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Antonsen, Erik

Publications and source records attributed to Antonsen, Erik.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2019

Communication Bandwidth Considerations for Exploration Medical Care During Space Missions

Destinations beyond low Earth orbit, especially Mars, have several important constraints, including limited resupply, limited to no possibility of medical evacuation, and delayed communication with ground support teams. Therefore, medical care is driven towards greater autonomy and necessitates a medical system that supports this paradigm, including the potential for high medical data transfer rates in order to share medical information and coordinate care with the ground in an intermittent fashion as communication allows. The medical data transfer needs for a Martian exploration mission were estimated by defining two medical scenarios that would require high data rate communications between the spacecraft and Earth. One medical scenario involves a case of hydronephrosis (outflow obstruction of the kidney) that evolves into pyelonephritis (kidney infection), then urosepsis (systemic infection originating from the kidney), due to obstruction by a kidney stone. A second medical scenario involved the death of a crewmember’s child back on Earth that requires behavioral health care. For each of these scenarios, a data communications timeline was created following the medical care described by the scenario. From these timelines, total medical data transfers and burst transmission rates were estimated. Total data transferred from the vehicle-to-ground were estimated to be 94 gigabytes (GB) and 835 GB for the hydronephrosis and behavioral health scenarios, respectively. Data burst rates were estimated to be 7.7 megabytes per second (MB/s) and 15 MB/s for the hydronephrosis and behavioral health scenarios, respectively. Even though any crewed Mars mission should be capable of functioning autonomously, as long as the possibility of communication between Earth and Mars exists, Earth-based subject matter experts will be relied upon to augment mission medical capability. Therefore, setting an upper boundary limit for medical communication rates can help factor medical system needs into total vehicle communication requirements.

Krihak, Michael↗
NASA NTRS2019

Development of an Accepted Medical Condition List for Exploration Medical Capability Scoping

The Accepted Medical Conditions List (AMCL) is a product designed to provide a traceable, repeatable, evidence-based consensus process for scoping the medical capability needs for future design reference missions (DRMs) and upcoming programs. These include a Mars transit DRM and a shorter duration cis-lunar DRM. The development of a baseline AMCL by the Exploration Medical Capability (ExMC) Element will assist the effort to identify high priority medical capabilities for inclusion in mission and vehicle planning and provide traceable and documented clinical needs to the Systems Engineering teams tasked with requirements development and design work.

Medical Condition List↗
NASA NTRS2019

ExMC Approach to Pharmaceutical Stability Research: An Overview

Goals of Stability Studies: Identify medications that are stable under real and simulated space conditions, especially deep space radiation; Identify medications that are potent and safe after their expiration dates; Ultimately provide a safe and effective formulary for exploratory spaceflight missions. ExMC: Exploration Medical Capabilities.

Cory, Wendy↗
NASA NTRS2018

Medical Simulations for Exploration Medicine

Medical simulation is a useful tool that can be used to train personnel, develop medical processes, and assist cross-disciplinary communication. Medical simulations have been used in the past at NASA for these purposes, however they are usually created ad hoc. A stepwise approach to scenario development has not previously been used. The NASA Exploration Medical Capability (ExMC) created a medical scenario development tool to test medical procedures, technologies, concepts of operation and for use in systems engineering (SE) processes.

Reyes, David↗
NASA NTRS2018

Challenges in Clinical Management of Radiation-Induced Illnesses in Exploration Spaceflight

Historical solar particle events (SPEs) provide context for some understanding of acute radiation exposure risk to astronauts traveling outside of low Earth orbit. Modeling of potential doses delivered to exploration crewmembers anticipates limited radiation-induced health impacts, including prodromal symptoms of nausea, emesis, and fatigue, but suggests that more severe clinical manifestations are unlikely. Recent large animal-model research in space-analogs closely mimicking SPEs has identified coagulopathic events independent of the hematopoietic sequelae of higher radiation doses, similar in manifestation to disseminated intravascular coagulation (DIC). We explored the challenges of clinical management of radiation-related clinical manifestations, using currently accepted modeling techniques and anticipated physiological sequelae, to identify medical capabilities needed to successfully manage SPE-induced radiation illnesses during exploration spaceflight.

Blue, Rebecca↗
NASA NTRS2017

Medical Systems Engineering to Support Mars Mission Crew Autonomy

Human spaceflight missions to Mars face exceptionally challenging resource limitations that far exceed those faced before. Increasing transit times, decreasing opportunity for resupply, communications challenges, and extended time to evacuate a crew to definitive medical care dictate a level of crew autonomy in medical care that is beyond the current medical model. To approach this challenge, a medical systems engineering approach is proposed that relies on a clearly articulated Concept of Operations and risk analysis tools that are in development at NASA. This paper proposes an operational clinical model with key terminology and concepts translated to a controls theory paradigm to frame a common language between clinical and engineering teams. This common language will be used for design and validation of an exploration medical system that is fully integrated into a Mars transit vehicle. This approach merges medical simulation, human factors evaluation techniques, and human-in-the-loop testing in ground based analogs to tie medical hardware and software subsystem performance and overall medical system functionality to metrics of operational medical autonomy. Merging increases in operational clinical autonomy with a more restricted vehicle system resource scenario in interplanetary spaceflight will require an unprecedented level of medical and engineering integration. Full integration of medical capabilities into a Mars vehicle system may require a new approach to integrating medical system design and operations into the vehicle Program structure. Prior to the standing-up of a Mars Mission Program, proof of concept is proposed through the Human Research Program.

Antonsen, Erik↗
NASA NTRS2017

Programmatic Considerations to Reduce the Risk of Adverse Renal Stone Events in Spaceflight

Introduction: Microgravity exposure may alter the likelihood that astronauts will experience renal stones. The potential risk includes both acute and chronic health issues, with the potential for significant impact on mission objectives. Methods: To understand the role of the NASA's Human Research Program (HRP) research agenda in both preventing and addressing renal stones in spaceflight, current astronaut epidemiologic data and a summary of programmatic considerations are reviewed. Results: Although there has never been a symptomatic renal stone event in a U.S. crewmember during spaceflight, urine chemistry has been altered - likely due to induced changes in renal physiology as a result of exposure to microgravity. This may predispose astronauts to stone formation, leading the HRP to conduct and sponsor research to: 1) understand the risk of stone formation in space; 2) prevent stones from forming; and 3) address stones that may form by providing novel diagnostic and therapeutic approaches. Discussion: The development of a renal stone during spaceflight is a significant medical concern that requires the HRP to minimize this risk by providing the ability to prevent, diagnose, monitor and treat the condition during spaceflight. A discussion of the risk as NASA understands it is followed by an overview of the multiple mitigations currently under study, including novel ultrasound techniques for stone detection and manipulation, and how they may function as part of a larger exploration medical system.

Antonsen, Erik↗
NASA NTRS2017

A Quantitative Risk-Benefit Analysis of Prophylactic Surgery Prior to Extended-Duration Spaceflight

INTRODUCTION: Among otherwise healthy astronauts undertaking deep space missions, the risks for acute appendicitis (AA) and cholecystitis (AC) are not zero. If these conditions were to occur during spaceflight they may require surgery for definitive care. The proposed study quantifies and compares the risks of developing de novo AA and AC in-flight to the surgical risks of prophylactic laparoscopic appendectomy (LA) and cholecystectomy (LC) using NASA's Integrated Medical Model (IMM). METHODS: The IMM is a Monte Carlo simulation that forecasts medical events during spaceflight missions and estimates the impact of these medical events on crew health. In this study, four Design Reference Missions (DRMs) were created to assess the probability of an astronaut developing in-flight small-bowel obstruction (SBO) following prophylactic 1) LA, 2) LC, 3) LA and LC, or 4) neither surgery (SR# S-20160407-351). Model inputs were drawn from a large, population-based 2011 Swedish study that examined the incidence and risks of post-operative SBO over a 5-year follow-up period. The study group included 1,152 patients who underwent LA, and 16,371 who underwent LC. RESULTS: Preliminary results indicate that prophylactic LA may yield higher mission risks than the control DRM. Complete analyses are pending and will be subsequently available. DISCUSSION: The risk versus benefits of prophylactic surgery in astronauts to decrease the probability of acute surgical events during spaceflight has only been qualitatively examined in prior studies. Within the assumptions and limitations of the IMM, this work provides the first quantitative guidance that has previously been lacking to this important question for future deep space exploration missions.

Carroll, Danielle↗
NASA NTRS2017

NASA Health and Human Performance in Spaceflight

NASA, because of its mission and history, has tended to be an insular organization dominated by traditional engineering. Because of the engineering problems associated with early space endeavors, the historical approach to solving problems has been that of engineering. Long duration space travel will require a different approach, one requiring wider participation of those with expertise in divergent, emerging, and evolving fields. NASA has only recently begun to recognize this insufficiency and to reach out to communities, both domestic and international, to gain expertise on how to remedy it.

Antonsen, Erik↗