"There are people whose work - lying in a bathtub": how to study the effect of weightlessness on the astronauts health
Forming / / December 19, 2019
There are people whose work - lying in a bathtub. Lie down for hours, even days on end (and get paid for it). However, do not envy them - we are talking about the participants of complex scientific experiments, in which doctors from Institute of Biomedical Problems, Russian Academy of Sciences study human exposure conditions similar to conditions weightlessness. By itself, this experience, as any long stay in space, resulting in a malfunction of the body.
About how and why was invented by way of a "dry" immersion and what research results it allows you to get, we asked to speak to staff IBMP RAS Love Ilya Amirov and Rukavishnikov. In addition, we suggest to familiarize with the diary participants "dive", which lasted five days, an engineer and a popularizer of cosmonautics Alexander Khokhlov. The recordings were made directly during the experiment time.
Staying in space, even on well-protected space ship, adversely affects the health of astronauts. In space flight almost everything for the body strange and hostile - increased radiation background, microgravity, insulation, artificial atmosphere and lighting, and the monotony of sensory stimuli to drive in homesickness. Among these factors is specific to only the microgravity of space flight and hardly reproducible in terrestrial conditions.
At the dawn of the era of space exploration was considered the main danger is not microgravity, and overload, and it is to him actively preparing astronauts. With the advancement of technology the flights became more and more persistent, and in June 1970, Soviet cosmonauts Andrian Nikolayev and Vitaly Sevastyanov make a first long 18-day spaceflight, set record for the duration of continuous filter, and returned to Earth... can not stand and walk. The state of the astronauts was depressing: muscular atrophy, negative reactions on the part of the cardiovascular system.
This state of affairs led me to two conclusions of scientists. Firstly, the need to develop prevention system (to such happens again!) And, secondly, to study the effect of weightlessness on the human body (in order to understand the fundamental laws of influence weightlessness). It became clear that, without a large amount of data about the changes in each organ system to send astronauts into space is impossible. But how to study the effect of weightlessness on the human body without space?
Immersion in weightlessness
Do scientists have found a Solomonic solution to this problem - simulation of conditions of weightlessness on Earth. Such simulating spaceflight experiments called model (or models), and their effect on the body similar to the effects of weightlessness. Since the main factors affecting the condition of the astronauts, become physically unloading, fluid shifts and lack of support, and they formed the basis of model experiments.
In modern science, no one model experiment can not fully reproduce the conditions of weightlessness, so Depending on what the scientists plan to study carefully chosen object of study and experimental model. Quite often in the role of "subjects" are the laboratory animals such as mice and rats, but the most valuable information to give the model experiments on people - volunteers tested.
Publish fragments of records that in his Facebook conducted design engineer of Space Instrument RTC, popularizer of cosmonautics Alexander Khokhlov, who took part in the experiment "Effectiveness of low frequency EMC in preventing muscle deconditioning, developing in a terrestrial environment modeling space flight ", which in March-April this year was held at the Institute of Biomedical Problems of the Russian Academy of Sciences (SSC RF - IBMP RAS).
26 March
Force majeure, or fate can not escape
"This morning, found that test, which was in front of me, got sick, I was urgently summoned to the IBMP, and I enter a day earlier in the experiment. The immersion bath I go on Thursday (the first in the second tab). Today were experimenting, "Pose", "Field Test", "vision", "Breath", "H-Reflex", "Algometriya" and "Vulcan-I." On the "view" I put weights on the eyes (four minutes), after having dripped analgesic. So earlier we measured the intraocular pressure to astronauts, and then went on the air. "
March 29
Go!
"My participation in the experiment turned into a new phase. Around 9:30, I was plunged into a bath of dry immersion for five days.
Water, with a comfortable temperature, closed film, which fits my body from all sides. It peeking out only the head and sometimes hands. from the film protects the body sheet, which changes every day. Of clothing: socks, shorts and T-shirt.
The first day goes unusual. New sensations that worsen at night. Our lives in dry immersion baths round the clock support on duty brigade of three people: a doctor, technician and technician.
Bored here is not necessary, replaced by an experiment by experiment, everyday moments, too, takes time. In the evening, started the first three-hour electromyostimulation. Her presence - the main difference between this experiment in a bath of dry immersion previous. Low-frequency EMC can help to overcome the harmful effects of weightlessness on the astronauts, as well as older people with limited mobility in the world. Stimulation resembles point rhythmic pat on the thighs and shins. "
To study the effect of weightlessness on the human body, there are several ways. For example, this can be done in the incident on a parabolic trajectory plane. That's just the duration of weightlessness phase in this case is so small that we can not speak about the long-term effects.
To achieve stronger effects you can just lie on the bed, in which the head end will be omitted. Bed rest will lead to muscle atrophy and permanent blood rushes to your head will bring the state of the cardiovascular system of the subject to that of the astronaut. However, lie will have a long time - at least several weeks, preferably several months.
The most unusual and, at the same time the most approximate to the effects of zero-gravity model - a "dry" immersion (from the English. immersion - "immersion"), in which the man for a few days or weeks immersed in water.
Invention, the following observation model helped - long stay in the water affects the human body similar to weightlessness manner. The first immersion immersion were "wet" - the subjects were in the pool with fresh water for several days.
On the one hand, scientists speculate about the similarity of the observed changes were confirmed, but on the other hand, due to the constant contact with water in people literally started peeling off the skin. Testers volunteers did not help protective ointment, and the pool side became black from nasevshego them and oxidized sebum. Also, the subjects that they are not drowned, it was forbidden to sleep in the pool, and the on duty doctors were forced to close their wake.
acute adaptation
"The first night in an immersion bath was difficult. Dozed off around 00:00, I soon woke up with a strange sensation that grips me the water through the film, began to ache back, then pulled stomach (started to swell). And I eventually slept for only two hours in the morning, and six have already looked at the ceiling.
In the morning until 10:00 in my experiments were performed on an empty stomach. For example, SPLANH in which the ultrasound showed that I had in the stomach and intestine a lot of air. Enough days in the bath. I have no appetite. For dinner, I plan to just drink.
Since the period of adjustment still only talking, it is difficult to read and write, so basically listening to music on headphones. Boredom is not necessary, the attention of the rescue teams and researchers lacking.
And yet the good. One experiment is called "Kefir", and in the evening we drink a cup of tasty and healthy product. "
It became clear that the experiment in such conditions it is impossible to model and needs substantial improvement. The most elegant version of its improvement was offered at the Institute of Biomedical Problems E. B. Shulzhenko and I. F. Wil Williams in the early 70s. Pool covered waterproof fabric large area that the subject was completely immersed in the water column, but it does not touch the sides and bottom of the bowl. On the surface, leaving only the head and hands of the subject.
The "Professor Dowell's Head" mode, under the close supervision of a physician and researchers volunteer lives throughout the experiment. The exception is during evening hygiene - Dirt is not held in high esteem among scientists. Before going to sleep test is taken out of the immersion bath, immersed in the pomyvochnaya gurney and taken to the shower. "Relax" is allowed no more than 15 minutes on a heavy day's work. Since the model of "dry" immersion applied practically unchanged.
In space, well, the world is better
Man, far from space biology, it may seem that a more than 55-year history of manned space exploration human in space studied far and wide. But this is only partly true.
Yes, the basic laws that happen to an astronaut in flight, are known - in weightlessness in a different way working heart and blood vessels, reduces the amount of fluid in the body, there are muscle weakness and motor illusion. But no scientist will tell you that all open changes are described in detail and do not require further study.
Despite the fact that in the space have visited hundreds of people, most extensive biological surveys rarely include more than 15-20 astronauts. Even such small, in terms of statistical analysis, the group takes several years of preparatory work, often creating a new equipment (suitable for the stringent requirements of the International Space Station) and training of astronauts all the subtleties of biological surveys.
Away from the bustle of the earth studies are sedate and measured - usually for a year in a single experiment can participate three to five astronauts, and from the inception of the hypothesis to its fruit, so that it can take half-dozen years.
Many studies are often carried out in parallel, both in space and in the "dry" immersion that allows us to compare the observed changes. For example, it is shown that the seven days of space flight, and seven days of immersion cause similar changes in the cardiovascular system associated with changes in fluid balance in the body.
Gen. in immersion, or "Formula 1"
"That night I slept for seven hours was better, the body adapts to the unusual conditions. It turned out, the testers are divided into those who suffer more back, and those who have stomach. My stomach. But there are those who receive a set of surprises. Therefore, one of the favorite jokes of researchers - is to offer a tester who came out of the bathroom, again lie down to relax.
If the experiment he conducted two dozen scientists, the way of life associated with the brigade on duty. Brigade on duty feeding test three times a day, watching cyclogram day takes to analyze blood and saliva, bringing the duck for small needs, helping scientists to conduct tests.
The most interesting thing going on in the evening. All day testers, like jellyfish, swaying in the bathrooms, but sometimes they are taken out. For some tests you need to have access to the body. Every minute is fixed bath.
And in the evening for 15 minutes are carried out hygiene procedures under gravity. The brigade includes lift. Test rolls on the couch, and it is brought to the scales and gauge growth. He stands with the help of a doctor and measures performance. Then the test is placed in a conventional toilet with the toilet to go in big, after he lays down on the couch and pomyvochnaya taking a shower lying down. At this point, team cleans the tape and change the sheets in the bathtub. Next to the shower room on the team test, nestled towel it imported couch with clean shorts and socks. He alone rolls and dresses lying. His dovozyat to the bathroom, unloaded, put on a T-shirt with sensors experiment "Dream" and immersed in a bath. All of a maximum of 15 minutes. This "Formula 1".
Almost identical changes in space flight and immersion occur with muscles: reduced their tone and decreases the power. In both cases, this leads to lack of support. As it turned out, the support necessary musculoskeletal for normal functioning - bone in no shock loads that occur on Earth when walking and running, lose calcium and become brittle. In weightlessness fragile bones are not dangerous, but when you return to Earth, and in case of overload it may cause injury.
In the absence of supporting incentive affects not only the bones but also the muscles. Once the astronaut goes into a state of weightlessness, his muscles begin to lose their tone, that within a few weeks and leads to functional changes. Under the influence of the "dry" immersion, the same thing happens - from one day to lose muscle tone and strength, and when removed from the immersion test feel like a fish out of water.
Unidirectional changes enable scientists to conduct more detailed studies on Earth, freeing up time for other tasks astronauts.
Another important factor of space flight - a decrease in physical activity. Despite the fact that every day the astronauts perform a large amount of work quite actively move at stations and engage in physical exercise, the load on the body remains substantially less terrestrial. Everything with which they interact, has no weight, even themselves. Therefore, to achieve the goals of the motor requires very little muscular effort.
In the context of immersion is prohibited tester generate unnecessary muscular effort, and this was strictly monitored researchers. In return, the subject receives a command from 3-4 persons performing like a jinn, their needs and desires.
Fourth flight hours
"I Feel the impact on your body, similar to weightlessness in space flight. As there, my back aches (fortunately, not much), a bit stuffy nose and there are problems with the gases in the stomach and intestines.
Every day I pass three hour electromyostimulation feet, that I ought to facilitate the return to Earth in two nights. On Tuesday morning, I went back to the usual vertical position. I felt much better than in the second day of immersion, the body gets used. But the appetite is not returned, it willed.
For breakfast we yogurts, different cereals to choose from, dried fruits. Lunch: soup (broth with egg, mushrooms, meatballs and so on), main dish, beverage, dry bread, salad. For dinner, main dish and salad.
We eat at a position with a pillow under his back, to swallow normally. But still not very convenient. Only on the first day, before the start of acute adaptation, I eat everything now - less than half of the put diet.
Drinks: tea, water, juice and jelly. Coffee should not be on the conditions of the experiment. "
It is important to understand that, despite the advances in technology, not all studies can be performed in space. In the model of "dry" immersion such restrictions significantly less. For example, magnetic resonance imaging (MRI scanner in orbit - sounds fantastic!) And transcranial magnetic stimulation weightlessness is not carried out even once, but thanks to the data obtained in the immersion, the scientists has an idea of what to expect in space.
There are those studies that statement is not only technically difficult but also entails risks for the astronaut. For example, recall biopsy - removal of a small piece of tissue. This study requires sterile conditions experienced surgeon operating and hands, but even with all conditions there is little chance of complications. For astronauts in orbit this unnecessary risk. Nevertheless, such studies are carried out in immersion and invite you to explore the secrets of extremely difficult arranged skeletal muscle.
Higher
To tell exactly what results can be achieved thanks to the "dry" model of immersion, dwell on a series of experiments devoted to the study of back pain and increase the growth of astronauts during the transition to weightlessness.
Back pain occur in astronauts in the early days of flight, as well as in test in a "dry" immersion. Previous studies failed to show that under conditions of weightlessness due to changes transport nutrients intervertebral disks increases, and within their structures accumulated liquid. In addition, the pain could be due to the impact on the sensitive roots of the spinal cord as a result of increase in length of the spine.
The cause of these disorders, as shown by studies carried out in the SSC RF - IBMP RAS over a number of years may be a reduction in muscle tone, back extensors. The assumption of the presence of the muscles involved in maintaining posture, was put forward by V. FROM. Gurfinkel more in 1965.
Change of tone in the muscles - leg extensor regularly recorded in the previous modeling studies. So there were grounds for assuming that under weightless conditions also decreases muscle tone back that involved in maintaining posture in the world (they are called "within"), where the gravitational load causes them to remain in good shape.
To test this hypothesis, a series of simulation experiments with the "dry" immersion of different duration - from six hours to five days. At the same time studied muscle tone back with measurement of their transverse rigidity; parallel resonance means Vibrographs, miotonometry MRI investigated changes of the spine. In addition, the scientists measured the height and nature of emerging evaluated pain.
Home soon
"I started the last, the fifth day dry immersion in IBMP RAS. He feels well. I almost adapted to the conventional zero gravity. Tomorrow morning recess and a lot of tests. Today they are also missing.
During immersion, the testers are engaged in various experiments. This study of the pain threshold ( "Algometriya"), and changes in vision in immersion, and the ability to control the load compressing the palm ( "dynamometer") and touch the feet ( "pedal").
Many devices that are now available or are on board the ISS, or are used before and after the flight to experiment with the astronauts.
In my spare time I listen to music and read a book "Beyond Earth".
The results showed that the pain is not related to radicular pain, and is muscular in nature, with no irradiation. Staying under gravity discharge is accompanied by decreased tone (or transverse stiffness) erectors, belonging to the group of postural muscles, doing it in the first hours and days, this process goes especially expression.
These changes resulted in increased astronaut growth in microgravity. In the lumbar spine, according to MRI, to increase the height of the intervertebral discs and smoothed lumbar lordosis.
The research group, which used a means of prevention, such as costume axial load "Penguin" and hardware complex myostimulation and evaluation of the severity of pain, as well as increased rates were lower compared with the group of "pure" immersion without the use of means prevention.
Not only for space
Model "dry" immersion fairly well reproduces the cosmic disturbances, but other than that, more and helps fight certain diseases. For example, immersion baths course brings relief to people with excessively increased muscle tone and prevents them from fully moving.
Take an immersion bath - a good way to lower blood pressure. The mechanism of the process is simple: ambient person squeezes water from the blood and lymph vessels in the central peripheral blood flow, It is perceived by the body as an overabundance of fluid and leads to its removal (naturally - increased urination) and lower pressure. By the way, in order to achieve this effect, the immersion is not necessary to be "dry" - perhaps, many have noticed that during the voyage begins to want the toilet, and now you know why.
To freedom with a clear conscience
"In the morning at 9:30 for me ended the fifth day dry immersion. I learned from the bathroom. Zero-day - one of the most important, for the sake of data in this day and testers are five days without support. On the gurney I was taken to the laboratory gravitational physiology, where the tests were conducted at once experiments "Architecture", "Pose", "Field Test" and then DEXA, "dynamometer" TMS "Tonus" "Izokinez".
My condition is improving with each passing minute, first head ached as if I had passed the 450 milliliters of blood, a little shaking legs with eyes closed tests. Now everything is good and the stomach does not hurt.
Today, I'm spending the night at the Institute for the experiment "Dream". Then two more days of research, and on April 11 - the last day on which the adventure with immersion for me to finish. It is a very rewarding experience that will be useful in the future.
It is interesting that the fall in the IBMP planned next phase of immersion - 21 days. But there is a special set. "
Model experiments are carried out in special medical or scientific establishments equipped with unique equipment under supervision of highly skilled researchers. Currently, the SSC RF - IBMP RAS is experimenting with the use of a five-day "dry" immersion.
Interestingly, the changes that occur in the body in immersion can simulate not only spaceflight, but also the state of senile sarcopenia - age-related atrophy of the skeletal musculature. This immersion is used for the first time low-frequency electromyostimulation leg muscles aimed at preventing adverse changes in muscle. Studies on the young, but detrenirovannyh test volunteers will be selected the most effective protocols of electrical stimulation.
After completion of the immersion test must pass a variety of tests that evaluate how the changed muscle tone, their structure, as well as the vertical stand and volunteers gait.
Publications, dedicated to medical and biological experiments in space and their modeling, are rare. This article was considered only a small part of this vast topics, including health of astronauts aboard the station, satellite launches, inhabited animals, model experiments involving primates and space technology in the rehabilitation of patients.
Literature
AND. B. Kozlovsky, D. BUT. Maksimov, Yu AND. Voronkov, MI Sund, V. N. Ardashev, IA G. Dorogan-Sushchev, IA IN. Rukavishnikov. Changes in the lumbar spine and acute back pain when exposed to 3-day "dry" immersion // Kremlin medicine. Clinical Gazette. — 2015. — № 2.
AND. IN. Rukavishnikov, LA E. Amirov, T. B. Kukoba, E. FROM. Tomilovskaya, IA B. Kozlovsky. Influence of gravitational unload the tone of the muscles of the back // Human Physiology. — 2017. — № 3.