Medicina humana espacial: Performance fisiológico y contramedidas para mejorar la salud del astronauta / Human Space Medicine: Physiological Performance And Countermeasures To Improve The Astronaut's Health

Se presenta este artículo de revisión con base en la evidencia científica actual sobre medicina espacial enfocada en fisiología humana y sus contramedidas. Por lo cual se realizó una búsqueda bibliográfica no sistemática de artículos científicos y libros de investigación en inglés-español de los últimos 7 años, que detallan su aplicación en seres humanos, modelos murinos y experimentos in vitro. Se tomaron en cuenta las condiciones del ambiente espacial como microgravedad y radiación que producen considerables cambios fisiológicos en el sistema cardiovascular (redistribución de líquidos, remodelación cardiovascular, arritmias); nervioso (sensitivomotores, neurosensoriales, neurovestibulares); respiratorio (cambios de volúmenes y capacidades); renal (litiasis); musculoesquelético (atrofia muscular, osteoporosis); hematológico (anemia); inmunológico (desregulación inmune) y digestivo (alteración de la microbiota intestinal). Además, existen procesos biológicos, moleculares y genéticos aún por explorar, para conocer y mitigar los mecanismos inciertos desencadenados en ambientes extremos y peligrosos. Por lo tanto, es una prioridad desarrollar e implementar contramedidas para reducir los efectos nocivos en la salud, con el objetivo de garantizar la adaptación, seguridad y performance del astronauta durante futuros viajes espaciales.

This Review Article is presented based on current scientific evidence on space medicine focused on human physiology and its countermeasures. Therefore, a non-systematic bibliographic search of scientific articles and research books in English-Spanish of the last 7 years was carried out, detailing their application in humans, murine models and in vitro experiments. The conditions of the space environment such as microgravity and radiation that produce considerable physiological changes in the cardiovascular system (redistribution of fluids, cardiovascular remodeling, arrhythmias) were taken into account; nervous (sensorimotor, neurosensory, neurovestibular); respiratory (volume and capacity changes); renal (lithiasis); musculoskeletal (muscular atrophy, osteoporosis); hematological (anemia); immunological (immune dysregulation) and digestive (intestinal microbiota disorder). In addition, there are biological, molecular and genetic processes still to be explored, in order to know and mitigate the uncertain mechanisms triggered in extreme and dangerous environments. Therefore, it is a priority to develop and implement countermeasures to reduce the harmful effects on health, with the aim of guaranteeing the astronaut's adaptation, safety and performance during future space flights.

Dynamic cerebral autoregulation after confinement in an isolated environment for 14 days

BACKGROUND@#To develop human space exploration, it is necessary to study the effects of an isolated and confined environment, as well as a microgravity environment, on cerebral circulation. However, no studies on cerebral circulation in an isolated and confined environment have been reported. Therefore, we investigated the effects of a 14-day period of confinement in an isolated environment on dynamic cerebral autoregulation.@*METHODS@#We participated in an isolation and confinement experiment conducted by the Japan Aerospace Exploration Agency in 2016. Eight healthy males were isolated and confined in a facility for 14 days. Data were collected on the days immediately before and after confinement. Arterial blood pressure waveforms were obtained using a finger blood pressure monitor, and cerebral blood flow velocity waveforms in the middle cerebral artery were obtained using transcranial Doppler ultrasonography for 6 min during quiet rest in a supine position. Dynamic cerebral autoregulation was evaluated by transfer function analysis between spontaneous variability of beat-to-beat mean arterial blood pressure and mean cerebral blood flow velocity.@*RESULTS@#Transfer function gain in the low- and high-frequency ranges increased significantly (0.54 ± 0.07 to 0.69 ± 0.09 cm/s/mmHg and 0.80 ± 0.05 to 0.92 ± 0.09 cm/s/mmHg, respectively) after the confinement.@*CONCLUSION@#The increases observed in transfer function gain may be interpreted as indicating less suppressive capability against transmission from arterial blood pressure oscillation to cerebral blood flow velocity fluctuation. These results suggest that confinement in an isolated environment for 14 days may impair dynamic cerebral autoregulation.@*TRIAL REGISTRATION@#UMIN000020703 , Registered 2016/01/22.

Tecnología espacial aplicada a la salud / The application of spatial technology in the health

Resumen La medicina espacial es la práctica de la medicina aplicada en el ser humano en el espacio exterior, incluyendo también el uso de la ciencia y tecnología para la prevención o el control de la exposición a los peligros que pueden causar problemas a la salud. El desarrollo de estas actividades repercute en la implementáción de nuevos instrumentos, tratamientos y aditamentos que propician un beneficio en la salud de to dos los que habitamos este planeta. En este artículo se verá como la inversión en ciencia y tecnología espacial repercute de manera directa e indirecta en beneficios para la salud en tierra. Todo lo que pasa o pasó en el universo impacta en la salud. La tecnología desarrollada para los vuelos espaciales ha traído grandes avances en esta materia, pero también en nuestro estilo de vida. Beneficios que propicia la inversión en esta rama, tanto en lo económico, lo social, y sobre todo en el tema de la salud humana.

Abstract Space medicine is the practice of Medicine applied to humans in outer space, including the use of science and technology for the prevention and control of hazards that could cause health problems. The development of these activities affects the implementation of new instruments, treatments and supplies that promote health benefits to all who inhabit this planet. This article reviews how the investment in space science and technology impacts on direct and indirect health benefits to Earth life. Everything that happens or has happened in the universe impacts our health. The technology developed for spaceflight has brought great advances in healthcare, but also in our lifestyle. These benefits bring investment in this area, both economically and socially, espedaily on human health.

Aerospace medicine

This paper presented briefly the different areas of discipline in aviation medicine and space medicine. The importance of having a basic knowledge in aviation medicine among the students, general medical practitioners and other personnel who have something to do with the equipment and aircraft design and manufacture is discussed. The presentation of the subject of space medicine touched only the well-known highlights of the present knowledge of the properties of space and the different problems that concern the human factor in manned space flights. (Summary)

A Space Medicine Course in an Undergraduate Curriculum of a Medical School / 医学教育

Because the environment of space is extremely harsh, manned space activities require considerable medical support. Space medicine, a field of medical science, deals with such situations. In this report, we present the outline of a space medicine course that we have established as an elective course in the School of Medicine, the University of Tsukuba, Japan. The students' responses to questionnaires indicated the popularity of the course and their interest in it. Concentrated courses are effective for teaching new cross-disciplinary areas in medical school.