Monitorización de errores de medicación en dispensación individualizada mediante el método "carro centinela": comparación entre dos sistemas de distribución en dosis unitaria

Los errores de medicación (EM) en el ámbito hospitalario suponen un problema clínico relevante que implica un riesgo potencial para el paciente, a la vez que es fuente de eventuales demandas e indemnizaciones. La reducción de EM durante la Prescripción y Transcripción, principalmente tras la introducción de sistemas de prescripción electrónica, ha sido objeto de numerosos estudios. Sin embargo, la generación de EM durante la Dispensación o fases del proceso farmacoterapéutico hasta la Administración final del fármaco y principal responsabilidad de los Servicios de Farmacia, ha sido escasamente analizada. Objetivo: Analizar el impacto sobre la calidad del proceso de dispensación en dosis unitarias (DU) como consecuencia de su automatización progresiva, mediante la comparación de dos sistemas de distribución y su monitorización con el método Carro Centinela (CC). Método: Diseño y Ámbito del estudio: Estudio observacional, prospectivo y con muestreo aleatorizado, realizado en dos periodos de tiempo: antes, (Sistema semimanual, SM) y después de la automatización completa (Sistema AC) del proceso de Dispensación. Metodología: Monitorización durante 24 h de un carro de medicación, seleccionado semanalmente de forma randomizada (Carro Centinela, CC), para la determinación y registro de las siguientes Variables: Variable(s) dependiente(s): Errores de medicación (EM), Reclamaciones (R ) y Devoluciones (D) desde las Unidades de Hospitalización (UH). Variables independientes: Administrativas y demográficas, Clínicas (Tipo de UH, Sistema de dispensación, Medicación y tipo y causa de EM, causa de R, causa de D) y operativas (tiempo de técnico y coste). Análisis estadístico: Estadística descriptiva, comparación de medias (Prueba T o análisis de la varianza) para variables cuantitativas y proporciones (prueba z o de Poisson) para variables cualitativas. Riesgo Relativo (RR) entre ambos periodos para las principales variables dependientes y predictivas. Análisis multivariable de parámetros clínicos y operativos que pudieran tener relación con la generación de EM (regresión logística con modelo de efectos mixtos). Análisis de costes. Resultados: Se monitorizaron 130 carros (19973 líneas de medicación) correspondientes a 19 UH durante el primer periodo (Sistema SM) y 52 carros (11782 líneas, 21 UH) en el segundo (Sistema AC). Se registró una disminución estadísticamente significativa en la tasa de errores entre los Sistemas SM y AC: 1,73% vs 1,39%; RR [IC 95%]: 0,81 [0,67-0,97] así como un aumento estadísticamente significativo en la tasa de devoluciones: 4,9% vs 6,17%; RR [IC 95%]: 1,26 [1,15-1,38]. No se observó diferencia significativa respecto a la tasa de R entre ambos periodos. Entre los tipos y causas de EM, presentaron mayor prevalencia la ausencia de medicación (32,2%) y el error humano (49,1%), respectivamente. La medicación no dispensada (24,7%) y el alta del paciente (31,1%) fueron las causas más frecuentes de R y D, respectivamente. Además, el análisis multivariable (regresión logística con modelo de efectos mixtos) identificó, un menor riesgo de EM durante el segundo periodo (Sistema AC), asociado a los efectos aleatorios cruzados de las variables UH y tipo de Medicación, con una Odds Ratio de 0,16 [0,12-0,22]. Se observó una disminución estadísticamente significativa de 17,5 min (51,8 %) por cada 100 líneas de medicación, entre los sistemas de dispensación SM y AC que se tradujo en un ahorro estimado de 3,23 € por cada 100 líneas de medicación dispensada y neto acumulado anual de 56200,5€ (42258,8 € incluyendo amortización de equipos). Conclusiones: La implantación de un nuevo sistema de preparación-dispensación de medicamentos en un Servicio de Farmacia, basado en su automatización progresiva y monitorización mediante el método del Carro Centinela (CC) permite mejorar la eficacia del sistema (menos EM) y su efectividad (menor tiempo operativo y con menor coste). Palabras Clave: Errores de Medicación, Dispensación, Dosis Unitaria, Control de CalidadMedication errors (ME) in hospitals pose a significant clinical problem involving a potential risk to the patient, as well as a source of possible claims and compensations. ME reduction in the Prescription and Transcription phases, especially after the introduction of electronic prescribing systems, has been the subject of numerous studies. However, the generation of ME during Dispensing including preparing and distributing medication up to its final Administration, and primary responsibility of Pharmacy Services, has been scarcely analyzed. Aims: To analyze the impact on the quality of the process of unit dose (UD) dispensing as a result of its progressive automation, by comparing two systems of distribution and monitoring with the Sentinel Cart (SC) method. Methods: Design and Scope of the study: Observational, prospective and randomized sampling, conducted in two study periods: before (semi-manual (SM) system) and, after full automation ((FA) system) of the dispensing process; Methodology: Monitoring for 24 h every week of a randomly selected medication cart (SC), for the determination and registration of the following Variables: Dependent(s) variable(s): Medication Errors (ME) Claims (C) and Returns (R) of medication from the wards. Independent variables: Administrative and demographic, Clinical (ward specialty and type of medication, type and cause of ME, cause of C, cause of R)) and operational (technical time and cost). Statistical analysis: Descriptive statistics, comparison of means (T test or analysis of variance) for quantitative variables and proportions comparison (z test or Poisson test) for qualitative variables. Relative Risk (RR) between both periods for main dependent and independent variables. Multivariate analysis of clinical and operational parameters that could be related to the generation of ME (mixed effects analysis). Cost analysis. Results: 130 carts (19,973 lines of medication) for 19 UH during the first Period (SM system), and 52 carts (11,782 lines, 21 UH) in the second (FA system) were monitored. A statistically significant decrease in the rate of ME between SM and FA systems: 1.73% vs 1.39%; RR [IC 95%]: 0.81 [0.67-0.97], as well as a stastically significant increase in the rates of D: 4.9% vs 6.17%; RR [C 95%]: 1.26 [1.15-1.38] were found. No statistically significant difference were found in the rates of C between the two systems. Among the types and causes of ME, absence of medication (32.2%) and human error (49.1%) showed the highest prevalence, respectively. Non dispensed medication (24.7%) and patient discharge (31.1%) were the most frequent causes for C and R, respectively. In addition, multivariate analysis (logistic regression with mixed effects analysis) identified a decreased risk of ME during the second period (FA system), associated with the crossed random effect of the variables Ward Specialty and type of Medication and Odds Ratio 0.16 [0.12-0.22]. A statistically significant decrease of 17,5 min (51,8%) per 100 lines of medication, between SM and FA dispensing systems, was observed. This resulted in an estimated savings of € 3,23 per 100 lines of dispensed medication and annual net accumulated of 56200,5€ (42258,8 € including amortization of equipment). Conclusions: The implementation of a new system for medication preparing and dispensing, based on its progressive automation and monitoring by the SC method, improves system efficiency (less ME) and effectiveness (lower technicians time consuming and operating costs). Key words: Medication Errors, Dispensing, Unit Dose, Quality Control

Sensitivity plots for WIMP modulation searches

Prospects of WIMP searches using the annual modulation signature are discussed on statistical grounds, introducing sensitivity plots for the WIMP-nucleon scalar cross section.Comment: 3 pages, 2 figures, talk given at TAUP'99, september 199

Standardization of hake LPUE series of the Galician set-longline fleet in Subarea VII

WGHMM (now WGBIE) identified a problem in the assessment of northern hake in relation to the scarce information on the abundance of large fish. 2004 WKSOUTH tested the inclusion in SS3 of Galician LPUEs from set-longline fleet targeting hake in ICES Subarea VII. This metier catches mainly adults. However, during WGBIE 2014, a serious inconsistency was detected when updating this LPUE time series, related to the assumption of the average fishing days by trip employed along the time series. The current working document provides the revision of this LPUE series by applying the actual number of fishing days by trip recorded in logbooks, which has varied greatly in the final part of the time series. The revised LPUE indices obtained were then tested in the assessment of northern hake stock. The difference in results between the assessments without LLPUE and the assessment which includes the new LPUE series were minor. In the initial part of the time series the LPUE matched the abundance closely but in the last period the increase in the LLPUE was much lower than the increase in the stock abundance

Pesticide Exposure Alters Follicle-Stimulating Hormone Levels in Mexican Agricultural Workers

Organophosphorous pesticides (OPs) are suspected of altering reproductive function by reducing brain acetylcholinesterase activity and monoamine levels, thus impairing hypothalamic and/or pituitary endocrine functions and gonadal processes. Our objective was to evaluate in a longitudinal study the association between OP exposure and serum levels of pituitary and sex hormones. Urinary OP metabolite levels were measured by gas–liquid chromatography, and serum pituitary and sex hormone levels by enzymatic immunoassay and radioimmunoassay in 64 men. A total of 147 urine and blood samples were analyzed for each parameter. More than 80% of the participants had at least one OP metabolite in their urine samples. The most frequent metabolite found was diethylthiophosphate (DETP; 55%), followed by diethylphosphate (DEP; 46%), dimethylthiophosphate (DMTP; 32%), and dimethyldithiophosphate (DMDTP; 31%). However, the metabolites detected at higher concentrations were DMTP, DEP, DMDTP, and dimethylphosphate. There was a high proportion of individuals with follicle-stimulating hormone (FSH) concentrations outside the range of normality (48%). The average FSH serum levels were higher during the heavy pesticide spraying season. However, a multivariate analysis of data collected in all periods showed that serum FSH levels were negatively associated with urinary concentrations of both DMTP and DMDTP, whereas luteinizing hormone (LH) was negatively associated with DMTP. We observed no significant associations between estradiol or testosterone serum levels with OP metabolites. The hormonal disruption in agricultural workers presented here, together with results from experimental animal studies, suggests that OP exposure disrupts the hypothalamic–pituitary endocrine function and also indicates that FSH and LH are the hormones most affected

Gaseous time projection chambers for rare event detection: Results from the T-REX project. II. Dark matter

As part of the T-REX project, a number of R&D and prototyping activities have been carried out during the last years to explore the applicability of Micromegas-read gaseous TPCs in rare event searches like double beta decay (DBD), axion research and low-mass WIMP searches. While in the companion paper we focus on DBD, in this paper we focus on the results regarding the search for dark matter candidates, both axions and WIMPs. Small ultra-low background Micromegas detectors are used to image the x-ray signal expected in axion helioscopes like CAST at CERN. Background levels as low as $0.8\times 10^{-6}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$ have already been achieved in CAST while values down to $\sim10^{-7}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$ have been obtained in a test bench placed underground in the Laboratorio Subterr\'aneo de Canfranc. Prospects to consolidate and further reduce these values down to $\sim10^{-8}$ c keV$^{-1}$cm$^{-2}$s$^{-1}$will be described. Such detectors, placed at the focal point of x-ray telescopes in the future IAXO experiment, would allow for 10$^5$ better signal-to-noise ratio than CAST, and search for solar axions with $g_{a\gamma}$ down to few 10$^{12}$ GeV$^{-1}$, well into unexplored axion parameter space. In addition, a scaled-up version of these TPCs, properly shielded and placed underground, can be competitive in the search for low-mass WIMPs. The TREX-DM prototype, with $\sim$0.300 kg of Ar at 10 bar, or alternatively $\sim$0.160 kg of Ne at 10 bar, and energy threshold well below 1 keV, has been built to test this concept. We will describe the main technical solutions developed, as well as the results from the commissioning phase on surface. The anticipated sensitivity of this technique might reach $\sim10^{-44}$ cm$^2$ for low mass ($<10$ GeV) WIMPs, well beyond current experimental limits in this mass range.Comment: Published in JCAP. New version with erratum incorporated (new figure 14

Sensitivity plots for WIMP direct detection using the annual modulation signature

Annual modulation due to the Earth's motion around the Sun is a well known signature of the expected WIMP signal induced in a solid state underground detector. In the present letter we discuss the prospects of this technique on statistical grounds, introducing annual-modulation sensitivity plots for the WIMP-nucleon scalar cross section for different materials and experimental conditions. The highest sensitivity to modulation is found in the WIMP mass interval 10 GeV< m_W < 130 GeV, the actual upper limit depending from the choice of the astrophysical parameters, while the lowest values of the explorable WIMP-nucleon elastic cross-sections fall in most cases within one order of magnitude of the sensitivities of present direct detection WIMP searches.Comment: 24 pages, ReVTeX, 9 figures, submitted to Astroparticle Physic

Short-term impacts of salinity pulses on ionic ratios of the seagrasses Thalassia testudinum and Halodule wrightii

We examined the effects of short-term salinity pulses on ion accumulation in the seagrasses Thalassia testudinum and Halodule wrightii. Plant fragments were exposed for approximately 1 week to 10, 23 (ambient salinity), 30, 40, 50 and 70 psu. The concentrations of total ions, Cl− and Na+ increased with higher salinity in leaves and rhizomes of both seagrass species. In contrast, the concentrations of K+ and Ca2+ generally decreased with higher salinity, although the decrease was relatively small and only observed at extreme salinities. Our results indicate the concentrations of Cl− and Na+ were higher in rhizomes than in leaves, possibly reflecting effective ion exclusion mechanisms in leaves. Under ambient (control) salinity the ratios K+/Na+ and Ca2+/Na+ were 38% and 46% higher in H. wrightii than in T. testudinum leaves, which support the notion that H. wrightii is more tolerant of salinity increases than T. testudinum. In concert, our results show novel observations of ion osmolyte concentrations in these seagrass species that point to adaptive responses to salinity pulses. Despite these adaptive responses, pulses of extremely high salinity (>50 psu) lasting approximately 1 week are detrimental to these seagrass species.This research was financed by a grant of University of Alicante

Background studies and shielding effects for the TPC detector of the CAST experiment

Sunset solar axions traversing the intense magnetic field of the CERN Axion Solar Telescope (CAST) experiment may be detected in a Time Projection Chamber (TPC) detector, as X-rays signals. These signals could be masked, however, by the inhomogeneous background of materials in the experimental site. A detailed analysis, based on the detector characteristics, the background radiation at the CAST site, simulations and experimental results, has allowed us to design a shielding which reduces the background level by a factor of ~4 compared to the detector without shielding, depending on its position, in the energy range between 1 and 10 keV. Moreover, this shielding has improved the homogeneity of background measured by the TPC.Comment: 14 pages, 5 figures, accepted in New Journal of Physic