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1.
BMC Med Educ ; 24(1): 607, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824537

RESUMEN

BACKGROUND: Healthcare systems worldwide face challenges related to patient safety, quality of care, and interprofessional collaboration. Simulation-based team training has emerged as a promising approach to address some of these challenges by providing healthcare professionals with a controlled and safe environment to enhance their teamwork and communication skills. The purpose of this study protocol is to describe an intervention using simulation-based team training in pediatric departments. METHODS: Using a parallel-group, non-randomized controlled trial design, a simulation-based team training intervention will be implemented across four pediatric departments in Denmark. Another four pediatric departments will serve as controls. The intervention implies that healthcare professionals engage in simulation-based team training at a higher quantity and frequency than they did previously. Development of the intervention occurred from April 2022 to April 2023. Implementation of the intervention occurs from April 2023 to April 2024. Evaluation of the intervention is planned from April 2024 to April 2025. All simulation activity both before and during the intervention will be registered, making it possible to compare outcomes across time periods (before versus after) and across groups (intervention versus control). To evaluate the effects of the intervention, we will conduct four analyses. Analysis 1 investigates if simulation-based team training is related to sick leave among healthcare professionals. Analysis 2 explores if the simulation intervention has an impact on patient safety culture. Analysis 3 examines if simulation-based team training is associated with the treatment of critically ill newborns. Finally, Analysis 4 conducts a cost-benefit analysis, highlighting the potential return on investment. DISCUSSION: The implemented simulation-based team training intervention can be defined as a complex intervention. Following the Medical Research Council framework and guidelines, the intervention in this project encompasses feasibility assessment, planning of intervention, implementation of intervention, and rigorous data analysis. Furthermore, the project emphasizes practical considerations such as stakeholder collaboration, facilitator training, and equipment management. TRIAL REGISTRATION: Registered as a clinical trial on clinicaltrials.gov, with the identifier NCT06064045.


Asunto(s)
Grupo de Atención al Paciente , Entrenamiento Simulado , Humanos , Dinamarca , Pediatría/educación , Personal de Salud/educación , Ensayos Clínicos Controlados no Aleatorios como Asunto , Seguridad del Paciente
2.
J Radiol Prot ; 41(4)2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-33975295

RESUMEN

The International Commission on Radiation Units and Measurements (ICRU) Report Number 95 (2020 Operational quantities for external radiation exposureICRU Rep. 95 J. ICRU20) recommends new definitions ffor operational quantities as estimators of the International Commission on Radiological Protection radiation protection quantities. As part of this report, dose coefficients for neutron fluences are included for energies from 10-9-50 MeV. For lens of the eye dosimetry, several changes in the ICRU recommended quantities are of particular interest. First, an updated eye model is used that includes segmentation of the sensitive lens region. In addition, the use of absorbed dose instead of dose equivalent has been selected as the appropriate operational quantity since deterministic (i.e. non-stochastic) effects are of primary importance for the lens of the eye. The ICRU report also addresses computational parameters, such as absorbed dose tally volumes, depths, source areas and source rotational angles. In this work, neutron dose coefficients calculated for the lens of the eye in support of the ICRU report are presented. Dose coefficients for mono-energetic neutrons and reference neutron spectra are presented. The source is a parallel beam, and the mono-energetic dose coefficients are provided for rotational angles with respect to the front face of the head ranging from 0°-90°. In addition, monoenergetic dose coefficients for the parallel beam incident on the back of the head (180°) and for a rotational source geometry where the head is irradiated from all angles are reported. For all scenarios, absorbed doses to the complete lens and the sensitive volume of each eye were calculated. Eye lens absorbed dose coefficients,Dp,slab(3,0)/Φ, were also calculated in an ICRU tissue slab phantom at a depth of 3 mm for a parallel beam irradiating the slab perpendicular to the front face, and these results are compared to the values determined using the eye phantom.


Asunto(s)
Cristalino , Protección Radiológica , Neutrones , Dosis de Radiación , Radiometría
3.
J Radiol Prot ; 40(2): 554-582, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32176871

RESUMEN

A draft report by the International Commission on Radiation Units and Measurements (ICRU) Report Committee 26 (RC26) will recommend alternative definitions of the operational quantities that are better estimators of radiation protection quantities. Dose coefficients for use with physical field quantities-fluence and, for photons, air kerma-are given for various particle types over a broad energy range. For the skin dosimetry, several changes are of particular interest. Specifically, the use of absorbed dose instead of dose equivalent has been selected as the operational quantity since deterministic effects are of primary interest in the skin. In addition, newly recommended phantoms are specified for computing the operational dose coefficients. The report also addresses computational approaches such as tally volumes, depths, source areas, and rotational angles. In this work, dose coefficients calculated for local skin in support of the ICRU report are presented. Energy-dependent dose coefficients were calculated in phantoms specified for the trunk (slab), the ankle or wrist (pillar), and the finger (rod). The phantom specifications in this work were taken directly from the draft report. Full transport of secondary charged particles from neutron interactions was performed and an analysis of the depth-dose profiles in the slab phantom is presented, The last complete set of neutron dose coefficients for the extremities was published more than 25 years ago. Given the limited data available, it is difficult for many facilities to obtain clear guidance on how monitoring should be performed and how dosimeters should be calibrated so spectra from commonly encountered neutron sources were used to generate source-specific dose coefficients in each of the phantoms. Both energy-dependent and source-specific dose coefficients are provided for rotational angles up to 180 degrees for the rod and pillar phantoms and up to 75 degrees for the slab phantom.


Asunto(s)
Extremidades/efectos de la radiación , Neutrones , Dosis de Radiación , Radiometría/métodos , Piel/efectos de la radiación , Humanos , Modelos Anatómicos , Protección Radiológica
4.
Radiat Environ Biophys ; 56(3): 255-267, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28493137

RESUMEN

The Oak Ridge National Laboratory Center for Radiation Protection Knowledge has undertaken calculations related to various environmental exposure scenarios. A previous paper reported the results for submersion in radioactive air and immersion in water using age-specific mathematical phantoms. This paper presents age-specific effective dose rate coefficients derived using stylized mathematical phantoms for exposure to contaminated soils. Dose rate coefficients for photon, electron, and positrons of discrete energies were calculated and folded with emissions of 1252 radionuclides addressed in ICRP Publication 107 to determine equivalent and effective dose rate coefficients. The MCNP6 radiation transport code was used for organ dose rate calculations for photons and the contribution of electrons to skin dose rate was derived using point-kernels. Bremsstrahlung and annihilation photons of positron emission were evaluated as discrete photons. The coefficients calculated in this work compare favorably to those reported in the US Federal Guidance Report 12 as well as by other authors who employed voxel phantoms for similar exposure scenarios.


Asunto(s)
Fantasmas de Imagen , Exposición a la Radiación/análisis , Radiometría/instrumentación , Contaminantes Radiactivos del Suelo/análisis , Adolescente , Adulto , Niño , Preescolar , Humanos , Lactante , Recién Nacido
5.
Diabet Med ; 33(4): 515-22, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26333180

RESUMEN

AIMS: To examine trends in diabetes treatment in Danish children and adolescents with Type 1 diabetes mellitus, comparing treatment intensity with metabolic outcomes in the population, and to describe the challenges of population-based registries in a clinical setting with rapidly changing treatment methods. METHODS: This observational study is based on the Danish national population registry of childhood diabetes, which includes 99% of children diagnosed with Type 1 diabetes before the age of 15 years. We included 4527 people diagnosed between 2000 and 2012. Self-monitored blood glucose measurements, insulin injections/boluses, treatment method and metabolic control quantifications were analysed and adjusted for the effects of gender and ethnicity, the combined effect of age, visit year and duration, and for the random effects of individual and hospital settings. RESULTS: Treatment was intensified via an increasing number of self-monitored blood glucose measurements and injections/boluses. More than six injections/boluses and an increased number of self-monitored blood glucose measurements were significantly associated with lower metabolic control. No reduction, however, in the overall mean HbA1c concentration was observed between 2005 [66 mmol/mol (8.2%)] and 2012 [65 mmol/mol (8.1%)]. Changed registration practices in 2009 introduced artificial jumps in data. CONCLUSIONS: Intensifying treatment alone does not lead to improved metabolic control in the overall population despite the appearance of lower HbA1c in individuals with a greater number of self-monitored blood glucose measurements and injections/boluses. The contradictory results reflect difficulties in using observational studies to predict results of intervention in the individual. Data collected from population-based registries need to be adjusted continuously to reflect changes in care.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Monitoreo de Drogas , Hiperglucemia/prevención & control , Hipoglucemia/prevención & control , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Medicina de Precisión , Adolescente , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea , Niño , Preescolar , Estudios de Cohortes , Dinamarca/epidemiología , Diabetes Mellitus Tipo 1/sangre , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/análisis , Humanos , Hiperglucemia/epidemiología , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Insulina/efectos adversos , Insulina/uso terapéutico , Masculino , Guías de Práctica Clínica como Asunto , Sistema de Registros , Riesgo
6.
Radiat Meas ; 45(10): 1233-1237, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22888283

RESUMEN

In a recent work, we constructed modular multisphere system which expands upon the design of an existing, commercially available Bonner sphere system by adding concentric shells of copper, tungsten, or lead. Our modular multisphere system is referred to as the Bonner Sphere Extension (BSE). The BSE was tested in a high energy neutron beam (thermal to 800 MeV) at Los Alamos Neutron Science Center and provided improvement in the measurement of the neutron spectrum in the energy regions above 20 MeV when compared to the standard BSS (Burgett, 2008 and Howell et al., 2009).However, when the initial test of the system was carried-out at LANSCE, the BSE had not yet been calibrated. Therefore the objective of the present study was to perform calibration measurements. These calibration measurements were carried out using monoenergetic neutron ISO 8529-1 reference beams at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig, Germany. The following monoenergetic reference beams were used for these experiments: 14.8 MeV, 1.2 MeV, 565 keV, and 144 keV. Response functions for the BSE were calculated using the Monte Carlo N-Particle Code, eXtended (MCNPX). The percent difference between the measured and calculated responses was calculated for each sphere and energy. The difference between measured and calculated responses for individual spheres ranged between 7.9 % and 16.7 % and the arithmetic mean for all spheres was (10.9 ± 1.8) %. These sphere specific correction factors will be applied for all future measurements carried-out with the BSE.

11.
Schmerz ; 23(4): 385-91, 2009 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-19399524

RESUMEN

BACKGROUND: Appropriate postoperative pain therapy is essential for an accelerated recovery. However, coding complex acute pain therapy (OPS 8-919) does not have any impact on hospital revenues. As medical and economic primary data related to this therapy are scarce, hospital data were analysed to identify differences between patients with and without acute pain therapy. MATERIAL AND METHODS: Two patient groups were generated out of an anonymized data set from 372 acute care hospitals in 2005: The case group (G1) included 4,197 patients (OPS 8-919 coded). The control group (G2) contained 61,181 patients (neither OPS 8-919 nor 8-910 nor 8-911 coded). RESULTS: The analysis revealed that patients in G1 had a prolonged mean length of hospital stay (2.5 days). The mean number of diagnoses per case was similar in both groups (G1:6.9, G2:6.6), whereas the mean number of procedures was higher in G1 (G1:8.2, G2:6.2). The difference in mean diagnosis-related group (DRG) revenue per case was about EUR 200 (G1:EUR 9,233, G2:EUR 9,030). CONCLUSION: To validate the results found in this analysis, further evaluations of these patient groups are essential. High-quality documentation and coding in hospitals are required for future studies.


Asunto(s)
Dolor Postoperatorio/epidemiología , Enfermedad Aguda , Analgesia/economía , Analgesia Controlada por el Paciente/economía , Grupos Diagnósticos Relacionados/economía , Documentación , Economía Hospitalaria , Alemania , Humanos , Tiempo de Internación/economía , Dolor Postoperatorio/economía , Sistema de Pago Prospectivo/economía
13.
J Pediatr Endocrinol Metab ; 21(3): 267-73, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18540254

RESUMEN

BACKGROUND: Noonan syndrome (NS) is an autosomal dominant inherited disease, characterized by a distinctive facial appearance, congenital heart defects, and short stature. Treatment with growth hormone (GH) is an option to enhance height, but long-term effects are still unclear. PATIENTS AND METHODS: A cohort of 402 patients (269 males, 133 females), mean age 9.7 years at start with GH, was studied within the KIGS International growth database with respect to long-term response to GH therapy and final height after GH therapy. RESULTS: At the start of GH therapy median height was -2.61 SDS (Tanner 1966 standards). Seventy-three patients who were followed longitudinally for 3 years had an increment in height SDS (Ht SDS) over the first 3 successive years of 0.54, 0.13 and 0.13, respectively. Twenty-four patients had reached their final height after 4-12 years of GH treatment. Their Ht SDS increased from a median of -3.28 to a median of -2.41 at final height. CONCLUSION: This group of patients with NS showed an early response to GH treatment, with an attenuation of this effect thereafter. At final height the median increment of final height was 0.61 SDS according to Tanner standards and 0.97 SDS according to Noonan standards. No serious side effects were reported.


Asunto(s)
Estatura/efectos de los fármacos , Hormona de Crecimiento Humana/uso terapéutico , Síndrome de Noonan/tratamiento farmacológico , Proteínas Recombinantes/uso terapéutico , Niño , Estudios de Cohortes , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Resultado del Tratamiento
14.
Radiat Prot Dosimetry ; 128(3): 289-93, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17681965

RESUMEN

Multisphere neutron spectrometers with active thermal neutron detectors cannot be used in high-intensity radiation fields due to pulse pile-up and dead-time effects. Thus, a multisphere spectrometer using a passive detection system, specifically gold foils, has been investigated in this work. The responses of a gold-foil-based Bonner sphere neutron spectrometer were studied for two different gold-foil holder designs; an aluminium-polyethylene holder and a polyethylene holder. The responses of the two designs were calculated for four incident neutron beam directions, namely, parallel, perpendicular and at +/-45 degrees relative to the flat surface of the foil. It was found that the use of polyethylene holder resulted in a more isotropic response to neutrons for the four incident directions considered. The computed responses were verified by measuring the neutron spectrum of a 252Cf source with known strength.


Asunto(s)
Oro , Neutrones , Análisis Espectral/instrumentación , Calibración , Diseño de Equipo , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad
15.
Radiat Prot Dosimetry ; 178(3): 310-321, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-28981797

RESUMEN

We present fitting equations for estimating effective dose per unit fluence at any photon energy between 10 keV and 10 GeV and any neutron energy between 0.001 eV and 10 GeV. These new equations are based on the latest radiation protection quantities for external radiation exposure found in International Commission on Radiological Protection (ICRP) Publication 116 and incorporate the latest definition of effective dose as described in ICRP Publication 103. The ICRP 116 dose coefficients were fit to piecewise polynomial functions. A total of 8 irradiation geometries were considered: the six in ICRP 116 and two additional geometries presented elsewhere in the literature. The fitting functions generally reproduce the ICRP 116 data to within 3% or better. The functions were used to modify the Monte Carlo N-Particle radiation transport code version 6 (MCNP6) and were applied to a sample problem. The results are intended to be used as a basis for revising the American National Standards Institute/American Nuclear Society 6.1.1-1991 standard.


Asunto(s)
Neutrones , Fotones , Dosis de Radiación , Protección Radiológica/normas , Radiometría/métodos , Humanos , Método de Montecarlo , Órganos en Riesgo/efectos de la radiación
16.
Radiat Prot Dosimetry ; 180(1-4): 10-16, 2018 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-29165634

RESUMEN

Report Committee 26 of the ICRU proposes a set of operational quantities for radiation protection for external radiation, directly based on effective dose and for an extended range of particles and energies. It is accompanied by quantities for estimating deterministic effects to the eye lens and the local skin. The operational quantities are designed to overcome the conceptual and technical shortcomings of those presently in use. This paper describes the proposed operational quantities, and highlights the improvements with respect to the present, legal monitoring quantities.


Asunto(s)
Cristalino/efectos de la radiación , Exposición a la Radiación/efectos adversos , Traumatismos por Radiación/prevención & control , Monitoreo de Radiación/normas , Protección Radiológica/normas , Calibración , Humanos , Agencias Internacionales , Dosis de Radiación , Traumatismos por Radiación/etiología
17.
Health Phys ; 92(2): 179-85, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17220720

RESUMEN

Absorbed dose and dose equivalent conversion coefficients are routinely used in personnel dosimetry programs. These conversion coefficients can be applied to particle fluences or to measured air kerma values to determine appropriate operational monitoring quantities such as the ambient dose equivalent or personal dose equivalent for a specific geometry. For personnel directly handling materials, the absorbed dose to the extremities is of concern. This work presents photon conversion coefficients for two extremity calibration geometries using finger and wrist/arm phantoms described in HPS N13.32. These conversion coefficients have been calculated as a function of photon energy in terms of the kerma and the absorbed dose using Monte Carlo techniques and the calibration geometries specified in HPS N13.32. Additionally, kerma and absorbed dose conversion coefficients for commonly used x-ray spectra and calibration source fields are presented. The kerma values calculated in this work for the x-ray spectra and calibration sources compare well to those listed in HPS N13.32. The absorbed dose values, however, differ significantly for higher energy photons because charged particle equilibrium conditions have not been satisfied for the shallow depth. Thus, the air-kerma-to-dose and exposure-to-dose conversion coefficients for Cs and Co listed in HPS N13.32 overestimate the absorbed dose to the extremities. Applying the conversion coefficients listed in HPS N13.32 for Cs, for example, would result in an overestimate of absorbed dose of 62% for the finger phantom and 55% for the wrist phantom.


Asunto(s)
Extremidades/fisiología , Modelos Biológicos , Fotones , Radiometría/instrumentación , Radiometría/métodos , Carga Corporal (Radioterapia) , Calibración , Simulación por Computador , Humanos , Dosis de Radiación , Radiometría/normas , Efectividad Biológica Relativa
18.
Radiat Prot Dosimetry ; 126(1-4): 626-30, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17525059

RESUMEN

In boron neutron capture therapy and boron neutron capture enhanced fast neutron therapy, the absorbed dose of tissue due to the boron neutron capture reaction is difficult to measure directly. This dose can be computed from the measured thermal neutron fluence rate and the (10)B concentration at the site of interest. A borated tissue-equivalent (TE) ion chamber can be used to directly measure the boron dose in a phantom under irradiation by a neutron beam. Fermilab has two Exradin 0.5 cm(3) Spokas thimble TE ion chambers, one loaded with boron, available for such measurements. At the Fermilab Neutron Therapy Facility, these ion chambers are generally used with air as the filling gas. Since alpha particles and lithium ions from the (10)B(n,alpha)(7)Li reactions have very short ranges in air, the Bragg-Gray principle may not be satisfied for the borated TE ion chamber. A calibration method is described in this paper for the determination of boron capture dose using paired ion chambers. The two TE ion chambers were calibrated in the thermal column of the National Institute of Standards and Technology (NIST) research reactor. The borated TE ion chamber is loaded with 1,000 ppm of natural boron (184 ppm of (10)B). The NIST thermal column has a cadmium ratio of greater than 400 as determined by gold activation. The thermal neutron fluence rate during the calibration was determined using a NIST fission chamber to an accuracy of 5.1%. The chambers were calibrated at two different thermal neutron fluence rates: 5.11 x 10(6) and 4.46 x 10(7)n cm(-2) s(-1). The non-borated ion chamber reading was used to subtract collected charge not due to boron neutron capture reactions. An optically thick lithium slab was used to attenuate the thermal neutrons from the neutron beam port so the responses of the chambers could be corrected for fast neutrons and gamma rays in the beam. The calibration factor of the borated ion chamber was determined to be 1.83 x 10(9) +/- 5.5% (+/- 1sigma) n cm(-2) per nC at standard temperature and pressure condition.


Asunto(s)
Terapia por Captura de Neutrón de Boro/instrumentación , Terapia por Captura de Neutrón de Boro/normas , Neutrones , Monitoreo de Radiación/instrumentación , Monitoreo de Radiación/normas , Protección Radiológica/instrumentación , Protección Radiológica/normas , Ácidos Bóricos/química , Ácidos Bóricos/efectos de la radiación , Calibración , Iones , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos
19.
Radiat Prot Dosimetry ; 175(1): 26-30, 2017 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27574318

RESUMEN

Dose coefficients based on the recommendations of International Commission on Radiological Protection (ICRP) Publication 103 were reported in ICRP Publication 116, the revision of ICRP Publication 74 and ICRU Publication 57 for the six reference irradiation geometries: anterior-posterior, posterior-anterior, right and left lateral, rotational and isotropic. In this work, dose coefficients for neutron irradiation of the body with parallel beams directed upward from below the feet (caudal) and downward from above the head (cranial) using the ICRP 103 methodology were computed using the MCNP 6.1 radiation transport code. The dose coefficients were determined for neutrons ranging in energy from 10-9 MeV to 10 GeV. At energies below about 500 MeV, the cranial and caudal dose coefficients are less than those for the six reference geometries reported in ICRP Publication 116.


Asunto(s)
Neutrones , Dosis de Radiación , Protección Radiológica , Simulación por Computador , Humanos , Método de Montecarlo , Fantasmas de Imagen , Radiometría
20.
Radiat Prot Dosimetry ; 174(4): 439-448, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27522048

RESUMEN

In this article, methods are addressed to reduce the computational time to compute organ-dose rate coefficients using Monte Carlo techniques. Several variance reduction techniques are compared including the reciprocity method, importance sampling, weight windows and the use of the ADVANTG software package. For low-energy photons, the runtime was reduced by a factor of 105 when using the reciprocity method for kerma computation for immersion of a phantom in contaminated water. This is particularly significant since impractically long simulation times are required to achieve reasonable statistical uncertainties in organ dose for low-energy photons in this source medium and geometry. Although the MCNP Monte Carlo code is used in this paper, the reciprocity technique can be used equally well with other Monte Carlo codes.


Asunto(s)
Método de Montecarlo , Fantasmas de Imagen , Radiometría , Simulación por Computador , Fotones , Programas Informáticos , Agua
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