348 research outputs found

    Dissemination of patient blood management practices in Swiss intensive care units: a cross-sectional survey

    Full text link
    BACKGROUND Patient blood management (PBM) promotes the routine detection and treatment of anaemia before surgery, optimising the management of bleeding disorders, thus minimising iatrogenic blood loss and pre-empting allogeneic blood utilisation. PBM programmes have expanded from the elective surgical setting to nonsurgical patients, including those in intensive care units (ICUs), but their dissemination in a whole country is unknown. METHODS We performed a cross-sectional, anonymous survey (10 October 2018 to 13 March 2019) of all ordinary medical members of the Swiss Society of Intensive Care Medicine and the registered ICU nurses from the 77 certified adult Swiss ICUs. We analysed PBM-related interventions adopted in Swiss ICUs and related them to the spread of PBM in Swiss hospitals. We explored blood test ordering policies, blood-sparing strategies and red blood cell-related transfusion practices in ICUs. RESULTS A total of 115 medical doctors and 624 nurses (response rates 27% and 30%, respectively) completed the surveys. Hospitals had implemented a PBM programme according to 42% of physicians, more commonly in Switzerland's German-speaking regions (Odds Ratio [OR] 3.39, 95% confidence interval [CI] 1.23-9.35; p = 0.018) and in hospitals with more than 500 beds (OR 3.91, 95% CI 1.48-10.4; p = 0.006). The PBM programmes targeted the detection and correction of anaemia before surgery (79%), minimising perioperative blood loss (94%) and optimising anaemia tolerance (98%). Laboratory tests were ordered in 70.4% by the intensivist during morning rounds; the nurses performed arterial blood gas analyses autonomously in 48.4%. Blood-sparing techniques were used by only 42.1% of nurses (263 of 624, missing: 6) and 47.0% of physicians (54 of 115). Approximately 60% of respondents used an ICU-specific transfusion guideline. The reported haemoglobin threshold for the nonbleeding ICU population was 70 g/l and, therefore, was at the lower limit of current guidelines. CONCLUSIONS Based on this survey, the estimated proportion of the intensivists working in hospitals with a PBM initiative is 42%, with significant variability between regions and hospitals of various sizes. The risk of iatrogenic anaemia is relevant due to liberal blood sample collection practices and the underuse of blood-sparing techniques. The reported transfusion threshold suggests excellent adherence to current international ICU-specific transfusion guidelines

    Radiation damage of silicon strip detectors in the NA50 experiment

    Get PDF
    Abstract During operation of the multiplicity detector in the NA50 experiment the single sided AC-coupled p-on-n silicon strip detectors were exposed to charged particle fluences up to 10 14 eq n/cm 2 and ionising doses up to 20 Mrad, with a very non-uniform radiation spatial distribution. Radiation effects in the detectors observed during the '96 lead ion run as well as results of the post-run measurements are presented in this paper

    Analysis of radiation effects on silicon strip detectors in the NA50 experiment

    Get PDF
    Abstract During the operation of the Multiplicity Detector in the NA50 experiment the single sided AC-coupled p-on-n silicon strip detectors were exposed to charged particle fluences resulting in an equivalent 1 MeV neutron fluence up to 10 14 eq. n/cm 2 and a total ionising dose up to 20 Mrad, with a very non-uniform radiation spatial distribution. In this paper detailed analysis of radiation effects observed on the detectors during the 1996 lead ion run as well as results of measurements performed after the run are presented

    J/psi azimuthal anisotropy relative to the reaction plane in Pb-Pb collisions at 158 GeV per nucleon

    Get PDF
    The J/ψ\psi azimuthal distribution relative to the reaction plane has been measured by the NA50 experiment in Pb-Pb collisions at 158 GeV/nucleon. Various physical mechanisms related to charmonium dissociation in the medium created in the heavy ion collision are expected to introduce an anisotropy in the azimuthal distribution of the observed J/ψ\psi mesons at SPS energies. Hence, the measurement of J/ψ\psi elliptic anisotropy, quantified by the Fourier coefficient v2_2 of the J/ψ\psi azimuthal distribution relative to the reaction plane, is an important tool to constrain theoretical models aimed at explaining the anomalous J/ψ\psi suppression observed in Pb-Pb collisions. We present the measured J/ψ\psi yields in different bins of azimuthal angle relative to the reaction plane, as well as the resulting values of the Fourier coefficient v2_{2} as a function of the collision centrality and of the J/ψ\psi transverse momentum. The reaction plane has been estimated from the azimuthal distribution of the neutral transverse energy detected in an electromagnetic calorimeter. The analysis has been performed on a data sample of about 100 000 events, distributed in five centrality or pT_{\rm T} sub-samples. The extracted v2_{2} values are significantly larger than zero for non-central collisions and are seen to increase with pT_{\rm T}.Comment: proceedings of HP08 conference corrected a typo in one equatio

    The silicon multiplicity detector for the NA50 experiment at CERN

    Get PDF
    The design, operation and performance of the silicon strip Multiplicity Detector for the heavy-ion experiment NA50 at CERN are presented. The main features of the detector are high speed (50 MHz sampling frequency), high granularity (more than 13,000 strips), and good radiation resistance. The detector provided a measurement ofevent centrality in Pb–Pb collisions, as well as target identification and the measurement ofcharged particle pseudorapidity distributions as a function of centrality. r 2002 Elsevier Science B.V. All rights reserved. PACS: 29.4

    The silicon Multiplicity Detector for the NA50 experiment

    Get PDF
    Abstract The operation and performance of the silicon strip Multiplicity Detector in the heavy-ion experiment NA50 at CERN are presented together with a selection of physics results. The main features of the detector are high speed (50 MHz sampling frequency), high granularity (more than 13,000 strips), and good radiation resistance. The detector provided a measurement of event centrality in Pb–Pb collisions, as well as target identification and the measurement of charged particle pseudorapidity distributions as a function of centrality

    Bottomonium and Drell-Yan production in p-A collisions at 450 GeV

    Get PDF
    The NA50 Collaboration has measured heavy-quarkonium production in p-A collisions at 450 GeV incident energy (sqrt(s) = 29.1 GeV). We report here results on the production of the Upsilon states and of high-mass Drell-Yan muon pairs (m > 6 GeV). The cross-section at midrapidity and the A-dependence of the measured yields are determined and compared with the results of other fixed-target experiments and with the available theoretical estimates. Finally, we also address some issues concerning the transverse momentum distributions of the measured dimuons.Comment: 18 pages, 9 figures, to be published in Phys. Lett.

    A new measurement of J/psi suppression in Pb-Pb collisions at 158 GeV per nucleon

    Full text link
    We present a new measurement of J/psi production in Pb-Pb collisions at 158 GeV/nucleon, from the data sample collected in year 2000 by the NA50 Collaboration, under improved experimental conditions with respect to previous years. With the target system placed in vacuum, the setup was better adapted to study, in particular, the most peripheral nuclear collisions with unprecedented accuracy. The analysis of this data sample shows that the (J/psi)/Drell-Yan cross-sections ratio measured in the most peripheral Pb-Pb interactions is in good agreement with the nuclear absorption pattern extrapolated from the studies of proton-nucleus collisions. Furthermore, this new measurement confirms our previous observation that the (J/psi)/Drell-Yan cross-sections ratio departs from the normal nuclear absorption pattern for semi-central Pb-Pb collisions and that this ratio persistently decreases up to the most central collisions.Comment: 19 pages, 10 figures. Submitted to Eur. Phys. J.

    The dependence of the anomalous J/psi suppression on the number of participant nucleons

    Get PDF
    The observation of an anomalous J/psi suppression in Pb-Pb collisions by the NA50 Collaboration can be considered as the most striking indication for the deconfinement of quarks and gluons at SPS energies. In this Letter, we determine the J/psi suppression pattern as a function of the forward hadronic energy E-ZDC measured in a Zero Degree Calorimeter (ZDC). The direct connection between EZDC and the geometry of the collision allows us to calculate, within a Glauber approach, the precise relation between the number of participant nucleons N-part and E-ZDC. Then, we check if the experimental data can be better explained by a sudden or a smooth onset of the anomalous J/psi suppression as a function of the number of participants. (C) 2001 Elsevier Science B.V. All rights reserved.info:eu-repo/semantics/publishedVersio

    The primary cosmic ray composition between 10**15 and 10**16 eV from Extensive Air Showers electromagnetic and TeV muon data

    Full text link
    The cosmic ray primary composition in the energy range between 10**15 and 10**16 eV, i.e., around the "knee" of the primary spectrum, has been studied through the combined measurements of the EAS-TOP air shower array (2005 m a.s.l., 10**5 m**2 collecting area) and the MACRO underground detector (963 m a.s.l., 3100 m w.e. of minimum rock overburden, 920 m**2 effective area) at the National Gran Sasso Laboratories. The used observables are the air shower size (Ne) measured by EAS-TOP and the muon number (Nmu) recorded by MACRO. The two detectors are separated on average by 1200 m of rock, and located at a respective zenith angle of about 30 degrees. The energy threshold at the surface for muons reaching the MACRO depth is approximately 1.3 TeV. Such muons are produced in the early stages of the shower development and in a kinematic region quite different from the one relevant for the usual Nmu-Ne studies. The measurement leads to a primary composition becoming heavier at the knee of the primary spectrum, the knee itself resulting from the steepening of the spectrum of a primary light component (p, He). The result confirms the ones reported from the observation of the low energy muons at the surface (typically in the GeV energy range), showing that the conclusions do not depend on the production region kinematics. Thus, the hadronic interaction model used (CORSIKA/QGSJET) provides consistent composition results from data related to secondaries produced in a rapidity region exceeding the central one. Such an evolution of the composition in the knee region supports the "standard" galactic acceleration/propagation models that imply rigidity dependent breaks of the different components, and therefore breaks occurring at lower energies in the spectra of the light nuclei.Comment: Submitted to Astroparticle Physic
    corecore