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All sourcesNASA NTRSDOE OSTI
NASA NTRS2020

Automated Cardiovascular Pathology Assessment using Semantic Segmentation and Ensemble Learning

Cardiac magnetic resonance imaging provides high spatial resolution, enabling improved extraction of important functional and morphological features for cardiovascular disease staging. Segmentation of ventricular cavities and myocardium in cardiac cine sequencing provides a basis to quantify cardiac measures such as ejection fraction. A method is presented that curtails the expense and observer bias of manual cardiac evaluation by combining semantic segmentation and disease classification into a fully automatic processing pipeline. The initial processing element consists of a robust dilated convolutional neural network architecture for voxel-wise segmentation of the myocardium and ventricular cavities. The resulting comprehensive volumetric feature matrix captures diagnostic clinical procedure data and is utilized by the final processing element to model a cardiac pathology classifier. Our approach evaluated anonymized cardiac images from a training data set of 100 patients (4 pathology groups, 1 healthy group, 20 patients per group) examined at the University Hospital of Dijon. The top average Dice index scores achieved were 0.940, 0.886, 0.849 for structure segmentation of the left ventricle (LV), myocardium and right ventricle (RV) respectively. A 5-ary pathology classification accuracy of 90% was recorded on an independent test set using the trained model. Performance results demonstrate potential for advanced machine learning methods to deliver accurate, efficient and reproducible cardiac pathological assessment.

Semantic Segmentation↗
NASA NTRS2018

Automated Semantic Segmentation for Volumetric Cardiovascular Feature Quantification and Pathology Assessment

We present a pipeline method that curtails the expense and observer bias of manual cardiac evaluation by combining semantic segmentation and disease classification as a fully automatic processing pipeline. The initial element consists of a 2D U-Net convolutional neural network architecture for voxel-wise segmentation of the myocardium and ventricular cavities. The results of the segmentation were used to compute a comprehensive volumetric feature matrix that captured diagnostic clinical procedure data and that was used to model a cardiac pathology classifier.Our approach evaluated anonymized parasternal MRI cardiac images from a database of 100 patients (4 pathology groups, 1 healthy group, 20 patients per group) examined at the University Hospital of Dijon. We achieved top average Dice index scores of 0.939, 0.849, 0.886 for structure segmentation of the left ventricle (LV), right ventricle (RV) and myocardium respectively. A 5-ary pathology classification accuracy of 90% was recorded on an independent test set using our trained model.

Lindsey, Tony↗
NASA NTRSDate not supplied

Spaceflight Medical Evacuation Risk Assessment Principles - A Qualitative Investigation

BACKGROUND Future human space exploration beyond Low Earth Orbit (LEO) will require innovative solutions in many areas, primarily those that provide direct medical support to crew on long-duration missions and optimize their health and performance. The associated challenges therein will be numerous, including but not necessarily limited to extended one-way or "asynchronous" communication delays, minimal to non-existent resupply, and a prolonged transit time to "definitive care" ranging from 3-days to 9-months. At the same time, long-duration exploration spacecraft and crew will face restrictions on mass, power, volume, and data far more significant than that seen in current LEO settings. Given these limitations, medical risk assessment is of primary importance, especially evaluating the implications of a medical evacuation of an ill or injured crewmember. Such evacuations are complicated, potentially dangerous, and well may be impossible in certain phases of the mission. Regardless, such issues must be weighed against the risks of the injured crew remaining aboard a spacecraft with limited medical resources. OBJECTIVE This qualitative study drew from the experiences of subject matter experts (SMEs) in spaceflight and appropriate analog environments (i.e., military, disaster, and extreme environment fields) to identify unique principles common amongst medical evacuation considerations helpful in informing future risk assessment tools. Appropriate analog environments included austere operational settings where multiple factors (weather, logistics/limited resupply, denied/extreme environments, and patient condition) resulted in a limited ability to provide definitive local medical care. The fundamental principles in question revolved around scenarios where evacuation became a complicating yet necessary consideration and where life-threatening medical concerns had to be weighed against critical mission objective(s). The primary authors collected semi-structured data gathered through in-depth interviews with 16 subject matter experts (SMEs). Interview questions investigated how these SMEs consider and weigh the attendant risks present in medical evacuation scenarios. Among the critical questions posed were those that sought to understand how the SME balanced the challenges and requirements of medical evacuation (or keeping an injured patient "on-site" aka: "prolonged field care") against the evacuation operation's risks on impacting overarching mission success. The team analyzed interview transcripts for common themes and principles using the qualitative methods of thematic analysis based on consensus, co-occurrence, and comparison. As a result, nine primary risk consideration themes and nine contributing factor themes emerged, all of which will ideally inform future medical evacuation decision-making tools and operational decision-making for exploration class missions. Specific aims for this study included: 1. Identification of common principles used to assess risks and benefits of medical evacuations in extreme environments 2. Identification of common points of friction or complication and challenges in extreme environment evacuations

A T Almand↗
NASA NTRSDate not supplied

One-Carbon Metabolism and SANS 2022 Update

Spaceflight Associated Neuro-ocular Syndrome, or SANS, affects a subset of astronauts (1, 2), and biochemical evidence has documented differences in those astronauts (3). Specifically, they had higher circulating concentrations of metabolites of the one-carbon metabolic pathway (1C), including homocysteine, and these concentrations were higher before flight (3). After ruling out many potential confounding factors in these otherwise healthy individuals (e.g., sex, kidney function, vitamin status, coffee consumption), a study of genetics was warranted. In an initial pilot effort, we documented a genetic predisposition to develop ophthalmic changes after long-duration space flight (4). That is, from a limited study of 5 single-nucleotide polymorphisms (SNPs), we found that the G allele for the MTRR A66G SNP was associated with a greater risk of choroidal folds and cotton-wool spots after flight, and the C allele for SHMT1 C1420T was protective against optic disc edema (4). These data provide a potential pathway for understanding why some individuals develop SANS, while others do not. The initial pilot study of 5 SNPs yielded striking findings, but the 1C pathway is far more complex. An effort was undertaken to examine more than 500 1C SNPs to see if a broader examination could help illuminate this association. That work is ongoing. The astronaut findings led us to advocate for the inclusion of 1C pathway genetic and biochemistry testing on other SANS-related projects, noting that genetics might help identify responders, non-responders, or outliers. The first such effort yielded evidence of an association of specific forms of the MTRR and SHMT-1 SNPs and vitamin B12 status with end-tidal CO2 after acute carbon dioxide exposure (5). The second such effort led to the identification that individuals exposed to strict head-down tilt and CO2 for 30-d who developed optic disc edema also had risk alleles for the two SNPs described above (6). Additionally, we identified a clinical population with many characteristics either attributed or purported to be involved in the ocular changes seen in affected astronauts: women with polycystic ovary syndrome (PCOS). PCOS is a condition of androgen excess and anovulatory menstrual cycles. The shared characteristics and clinical findings between SANS and PCOS generally include higher circulating homocysteine concentrations, increased retinal nerve fiber layer thickness, increased androgen concentrations (or responses), and altered carbohydrate metabolism. To our knowledge, no study has examined whether women with PCOS have asymptomatic ophthalmic anomalies observed in astronauts with SANS. While researchers have evaluated the one-carbon metabolism pathway polymorphisms of PCOS patients, and initial studies show an association with certain one-carbon polymorphisms, none have looked at the set of SNPs identified in our studies that are associated with ophthalmic changes in astronauts. Accordingly, we designed a study to evaluate the association of one-carbon pathway SNPs and ophthalmic findings in patients with PCOS and/or IIH compared to controls. Subjects provided blood samples for vitamin and one carbon biochemistry analyses, an extensive analysis of >500 SNPs associated with one carbon metabolism and had eye examinations and ocular imaging. Data analysis are underway. The data collected to date have shown associations between one carbon pathway biochemistry and genetics and incidence of SANS. The mechanisms for SANS has yet to be identified, although many hypotheses exist. Based on our data, we have developed (8, 9) and expanded (6) a multi-hit hypothesis for how these seemingly disparate findings could be linked. While intriguing, the hypothesis represents the starting point for further research. We aim to clarify the relationship between B-vitamin status and genetics with regard to the risk of SANS. Ultimately, understanding the mechanism(s) behind this will provide a means to predict, prevent, or treat these ophthalmologic pathologies in astronauts, and terrestrial populations.

S M Smith↗
NASA NTRS2023

Application of Bioengineering in Space Exploration - Sleep Study System

Bioengineering has spread roots far and wide among the needs of space exploration. The field creates many of paths to generate information from a variety of sources. One such source is the astronauts on the International Space Station (ISS). As of now the investigation is focused on the quality of sleep of crew members during a long duration flight. Our team is investing time into a piece of hardware’s comfort, waste, and operability. The hardware was not originally designed for space; therefore, the device must be modified to function at a optimal level in space. The design not made for space has generated some ailments, such as discomfort and decreased mobility. A function of the internship was to produce designs that would manage the wires to increase mobility and comfort. The wires excess slack was reduced by the part that was designed. The piece was adjustable, so the patient may adjust the system to their comfort and space compatible material was used. This product will help control the direction and length of the wires, thereby aiding in comforting the patient. This multifaceted design may be used in future for all other wire management for wearable biomedical sensor on orbit.

Biomedical↗
NASA NTRS2024

Flow Cytometry Methods to Monitor Immune System Dysregulation in Astronauts

Persistent immune system dysregulation has been documented to occur in astronauts participating in orbital spaceflight onboard the International Space Station. The phenomenon consists of reductions in T and NK cell function, altered cytokine profiles, persistent inflammation, and the subclinical reactivation of latent herpesviruses. In select crewmembers the dysregulation does actually lead to clinical symptoms, primarily atypical allergy or atopic dermatitis/zoster. Flow cytometry has served a central role defining the ‘immune assessment’ panel of assays that allow monitoring of astronauts. The cytometry assays which have been utilized include: 1. Peripheral leukocyte subsets 2. T cell function 3. Monocyte function 4. NK cell function 5. Intracellular cytokine analysis 6. Virus-specific T cell number (tetramer assay) 7. Virus-specific T cell function (peptide stimulation) 8. Leukocyte-bacterial challenge cytometry 9. Cytometric bead/multiplex array (soluble proteins) The use of these assays has been validated through various ISS flight investigations to define, to varying degrees, both in-flight, and post-flight immune system alterations. The kinetics of the dysregulation through the various phases of spaceflight, as well as post-flight recovery, have also been documented. To allow the science to occur within the orbital constraints of a spaceflight investigation, particular sample collection and processing techniques were developed compatible with the delays associated with terrestrial processing of in-flight samples. A subset of the assays has been adapted to routine monitoring of astronauts via a NASA ‘ISS Standard Measures’ activity, with the data from a specific crew then provided to all science investigators for that particular mission. This battery of cytometry assays has also been applied, through ground investigations, to several terrestrial ‘spaceflight analog’ populations. The purpose was to validate the analog which most closely replicates the in-flight observed pattern of alterations, generally believed to be winterover at an Antarctica station. To assist in determination of clinical risk, the assay panel has also been applied to investigations of various terrestrial patient populations, particularly zoster patients. As NASA is initiating crewed lunar missions via the ‘Artemis’ program, deployment of a miniaturized, microgravity-compatible flow cytometer, would be extremely beneficial to allow real time monitoring of crewmembers. Real time medical data could influence use of several countermeasures options during deep space missions. Several such instruments have been developed and validated to varying degrees of success. Assay details and summary findings across the various flight and ground platforms will be presented, as will current status in developing such technology for in-flight use.

Brian Crucian↗
NASA NTRSDate not supplied

Exploration Atmosphere Demonstration of A Multi-Functional Integrated Medical Device (Tempus Pro)

INTRODUCTION The Exploration Medical Capability (ExMC) element within the Human Research Program and the Exploration Medical Integrated Product Team (XMIPT) within the Mars Campaign Office seek to advance medical system design and risk-informed decision-making for exploration missions. This includes assessment of candidate devices and their compatibility within a variety of increasingly Earth-independent medical scenarios. The Tempus Pro (Remote Diagnostic Technologies, Ltd., Philips Corp., Farnborough, UK) is a commercial-off-the-shelf (COTS), multi-functional integrated medical device capable of vital signs monitoring, with built-in procedure support (iAssist), patient record and telemedicine communication features, and medical imaging (e.g., camera, laryngoscope, ultrasound) that meets multiple exploration medical capability needs. One of several hypobaric atmospheres being considered for exploration vehicles is 8.2 psi with 34% oxygen. To assess the useability of the Tempus Pro in such environments by individuals without formal medical training, the unit was tested in May and June of 2023 at the Johnson Space Center 20-Foot Exploration Atmosphere Chamber in conjunction with the Exploration Atmospheres-2 (EA-2) study. TECHNOLOGY DEMONSTRATION Eight subjects in the EA-2 study were assigned roles as the caregiver or patient – or both in the case of a self-exam – and caregivers were asked to place sensors for 3-Lead ECG, non-invasive blood pressure (NIBP), pulse oximetry (SpO2), and temperature using Tempus Pro’s iAssist. Depending on the procedure, additional tasks included an oropharyngeal exam of the throat with the laryngoscope and capturing ultrasound images of a cardiac subxiphoid view or of the user’s choice from a pre-specified list. Scenarios ranged from remote-guided to fully autonomous operations and surveyed the effectiveness of support, amount of support desired, and importance of support by type (e.g., written crew procedures, iAssist and device guidance, remote console guidance, etc.). Feedback from the subjects and the support personnel was also gathered to inform future designs for training and support and to determine what operations are plausible given different levels of each. An unweighted NASA task load index (TLX) was used to profile the demands of using the device, however the sample size does not support statistics. The research was exploratory in nature and qualitative information was the main goal. Calibration checks on the Tempus Pro were conducted before and after chamber testing to ensure the device was in useable condition. RESULTS All subjects performed their tasks successfully and found the Tempus Pro easy to use with the support provided. The calibration checks outside the chamber showed that the Tempus Pro remained unchanged and measurements inside the chamber were within normal values. Caregivers taking the NASA TLX reported mean scores ≤ 41/100 showing the tasks to be undemanding and less demanding with repeated use (~20/100). Novice users were able to easily connect sensors and take vital signs with the guidance from Tempus Pro’s iAssist feature. For more complex tasks, such as the oropharyngeal exam and ultrasound image acquisition, guidance beyond iAssist was needed, primarily from a supporting physician. Feedback on the importance of support types varied by person and scenario but greater than 50% of the support used by each was non-native to the device. Overall opinions were positive, but the ultrasound users expressed a lack of confidence in their results and 3 out of 4 desired more time, training, or support. Subjects found the sensors to be comfortable and comparable to prior experiences with such devices, except for the blood pressure cuff, which squeezed too tightly for uncomfortably long periods. Many observations provoked discussion, especially regarding ultrasound, that will aide decisions about future demonstrations.

R. S. Miller↗
NASA NTRS2025

Limitations and Feasibility of Mini X-Ray Devices in Space Environments

LIMITATIONS AND FEASIBILITY OF MINI X-RAY DEVICES IN SPACE ENVIRONMENTS As space exploration advances toward long-duration missions, reliable medical diagnostic tools become increasingly critical. The miniature x-ray (XR) technology demonstrations by the Exploration Medical Capability (ExMC) and the Exploration Medical Integrated Product Team (XMIPT) aim to assess the feasibility and utility of miniature XR devices in spaceflight. This abstract explores the limitations of current miniature XR systems, the challenges of training crew members, the potential role of clinical decision support systems (CDSS), and the feasibility of ground-based image interpretation. We also propose the integration of miniature XR into other ExMC efforts aimed at identifying the capabilities and resources needed for future exploration class missions. One of the primary challenges with miniature XR devices is the ability to achieve specific anatomical views, particularly in the confined and weightless conditions of a spacecraft. Operators may struggle to acquire diagnostic-quality images when space is limited for proper patient positioning and the volume of the imaging device. Since space radiation and detector limitations may further impact image quality, the flexibility of the operating procedures of these devices will be critical for their success in space applications. CHALLENGES IN TRAINING CREW TO OPERATE IMAGING DEVICES Training in the skills necessary to acquire diagnostic-quality scans may be a barrier for non-clinician crewmembers. The curriculum developed for crew medical officers (CMOs) will require simplification and adaptation to fit into the highly truncated pre-flight training period. Therefore, hands-on familiarization and simulation, both pre-flight and just-in-time training during missions, will be crucial to ensuring the crew can operate the devices in real-life situations. The ability to adjust acquisition parameters must be simplified or made automatic through exam selections on equipment user interfaces, and subject and operator positioning should be assisted with laser guidance and pictorial guides. POTENTIAL FOR CDSS OR ARTIFICIAL INTELLIGENCE (AI)-ASSISTED CDSS CDSS and AI-assisted CDSS offer significant promise in assisting crew members with limited medical training. These systems could provide real-time feedback on image quality and interpretation, helping to mitigate the risks of human error during space missions. Integrating procedural guidance tools, such as virtual and augmented reality, will support crewmembers in accurately positioning patients and obtaining high-quality images. However, the success of such systems will depend on the development of robust training datasets, integration with spaceflight-rated hardware, and the medical decision-making capabilities of operators. FEASIBILITY OF GROUND INTERPRETATION AND DATA TRANSMISSION Reliance on ground-based interpretation may prove difficult for acute care during exploration class-missions due to delays in transmission with increasing distance from Earth or complete communication blackout periods. In such instances where immediate interpretation for clinical intervention is required, crew must be able to interpret the images independently or utilize AI-based assistance to do so. File sizes for XR exams can also be large if numerous images are acquired and bandwidth constraints may limit data transmissions for both radiography and ultrasound exams. FUTURE WORK AND INTEGRATION INTO THE EVIDENCE LIBRARY Future work proposes integrating miniature XR devices into NASA’s Evidence Library to address medical conditions identified as significant contributors to crew morbidity and mortality. The possibility of combining miniature XR with other imaging modalities, such as ultrasound devices, is also under investigation. In conclusion, while miniature XR technology holds potential for extraterrestrial medical systems, there are significant challenges to overcome. Training, integration of AI tools, dedicated exam protocols for microgravity, and improved data transmission systems will be key to realizing the full benefits of miniature XR technology in space.

A M Nelson↗
NASA NTRS2025

Magnetic Resonance Imaging (MRI) to Assess Changes to Trabecular Microarchitecture (Trb µArch) of the Hip

BACKGROUND . Calculated loss rates in trabecular (Trb) volumetric bone mineral density (vBMD), in astronauts after return from 6-month long-duration (LD) spaceflight, are rapid relative to menopause-induced loss rates and could contribute to the observed lack of recovery. Perforations in the Trb bony struts, skeletal fragility and fractures [5] have been associated with the rapid rate of bone loss in women due to menopause. The more rapid loss rate observed in astronauts could be inducing similar, irreversible losses of trabecular connectivity as seen in cadaver studies of female skeletons. These changes are not detectable by DXA technology and would not be discovered in astronauts during scheduled, triennial DXA testing for primary osteoporosis. High-resolution-peripheral quantitative computed tomography (HR-pQCT) of the lower leg have detected losses in Trb vBMD (vBMD) and changes in Trb microarchitecture (µArch) in astronauts immediately following routine 6-month spaceflights and continuing in some individuals for 1 or more years postflight with no signs of recovery. Resolution of these microarchitectural changes by whole body QCT, especially in the deeply embedded hip bone, is prohibitive due to excessive and unsafe radiation exposures. While HR-pQCT has sufficient resolution to study Trb µArch at safe and lower radiation exposure testing is restricted only to the lower leg and wrist. Hence, a technology to detect detrimental changes to Trb µArch in astronauts, especially of the hip, is needed to inform type and timing of countermeasures to irreversible deficits (preflight, inflight and postflight). METHODS . This HRP-funded study (2023-2027) will verify the sensitivity of a protocol for MRI scanning (on a 3T Siemens Vida) to detect changes to hip Trb µArch in persons following spinal cord injury (SCI); skeletal immobilization below the spinal lesion will serve as an analog for non-weight-bearing during spaceflight. The study period has been extended by 1 yr due to delayed Richmond IRB approval in Y1. A 3T MRI protocol will characterize serial changes in hip Trb µArch in SCI patients from time of admission at the Richmond VA Medical Center to their scheduled annual exam 12-months later. SCI patients with age, sex, and physical characteristics like ISS astronauts will be consented. The ability of 3T MRI hip scan to discriminate loss of trabecular connectivity subjects with SCI will be compared to age- and sex-matched ambulatory controls. A comparison between HR-pQCT and MRI measurements at the ankle (distal tibia) of study subjects will also be performed. A modified DXA scan analysis (3D-Shaper) will also be verified as a potential method for monitoring concurrent changes in hip Trb bone over 12-month. SIGNIFICANCE . Deliverables: a surveillance method for assessing for irreversible losses of connectivity and how skeletal changes after LD spaceflight(s) would modify the terrestrial risk of primary osteoporosis.

Spinal Cord Injury↗
NASA NTRS2025

Magnetic Resonance Imaging (MRI) to Assess Changes to Trabecular Microarchitecture (Trb µArch) of the Hip

BACKGROUND . Calculated loss rates in trabecular (Trb) volumetric bone mineral density (vBMD), in astronauts after return from 6-month long-duration (LD) spaceflight, are rapid relative to menopause-induced loss rates and could contribute to the observed lack of recovery. Perforations in the Trb bony struts, skeletal fragility and fractures [5] have been associated with the rapid rate of bone loss in women due to menopause. The more rapid loss rate observed in astronauts could be inducing similar, irreversible losses of trabecular connectivity as seen in cadaver studies of female skeletons. These changes are not detectable by DXA technology and would not be discovered in astronauts during scheduled, triennial DXA testing for primary osteoporosis. High-resolution-peripheral quantitative computed tomography (HR-pQCT) of the lower leg have detected losses in Trb vBMD (vBMD) and changes in Trb microarchitecture (µArch) in astronauts immediately following routine 6-month spaceflights and continuing in some individuals for 1 or more years postflight with no signs of recovery. Resolution of these microarchitectural changes by whole body QCT, especially in the deeply embedded hip bone, is prohibitive due to excessive and unsafe radiation exposures. While HR-pQCT has sufficient resolution to study Trb µArch at safe and lower radiation exposure testing is restricted only to the lower leg and wrist. Hence, a technology to detect detrimental changes to Trb µArch in astronauts, especially of the hip, is needed to inform type and timing of countermeasures to irreversible deficits (preflight, inflight and postflight). METHODS . This HRP-funded study (2023-2027) will verify the sensitivity of a protocol for MRI scanning (on a 3T Siemens Vida) to detect changes to hip Trb µArch in persons following spinal cord injury (SCI); skeletal immobilization below the spinal lesion will serve as an analog for non-weight-bearing during spaceflight. The study period has been extended by 1 yr due to delayed Richmond IRB approval in Y1. A 3T MRI protocol will characterize serial changes in hip Trb µArch in SCI patients from time of admission at the Richmond VA Medical Center to their scheduled annual exam 12-months later. SCI patients with age, sex, and physical characteristics like ISS astronauts will be consented. The ability of 3T MRI hip scan to discriminate loss of trabecular connectivity subjects with SCI will be compared to age- and sex-matched ambulatory controls. A comparison between HR-pQCT and MRI measurements at the ankle (distal tibia) of study subjects will also be performed. A modified DXA scan analysis (3D-Shaper) will also be verified as a potential method for monitoring concurrent changes in hip Trb bone over 12-month. SIGNIFICANCE . Deliverables: a surveillance method for assessing for irreversible losses of connectivity and how skeletal changes after LD spaceflight(s) would modify the terrestrial risk of primary osteoporosis.

Risk Surveillance↗
NASA NTRS2023

Human Systems Integration: Managing Risk in Anesthesia

The practice of anesthesia relies on clinicians’ ability to safely manage increasingly complex equipment. Devices such as ventilators, drug infusion pumps, and physiologic monitors use sophisticated algorithms to deliver care, but most clinicians are only trained to manage automated systems during normal operation. Few if any receive training on how to manage system failures. Although manufacturers are required to consult with human factors engineers as part of the equipment design process, most pieces of equipment are ultimately brought to market without extensive input from clinicians. Systems in the operating room can be as simple as an oxygen tank, or as complex as a multi-institutional healthcare organization. Humans are also a complex system, and play a critical role in the domains of operations, design, fabrication, maintenance, repair, and ultimately, dismantling and closeout. HSI seeks to provide a means for advocating the human side of the system. Human Systems Integration (HSI) is the cross disciplinary process used as part of the Systems Engineering process to reduce risk in systems. HSI professionals consider the human, hardware, and software elements of system design to optimize system performance and improve safety. HSI professionals work in domains of study that include training, management, human factors engineering, safety, and occupational health, among others. This article discusses the role of systems in the practice of anesthesia, and how consideration of the human during all phases of the system life cycle helps manage risks and promote a better patient outcome.

Human Factors↗
NASA NTRS1966

Simulator effects partial gravity conditions

Adjustable apparatus which simulates partial to zero gravity partially supports the weight of convalescing patients in rehabilitation exercises. This device is an ideal tool for physical therapy.

Johnson, H. I.↗
NASA NTRS1968

New electrical plethysmograph monitors cardiac output

Four-electrode impedance plethysmograph measures ventricular stroke volume of cardiac output of humans. The instrument is automatic, operates with only one recording channel, and minimizes patient discomfort.

Kubicek, W. B.↗
NASA NTRS1969

Miniature oxygen resuscitator

Miniature, portable resuscitation system is used during evacuation of patients to medical facilities. A carrying case contains a modified resuscitator head, cylinder of oxygen, two-stage oxygen regulator, low pressure tube, and a mask for mouth and nose.

Johnson, G.↗