were compared at different times during the first 24 hours according to outcome at ICU discharge and to the type of death (multiorgan or neurologic failure). Results Two hundred and seventy-two patients were included, 89 good outcome and 183 poor outcome. In the latter group, 171 patients died, from multiorgan failure in 30% and neurologic failure in 70%. Lactate levels were higher in the poor compared to the good outcome patients at admission (5.4 (3.3–9.4) vs. 2.2 (1.5–3.6) mmol/L; p<0.01), 12 hours (2.5 (1.6–4.7) vs. 1.4 (1.0–2.2) mmol/L; p<0.01) and 24 hours (1.8 (1.1–2.8) vs. 1.3 (0.9–2.1) mmol/L; p<0.01). Patients succumbing from multiorgan failure exhibited higher lactate levels compared to those dying from neurologic failure at admission (7.9 (3.9–12.0) vs. 5.2 (3.3–8.8) mmol/L; p<0.01), H12 (4.9 (2.1–8.9) vs. 2.2 (1.4–3.4) mmol/L; p<0.01) and H24 (3.3 (1.8–5.5) vs. 1.4 (1.1–2.5) mmol/L; p<0.01). Initial lactate levels showed an increasing proportion of poor outcome from the first to fourth quartile. Conclusions After out-of-hospital cardiac arrest treated with therapeutic hypothermia, lactate levels during the first 24 hours seem linked with ICU outcome. Patients dying from multiorgan failure exhibit higher initial lactate concentrations than patients succumbing from neurological failure.


Medical Mycology | 2010

Fatal peritonitis caused by Rhizopus microsporus

Hervé Hyvernat; Brigitte Dunais; Fanny Burel-Vandenbos; Sarah Guidicelli; Gilles Bernardin; Martine Gari-Toussaint

A 52-year-old woman with a history of Crohns disease was admitted due to peritonitis which followed an intestinal perforation. After transitory treatment with voriconazole, resolution of the infection was complicated by recurring peritonitis resulting from necrosis and perforation of the left colon which ultimately lead to the death of the patient. Microscopic examination of the peritoneal fluid revealed the presence of broad, irregular hyphae and culture of the fluid yielded Rhizopus microsporus. The identification of the fungus was confirmed by its characteristic microscopic morphology and sequencing of the ITS region of the rDNA. The histopathologic examination of the colon tissue demonstrated the presence of broad, non-septate hyphae and the same fungus was again isolated in culture.

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Gilles Bernardin

University of Nice Sophia Antipolis

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Denis Doyen

University of Nice Sophia Antipolis

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Céline Pulcini

University of Nice Sophia Antipolis

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Fanny Burel-Vandenbos

University of Nice Sophia Antipolis

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P.-M. Roger

University of Nice Sophia Antipolis

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Fernand Girard-Pipau

University of Nice Sophia Antipolis

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Jean-Christophe Orban

University of Nice Sophia Antipolis

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Pierre Dellamonica

University of Nice Sophia Antipolis

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