556 research outputs found

    The outcome of extubation failure in a community hospital intensive care unit: a cohort study

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    INTRODUCTION: Extubation failure has been associated with poor intensive care unit (ICU) and hospital outcomes in tertiary care medical centers. Given the large proportion of critical care delivered in the community setting, our purpose was to determine the impact of extubation failure on patient outcomes in a community hospital ICU. METHODS: A retrospective cohort study was performed using data gathered in a 16-bed medical/surgical ICU in a community hospital. During 30 months, all patients with acute respiratory failure admitted to the ICU were included in the source population if they were mechanically ventilated by endotracheal tube for more than 12 hours. Extubation failure was defined as reinstitution of mechanical ventilation within 72 hours (n = 60), and the control cohort included patients who were successfully extubated at 72 hours (n = 93). RESULTS: The primary outcome was total ICU length of stay after the initial extubation. Secondary outcomes were total hospital length of stay after the initial extubation, ICU mortality, hospital mortality, and total hospital cost. Patient groups were similar in terms of age, sex, and severity of illness, as assessed using admission Acute Physiology and Chronic Health Evaluation II score (P > 0.05). Both ICU (1.0 versus 10 days; P < 0.01) and hospital length of stay (6.0 versus 17 days; P < 0.01) after initial extubation were significantly longer in reintubated patients. ICU mortality was significantly higher in patients who failed extubation (odds ratio = 12.2, 95% confidence interval [CI] = 1.5–101; P < 0.05), but there was no significant difference in hospital mortality (odds ratio = 2.1, 95% CI = 0.8–5.4; P < 0.15). Total hospital costs (estimated from direct and indirect charges) were significantly increased by a mean of US33,926(9533,926 (95% CI = US22,573–45,280; P < 0.01). CONCLUSION: Extubation failure in a community hospital is univariately associated with prolonged inpatient care and significantly increased cost. Corroborating data from tertiary care centers, these adverse outcomes highlight the importance of accurate predictors of extubation outcome

    Degradation of a quantum directional reference frame as a random walk

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    We investigate if the degradation of a quantum directional reference frame through repeated use can be modeled as a classical direction undergoing a random walk on a sphere. We demonstrate that the behaviour of the fidelity for a degrading quantum directional reference frame, defined as the average probability of correctly determining the orientation of a test system, can be fit precisely using such a model. Physically, the mechanism for the random walk is the uncontrollable back-action on the reference frame due to its use in a measurement of the direction of another system. However, we find that the magnitude of the step size of this random walk is not given by our classical model and must be determined from the full quantum description.Comment: 5 pages, no figures. Comments are welcome. v2: several changes to clarify the key results. v3: journal reference added, acknowledgements and references update

    European Green Crab Mitigation in Whatcom County

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    This report presents a background on the invasive European green crab ( Carcinus maenas ), describes a variety of techniques to monitor and manage their presence in the region, and puts forth several comprehensive strategies for mitigating a potential invasion of C. maenas in the Salish Sea. C. maenas was likely initially introduced to the Pacific coast of the United States as larvae carried in ballast water, though they are also spread as larval by currents and as hitchhikers in seafood transport. C. maenas tolerates a wide range of salinities, temperatures, and habitats, they prey on virtually any available species, and they are aggressively competitive. They are capable of reproducing multiple times in a year and their larvae can be carried long distances by currents. These among other factors make C. maenas adept at establishing themselves in new regions, and once established they can have extreme impacts on the ecosystem. C. maenas poses a threat to biodiversity as they outcompete and prey upon local species, but knowledge of their life history and their interactions with the environment can be used to design and enhance management plans, to increase their efficiency and specificity. Traps can be designed and baited to catch C. maenas with higher selectivity. Larval behavior can be integrated with tidal and current data to predict where invasions are likely and determine which sites should be monitored for early detection. Citizens can be educated in identification of C. maenas and participate in beach surveys and early detection efforts. With the information and proposed strategies outlined in this project, mitigation of the potential impacts of a C. maenas invasion in Whatcom County waters will be more surmountable

    Infrared Observations of the Candidate LBV 1806-20 & Nearby Cluster Stars

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    We report near-infrared photometry, spectroscopy, and speckle imaging of the hot, luminous star we identify as candidate LBV 1806-20. We also present photometry and spectroscopy of 3 nearby stars, which are members of the same star cluster containing LBV 1806-20 and SGR 1806-20. The spectroscopy and photometry show that LBV 1806-20 is similar in many respects to the luminous ``Pistol Star'', albeit with some important differences. They also provide estimates of the effective temperature and reddening of LBV 1806-20, and confirm distance estimates, leading to a best estimate for the luminosity of this star of >5×106L> 5 \times 10^6 L_{\odot}. The nearby cluster stars have spectral types and inferred absolute magnitudes which confirm the distance (and thus luminosity) estimate for LBV 1806-20. If we drop kinematic measurements of the distance (15.11.3+1.815.1 ^{+1.8}_{-1.3} kpc), we have a lower limit on the distance of >9.5>9.5 kpc, and on the luminosity of >2×106L>2 \times 10^6 L_{\odot}, based on the cluster stars. If we drop both the kinematic and cluster star indicators for distance, an ammonia absorption feature sets yet another lower limit to the distance of >5.7>5.7 kpc, with a corresponding luminosity estimate of >7×105L>7 \times 10^5 L_{\odot} for the candidate LBV 1806-20. Furthermore, based on very high angular-resolution speckle images, we determine that LBV 1806-20 is not a cluster of stars, but is rather a single star or binary system. Simple arguments based on the Eddington luminosity lead to an estimate of the total mass of LBV 1806-20 (single or binary) exceeding 190M190 M_{\odot}. We discuss the possible uncertainties in these results, and their implications for the star formation history of this cluster.Comment: 36 pages, including 8 figures (Figures 1 and 7 in JPG format due to space); Accepted for publication in Ap

    Multipartite entangled coherent states

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    We propose a scheme for generating multipartite entangled coherent states via entanglement swapping, with an example of a physical realization in ion traps. Bipartite entanglement of these multipartite states is quantified by the concurrence. We also use the NN--tangle to compute multipartite entanglement for certain systems. Finally we establish that these results for entanglement can be applied to more general multipartite entangled nonorthogonal states.Comment: 7 pages, two figures. We added more detail discussions on the generation of multipartite entangled coherent states and multipartite entangelemen

    A Randomized Trial of Nighttime Physician Staffing in an Intensive Care Unit

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    Background Increasing numbers of intensive care units (ICUs) are adopting the practice of nighttime intensivist staffing despite the lack of experimental evidence of its effectiveness. Methods We conducted a 1-year randomized trial in an academic medical ICU of the effects of nighttime staffing with in-hospital intensivists (intervention) as compared with nighttime coverage by daytime intensivists who were available for consultation by telephone (control). We randomly assigned blocks of 7 consecutive nights to the intervention or the control strategy. The primary outcome was patients’ length of stay in the ICU. Secondary outcomes were patients’ length of stay in the hospital, ICU and in-hospital mortality, discharge disposition, and rates of readmission to the ICU. For length-of-stay outcomes, we performed time-to-event analyses, with data censored at the time of a patient’s death or transfer to another ICU. Results A total of 1598 patients were included in the analyses. The median Acute Physiology and Chronic Health Evaluation (APACHE) III score (in which scores range from 0 to 299, with higher scores indicating more severe illness) was 67 (interquartile range, 47 to 91), the median length of stay in the ICU was 52.7 hours (interquartile range, 29.0 to 113.4), and mortality in the ICU was 18%. Patients who were admitted on intervention days were exposed to nighttime intensivists on more nights than were patients admitted on control days (median, 100% of nights [interquartile range, 67 to 100] vs. median, 0% [interquartile range, 0 to 33]; P\u3c0.001). Nonetheless, intensivist staffing on the night of admission did not have a significant effect on the length of stay in the ICU (rate ratio for the time to ICU discharge, 0.98; 95% confidence interval [CI], 0.88 to 1.09; P=0.72), ICU mortality (relative risk, 1.07; 95% CI, 0.90 to 1.28), or any other end point. Analyses restricted to patients who were admitted at night showed similar results, as did sensitivity analyses that used different definitions of exposure and outcome. Conclusions In an academic medical ICU in the United States, nighttime in-hospital intensivist staffing did not improve patient outcomes. (Funded by University of Pennsylvania Health System and others; ClinicalTrials.gov number, NCT01434823.

    Private Sector Union Density and the Wage Premium: Past, Present, and Future

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    The rise and decline of private sector unionization were among the more important features of the U.S. labor market during the twentieth century. Following a dramatic spurt in unionization after passage of the depression-era National Labor Relations Act (NLRA) of 1935, union density peaked in the mid-1950s, and then began a continuous decline. At the end of the century, the percentage of private wage and salary workers who were union members was less than 10 percent, not greatly different from union density prior to the NLRA

    Obesity and the Rate of Time Preference: Is there a Connection?

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    We hypothesize that recent trends in U.S. and worldwide obesity are, in part, related to an increase in the marginal rate of time preference, where time preference refers to the rate at which people are willing to trade current benefit for future benefit. The higher the rate of time preference, the larger is the factor by which individuals discount the future health risks associated with current consumption. Data from the United States, as well as international evidence, suggests that a relationship between these two variables is plausible. We encourage researchers to explore the possible link between obesity and time preference, as important insights are likely to result
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