Space MedicineSpace Medicine
What is Space What is Space Medicine?Medicine?
The study of how The study of how different body systems different body systems work in a zero gravity work in a zero gravity environment.environment.
What kind of counter What kind of counter measures help maintain measures help maintain normal body function.normal body function.
Body System ChangesBody System Changes
Almost every system of the human body is Almost every system of the human body is affected when the human body enters zero affected when the human body enters zero gravity.gravity. GI Function (your bowels)GI Function (your bowels) Liver Function (how your body processes waste)Liver Function (how your body processes waste) Fluid and Electrolyte imbalancesFluid and Electrolyte imbalances Circulatory dynamics (the heart)Circulatory dynamics (the heart) Organ blood flow Organ blood flow Hormonal and metabolic (how you burn energy)Hormonal and metabolic (how you burn energy) Muscles and bones Muscles and bones
Effects on the Cardiovascular Effects on the Cardiovascular SystemSystem
There is a fluid shift in microgravityThere is a fluid shift in microgravity Facial Edema, cranial veins dilate, heart enlargementFacial Edema, cranial veins dilate, heart enlargement Blood no longer pulled to extremeties, which induces rapid loss Blood no longer pulled to extremeties, which induces rapid loss
of waterof water Upon return to Earth the body rapidly returns to normal fluid Upon return to Earth the body rapidly returns to normal fluid
shifts which can cause orthostatic hypotentsion and syncope.shifts which can cause orthostatic hypotentsion and syncope.
Counter Measure for Counter Measure for Cardiovascular ShiftsCardiovascular Shifts
LBNP (Lower Body Negative Pressure Device) device as substitute LBNP (Lower Body Negative Pressure Device) device as substitute for Earth’ gravity. Protocols may vary based on time spent in space.for Earth’ gravity. Protocols may vary based on time spent in space. Creates an equivalent physiologic stress by creating suction on the lower bodyCreates an equivalent physiologic stress by creating suction on the lower body
Ingestion of Isotonic Saline just before re-entry also helps to counter Ingestion of Isotonic Saline just before re-entry also helps to counter orthostatic intolerance and Cardiovascular Deconditioning.orthostatic intolerance and Cardiovascular Deconditioning.
Use of G-suits upon re-entry to help with orthostatic intolerance.Use of G-suits upon re-entry to help with orthostatic intolerance.
Operational Tilt TestOperational Tilt Test
. .
Operational Tilt TestingOperational Tilt Testing Operational Tilt Test is Pre-Operational Tilt Test is Pre-
flight and Post-flight test to flight and Post-flight test to determine the crewmembers determine the crewmembers orthostatic intolerance. orthostatic intolerance.
Upon return to Earth sometimes Upon return to Earth sometimes the crew will have a hard time the crew will have a hard time maintaining blood pressure maintaining blood pressure above their heart which leads to above their heart which leads to decreased blood flow to the decreased blood flow to the brain which can result in brain which can result in fainting.fainting.
During the test the crew’s ECG During the test the crew’s ECG and blood pressure, and and blood pressure, and ultrasound echo are constantly ultrasound echo are constantly monitoredmonitored
Effects on BoneEffects on Bone
Once Gravitational Stress is removed the Once Gravitational Stress is removed the bone calcium and phosphorus are bone calcium and phosphorus are excessively excreted.excessively excreted.
3.2 % of average bone loss occurs after 3.2 % of average bone loss occurs after nearly 10 days of weightlessness.nearly 10 days of weightlessness.
Can lead to bone fracturesCan lead to bone fracturesTherefore Countermeasures extremely Therefore Countermeasures extremely
necessarynecessary
Countermeasure to Reduce Countermeasure to Reduce Bone LossBone Loss
Weight bearing exercise Weight bearing exercise can reduce bone loss. can reduce bone loss. (Advanced Resistive (Advanced Resistive Exercise Device –ARED)Exercise Device –ARED)
Treadmill and Ergometer Treadmill and Ergometer and use of LBNP and use of LBNP combination (this combination (this combination helps to combination helps to prevent loss of prevent loss of coordination between the coordination between the nervous system and the nervous system and the muscles which affect muscles which affect balance and motion.) balance and motion.) Regimen is for 2 hours of Regimen is for 2 hours of exercise per day.exercise per day.
Nutritional Supplements Nutritional Supplements also being evaluated.also being evaluated.
Mike Foal
Sunita Williams Completes the Boston Marathon in Space
Effects on MuscleEffects on Muscle Rapid Atrophy due to lack of use in the Rapid Atrophy due to lack of use in the
microgravity environment.microgravity environment. Muscle fibers have two categories: Slow-twitch Muscle fibers have two categories: Slow-twitch
muscle fibers, and fast-twitch muscle fibers. muscle fibers, and fast-twitch muscle fibers. In microgravity there is rapid degradation of In microgravity there is rapid degradation of
muscle fibers from slow twitch to fast twitchmuscle fibers from slow twitch to fast twitch Slow twitch are more efficient at using oxygen to Slow twitch are more efficient at using oxygen to
generate more ATP for continuous muscle generate more ATP for continuous muscle contractions and don’t fatigue as fast. contractions and don’t fatigue as fast.
Fast twitch use anaerobic metabolism which Fast twitch use anaerobic metabolism which makes them better at short bursts of strength or makes them better at short bursts of strength or speed and fatigue fast. speed and fatigue fast.
Countermeasure for Muscle Countermeasure for Muscle DegradationDegradation
Includes an exercise protocol Includes an exercise protocol that induces maximum muscle that induces maximum muscle power for a long distance. (ie power for a long distance. (ie Treadmill running, bike training Treadmill running, bike training (ergometer)(ergometer)
New research into Pulsed New research into Pulsed Electromagnetic Fields on the Electromagnetic Fields on the tissue at a cellular level to tissue at a cellular level to induce use of both muscle induce use of both muscle fibers. May also prove useful fibers. May also prove useful in keeping bone loss at bay. in keeping bone loss at bay. http://research.jsc.nasa.gov/Phttp://research.jsc.nasa.gov/PDF/SLiSci-12.pdfDF/SLiSci-12.pdf
Space Motion SicknessSpace Motion Sickness Space Motion Sickness usually occurs a few Space Motion Sickness usually occurs a few
minutes or a few hours after entering minutes or a few hours after entering weightlessness.weightlessness.
Characterized by headaches, malaise, nausea Characterized by headaches, malaise, nausea and vomitingand vomiting
60-70% of all astronauts experience this.60-70% of all astronauts experience this. Usually occurs first few days and then Usually occurs first few days and then
disappears disappears This occurs due to vestibular, inner ear, visual, This occurs due to vestibular, inner ear, visual,
skin and joint/muscle receptors by the exposure skin and joint/muscle receptors by the exposure to microgravity.to microgravity.
Countermeasure for Space Motion Countermeasure for Space Motion SicknessSickness
Biofeedback training Biofeedback training Adaptation training using virtual realityAdaptation training using virtual realityWater immersion trainingWater immersion training
Medications are used upon symptoms of Medications are used upon symptoms of the Space Motion Sickness (ie. the Space Motion Sickness (ie. Promethazine hydrochloride)Promethazine hydrochloride)
Hematologic and Immunologic Hematologic and Immunologic SystemSystem
In Microgravity there is a change in the shape of In Microgravity there is a change in the shape of the red blood cells (Spherical vs Discoid Shape) the red blood cells (Spherical vs Discoid Shape) ADD PICTUREADD PICTURE
Anemia is characterized after 4 days into space Anemia is characterized after 4 days into space flight. (decrease in the number of red blood flight. (decrease in the number of red blood cells)cells)
After 3 months in space there is a 15% decrease After 3 months in space there is a 15% decrease in red blood cell volume.in red blood cell volume.
They will return to normal upon return to Earth’s They will return to normal upon return to Earth’s Gravitational ForcesGravitational Forces
Activity of lymphocytes reduces but has rarely Activity of lymphocytes reduces but has rarely caused practical problemscaused practical problems
Effects of Space RadiationEffects of Space Radiation
Astronauts are subject to more Radiation Astronauts are subject to more Radiation than they would be exposed to on Earth.than they would be exposed to on Earth.Galactic cosmic radiation Galactic cosmic radiation Solar Particle radiation (from the sun)Solar Particle radiation (from the sun)Geomagnetically trapped radiationGeomagnetically trapped radiation
Crew must monitor their radiation level Crew must monitor their radiation level with personal dosimeterswith personal dosimeters
Could have potential effects of infertility, Could have potential effects of infertility, cancer and other diseasescancer and other diseases
Interesting Facts Interesting Facts During the Apollo program, there were several near-During the Apollo program, there were several near-
misses between the astronauts walking on the surface of misses between the astronauts walking on the surface of the Moon and a deadly solar storm event. The Apollo 12 the Moon and a deadly solar storm event. The Apollo 12 astronauts walked on the Moon only a few short weeks astronauts walked on the Moon only a few short weeks after a major solar proton flare would have bathed the after a major solar proton flare would have bathed the astronauts in a 100 rem blast of radiation. Another major astronauts in a 100 rem blast of radiation. Another major flare that occurred half way between the Apollo 16 and flare that occurred half way between the Apollo 16 and Apollo 17 moonwalks would have had a much more Apollo 17 moonwalks would have had a much more deadly outcome had it arrived while astronauts were deadly outcome had it arrived while astronauts were outside their spacecraft playing golf. Within a few outside their spacecraft playing golf. Within a few minutes, the astronauts would have been killed on the minutes, the astronauts would have been killed on the spot with an incredible 7000 rem blast of radiation. The spot with an incredible 7000 rem blast of radiation. The daily dosage of radiation on the Space Station is about daily dosage of radiation on the Space Station is about equal to 8 chest X-rays per day. equal to 8 chest X-rays per day.
Are We Ready for Mars?Are We Ready for Mars?
There are still many things that we need to There are still many things that we need to understand about the human body’s understand about the human body’s response to a microgravity environment.response to a microgravity environment.
NASA in collaboration with the NIH and NASA in collaboration with the NIH and other Research universities are constantly other Research universities are constantly conducting studies to determine more conducting studies to determine more effective countermeasures to combat effective countermeasures to combat these effects.these effects.
Using The Zero G Airplane for Using The Zero G Airplane for Testing CountermeasuresTesting Countermeasures
Zero G Zero G Airplane Airplane
EnvironmentEnvironment
Why test Why test experiments in experiments in Zero G plane?Zero G plane?
18-24 sec 18-24 sec Weightlessness Weightlessness per parabolaper parabola
30-40 parabolas 30-40 parabolas per flightper flight
Properties of Water in Zero GProperties of Water in Zero Go individual H2O molecule is electrically
polarized,
o meaning the end with the two hydrogen atoms has a small positive electric charge, while the end with the oxygen atom has a small negative charge.
o A loose electrical connection called "hydrogen bonds" form between neighboring molecules: The positive end of one molecule hooks up with the negative end of its neighbor, and with enough of these hydrogen bonds in place throughout the bubble, the water clings to itself, surface tension
o On Earth, gravity overrides the effects of hydrogen bonds, making a bubble of water splat on the ground.
The ENDThe END
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