Generation of a single pulmonary pressure-volume curve does not durably affect oxygenation in patients with acute respiratory distress syndrome

INTRODUCTION: It is possible that taking a static pressure-volume (PV) measurement could durably affect oxygenation and thus interfere with early evaluation of a therapeutic intervention delivered just after that measurement. The aim of the present study was to investigate the effects over time of a single static PV measurement on gas exchange and haemodynamics; the PV measurements were taken using a super syringe and by using the constant flow method in patients with acute respiratory distress syndrome. METHOD: We conducted a prospective, randomized and controlled interventional study in an intensive care unit. The study was conducted in 17 patients with early acute respiratory distress syndrome ventilated with a tidal volume of 6.9 ± 1.0 ml/kg, a plateau pressure of 27 ± 7 cmH(2)O and a positive end-expiratory pressure [PEEP] of 10 cmH(2)O. They were all evaluated for 1 hour after each of the following two measurements was taken and during a control period (in a randomized order): generation of a PV curve using a 2 l super syringe (PV(SS); insufflated volume = 1824 ± 381 ml, plateau pressure = 46 ± 9 cmH(2)O); and generation of a PV curve using the constant flow method on the ventilator (PV(CF); insufflated volume = 1120 ± 115 ml in zero end-expiratory pressure after 20 s expiratory pause, plateau pressure = 46 ± 11 cmH(2)O). The maximal airway pressure allowed during PV measurement was 60 cmH(2)O. PEEP was set to 10 cmH(2)O immediately after PV measurement. Partial arterial oxygen tension (Pao(2)), partial carbon dioxide tension (Paco(2)) and mean arterial pressure were recorded each minute. RESULTS: PV measurement did not significantly affect Pao(2), Paco(2), mean arterial pressure and lung mechanics. Two patients exhibited a sustained increase in Pao(2 )by more than 20% after PV(CF )(>60 minutes). Two patients exhibited a decrease in Pao(2 )by more than 20% after PV(SS), which was sustained in one. These latter patients had an upper inflection point identified on the PV curve. After PV(SS), Paco(2 )increased by more than 10 mmHg in two patients and returned to baseline values after 15 minutes. One patient exhibited a decrease in mean arterial pressure by more than 10 mmHg for less than 5 minutes after PV(SS )and one patient after PV(CF). CONCLUSION: Evaluation of the effects of a strategy aimed at improving oxygenation can be reliably recorded early after a single PV measurement that is not followed by a change in PEEP level. PV measurement using the constant flow method improves oxygenation in a limited number of patients

High levels of circulating leukocyte microparticles are associated with better outcome in acute respiratory distress syndrome

International audienceINTRODUCTION: The current study has addressed the presence and the cellular origin of microparticles (MP) isolated from bronchoalveolar lavage (BAL) fluid and from blood samples from patients with acute respiratory distress syndrome (ARDS). Their prognostic interest was also investigated. METHODS: Fifty-two patients were included within the first 24 hours of ARDS. They were compared to spontaneous breathing (SB) and ventilated control (VC) groups. Bronchoalveolar lavage (BAL) and blood samples were obtained on Day 1 and Day 3 in an ARDS group. Leukocyte microparticles (LeuMP), neutrophil microparticles (NeuMP), endothelial microparticles (EMP), and platelet microparticles (PMP) were measured in arterial blood and in BAL samples by flow cytometry. Mortality from all causes was recorded at Day 28. RESULTS: All MP subpopulations were detected in BAL. However, only LeuMP and NeuMP were elevated in ARDS patients compared to the SB group (P = 0.002 for both). Among ARDS patients, higher levels of LeuMP were detected in blood (Day 1) and in BAL (Day 3) in survivors as compared with the non survivors. Circulating LeuMP >60 elements/microliter detectable on Day 1 of ARDS, was associated with a higher survival rate (odds ratio, 5.26; 95% confidence interval, 1.10 to 24.99; P = 0.037). CONCLUSIONS: The identification of the cellular origin of microparticles at the onset of ARDS has identified LeuMP as a biomarker of prognostic significance. The higher levels of LeuMP in survivors could be associated with a protective role of this MP subpopulation. This hypothesis needs further investigations

The Role of Natural Killer Cells in Sepsis

Severe sepsis and septic shock are still deadly conditions urging to develop novel therapies. A better understanding of the complex modifications of the immune system of septic patients is needed for the development of innovative immunointerventions. Natural killer (NK) cells are characterized as CD3−NKp46+CD56+ cells that can be cytotoxic and/or produce high amounts of cytokines such as IFN-γ. NK cells are also engaged in crosstalks with other immune cells, such as dendritic cells, macrophages, and neutrophils. During the early stage of septic shock, NK cells may play a key role in the promotion of the systemic inflammation, as suggested in mice models. Alternatively, at a later stage, NK cells-acquired dysfunction could favor nosocomial infections and mortality. Standardized biological tools defining patients' NK cell status during the different stages of sepsis are mandatory to guide potential immuno-interventions. Herein, we review the potential role of NK cells during severe sepsis and septic shock

Repertoire of Intensive Care Unit Pneumonia Microbiota

Despite the considerable number of studies reported to date, the causative agents of pneumonia are not completely identified. We comprehensively applied modern and traditional laboratory diagnostic techniques to identify microbiota in patients who were admitted to or developed pneumonia in intensive care units (ICUs). During a three-year period, we tested the bronchoalveolar lavage (BAL) of patients with ventilator-associated pneumonia, community-acquired pneumonia, non-ventilator ICU pneumonia and aspiration pneumonia, and compared the results with those from patients without pneumonia (controls). Samples were tested by amplification of 16S rDNA, 18S rDNA genes followed by cloning and sequencing and by PCR to target specific pathogens. We also included culture, amoeba co-culture, detection of antibodies to selected agents and urinary antigen tests. Based on molecular testing, we identified a wide repertoire of 160 bacterial species of which 73 have not been previously reported in pneumonia. Moreover, we found 37 putative new bacterial phylotypes with a 16S rDNA gene divergence ≥98% from known phylotypes. We also identified 24 fungal species of which 6 have not been previously reported in pneumonia and 7 viruses. Patients can present up to 16 different microorganisms in a single BAL (mean ± SD; 3.77±2.93). Some pathogens considered to be typical for ICU pneumonia such as Pseudomonas aeruginosa and Streptococcus species can be detected as commonly in controls as in pneumonia patients which strikingly highlights the existence of a core pulmonary microbiota. Differences in the microbiota of different forms of pneumonia were documented

Spectres infrarouges et attributions des vibrations fondamentales de la cyclohexanone et des chloro=2 et bromo=2=cyclohexanones

Les spectres infrarouges et Raman de la cyclohexanone ont été interprétés en les comparant à ceux du cyclohexane.Les spectres infrarouges des chloro-2 et bromo-2-cyclohexanones ont été enregistrés en solution diluée dans un solvant inerte, à l’état liquide pur et à l’état solide à — 180 °C et leur comparaison a permis de séparer les bandes d’absorption provenant des isomères axial et équatorial. Une attribution des vibrations normales a en outre été faite par analogie avec la cyclohexanone

Implications du procollagène III et du facteur de croissance et de transformation [bêta]1 dans le pronostic du syndrome de détresse respiratoire aiguë

Objectif : déterminer les cinétiques alvéolaires et systémiques du transforming growth factor 1 (TGFb1) et du procollagène III (PCP III) au cours du SDRA. Etude: prospective observationnelle réalisée dans trois réanimations. Sujets :56 patients en SDRA de moins de 48 heures ont été inclus consécutivement. Mesures : dosages systémiques et alvéolaires de PCP III et de TGFb1 au 1er 3ème 7ème et 14ème jour du SDRA. Résultats: la mortalité au 28ème jour était de 35.7%. Les taux de PCP III sériques et alvéolaires étaient plus élevées dans le groupe non survivant que dans le groupe survivant à J28. En analyse multivariée l'Odds ratio (OR) à l'inclusion du PCP III sérique >8.94 g/L est de 4.82 IC 95%[1.16-20.01] et augmente au 3ème jour (OR à 33.22, IC 95%[2.33-473.13]). Le TGFb1 n'est pas associé à la mortalité au cours du SDRA. Conclusion : Des concentrations élevées de PCP III alvéolaire et systémique sont associées à une augmentation du risque de décès chez les patients en SDRA.AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

MARQUEURS DE L'INFLAMMATION ET DIAGNOSTIC PRECOCE DES COMPLICATIONS INFECTIEUSES POSTOPERATOIRES (DES ANESTHESIE-REANIMATION)

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Epidémiologie des pneumopathies acquises sous ventilation mécanique au cours du SDRA

AIX-MARSEILLE2-BU Méd/Odontol. (130552103) / SudocSudocFranceF