16 research outputs found

    Costes de las inoculaciones accidentales en personal sanitario de un hospital

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    ResumenObjetivosEl objetivo de este estudio es calcular el coste medio a que asciende cada seguimiento de hepatitis B, C y VIH en el personal sanitario que ha sufrido una inoculación accidental, desagregar el coste en dependencia del estado serológico de la fuente e identificar los apartados que influyen en mayor grado en la cuantía de este resultado.MétodosSe realizó una descripción de costes. El programa post-exposición se modelizó en un árbol de decisión que combinaba probabilidades (porcentaje de cada tipo de fuente en función de su positividad a los tres virus e inmunización del accidentado frente a hepatitis B) y costes monetarios (pesetas del año 1994). Estos costes fueron: personal, laboratorio, farmacia, energéticos, limpieza, teléfono, material médico y de oficina, amortización y pérdidas productivas. Se realizó un análisis de sensibilidad en función del cumplimiento real del programa.ResultadosEl coste medio de cada inoculación fue de 39.564 ptas. (29.750 ptas. aplicando el análisis de sensibilidad), con un rango desde las 86.864 ptas. (fuente positiva a los tres virus y accidentado no inmunizado) a las 23.074 ptas. (fuente negativa a los tres virus). Si la fuente era hepatitis B positiva, el coste medio fue de 86.093 ptas. cuando el accidentado no estaba inmunizado y de 53.232 si lo estaba. La mayor parte del coste residió en las pruebas serológicas (rango del 72,8% al 87,7%).ConclusionesEl alto coste sugiere una evaluación adecuada del riesgo con el fin de evitar seguimientos innecesarios. El modelo utilizado permite conocer el coste de cada episodio potencialmente evitable y puede aplicarse en cualquier hospital con el objetivo de evaluar económicamente nuevos dispositivos preventivos.SummaryObjectivesThe aim of this study was to calculate the average cost of each hepatitis B, C and HIV follow-up carried out in the health personnel that have suffered an exposure to blood and body fluids and to estimate the cost for each of the different types of sources as wall as to identify the items that account for the main part of the cost.MethodsA cost analysis was carried out. The post-exposure programme was modelled in a decision tree combining probabilities (percentage of each type of source in dependence of its positivity for the three viruses and immunization state of the health personnel against hepatitis B) and monetary costs (pesetas from 1994). Costs included: salaries, laboratory, chemist, energy, cleaning, telephone, medical and office equipment, amortization and lost productivity. A sensitivity analysis was carried out with the real fulfillment of the programme.ResultsThe average cost was 39,564 ptas. (29,750 ptas. applying the sensitivity analysis), with a range from 86,864 ptas. (source positive for the three viruses and injured subject not immunized) to 23,074 ptas. (source negative for the three viruses). If the source was hepatitis B positive, the average cost was 86,093 ptas. when the injured subject was not immunized and 53,232 ptas. if he was immunized. Serologic tests account for the main part of the cost (range from 72.8% to 87.7%).ConclusionsHigh cost suggests an appropiate risk evaluation in order to avoid unnecessary follow-ups. The model used allows to know the cost of each potentially avoided episode and it could be used for any hospital in order to make an economical evaluation of new preventive devices

    Radio frequency and DC high voltage breakdown of high pressure helium, argon, and xenon

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    Motivated by the possibility of guiding daughter ions from double beta decay events to single-ion sensors for barium tagging, the NEXT collaboration is developing a program of R&D to test radio frequency (RF) carpets for ion transport in high pressure xenon gas. This would require carpet functionality in regimes at higher pressures than have been previously reported, implying correspondingly larger electrode voltages than in existing systems. This mode of operation appears plausible for contemporary RF-carpet geometries due to the higher predicted breakdown strength of high pressure xenon relative to low pressure helium, the working medium in most existing RF carpet devices. In this paper we present the first measurements of the high voltage dielectric strength of xenon gas at high pressure and at the relevant RF frequencies for ion transport (in the 10 MHz range), as well as new DC and RF measurements of the dielectric strengths of high pressure argon and helium gases at small gap sizes. We find breakdown voltages that are compatible with stable RF carpet operation given the gas, pressure, voltage, materials and geometry of interest

    Radio Frequency and DC High Voltage Breakdown of High Pressure Helium, Argon, and Xenon

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    [EN] Motivated by the possibility of guiding daughter ions from double beta decay events to single-ion sensors for barium tagging, the NEXT collaboration is developing a program of R&D to test radio frequency (RF) carpets for ion transport in high pressure xenon gas. This would require carpet functionality in regimes at higher pressures than have been previously reported, implying correspondingly larger electrode voltages than in existing systems. This mode of operation appears plausible for contemporary RF-carpet geometries due to the higher predicted breakdown strength of high pressure xenon relative to low pressure helium, the working medium in most existing RF carpet devices. In this paper we present the first measurements of the high voltage dielectric strength of xenon gas at high pressure and at the relevant RF frequencies for ion transport (in the 10MHz range), as well as new DC and RF measurements of the dielectric strengths of high pressure argon and helium gases at small gap sizes. We find breakdown voltages that are compatible with stable RF carpet operation given the gas, pressure, voltage, materials and geometry of interest.Woodruff, K.; Baeza-Rubio, J.; Huerta, D.; Jones, BJP.; Mcdonald, AD.; Norman, L.; Nygren, DR.... (2020). Radio Frequency and DC High Voltage Breakdown of High Pressure Helium, Argon, and Xenon. Journal of Instrumentation. 15(4):1-15. https://doi.org/10.1088/1748-0221/15/04/P04022S115154Dehmelt, H. G., & Major, F. G. (1962). Orientation of(He4)+Ions by Exchange Collisions with Cesium Atoms. 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(2015). Spectroscopy of Ba andBa+deposits in solid xenon for barium tagging in nEXO. Physical Review A, 91(2). doi:10.1103/physreva.91.022505Brunner, T., Fudenberg, D., Varentsov, V., Sabourov, A., Gratta, G., Dilling, J., … Albert, J. B. (2015). An RF-only ion-funnel for extraction from high-pressure gases. International Journal of Mass Spectrometry, 379, 110-120. doi:10.1016/j.ijms.2015.01.003Nygren, D. R. (2016). Detection of the barium daughter in 136Xe →136Ba+2e− by in situ single-molecule fluorescence imaging. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 824, 2-5. doi:10.1016/j.nima.2015.11.038Jones, B. J. P., McDonald, A. D., & Nygren, D. R. (2016). Single molecule fluorescence imaging as a technique for barium tagging in neutrinoless double beta decay. Journal of Instrumentation, 11(12), P12011-P12011. doi:10.1088/1748-0221/11/12/p12011Byrnes, N., Foss, F. W., Jones, B. J. ., McDonald, A. D., Nygren, D. R., … Thapa, P. (2019). Progress toward Barium Tagging in High Pressure Xenon Gas with Single Molecule Fluorescence Imaging. Journal of Physics: Conference Series, 1312, 012001. doi:10.1088/1742-6596/1312/1/012001McDonald, A. D., Jones, B. J. P., Nygren, D. R., Adams, C., Álvarez, V., Azevedo, C. D. R., … Cárcel, S. (2018). Demonstration of Single-Barium-Ion Sensitivity for Neutrinoless Double-Beta Decay Using Single-Molecule Fluorescence Imaging. Physical Review Letters, 120(13). doi:10.1103/physrevlett.120.132504(2019). Imaging individual barium atoms in solid xenon for barium tagging in nEXO. Nature, 569(7755), 203-207. doi:10.1038/s41586-019-1169-4Thapa, P., Arnquist, I., Byrnes, N., Denisenko, A. A., Foss, F. W., Jones, B. J. P., … Woodruff, K. (2019). Barium Chemosensors with Dry-Phase Fluorescence for Neutrinoless Double Beta Decay. 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ELECTRICAL BREAKDOWN IN XENON AND KRYPTON AT ULTRAHIGH FREQUENCIES. Canadian Journal of Physics, 37(10), 1166-1170. doi:10.1139/p59-133Park, J., Henins, I., Herrmann, H. W., & Selwyn, G. S. (2001). Gas breakdown in an atmospheric pressure radio-frequency capacitive plasma source. Journal of Applied Physics, 89(1), 15-19. doi:10.1063/1.1323754Moravej, M., Yang, X., Nowling, G. R., Chang, J. P., Hicks, R. F., & Babayan, S. E. (2004). Physics of high-pressure helium and argon radio-frequency plasmas. Journal of Applied Physics, 96(12), 7011-7017. doi:10.1063/1.1815047Borg Dezani, V., & Ginoux, J. L. (1994). Investigation of breakdown voltage curves for pure helium and silane–helium mixtures. Physics of Plasmas, 1(4), 1060-1063. doi:10.1063/1.870786McDonald, A. D., Woodruff, K., Atoum, B. A., González-Díaz, D., Jones, B. J. P., Adams, C., … Azevedo, C. D. . (2019). Electron drift and longitudinal diffusion in high pressure xenon-helium gas mixtures. 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    NEXT-CRAB-0: A High Pressure Gaseous Xenon Time Projection Chamber with a Direct VUV Camera Based Readout

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    The search for neutrinoless double beta decay (0νββ0\nu\beta\beta) remains one of the most compelling experimental avenues for the discovery in the neutrino sector. Electroluminescent gas-phase time projection chambers are well suited to 0νββ0\nu\beta\beta searches due to their intrinsically precise energy resolution and topological event identification capabilities. Scalability to ton- and multi-ton masses requires readout of large-area electroluminescent regions with fine spatial resolution, low radiogenic backgrounds, and a scalable data acquisition system. This paper presents a detector prototype that records event topology in an electroluminescent xenon gas TPC via VUV image-intensified cameras. This enables an extendable readout of large tracking planes with commercial devices that reside almost entirely outside of the active medium.Following further development in intermediate scale demonstrators, this technique may represent a novel and enlargeable method for topological event imaging in 0νββ0\nu\beta\beta.Comment: 32 Pages, 22 figure

    A Compact Dication Source for Ba2+^{2+} Tagging and Heavy Metal Ion Sensor Development

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    We present a tunable metal ion beam that delivers controllable ion currents in the picoamp range for testing of dry-phase ion sensors. Ion beams are formed by sequential atomic evaporation and single or multiple electron impact ionization, followed by acceleration into a sensing region. Controllability of the ionic charge state is achieved through tuning of electrode potentials that influence the retention time in the ionization region. Barium, lead, and cobalt samples have been used to test the system, with ion currents identified and quantified using a quadrupole mass analyzer. Realization of a clean Ba2+\mathrm{Ba^{2+}} ion beam within a bench-top system represents an important technical advance toward the development and characterization of barium tagging systems for neutrinoless double beta decay searches in xenon gas. This system also provides a testbed for investigation of novel ion sensing methodologies for environmental assay applications, with dication beams of Pb2+^{2+} and Cd2+^{2+} also demonstrated for this purpose

    Difficult tracheal intubation in neonates and infants. NEonate and Children audiT of Anaesthesia pRactice IN Europe (NECTARINE): a prospective European multicentre observational study

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    BACKGROUND: Neonates and infants are susceptible to hypoxaemia in the perioperative period. The aim of this study was to analyse interventions related to anaesthesia tracheal intubations in this European cohort and identify their clinical consequences. METHODS: We performed a secondary analysis of tracheal intubations of the European multicentre observational trial (NEonate and Children audiT of Anaesthesia pRactice IN Europe [NECTARINE]) in neonates and small infants with difficult tracheal intubation. The primary endpoint was the incidence of difficult intubation and the related complications. The secondary endpoints were the risk factors for severe hypoxaemia attributed to difficult airway management, and 30 and 90 day outcomes. RESULTS: Tracheal intubation was planned in 4683 procedures. Difficult tracheal intubation, defined as two failed attempts of direct laryngoscopy, occurred in 266 children (271 procedures) with an incidence (95% confidence interval [CI]) of 5.8% (95% CI, 5.1–6.5). Bradycardia occurred in 8% of the cases with difficult intubation, whereas a significant decrease in oxygen saturation (SpO2<90% for 60 s) was reported in 40%. No associated risk factors could be identified among co-morbidities, surgical, or anaesthesia management. Using propensity scoring to adjust for confounders, difficult anaesthesia tracheal intubation did not lead to an increase in 30 and 90 day morbidity or mortality. CONCLUSIONS: The results of the present study demonstrate a high incidence of difficult tracheal intubation in children less than 60 weeks post-conceptual age commonly resulting in severe hypoxaemia. Reassuringly, the morbidity and mortality at 30 and 90 days was not increased by the occurrence of a difficult intubation event

    Evolution of the use of corticosteroids for the treatment of hospitalised COVID-19 patients in Spain between March and November 2020: SEMI-COVID national registry

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    Objectives: Since the results of the RECOVERY trial, WHO recommendations about the use of corticosteroids (CTs) in COVID-19 have changed. The aim of the study is to analyse the evolutive use of CTs in Spain during the pandemic to assess the potential influence of new recommendations. Material and methods: A retrospective, descriptive, and observational study was conducted on adults hospitalised due to COVID-19 in Spain who were included in the SEMI-COVID- 19 Registry from March to November 2020. Results: CTs were used in 6053 (36.21%) of the included patients. The patients were older (mean (SD)) (69.6 (14.6) vs. 66.0 (16.8) years; p < 0.001), with hypertension (57.0% vs. 47.7%; p < 0.001), obesity (26.4% vs. 19.3%; p < 0.0001), and multimorbidity prevalence (20.6% vs. 16.1%; p < 0.001). These patients had higher values (mean (95% CI)) of C-reactive protein (CRP) (86 (32.7-160) vs. 49.3 (16-109) mg/dL; p < 0.001), ferritin (791 (393-1534) vs. 470 (236- 996) µg/dL; p < 0.001), D dimer (750 (430-1400) vs. 617 (345-1180) µg/dL; p < 0.001), and lower Sp02/Fi02 (266 (91.1) vs. 301 (101); p < 0.001). Since June 2020, there was an increment in the use of CTs (March vs. September; p < 0.001). Overall, 20% did not receive steroids, and 40% received less than 200 mg accumulated prednisone equivalent dose (APED). Severe patients are treated with higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%. Conclusions: Patients with greater comorbidity, severity, and inflammatory markers were those treated with CTs. In severe patients, there is a trend towards the use of higher doses. The mortality benefit was observed in patients with oxygen saturation </=90%
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