Members Can Post Anonymously On This Site
ERS-2 buckles and bends during final farewell
-
Similar Topics
-
By NASA
5 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
In-person participants (L-R) – Back row: Jason Lytle, Stuart Lee, Eric Bershad, Ashot Sargsyan, Aaron Everson, Philip Wells, Sergi Vaquer Araujo, Steven Grover, John A. Heit, Mehdi Shishehbor, Laura Bostick; Middle row: Sarah Childress Taoufik, Stephan Moll, Brandon Macias, Kristin Coffey, Ann-Kathrin Vlacil, Dave Francisco; Front row: James Pavela, Doug Ebert, Kathleen McMonigal, Esther Kim, Emma Hwang; Not pictured: Tyson Brunstetter, J. D. Polk
Online participants: Stephen Alamo, Mark Crowther, Steven Nissen, Mark Rosenberg, Jeffrey Weitz, R. Eugene Zierler, Serena Aunon, Tina Bayuse, Laura Beachy, Becky Brocato, Daniel Buckland, Jackie Charvat, Diana Cruz Topete, Quinn Dufurrena, Robert Haddon, Joanne Kaouk, Kim Lowe, Steve Laurie, Karina Marshall-Goebel, Sara Mason, Shannan Moynihan, James Pattarini, Devan Petersen, Ruth Reitzel, Donna Roberts, Lucia Roccaro, Mike Stenger, Terry Taddeo, Gavin Travers, Mary Van Baalen, Liz WarrenNASA In October 2024, NASA’s Office of the Chief Health and Medical Officer (OCHMO) initiated a working group to review the status and progress of research and clinical activities intended to mitigate the risk of venous thromboembolism (VTE) during spaceflight. The working group took place over two days at NASA’s Johnson Space Center; a second meeting on the topic was held in December 2024 at the European Space Agency (ESA) facility in Cologne, Germany.
Read More about the Risk of VTE The working group was assembled from internal NASA subject matter experts (SMEs), the NASA OCHMO Standards Team, NASA and ESA stakeholders, and external SMEs, including physicians and medical professionals from leading universities and medical centers in the United States and Canada.
Background
Spaceflight Venous Thrombosis (SVT)
Spaceflight Venous Thrombosis (SVT) refers to a phenomenon experienced during spaceflight in which a thrombus (blood clot) forms in the internal jugular vein (and/or associated vasculature) that may be symptomatic (thrombus accompanied by, but not limited to, visible internal jugular vein swelling, facial edema beyond “nominal” spaceflight adaptation, eyelid edema, and/or headache) or asymptomatic. Obstructive thrombi have been identified in a very small number of crewmembers, as shown in the figure below.
Note that the figure below is for illustrative purposes only; locations are approximate, and size is not to scale.
Approximate location of identified thrombi in crewmembers.Source: Modified from Cerebral Sinus Venous Thrombosis – University of Colorado Denver With treatment, crewmembers were able to complete their mission, and anticoagulants were discontinued several days prior to landing to minimize the risk of bleeding in the event of a traumatic injury. Some thromboses completely resolved post landing, and some required additional treatment.
Pathophysiology of Venous Thromboembolism (VTE)
The proposed pathogenesis of VTE is referred to as Virchow’s triad and suggests that VTE occurs as the result of:
Alterations in blood flow (i.e., stasis), Vascular endothelial injury/changes, and/or, Alterations in the constituents of the blood leading to hypercoagulability (i.e., hereditary predisposition or acquired hypercoagulability). Note: pathophysiology are the changes that occur during a disease process; hypercoagulability is the increased tendency to develop blood to clots.
The Virchow’s triad of risk factors for venous thrombosis.Bouchnita, 2017 Blood stasis, or venous stasis, refers to a condition in which the blood flow in the veins slows down which leads to pooling in the veins. This slowing of the blood may be due to vein valves becoming damaged or weak, immobility, and/or the absence of muscular contractions. Associated symptoms include swelling, skin changes, varicose veins, and slow-healing sores or ulcers. In terrestrial medicine, venous thrombosis is typically caused by damaged or weakened vein valves, which can be due to many factors, including aging, blood clots, varicose veins, obesity, pregnancy, sedentary lifestyle, estrogen use, and hereditary predisposition.
Spaceflight Considerations
Altered Venous Blood Flow and Spaceflight Associated Neuro-ocular Syndrome
In addition to the terrestrial risk factors of VTE, there are physiological changes associated with spaceflight that are hypothesized to potentially play a role in the development of VTE in weightlessness. Specifically, researchers have explored the effects of the microgravity environment and subsequent observed headward fluid shifts that occur, and the potential impact on blood flow. Crewmembers onboard the International Space Station (ISS) experience weightlessness due to the microgravity environment and thus experience a sustained redistribution of bodily fluids from the legs toward the head. The prolonged headward fluid shifts during weightlessness results in facial puffiness, decreased leg volume, increased cardiac stroke volume, and decreased plasma volume.
Crewmembers have also experienced altered blood flow during spaceflight, including retrograde venous blood flow (RVBF) (the backflow of venous blood towards the brain) or stasis (a stoppage or slowdown in the flow of blood). While the causes of the observed stasis and retrograde blood flow in spaceflight participants is not well understood, the potential clinical significance of the role it may have in the development of thrombus formation warrants further investigation.
Doppler imaging of a retrograde flow in the left internal jugular vein.Yan & Seow, 2009 Other physiological concerns affected by fluid shifts are being studied to consider if any relation to VTE exists. Chronic weightlessness can cause bodily fluids such as blood and cerebrospinal fluid to move toward the head, which can lead to optic nerve swelling, folds in the retina, flattening of the back of the eye, and swelling in the brain. This collection of eye and brain changes is called “spaceflight associated neuro-ocular syndrome,” or SANS. Some astronauts only experience mild changes in space, while others have clinically significant outcomes. The long-term health outcome from these changes is unknown but actively being investigated. The risk of developing SANS is higher during longer-duration missions and remains a top research priority for scientists ahead of a Mars mission.
Conclusions and Further Work
Based on expert opinion and the assessment of the risk factors for thrombosis, an algorithm was developed to provide guidance for in-mission assessment and treatment of thrombus formation in weightlessness. The algorithm is based on early in-flight ultrasound testing to determine the flow characteristic of the left internal jugular vein and associated vasculature.
NASA Working Group Recommendations
The working group recommended several areas for further investigation to assess feasibility and potential to mitigate the risk of thrombosis in spaceflight:
Improved detection capabilities to identify when a thrombus has formed in-flight, Pathophysiology/factors leading to thrombi formation during spaceflight, Countermeasures and treatment
For more information on the working group meeting and a complete list of references, please see the Risk of Venous Thromboembolism (VTE) During Spaceflight Summary Report.
Risk of Venous Thromboembolism (VTE) During Spaceflight Summary Report Share
Details
Last Updated Mar 14, 2025 EditorKim Lowe Related Terms
Office of the Chief Health and Medical Officer (OCHMO) Astronauts General Human Health and Performance Humans in Space The Human Body in Space Keep Exploring Discover Related Topics
OCHMO Independent Assessments
Independent assessment plays a crucial role in NASA’s long-term success by addressing essential questions requiring rapid response to support further…
Aerospace Medical Certification Standard
This NASA Technical Standard provides medical requirements and clinical procedures designed to ensure crew health and safety and occupational longevity…
Human Spaceflight Standards
The Human Spaceflight & Aviation Standards Team continually works with programs to provide the best standards and implementation documentation to…
Human Spaceflight and Aviation Standards
The Human Spaceflight and Aviation Standards Team continuously works with subject matter experts and with each space flight program to…
View the full article
-
-
By NASA
3 Min Read NASA, Partners to Conduct Space Station Research During Expedition 73
NASA NASA astronauts are gearing up for a scientific mission aboard the International Space Station. Expedition 73 NASA astronauts Nichole Ayers and Anne McClain, JAXA (Japan Aerospace Exploration Agency) astronaut Takuya Onishi, and Roscosmos cosmonaut Kirill Peskov will launch in March as part of the agency’s SpaceX Crew-10 mission. NASA astronaut Jonny Kim will join the crew when he launches aboard the Roscosmos Soyuz MS-27 spacecraft in April alongside Roscosmos cosmonauts Sergey Ryzhikov and Alexey Zubritsky.
Read more about some of the microgravity research planned by NASA and its partners:
Subjects for human research
NASA Astronauts often serve as test subjects, submitting blood and other samples for research. NASA astronaut Anne McClain is pictured submitting a sample on a previous mission with assistance from CSA (Canadian Space Agency) astronaut David Saint-Jacques. McClain will participate in NASA’s Complement of Integrated Protocols for Human Exploration Research investigation, or CIPHER, a suite of integrated studies on physiological and psychological changes seen in space. Results could provide valuable insights for future deep space missions.
Testing lunar navigation
NASA When Expedition 73 astronauts engage with students worldwide via the ISS Ham Radio program, researchers will use the ham radio hardware to test software for the Navigation and Communication Testbed (NAVCOM) that could help shape future lunar navigation. Researchers from the investigation recently launched a related study to the Moon aboard Firefly’s Blue Ghost to help bridge existing Earth navigation with emerging lunar-specific solutions.
Advancing fire safety
NASA Expedition 73 is scheduled to conduct a Material Ignition and Suppression Test (SoFIE-MIST), testing material flammability in microgravity. This research could improve fire safety on future missions, contributing to models used to select materials for space facilities and helping to determine the best ways to extinguish fires in space.
Keeping blood flowing
Angelo Taibi/ASI Expedition 73 crew members will participate in Drain Brain 2.0, which examines how blood flows from the brain to the heart in microgravity using this plethysmograph, a device that can record the volume of blood drainage from the skull. Results could identify which processes in the body compensate for the lack of gravity, helping to ensure proper blood flow for astronauts on future missions and people with cardiovascular issues on Earth.
The International Space Station is a convergence of science, technology, and human innovation that enables research not possible on Earth. For more than 24 years, NASA has supported a continuous U.S. human presence aboard the orbiting laboratory, through which astronauts have learned to live and work in space for extended periods of time. The space station is a springboard for developing a low Earth economy and NASA’s next great leaps in exploration, including missions to the Moon under Artemis and, ultimately, human exploration of Mars.
Learn more about the International Space Station, its research, and its crew, at:
https://www.nasa.gov/station
Keep Exploring Discover More Topics From NASA
Space Station Research and Technology
Humans In Space
Space Station Research Results
Human Research Program
Share
Details
Last Updated Mar 10, 2025 Related Terms
ISS Research International Space Station (ISS) View the full article
-
By Space Force
U.S. military general officers and senior enlisted advisors headlined a senior leader panel during the 32nd annual National Character and Leadership Symposium at the U.S. Air Force Academy, Colorado, Feb. 21.
View the full article
-
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.