Page 182 - International Space Station Benefits for Humanity, 3rd edition.

Cardiovascular and Vision Laboratory to evaluate peculiar factors of spaceflight. Indeed, normal,
these garments, including Evaluation of Compression good-quality sleep is the basis for maintaining the
Garments as Countermeasures to Orthostatic necessary, high psychological functioning and good
Intolerance and Evaluation of Commercial Compression physical condition of cosmonauts. However, the
Garments as a Countermeasure to Post-Spaceflight clinical method used to study sleep (polysomnography)
Orthostatic Intolerance. Following that initial work, requires the use of a large number of sensors, which
additional studies evaluated different amounts of lower- disturbs normal sleep, requires time and is too complex
body coverage and compression using test subjects for spaceflight.
in the laboratory, after bed rest (i.e., a way to simulate Thus, data on the sleep quality of cosmonauts in long-
spaceflight effects), and in astronauts after Space term weightlessness have been extremely limited.
Shuttle missions.
In 2007, a new device, Sonocard, arrived on the
NASA then partnered with a commercial manufacturer Russian Segment of the ISS, making it possible to
to produce a custom-fitted garment that is able to study sleep with a miniature device the size of a deck
provide continuous coverage across the lower body, of cards. The device is placed on the left in the top
with highest compression applied at the feet and pocket of the cosmonaut’s T-shirt before sleep, and
decreasing up to just above the waist. Designers its sensor elicits micro-fluctuations of the chest wall
modified a commercially available garment with a similar that are related to heart function. Upon wake-up, the
compression profile that worked well in the laboratory, information recorded during the night is sent to Earth
thus creating garments that are relatively easy to put for retrospective detail analysis in laboratory.
on in weightlessness and comfortable to wear during
re-entry and after landing. The symptoms of orthostatic Sonocard provides a contactless recording of
intolerance are expected to be most prevalent physiological signals, and its use does not require
immediately after landing. attaching electrodes or special sensors to the body.
Instead, it acquires its data by recording all the
Although these garments are designed specifically vibrations that are elicited by the sensor-accelerometer.
for use by astronauts, the Cardiovascular and Vision Pulse rate, breathing rate, movement activity and
Laboratory currently works with university-based heart rhythm variability are obtained. This method is
cardiologists on tests of a similar garment for clinical successfully used in various fields of medicine and
patients prone to fainting on Earth. Orthostatic physiology to assess the state of the basic body
intolerance affects approximately 500,000 Americans functions. Space medicine was one of its first fields of
and can result in significant symptoms. It can also application. To date, a large amount of experience has
hamper a person’s ability to participate in normal been accumulated on its use to assess the functional
activities of daily life. condition of cosmonauts during spaceflight. Changes
The next step is validating the performance of in the activity of the sympathetic and parasympathetic
these garments during recovery from long-duration regulation chains in first hours after falling asleep and
spaceflight in an ongoing study, Recovery of Functional last hours before waking up are determined when
Performance Following Long Duration Space Flight. analyzing the data obtained during sleep. This makes it
Preliminary evidence suggests that these custom- possible to assess to what extent the body was able to
made, gradient compression garments that include rest during sleep, and how much the body replenished
abdominal compression offer relief from orthostatic the functional reserves that were spent the day before.
intolerance and its symptoms.
NASA continues to improve compression garments
that allow astronauts to dress for a more successful
return to Earth.
Sonocard provides a contactless
Innovative Space-based Device recording of physiological signals,
Promotes Restful Sleep on Earth and its use does not require
Interest in the study of nighttime sleep in weightless- attaching electrodes or special
ness has grown since the first steps of space
exploration. Despite many years of investigations, sensors to the body.
researchers still lack experimental data to judge sleep
quality and details of changes in sleep caused by

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