Spaceflight Environment

The safety and health of individuals who may be exposed to the spaceflight environment are first and foremost cared for through prevention. This environment, which encompasses microgravity, radiation, and alternobaric factors, can have physiologic impacts on every human system. Available medical care and resources in the spaceflight environment are currently limited by mass and volume constraints, with available medical resources thereby focusing on a patient's stabilization and evacuation. An understanding of the spaceflight environment and its possible effects is crucial for the treatment of individuals prior to, during, and after spaceflight.

Treadmill exercise promotes bone tissue recovery in rats subjected to high + Gz loads

INTRODUCTION

High + Gz loads, the gravitational forces experienced by the body in hypergravity environments, can lead to bone loss in pilots and astronauts, posing significant health risks.

MATERIALS AND METHODS

To explore the effect of treadmill exercise on bone tissue recovery, a study was conducted on 72 male Wistar rats. These rats were subjected to four weeks of varying levels of periodic high + Gz loads (1G, 8G, 20G) experiments, and were subsequently divided into the treadmill group and the control group. The treadmill group underwent a continuous two-week treadmill experiment, while the control group rested during this period. The mechanical properties, microstructure, and molecular markers of their tibial bone tissue were measured using three-point bending, micro-CT, and PCR.

RESULTS

The results showed that treadmill exercise improved the elastic modulus, ultimate deflection, and ultimate load of rat bone tissue. It also increased the number, density, and volume fraction of bone trabeculae, and decreased their separation. Moreover, treadmill exercise enhanced osteogenesis and inhibited osteoclastogenesis.

CONCLUSION

This study demonstrates that treadmill exercise can promote the recovery of bone tissue in rats subjected to high + Gz loads, providing a potential countermeasure for bone loss in pilots and astronauts.

Assessment of transparency indicators in space medicine

Space medicine is a vital discipline with often time-intensive and costly projects and constrained opportunities for studying various elements such as space missions, astronauts, and simulated environments. Moreover, private interests gain increasing influence in this discipline. In scientific disciplines with these features, transparent and rigorous methods are essential. Here, we undertook an evaluation of transparency indicators in publications within the field of space medicine. A meta-epidemiological assessment of PubMed Central Open Access (PMC OA) eligible articles within the field of space medicine was performed for prevalence of code sharing, data sharing, pre-registration, conflicts of interest, and funding. Text mining was performed with the rtransparent text mining algorithms with manual validation of 200 random articles to obtain corrected estimates. Across 1215 included articles, 39 (3%) shared code, 258 (21%) shared data, 10 (1%) were registered, 110 (90%) contained a conflict-of-interest statement, and 1141 (93%) included a funding statement. After manual validation, the corrected estimates for code sharing, data sharing, and registration were 5%, 27%, and 1%, respectively. Data sharing was 32% when limited to original articles and highest in space/parabolic flights (46%). Overall, across space medicine we observed modest rates of data sharing, rare sharing of code and almost non-existent protocol registration. Enhancing transparency in space medicine research is imperative for safeguarding its scientific rigor and reproducibility.

[ENT in zero g: the cosmic challenges of otolaryngology]

Manned spaceflight places special demands on the human body, including the organs in the ENT region. These organs play a critical role in maintaining the health and safety of astronauts in space. In this paper, we review common ENT problems of spaceflight, including upper airway edema, middle ear and mastoid effusions, hearing loss, and dizziness with nausea. We discuss the underlying mechanisms contributing to these complaints, their clinical manifestations, and potential treatment strategies. In addition, we examine the potential impact of these conditions on astronaut health and mission outcomes. Finally, we emphasize the importance of preventive measures and future research in this area to optimize astronaut health and safety on future missions.

Hypergravity stimulates mechanical behavior and micro-architecture of tibia in rats

INTRODUCTION

The bone tissue is susceptible to hypergravity (+ G) environment. It is necessary to discuss the extent to which specific + G values are beneficial or detrimental to bone tissue. The objective of this study was to characterize the effects of high + G values on mechanical properties, microstructures, and cellular metabolism of bone.

MATERIALS AND METHODS

30 male Wistar rats aged 12 weeks were randomly divided into 5 groups, and bore different + G (namely + 1G, + 4G, + 8G, + 10G and + 12G) environments respectively for 4 weeks, 5 days each week, and 3 minutes each day. The macro-mechanical parameters, microstructure parameters, and mRNA transcription levels of the tibia were determined through the three-point bending method, micro-CT detection, and q-PCR analysis, respectively.

RESULTS

As the + G value increases, hypergravity becomes increasingly detrimental to the macro-mechanical performance of rat tibia. Concerning the microstructure of cancellous bone, there appears to be a favorable trend at + 4G, followed by a progressively detrimental trend at higher G values. In addition, the mRNA transcription levels of OPG and RANKL show an initial tendency of enhanced bone absorption at +4G, followed by an increase in bone remodeling capacity as G value increases.

CONCLUSION

The higher G values correspond to poorer macro-mechanical properties of the tibia, and a + 4G environment benefits the microstructure of the tibia. At the cellular level, bone resorption is enhanced in the + 4G group, but the bone remodeling capability gradually increases with further increments in G values.

Oral Health in Zero Gravity: A Comprehensive Review of Orofacial Effects and Countermeasures in Spaceflights

Space is a complex and challenging setting encompassing the region beyond Earth's atmosphere where astronauts and spacecraft operate. The unique conditions of spaceflights, particularly microgravity and radiation, pose significant challenges to astronaut health, including the orofacial region. It has effects on saliva production, microbial composition, and oral hygiene practices, which influence oral health status, such as increased risk of dental caries, gum diseases, oral discomfort, temporomandibular joint dysfunctions, sialoliths, pain and dysesthesia in the teeth and oral mucosa, masticatory muscle atrophy, and oral cancer which can be detrimental during prolonged missions. Hence, a comprehensive approach to dental care in space is imperative to ensure astronauts' well-being and overall health as we strive to extend our presence beyond Earth. This literature review paper sheds light on the intricate effects of space on the orofacial region and delves into the unique challenges astronauts face in upholding optimal oral health while in space. It explores the current state of dentistry in space and discusses advancements and strategies that aim to maintain optimal oral health for astronauts during extended space missions.

The Final Frontier: Palliative Care in Space is an Inevitability

As space exploration becomes increasingly common, palliative care for astronauts will require greater consideration. All aspects of palliative care need to be specifically adapted for astronauts. For example, addressing additional circumstances such as inability to see loved ones from Earth will be an important part of meeting their psychological and spiritual needs. A different approach to pharmacological management of end-of-life symptoms is also warranted due to changes in human physiology and pharmacokinetics in space.

Evaluation of free-floating tracheal intubation in weightlessness via ice-pick position with a direct laryngoscopy and classic approach with indirect videolaryngoscopy

Long duration spaceflights to the Moon or Mars are at risk for emergency medical events. Managing a hypoxemic distress and performing an advanced airway procedure such as oro-tracheal intubation may be complicated under weightlessness due to ergonomic constraints. An emergency free-floating intubation would be dangerous because of high failure rates due to stabilization issues that prohibits its implementation in a space environment. Nevertheless, we hypothesized that two configurations could lead to a high first-pass success score for intubation performed by a free-floating operator. In a non-randomized, controlled, cross-over simulation study during a parabolic flight campaign, we evaluated and compared the intubation performance of free-floating trained operators, using either a conventional direct laryngoscope in an ice-pick position or an indirect laryngoscopy with a video-laryngoscope in a classic position at the head of a high-fidelity simulation manikin, in weightlessness and in normogravity. Neither of the two tested conditions reached the minimal terrestrial ILCOR recommendations (95% first-pass success) and therefore could not be recommended for general implementation under weightlessness conditions. Free-floating video laryngoscopy at the head of the manikin had a significant better success score than conventional direct laryngoscopy in an ice-pick position. Our results, combined with the preexisting literature, emphasis the difficulties of performing oro-tracheal intubation, even for experts using modern airway devices, under postural instability in weightlessness. ClinicalTrials registration number NCT05303948.

Simulated Microgravity-Induced Changes to Drug Response in Cancer Cells Quantified Using Fluorescence Morphometry

Unlike plants that have special gravity-sensing cells, such special cells in animals are yet to be discovered. However, microgravity, the condition of apparent weightlessness, causes bone, muscular and immune system dysfunctions in astronauts following spaceflights. Decades of investigations show correlations between these organ and system-level dysfunctions with changes induced at the cellular level both by simulated microgravity as well as microgravity conditions in outer space. Changes in single bone, muscle and immune cells include morphological abnormalities, altered gene expression, protein expression, metabolic pathways and signaling pathways. These suggest that human cells mount some response to microgravity. However, the implications of such adjustments on many cellular functions and responses are not clear. Here, we addressed the question whether microgravity induces alterations to drug response in cancer cells. We used both adherent cancer cells (T98G) and cancer cells in suspension (K562) to confirm the known effects of simulated microgravity and then treated the K562 cells with common cancer drugs (hydroxyurea and paclitaxel) following 48 h of exposure to simulated microgravity via a NASA-developed rotary cell culture system. Through fluorescence-guided morphometry, we found that microgravity abolished a significant reduction (p < 0.01) in the nuclear-to-cytoplasm ratio of cancer cells treated with hydroxyurea. Our results call for more studies on the impact of microgravity on cellular drug response, in light of the growing need for space medicine, as space exploration grows.

Artificial Intelligence Applications in Space Medicine

INTRODUCTION:During future interplanetary space missions, a number of health conditions may arise, owing to the hostile environment of space and the myriad of stressors experienced by the crew. When managing these conditions, crews will be required to make accurate, timely clinical decisions at a high level of autonomy, as telecommunication delays and increasing distances restrict real-time support from the ground. On Earth, artificial intelligence (AI) has proven successful in healthcare, augmenting expert clinical decision-making or enhancing medical knowledge where it is lacking. Similarly, deploying AI tools in the context of a space mission could improve crew self-reliance and healthcare delivery.METHODS: We conducted a narrative review to discuss existing AI applications that could improve the prevention, recognition, evaluation, and management of the most mission-critical conditions, including psychological and mental health, acute radiation sickness, surgical emergencies, spaceflight-associated neuro-ocular syndrome, infections, and cardiovascular deconditioning.RESULTS: Some examples of the applications we identified include AI chatbots designed to prevent and mitigate psychological and mental health conditions, automated medical imaging analysis, and closed-loop systems for hemodynamic optimization. We also discuss at length gaps in current technologies, as well as the key challenges and limitations of developing and deploying AI for space medicine to inform future research and innovation. Indeed, shifts in patient cohorts, space-induced physiological changes, limited size and breadth of space biomedical datasets, and changes in disease characteristics may render the models invalid when transferred from ground settings into space.Cheung HC, De Louche C, Komorowski M. Artificial intelligence applications in space medicine. Aerosp Med Hum Perform. 2023; 94(8):610-622.

Effects of simulated microgravity and vibration on osteoblast and osteoclast activity in cultured zebrafish scales

Zebrafish cultured scales have been used effectively to study cellular and molecular responses of bone cells. In order to expose zebrafish scales to simulated microgravity (SMG) and/or vibration, we first determined via apoptosis staining whether cells of the scale survive in culture for two days and hence, we restricted our analyses to two-day durations. Next, we measured the effects of SMG and vibration on cell death, osteoclast tartrate-resistant acid phosphatase, and osteoblast alkaline phosphatase activity and on the number of Runx2a positive cells. We found that during the SMG treatment, osteoclast tartrate-resistant acid phosphatase activity increased on average, while the number of Runx2a positive cells decreased significantly. In contrast, SMG exposure caused a decrease in osteoblast activity. The vibration treatment showed an increase, on average, in the osteoblast alkaline phosphatase activity. This study demonstrates the effect of SMG and vibration on zebrafish scales and the effects of SMG on bone cells. We also show that zebrafish scales can be used to examine the effects of SMG on bone maintenance.

Response of cardiac pulse parameters in humans at various inclinations via 360° rotating platform for simulated microgravity perspective

On the Earth, the human body is designed and adapted to function under uniform gravitational acceleration. However, exposure to microgravity or weightlessness as experienced by astronauts in space causes significant alterations in the functioning of the human cardiovascular system. Due to limitations in using real microgravity platforms, researchers opted for various ground-based microgravity analogs including head-down tilt (HDT) at fixed inclination. However, in the present study, an investigation of response of various cardiac parameters and their circulatory adaptation in 18 healthy male subjects was undertaken by using an indigenously developed 360° rotating platform. Cardiac pulse was recorded from 0° to 360° in steps of 30° inclination using piezoelectric pulse sensor (MLT1010) and associated cardiac parameters were analyzed. The results showed significant changes in the pulse shape while an interesting oscillating pattern was observed in associated cardiac parameters when rotated from 0° to 360°. The response of cardiac parameters became normal after returning to supine posture indicating the ability of the cardiovascular system to reversibly adapt to the postural changes. The observed changes in cardiac parameters at an inclination of 270°, in particular, were found to be comparable with spaceflight studies. Based on the obtained results and the proposed extended version of fluid redistribution mechanism, we herewith hypothesize that the rotation of a subject to head down tilt inclination (270°) along with other inclinations could represent a better microgravity analog for understanding the cumulative cardiac response of astronauts in space, particularly for short duration space missions.

Surgery in the Next Space Missions

In the coming years, missions to the Moon and Mars shall be the new goals of space flight. The complexity of these missions due to the great distance from Earth and the unforeseen obstacles to settle on another planet have given rise to great concerns for crew health and survival. The need for advanced crew autonomy and a different approach to surgical emergency require new protocols and devices to help future crew medical officers and other crew members in a task of unprecedented difficulty. Hence, the increasing variety of schedules, devices, and protocols being developed. A serious health problem, such as an emerging surgical disease or severe trauma, can jeopardize the mission and survival of the entire crew. Many other difficulties are present in deep-space missions or settlements on other planets, such as communication and supply, also medical, delays, and shortage, and the presence of radiation. Progress in advanced technologies as well as the evolution of robotic surgery and the use of artificial intelligence are other topics of this review. In this particular area of research, even if we are still very far from an "intelligent robot", this evolution must be evaluated in the light of legislative and ethical considerations. This topic was presented at the annual meeting of the American College of Surgeons-Italy Chapter in 2021.

Medical Astro-Microbiology: Current Role and Future Challenges

The second and third decades of the twenty-first century are marked by a flourishing of space technology which may soon realise human aspirations of a permanent multiplanetary presence. The prevention, control and management of infection with microbial pathogens is likely to play a key role in how successful human space aspirations will become. This review considers the emerging field of medical astro-microbiology. It examines the current evidence regarding the risk of infection during spaceflight via host susceptibility, alterations to the host's microbiome as well as exposure to other crew members and spacecraft's microbiomes. It also considers the relevance of the hygiene hypothesis in this regard. It then reviews the current evidence related to infection risk associated with microbial adaptability in spaceflight conditions. There is a particular focus on the International Space Station (ISS), as one of the only two  crewed objects in low Earth orbit. It discusses the effects of spaceflight related stressors on viruses and the infection risks associated with latent viral reactivation and increased viral shedding during spaceflight. It then examines the effects of the same stressors on bacteria, particularly in relation to changes in virulence and drug resistance. It also considers our current understanding of fungal adaptability in spaceflight. The global public health and environmental risks associated with a possible re-introduction to Earth of invasive species are also briefly discussed. Finally, this review examines the largely unknown microbiology and infection implications of celestial body habitation with an emphasis placed on Mars. Overall, this review summarises much of our current understanding of medical astro-microbiology and identifies significant knowledge gaps.

Graphical Abstract

Novel 3-D Printable Aspiration Device "SPUTA VACUUMER" Designed to Minimize Invasion

Goal: The purpose of this study is to develop a minimally invasive sputum aspiration device. Methods: The current general method is to insert a suction catheter into the trachea. However, sufficient suction cannot be obtained unless the catheter reaches the target. A new connection device "SPUTA VACUUMER" has been invented. The effectiveness of the SPUTA VACUUMER is tested in this study. Results: After manually inflating the lungs, the device applies suction pressure to the entire lungs. Peripheral sputum or foreign matter is effectively moved to the upper respiratory tract. Conclusions: "SPUTA VACUUMER" is minimally invasive, simple and cost effective. The device can be manufactured with a 3D printer and the plastic injection molding model received pharmaceutical approval in Japan in 2021. It is currently being used in clinical settings. It can be operated by non-skilled personnel and may be performed in space and improve astronauts' quality of life.

Evolving radiological protection guidelines for exploration-class missions

International Space Station partner nations have yet to agree on career radiation dose constraints. This is of increasing concern for collaborative mission planning beyond low-Earth orbit, since it is likely that one or two long-duration missions will expose crew to a cumulative dose that approaches or exceeds their current respective limits. As with radiological effects, the cumulative health impact of the numerous other injuries and illnesses documented during spaceflight is inherently heightened with longer and farther missions, say to the Moon and Mars. This paper summarizes the origin of existing radiological constraints employed by the Canadian Space Agency and explores how to build upon these protection practices to address the challenges associated with beyond low-Earth orbit missions. The discussion then leads into a review of conventional risk metrics currently under evaluation by space-faring nations to quantify risk of radiation-induced cancer mortality. This paper concludes with a proposal for the application of an existing burden of disease model termed the Disability Adjusted Life Year, to space exploration. This model can accommodate the many health hazards of spaceflight, including ionizing radiation, on a common scale. It has the potential to serve as an intuitive communication tool for informing on the impact of spaceflight on crew health.

To infinity and beyond: Strategies for fabricating medicines in outer space

Recent advancements in next generation spacecrafts have reignited public excitement over life beyond Earth. However, to safeguard the health and safety of humans in the hostile environment of space, innovation in pharmaceutical manufacturing and drug delivery deserves urgent attention. In this review/commentary, the current state of medicines provision in space is explored, accompanied by a forward look on the future of pharmaceutical manufacturing in outer space. The hazards associated with spaceflight, and their corresponding medical problems, are first briefly discussed. Subsequently, the infeasibility of present-day medicines provision systems for supporting deep space exploration is examined. The existing knowledge gaps on the altered clinical effects of medicines in space are evaluated, and suggestions are provided on how clinical trials in space might be conducted. An envisioned model of on-site production and delivery of medicines in space is proposed, referencing emerging technologies (e.g. Chemputing, synthetic biology, and 3D printing) being developed on Earth that may be adapted for extra-terrestrial use. This review concludes with a critical analysis on the regulatory considerations necessary to facilitate the adoption of these technologies and proposes a framework by which these may be enforced. In doing so, this commentary aims to instigate discussions on the pharmaceutical needs of deep space exploration, and strategies on how these may be met.

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Space is a hostile environment that threatens human health and drug stability.

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Data on the behaviour of medicines in space is critical but lacking.

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Novel drug manufacturing and delivery strategies are needed to safeguard crewmembers’ safety.

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Chemputing, synthetic biology, and 3D printing are examples of such emerging technologies.

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A regulatory framework for space medicines must be implemented to assure quality.

Changes in dietary habits and eating behaviors during COVID-19 induced confinement: A study from Jordan

Objective

This study aimed to evaluate dietary habits (DH) and eating behaviors (EB) among adults during confinement induced by COVID-19 in Jordan.

Method

In this cross-sectional study, an online survey designed to assess the change in DH and EB during April and May 2020 was distributed using various social media platforms.

Results

The survey was completed by a total of 1844 adult (18-72 years) participants from the public in Jordan. The results indicated an increase (42.5-61.8%) in most of the DH and EB examined in the current study in the majority of participants. Among these changes, they have increased (p < 0.05) the prevalence of fruit and vegetable, immune boosters, water, and hot beverage consumption, as well as decreased (p < 0.05) eating in restaurants and fatty food consumption, indicating a positive change. Conversely, a larger (p < 0.05) proportion of participants reported increased consumption of high-calorie food and late-night eating, indicating a risky behavior for obesity and subsequent chronic complications. Additionally, age, sex, obesity, education, income, and type of job appeared to contribute (p < 0.05) to changes in DH and EB. Overall, confinement caused by COVID-19 appears to compel adults to adopt a specific DH and EB. Although most of these changes were positive, some were negative.

Conclusion

This study provides essential information for designing subpopulation recommendations and developmental programs for adults under such conditions.

Effectiveness of CPR in Hypogravity Conditions-A Systematic Review

(1) Background: Cardiopulmonary resuscitation (CPR), as a form of basic life support, is critical for maintaining cardiac and cerebral perfusion during cardiac arrest, a medical condition with high expected mortality. Current guidelines emphasize the importance of rapid recognition and prompt initiation of high-quality CPR, including appropriate cardiac compression depth and rate. As space agencies plan missions to the Moon or even to explore Mars, the duration of missions will increase and with it the chance of life-threatening conditions requiring CPR. The objective of this review was to examine the effectiveness and feasibility of chest compressions as part of CPR following current terrestrial guidelines under hypogravity conditions such as those encountered on planetary or lunar surfaces; (2) Methods: A systematic literature search was conducted by two independent reviewers (PubMed, Cochrane Register of Controlled Trials, ResearchGate, National Aeronautics and Space Administration (NASA)). Only controlled trials conducting CPR following guidelines from 2010 and after with advised compression depths of 50 mm and above were included; (3) Results: Four different publications were identified. All studies examined CPR feasibility in 0.38 G simulating the gravitational force on Mars. Two studies also simulated hypogravity on the Moon with a force of 0.17 G/0,16 G. All CPR protocols consisted of chest compressions only without ventilation. A compression rate above 100/s could be maintained in all studies and hypogravity conditions. Two studies showed a significant reduction of compression depth in 0.38 G (-7.2 mm/-8.71 mm) and 0.17 G (-12.6 mm/-9.85 mm), respectively, with nearly similar heart rates, compared to 1 G conditions. In the other two studies, participants with higher body weight could maintain a nearly adequate mean depth while effort measured by heart rate (+23/+13.85 bpm) and VO_2max (+5.4 mL·kg^-1·min^-1) increased significantly; (4) Conclusions: Adequate CPR quality in hypogravity can only be achieved under increased physical stress to compensate for functional weight loss. Without this extra effort, the depth of compression quickly falls below the guideline level, especially for light-weight rescuers. This means faster fatigue during resuscitation and the need for more frequent changes of the resuscitator than advised in terrestrial guidelines. Alternative techniques in the straddling position should be further investigated in hypogravity.

Skin Microbial Changes during Space Flights: A Systematic Review

Background. Sixty years after the launch of the first human into space, different studies on the physiological changes that humans undergo during dynamic flight phases and prolonged weightlessness have been undertaken. Understanding these changes is important for the creation of the preventative measures that are essential to ensuring astronaut health. Among these changes, those of the skin are frequent, despite being rarely treated during missions. The skin is a physical barrier that protects the body from pathogen invasion and environmental changes, and it harbors diverse microbial communities that form the skin microbiota. Methods. A systematic literature review of skin microbiome changes during space flight was conducted using public electronic databases (PubMed and Scopus) selecting studies published from 2015 to 2022. The systematic review was performed according to 2020 PRISMA guidelines. Results. A total of 17 studies were collected and, after screening for inclusion and exclusion criteria, eight studies were included in this review. According to the examined literature, some skin microbiota changes seems to be only temporary, in particular Gamma- and Betaproteobacteria abundance tends to decrease, while the occurrence of the Malassezia species and Firmicutes, including Staphylococcus and Streptococcus, tends to increase. At the same time, there seems to be an exchange of microorganisms between astronauts and between the confined environment and a single astronaut, with alterations in the proportion of microorganisms maintained during the flight, in particular for species such as Corynebacterium spp., Staphylococcus spp., Streptococcus spp. and Cloacibacterium spp. Given that skin contributes both to protecting the body from pathogen invasion and environmental changes and to maintaining human homeostasis, changes in the skin microbiota of astronauts might result in skin diseases. Discussion. The skin microbiota of astronauts seems to influence the microbial composition of the International Space Station, but further studies should be performed to better understand skin microbiota dynamics and to prevent the development of dermatologic conditions during space flight.

Space Medicines for Space Health

Scientists from around the world are studying the effects of microgravity and cosmic radiation via the "off-Earth" International Space Station (ISS) laboratory platform. The ISS has helped scientists make discoveries that go beyond the basic understanding of Earth. Over 300 medical experiments have been performed to date, with the goal of extending the knowledge gained for the benefit of humanity. This paper gives an overview of these numerous space medical findings, critically identifies challenges and gaps, and puts the achievements into perspective toward long-term space traveling and also adding benefits to our home planet. The medical contents are trifold structured, starting with the well-being of space travelers (astronaut health studies), followed by medical formulation research under space conditions, and then concluding with a blueprint for space pharmaceutical manufacturing. The review covers essential elements of our Earth-based pharmaceutical research such as drug discovery, drug and formulation stability, drug-organ interaction, drug disintegration/bioavailability/pharmacokinetics, pathogen virulence, genome mutation, and body's resistance. The information compiles clinical, medicinal, biological, and chemical research as well as fundamentals and practical applications.

Space Medicine: Inspiring a new generation of physicians

Space medicine is critical in enabling safe human exploration of space. The discipline focuses on supporting human survival, health, and performance in the austere environment of space. It is set to grow ever more important as significant transitions in the standard of space operations in the suborbital, low earth orbit (LEO) and beyond LEO domains will take place in the coming years. NASA along with their international and commercial partners have committed to returning to the Moon through the Artemis missions in this decade with the aim of achieving a permanent sustainable human presence on the lunar surface. Additionally, the development of reusable rockets is set to increase the number and frequency of humans going to space by making space travel more accessible. Commercial spaceflight and missions beyond LEO present many new challenges which space medicine physicians and researchers will need to address. Space medicine operates at the frontier of exploration, engineering, science and medicine. Aviation and Space Medicine (ASM) is the latest specialty to be recognised by the Royal College of Physicians and the General Medical Council in the UK. In this paper, we provide an introduction to space medicine, review the effects of spaceflight on human physiology and health along with countermeasures, medical and surgical issues in space, the varied roles of the ASM physician, challenges to UK space medicine practice and related research, and finally we explore the current representation of space medicine within the undergraduate curriculum.

Gravitational Dose‐Response Curves for Acute Cardiovascular Hemodynamics and Autonomic Responses in a Tilt Paradigm

Background

The cardiovascular system is strongly dependent on the gravitational environment. Gravitational changes cause mechanical fluid shifts and, in turn, autonomic effectors influence systemic circulation and cardiac control. We implemented a tilt paradigm to (1) investigate the acute hemodynamic response across a range of directions of the gravitational vector, and (2) to generate specific dose‐response relationships of this gravitational dependency.

Methods and Results

Twelve male subjects were tilted from 45° head‐up tilt to 45° head‐down tilt in 15° increments, in both supine and prone postures. We measured the steady‐state hemodynamic response in a range of variables including heart rate, stroke volume, cardiac output, oxygen consumption, total peripheral resistance, blood pressure, and autonomic indices derived from heart rate variability analysis. There is a strong gravitational dependence in almost all variables considered, with the exception of oxygen consumption, whereas systolic blood pressure remained controlled to within ≈3% across the tilt range. Hemodynamic responses are primarily driven by differential loading on the baroreflex receptors, combined with differences in venous return to the heart. Thorax compression in the prone position leads to reduced venous return and increased sympathetic nervous activity, raising heart rate, and systemic vascular resistance while lowering cardiac output and stroke volume.

Conclusions

Gravitational dose‐response curves generated from these data provide a comprehensive baseline from which to assess the efficacy of potential spaceflight countermeasures. Results also assist clinical management of terrestrial surgery in prone posture or head‐down tilt positions.

Facing Trauma and Surgical Emergency in Space: Hemorrhagic Shock

Although the risk of trauma in space is low, unpredictable events can occur that may require surgical treatment. Hemorrhage can be a life-threatening condition while traveling to another planet and after landing on it. These exploration missions call for a different approach than rapid return to Earth, which is the policy currently adopted on the International Space Station (ISS) in low Earth orbit (LEO). Consequences are difficult to predict, given the still scarce knowledge of human physiology in such environments. Blood loss in space can deplete the affected astronaut’s physiological reserves and all stored crew supplies. In this review, we will describe different aspects of hemorrhage in space, and by comparison with terrestrial conditions, the possible solutions to be adopted, and the current state of the art.

Running Experimental Research of a Cable-Driven Astronaut on-Orbit Physical Exercise Equipment

Manned spaceflight has already become an important approach to space science exploration, while long-term exposure to the microgravity environment will lead to severe health problems for astronauts, including bone loss, muscle atrophy, and cardiovascular function decline. In order to mitigate or eliminate those negative influences, this paper presents a cable-driven exercise equipment that can be applied in a microgravity environment to render multi-functional on-orbit physical exercise modes for astronauts. First, the structure of cable module and the configuration of the equipment were proposed. Second, a two-level controller was provided, including the cable tension distribution algorithm and tension controller of the cable module. A safety protection strategy was proposed to ensure the safety of the astronaut. Furthermore, simulation and running experiment studies of the equipment were conducted, the results demonstrate that the load force of the equipment could achieve a high-level accuracy, and the exercise status of the astronaut could be monitored and protected in the meantime. Therefore, physical exercises could be carried out by the assistance of the equipment to keep astronauts in good shape on-orbit.

The Future of Personalized Medicine in Space: From Observations to Countermeasures

The aim of personalized medicine is to detach from a “one-size fits all approach” and improve patient health by individualization to achieve the best outcomes in disease prevention, diagnosis and treatment. Technological advances in sequencing, improved knowledge of omics, integration with bioinformatics and new in vitro testing formats, have enabled personalized medicine to become a reality. Individual variation in response to environmental factors can affect susceptibility to disease and response to treatments. Space travel exposes humans to environmental stressors that lead to physiological adaptations, from altered cell behavior to abnormal tissue responses, including immune system impairment. In the context of human space flight research, human health studies have shown a significant inter-individual variability in response to space analogue conditions. A substantial degree of variability has been noticed in response to medications (from both an efficacy and toxicity perspective) as well as in susceptibility to damage from radiation exposure and in physiological changes such as loss of bone mineral density and muscle mass in response to deconditioning. At present, personalized medicine for astronauts is limited. With the advent of longer duration missions beyond low Earth orbit, it is imperative that space agencies adopt a personalized strategy for each astronaut, starting from pre-emptive personalized pre-clinical approaches through to individualized countermeasures to minimize harmful physiological changes and find targeted treatment for disease. Advances in space medicine can also be translated to terrestrial applications, and vice versa. This review places the astronaut at the center of personalized medicine, will appraise existing evidence and future preclinical tools as well as clinical, ethical and legal considerations for future space travel.

Robot-assisted surgery in space: pros and cons. A review from the surgeon's point of view

The target of human flight in space has changed from permanence on the International Space Station to missions beyond low earth orbit and the Lunar Gateway for deep space exploration and Missions to Mars. Several conditions affecting space missions had to be considered: for example the effect of weightlessness and radiations on the human body, behavioral health decrements or communication latency, and consumable resupply. Telemedicine and telerobotic applications, robot-assisted surgery with some hints on experimental surgical procedures carried out in previous missions, had to be considered as well. The need for greater crew autonomy in health issues is related to the increasing severity of medical and surgical interventions that could occur in these missions, and the presence of a highly trained surgeon on board would be recommended. A surgical robot could be a valuable aid but only inasfar as it is provided with multiple functions, including the capability to perform certain procedures autonomously. Space missions in deep space or on other planets present new challenges for crew health. Providing a multi-function surgical robot is the new frontier. Research in this field shall be paving the way for the development of new structured plans for human health in space, as well as providing new suggestions for clinical applications on Earth.

Oh G: The x, y and z of human physiological responses to acceleration

NEW FINDINGS

What is the topic of this review? This review focuses on the main physiological challenges associated with exposure to acceleration in the Gx, Gy and Gz directions and to microgravity. What advances does it highlight? Our current understanding of the physiology of these environments and latest strategies to protect against them are discussed in light of the limited knowledge we have in some of these areas.

ABSTRACT

The desire to go higher, faster and further has taken us to environments where the accelerations placed on our bodies far exceed or are much lower than that attributable to Earth's gravity. While on the ground, racing drivers of the fastest cars are exposed to high degrees of lateral acceleration (Gy) during cornering. In the air, while within the confines of the lower reaches of Earth's atmosphere, fast jet pilots are routinely exposed to high levels of acceleration in the head-foot direction (Gz). During launch and re-entry of suborbital and orbital spacecraft, astronauts and spaceflight participants are exposed to high levels of chest-back acceleration (Gx), whereas once in space the effects of gravity are all but removed (termed microgravity, μG). Each of these environments has profound effects on the homeostatic mechanisms within the body and can have a serious impact, not only for those with underlying pathology but also for healthy individuals. This review provides an overview of the main challenges associated with these environments and our current understanding of the physiological and pathophysiological adaptations to them. Where relevant, protection strategies are discussed, with the implications of our future exposure to these environments also being considered.

Effects of long-term immobilisation on endomysium of the soleus muscle in humans

NEW FINDINGS

What is the central question of this study? While muscle fibre atrophy in response to immobilisation has been extensively examined, intramuscular connective tissue, particularly endomysium, has been largely neglected: does endomysium content of the soleus muscle increase during bed rest? What is the main finding and its importance? Absolute endomysium content did not change, and previous studies reporting an increase are explicable by muscle fibre atrophy. It must be expected that even a relative connective tissue accumulation will lead to an increase in muscle stiffness.

ABSTRACT

Muscle fibres atrophy during conditions of disuse. Whilst animal data suggest an increase in endomysium content with disuse, that information is not available for humans. We hypothesised that endomysium content increases during immobilisation. To test this hypothesis, biopsy samples of the soleus muscle obtained from 21 volunteers who underwent 60 days of bed rest were analysed using immunofluorescence-labelled laminin γ-1 to delineate individual muscle fibres as well as the endomysium space. The endomysium-to-fibre-area ratio (EFAr, as a percentage) was assessed as a measure related to stiffness, and the endomysium-to-fibre-number ratio (EFNr) was calculated to determine whether any increase in EFAr was absolute, or could be attributed to muscle fibre shrinkage. As expected, we found muscle fibre atrophy (P = 0.0031) that amounted to shrinkage by 16.6% (SD 28.2%) on day 55 of bed rest. ENAr increased on day 55 of bed rest (P < 0.001). However, when analysing EFNr, no effect of bed rest was found (P = 0.62). These results demonstrate that an increase in EFAr is likely to be a direct effect of muscle fibre atrophy. Based on the assumption that the total number of muscle fibres remains unchanged during 55 days of bed rest, this implies that the absolute amount of connective tissue in the soleus muscle remained unchanged. The increased relative endomysium content, however, could be functionally related to an increase in muscle stiffness.

End-Effector Contact and Force Detection for Miniature Autonomous Robots Performing Lunar and Expeditionary Surgery

INTRODUCTION

The U.S. Space Force was stood up on December 20, 2019 as an independent branch under the Air Force consisting of about 16,000 active duty and civilian personnel focused singularly on space. In addition to the Space Force, the plans by NASA and private industry for exploration-class long-duration missions to the moon, near-earth asteroids, and Mars makes semi-independent medical capability in space a priority. Current practice for space-based medicine is limited and relies on a "life-raft" scenario for emergencies. Discussions by working groups on military space-based medicine include placing a Role III equivalent facility in a lunar surface station. Surgical capability is a key requirement for that facility.

MATERIALS AND METHODS

To prepare for the eventuality of surgery in space, it is necessary to develop low-mass, low power, mini-surgical robots, which could serve as a celestial replacement for existing terrestrial robots. The current study focused on developing semi-autonomous capability in surgical robotics, specifically related to task automation. Two categories for end-effector tissue interaction were developed: Visual feedback from the robot to detect tissue contact, and motor current waveform measurements to detect contact force.

RESULTS

Using a pixel-to-pixel deep neural network to train, we were able to achieve an accuracy of nearly 90% for contact/no-contact detection. Large torques were predicted well by a trained long short-term memory recursive network, but the technique did not predict small torques well.

CONCLUSION

Surgical capability on long-duration missions will require human/machine teaming with semi-autonomous surgical robots. Our existing small, lightweight, low-power miniature robots perform multiple essential tasks in one design including hemostasis, fluid management, suturing for traumatic wounds, and are fully insertable for internal surgical procedures. To prepare for the inevitable eventuality of an emergency surgery in space, it is essential that automated surgical robot capabilities be developed.

Repetitive Transcranial Magnetic Stimulation (rTMS) Improves the Gait Disorders of Rats Under Simulated Microgravity Conditions Associated With the Regulation of Motor Cortex

In previous studies, it has been proved that repetitive transcranial magnetic stimulation (rTMS) improves dyskinesia induced by conditions such as spinal cord injury, Parkinson diseases and cerebral ischemia. However, it is still unknown whether it can be used as a countermeasure for gait disorders in astronauts during space flight. In this study, we evaluated the effects of rTMS on the rat gait function under simulated microgravity (SM) conditions. The SM procedure continued for consecutive 21 days in male Wistar rats. Meanwhile, the high-frequency rTMS (10 Hz) was applied for 14 days from the eighth day of SM procedure. The behavioral results showed that SM could cause gait disorders such as decreased walking ability and contralateral limb imbalance in rats, which could be reversed by rTMS. Furthermore, rTMS affected the neural oscillations of motor cortex, enhancing in δ (2–4 Hz) band, suppressing in θ (4–7 Hz), and α (7–12 Hz) bands. Additionally, rTMS could activate mTOR in the motor cortex. These data suggests that the improvement effects of rTMS on gait disorders in rats under SM conditions might be associated with its regulation on neural oscillations in the cerebral motor cortex and the expression of some motor-related proteins which may enhance the control of nervous system on muscle function. Based on our results, rTMS can be used as an potential effective supplement in the field of clinical and rehabilitation research to reduce gait disorders caused by the space environment.

Effect of corneal refractive surgery on accommodative and binocular dysfunctions among civilian pilots in Southwest China

Background

To analyze whether corneal refractive surgery (CRS) is associated with the distribution of different accommodative dysfunctions (ADs) and binocular dysfunctions (BDs) in civilian pilots. A further aim was to analyze the percentages and visual symptoms associated with ADs and/or BDs in this population.

Methods

One hundred and eight civilian pilots who underwent CRS from January 2001 to July 2012 (age: 30.33 ± 4.60 years) were enrolled, the mean preoperative SE was − 1.51 ± 1.15 D (range: − 1.00- − 5.00 D). Ninety-nine emmetropic civilian pilots (age: 29.64 ± 3.77 years) who were age- and sex-matched to the CRS group were also enrolled. Refractive status, accommodative and binocular tests of each subject were performed. Visually related symptoms were quantified using the 19-item College of Optometrists in Vision Development Quality of Life (COVD-QOL) questionnaire. The 19 items were summed to obtain visual symptom scores that might indicate visual dysfunctions. The chi-square test was used to analyze differences in percentages of ADs and/or BDs between the CRS and emmetropic groups. The Mann-Whitney U test was used to compare visual symptom scores between pilots with ADs and/or BDs and pilots with normal binocular vision.

Results

No significant difference was observed between the CRS and emmetropic groups in the overall prevalence of ADs and BDs (15.7% and 15.2% in the CRS and emmetropic groups, respectively; P = 0.185). ADs were present in 4.63% and 3.03% of the CRS and emmetropic group, respectively. BDs were observed in 11.1% and 12.1% of the CRS and emmetropic group, respectively, yielding no significant differences between the groups in the prevalence of ADs or BDs (AD: P = 0.094; BD: P = 0.105). Pilots with ADs and/or BDs had significantly more visual symptoms than pilots with normal binocular vision (p < 0.001).

Conclusions

CRS for civilian pilots with low-moderate myopia might not impact binocular functions. ADs and/or BDs commonly occur in both emmetropia pilots and pilots who undergo CRS, and pilots with ADs and/or BDs are associated with increased symptoms. This study confirms the importance of a full assessment of binocular visual functions in detecting and remedying these dysfunctions in this specific population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-01855-0.

Temporal Characteristics of the Oropharyngeal and Nasal Microbiota Structure in Crewmembers Stayed 180 Days in the Controlled Ecological Life Support System

Confined experiments are carried out to simulate the closed environment of space capsule on the ground. The Chinese Controlled Ecological Life Support System (CELSS) is designed including a closed-loop system supporting 4 healthy volunteers surviving for 180 days, and we aim to reveal the temporal characteristics of the oropharyngeal and nasal microbiota structure in crewmembers stayed 180 days in the CELSS, so as to accumulate the information about microbiota balance associated with respiratory health for estimating health risk in future spaceflight. We investigated the distribution of microorganisms and their dynamic characteristics in the nasal cavity and oropharynx of occupants with prolonged confinement. Based on the 16S rDNA v3–v4 regions using Illumina high-throughput sequencing technology, the oropharyngeal and nasal microbiota were monitored at eight time points during confinement. There were significant differences between oropharyngeal and nasal microbiota, and there were also individual differences among the same site of different volunteers. Analysis on the structure of the microbiota showed that, in the phylum taxon, the nasal bacteria mainly belonged to Actinobacteria, Firmicutes, Proteobacteria, Bacteroidetes, etc. In addition to the above phyla, in oropharyngeal bacteria Fusobacterial accounted for a relatively high proportion. In the genus taxon, the nasal and oropharyngeal bacteria were independent. Corynebacterium and Staphylococcus were dominant in nasal cavity, and Corynebacterium, Streptococcus, and Neisseria were dominant in oropharynx. With the extension of the confinement time, the abundance of Staphylococcus in the nasal cavity and Neisseria in the oropharynx increased, and the index Chao fluctuated greatly from 30 to 90 days after the volunteers entered the CELSS.

Conclusion: The structure and diversity of the nasal and oropharyngeal microbiota changed in the CELSS, and there was the phenomenon of migration between occupants, suggesting that the microbiota structure and health of the respiratory tract could be affected by living in a closed environment for a long time.

Aerospace Implications of Key Neurological Conditions

INTRODUCTION: The neurological impact (or lack thereof) of certain medical histories and imaging findings is important to understand in the context of air and spaceflight. There are a number of neurological conditions that, if present in pilots and astronauts, carry variable (and sometimes adverse) functional implications for safety and overall mission success. In this systematic overview, the authors will refer to the relevant clinical and radiological features of brain tumors and vascular anomalies, cerebral edema and intracranial hypertension, concussion and the traumatic brain injury (TBI) spectrum, hematomas, cerebrospinal fluid circulation anomalies including hydrocephalus and sequestrations, spinal degenerative changes, and cerebral ischemia and demyelination. It is notable that these last two conditions have recently been reported to be a complication in some people with coronavirus disease 2019 (COVID-19). A paradigm for practical neurological workup of symptomatic pilots and astronauts will be discussed, as will the controversial notion of pre-emptive radiological screening (vs. not screening) in asymptomatic or clinically occult situations. The concepts of medical surveillance in the setting of known or diagnosed pathologies, and expert panel review and simulator and flight checks in complex neurological cases, are also elaborated on in this paper. We believe this overview will contribute toward the enhancement of a broad understanding of neurological conditions, their clinical workup, and their precautionary management in the setting of aviation and aerospace.Khurana VG, Jithoo R, Barnett M. Aerospace implications of key neurological conditions. Aerosp Med Hum Perform. 2021; 92(2):113119.

Calculation of dose distribution in a realistic brain structure and the indication of space radiation influence on human brains

One of the most important steps in the near-future space age will be a crew mission returning to the Moon and even a manned mission to Mars. Unfortunately, such a mission will expose astronauts to unavoidable cosmic radiation in deep space and on the Martian or lunar surface. Thus, a better understanding of the radiation environment for such a mission and the consequent biological impacts on humans, in particular the human brains, is critical. The need for this better understanding is strongly suggested by investigations on animal models and on human patients who were undergoing irradiation for cancer therapy in the head. These have revealed unexpected alterations in the central nervous system behavior and sensitivity of mature neurons in the brain to charged particles. However, such experiments shall not be carried out realistically in space using humans. Therefore, to investigate the impact of cosmic radiation on human brains and the potential influence on the brain functions, we model and study the cosmic particle-induced radiation dose in a realistic head structure. Specifically speaking, 134 slices of computed tomography (CT) images of an actual human head have been used as a 3D phantom in Geant4 (GEometry ANd Tracking), which is a Monte Carlo tool for simulating energetic particles impinging into different parts of the brain and deliver radiation dose therein. As a first step, we compare the influence of different brain structures (e.g., with or without bones, with or without soft tissues) to the resulting dose therein to demonstrate the necessity of using a realistic brain structure for our investigation. Afterward, we calculate energy-dependent functions of dose distribution, for the most important (some of the most abundant and most biologically-relevant) particle types encountered during a deep space mission inside a spacecraft or habitat such as protons, helium ions, neutrons and some major heavier ions like carbon, nitrogen, and iron particles. Furthermore, two different scenarios have been modeled as a comparison: a human head without shielding protection and a human head with an aluminum shielding shell around (of varying thickness). These functions can then be used to fold with energetic cosmic-ray particle spectra of the ambient environment for obtaining the dose rate distribution at different lobes of the human brain. Our calculation of these functions can serve as a ready tool and a baseline for further evaluations of the radiation in the brain encountered during a space mission with different radiation fields, such as on the surface of the Moon or Mars.

Changes in Physical Activity and Sedentary Behavior Amid Confinement: The BKSQ-COVID-19 Project

BACKGROUND

Coronavirus disease 19 (COVID-19) has compelled implementing confinement measure across the globe. These measures can potentially lead to many changes in lifestyle. However, no studies examined the effect of COVID-19-induced confinement on physical activity (PA) and sedentary behavior (SB).

METHODS

During April and May of 2020, the current study surveyed changes in PA and SB induced by COVID-19 confinement.

RESULTS

The participants of the study were 1844. Among the participants who were regularly involved in PA, the majority (41.8-42.2%) of the participants reported a "decrease" (p<0.05) in walking, jogging, and sports while the majority (46.3-53.1%) reported a "no change" (p<0.05) in swimming, cycling, and weight lifting. With regard to the SB, most of the participants reported an "increase" in watching TV (72.3%), using electronics (82.7%), and logging to social media (81.9%). Additionally, gender, job type, obesity, and being worried to contract the disease were associated (p<0.05) with changes in PA. On the other hand, age, gender, obesity, job type and income were related (p<0.05) to changes in SB.

CONCLUSION

Results of the current study might enhance knowledge about the impact of COVID-19 on lifestyle, particularly PA and SB. Subsequently, it can also be used to establish strategies to enhance engagement in activities during the current and future pandemics.

Progress in research of digestive system trauma and stress injury under microgravity environment

The last two decades have witnessed the rapid develop-ment of China's manned spaceflight industry. Studies have showed that the weightlessness environment has a series of adverse effects on the human body. Due to the complexity of the structure and function of the digestive system, the impact of weightlessness on the digestive system has certain particularity. How to ensure the steady state of the digestive system during astronaut's space mission and in the training under simulated weightlessness needs to be studied urgently. This review focuses on the progress in the research of digestive system trauma, stress injury, and repair under microgravity environment.

Resuscitation and Evacuation from Low Earth Orbit: A Systematic Review

INTRODUCTION

Provision of critical care and resuscitation was not practical during early missions into space. Given likely advancements in commercial spaceflight and increased human presence in low Earth orbit (LEO) in the coming decades, development of these capabilities should be considered as the likelihood of emergent medical evacuation increases.

METHODS

PubMed, Web of Science, Google Scholar, National Aeronautics and Space Administration (NASA) Technical Server, and Defense Technical Information Center were searched from inception to December 2018. Articles specifically addressing critical care and resuscitation during emergency medical evacuation from LEO were selected. Evidence was graded using Oxford Centre for Evidence-Based Medicine guidelines.

RESULTS

The search resulted in 109 articles included in the review with a total of 2,177 subjects. There were two Level I systematic reviews, 33 Level II prospective studies with 647 subjects, seven Level III retrospective studies with 1,455 subjects, and two Level IV case series with four subjects. There were two Level V case reports and 63 pertinent review articles.

DISCUSSION

The development of a medical evacuation capability is an important consideration for future missions. This review revealed potential hurdles in the design of a dedicated LEO evacuation spacecraft. The ability to provide critical care and resuscitation during transport is likely to be limited by mass, volume, cost, and re-entry forces. Stabilization and treatment of the patient should be performed prior to departure, if possible, and emphasis should be on a rapid and safe return to Earth for definitive care.

Medications in Space: In Search of a Pharmacologist's Guide to the Galaxy

Medications have been used during space missions for more than half a century, yet our understanding of the effects of spaceflight on drug pharmacokinetics and pharmacodynamics is poor. The space environment induces time-dependent alterations in human physiology that include fluid shifts, cardiovascular deconditioning, bone and muscle density loss, and impaired immunity. This review presents the current knowledge on the physiological effects of spaceflight that can translate into altered drug disposition and activity and eventually to inadequate treatment. It describes findings from studies in astronauts along with mechanistic studies in animal models and in vitro systems. Future missions into deeper space and the emergence of commercial spaceflight will require a more detailed understanding of space pharmacology to optimize treatment in astronauts and space travelers.

Drug Interactions in Space: a Cause for Concern?

PURPOSE

Crewmembers aboard the International Space Station (ISS) have free access to an increasing number of medications within medical kits. The aim of the current study was to assess the number, severity and reliability of potential drug-drug interactions (DDIs) involving those medications.

METHODS

We evaluated the information obtained from clinical decision support systems. Searches for potential DDIs were applied to published lists of medications available to US astronauts in medical kits aboard the ISS.

RESULTS

A total of 311 potential DDIs were identified by Lexi-Interact, of which approximately half were recognized by Micromedex as well. Major, moderate and minor interactions consisted 23.5%, 68.5% and 8.0% of entries, respectively. The reliability of 71.1% of alerts was fair. Commonly used drugs, including zolpidem and zaleplon, were involved in multiple potential interactions that were classified as major based on additive CNS depression.

CONCLUSIONS

Most potential DDIs likely to be encountered in space are unestablished even in terrestrial medicine and their assignment is based on class-effects. Yet, some drug combinations may be associated with clinically-relevant consequences. Future DDI rating should be adjusted to space-related outcomes. Until that happens, it would be advisable to avoid non-established drug combinations in space when possible.

Passive force control of multimodal astronaut training robot

For the purpose of solving the problem of astronaut training in weightlessness environment, this article proposes a multimodal astronaut training robot to enable astronauts to perform running, bench press and deep squat training in the weightless environment, so as to help them mitigate the adverse effects brought by the space adaptation syndrome. Taking the modularized wire driving unit as the research object, the dynamic model of the passive force servo system was established; and the passive force control strategy was designed. The experimental results show that the system is of good stability, high steady-state accuracy, and excellent dynamic quality after correction. When the given signal frequency is 10 Hz, the system phase lag is about 9°, and the loading error is about 5%. The passive force servo control strategy can effectively reduce the surplus force. When the speed disturbance frequency of carrying unit is within 3 Hz, the elimination rate of the surplus force can reach 90%.

Space Medicine Requirements open to Innovation in Biomedical Engineering

The International Space Medicine Summit II sought to identify mature data with significant clinical implications for Terrestrial populations. This work aims at identifying innovation in biomedical engineering (BE), involving space medicine and translation.

METHODS

Following PRISMA Guidelines, we sought to review the published literature and NASA technical resources (from 2012 to 2017) to identify space medical technology which has been translated for use by private costumers.

RESULTS

The analysis focuses on technical and medical requirements, human health and Terrestrial implication.

DISCUSSION

Innovation in BE arises from matching space medical requirements for developing autonomous medical systems.

SIGNIFICANCE

Highlighting the use and benefits of aerospace medical research for Terrestrial medical care.