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RESUMEN La anemia durante la gestación es considerada un problema de salud pública debido a las prevalencias alarmantes que se presentan a nivel mundial. La medida optada por los diversos gobiernos es la administración masiva con suplementos de hierro. Sin embargo, actualmente existe evidencia contradictoria sobre el consumo de hierro, el exceso de su consumo y los potenciales riesgos durante la gestación tanto para la madre como para el producto. Para la gestación se requiere de 1 gramo adicional de hierro para la madre, el feto, la placenta y el parto. Esto genera un aumento de la masa roja del 20%; pero, para evitar la hemoconcentración el volumen plasmático se expande casi el 50%, generando una hemodilución fisiológica. Para la gestante no se ha establecido un criterio que permita diferenciar la anemia por deficiencia de hierro, de la anemia fisiológica debido al proceso normal de hemodilución. En el caso de Perú y de países con población residente de altura, se suma una problemática adicional, el factor de corrección de hemoglobina por residencia en la altura, el cual es un valor determinado de forma matemática y arbitraria. Las evidencias recientes sugieren que este factor debe ser reevaluado, debido a que no considera la etnia y el tiempo generacional de residencia en la altura. La presente revisión muestra una actualización y discusión de los criterios de diagnóstico de anemia, la suplementación con hierro, el factor de corrección de hemoglobina por altura de residencia y el impacto de la contaminación ambiental sobre el proceso de gestación.
ABSTRACT Anemia during pregnancy is considered a public health problem, due to the alarming prevalence worldwide. The measure chosen by various governments is massive iron supplements. However, there is currently contradictory evidence on iron intake, excess consumption, and potential risks during pregnancy for both the mother and child. For gestation, an additional 1 gram of iron is required for the mother, fetus, placenta, and delivery. This generates an increase in red mass of 20% but to avoid hemoconcentration the plasma volume expands by almost 50% generating a physiological hemodilution. For pregnant women, no criteria have been established to differentiate iron deficiency anemia and physiological anemia due to the normal process of hemodilution. In the case of Peru and countries with high altitude resident population, there is an additional problem, the hemoglobin correction factor for high altitude residence, which is a mathematically and arbitrarily determined value. Recent evidence suggests that this factor should be reevaluated because it does not consider ethnicity and generational time of residence at high altitude. The present review provides an update and discussion of the diagnostic criteria for anemia, iron supplementation, the hemoglobin correction factor for altitude of residence, and the impact of environmental pollution on the gestation process.
RESUMO
The Weather Research and Forecasting-Chemistry (WRF-Chem) model was used to develop an operational air quality forecast system for the Metropolitan Area of Lima-Callao (MALC), Peru, that is affected by high particulate matter concentrations episodes. In this work, we describe the implementation of an operational air quality-forecasting platform to be used in the elaboration of public policies by decision makers, and as a research tool to evaluate the formation and transport of air pollutants in the MALC. To examine the skills of this new system, an air pollution event in April 2016 exhibiting unusually elevated PM2.5 concentrations was simulated and compared against in situ air quality measurements. In addition, a Model Output Statistic (MOS) algorithm has been developed to improve outputs of inhalable particulate matter (PM10) and fine particulate matter (PM2.5) from the WRF-Chem model. The obtained results showed that MOS increased the accuracy in terms of mean normalized bias for PM10 and PM2.5 from -43.1% and 71.3% to 3.1%, 7.3%, respectively. In addition, the mean normalized gross error for PM10 and PM2.5 were reduced from 48% and 92.3% to 13.4% and 10.1%, respectively. The WRF-Chem Model results showed an appropriate relationship between of temperature and relative humidity with observations during April 2016. Mean normalized bias for temperature and relative humidity were approximately - 0.6% and 1.1% respectively. In addition, the mean normalized gross error for temperature and relative humidity were approximately 4.0% and 0.1% respectively. The results showed that this modelling system can be a useful tool for the analysis of air quality in MALC.