A high-tech sleeping bag that can solve the astronaut’s crushed eyes problem

Scientists have developed a high-tech sleeping bag that could prevent vision problems that some astronauts experience while in space.

In zero gravity, fluids float inside the head and over time squeeze the eyeball. It is considered one of the most dangerous health problems for astronauts, and some experts believe it could interfere with flights to Mars.

The sleeping bag balances the fluid in the head and transports it to the legs, controlling the increase in pressure. It was developed by Benjamin Levin, professor of medicine at the University of Texas Southwestern Medical Center at Dallas. Levin is working to transfer equipment to the International Space Station (ISS).

NASA, the US space agency, has reported vision problems in more than half of the astronauts who have been on the ISS for at least six months. Some had difficulties with vision from afar, with reading, and they needed help in conducting experiments on a space mission.

“We do not know what the consequences of a longer space flight, such as a two-year operation on Mars, could be,” said Levin, who is also the director of Institute of Physical Therapy and Environmental Medicine.

“It would be a disaster if the astronauts were seriously compromised to the point where they could not see what they were doing, which would jeopardize the mission.”

In 2005, astronaut John Philips began his mission to the ISS with normal vision, also called 20/20 vision, and returned six months later with 20/100 vision. A normal eye could see up to 100 meters.

Others had less serious versions of the problem. On Earth, gravity pulls body fluids down every time a person gets out of bed – this is called “unloading.” But in space, low gravity allows half a gallon of bodily fluids to build up in the head, putting pressure on the eyeballs.

This can lead to a condition called space travel neuro-ocular syndrome. (spaceflight-related neuroocular syndrome) or SANS, its abbreviation in English. This, in turn, can lead to progressive flattening of the back of the eyeball, swelling of the optic nerve, and impairment of vision.

“The pressure under zero gravity is always less than the pressure under gravity. But it is not as low as when you are standing. NASA astronauts cannot stand during the flight, ”Levin told BBC News.

constant pressure

Although the pressure on the brain of a person lying on Earth is slightly higher than that of a person lying in space, astronauts experience constant pressure and cannot relieve it by standing upright.

“They never had the opportunity to ‘unload’ (fluid flow) from the brain. So we asked, “Can we reintroduce the gravitational gradient”? – says Levin.

The sleeping bag wraps around the person’s waist, covering the lower body with a strong frame.

The suction device, which works on the same principle as a vacuum cleaner, creates a pressure drop that displaces liquid towards the feet. This prevents the accumulation of fluid in the brain and the “crushing” of the eyes.

Before using this technology, some questions need to be answered, such as how much time astronauts should spend inside the device each day.

“Should everyone do this, or just people who are predisposed to developing SANS? Do you need to do this as soon as you get into space, or can you wait to see if your vision changes? ” – illustrated Levin, talking about the still unanswered questions. “This sort of thing has yet to be determined.”

But Levin says the creation of the sleeping bag means SANS can no longer pose a health hazard in NASA’s future mission to the Red Planet.

People who have had cancer and have survived have played a crucial role in figuring out the causes of this disease. The volunteers still had access to the head, which was used to administer chemotherapy drugs, and this allowed the scientists to measure the pressure in the brain as they spent a few seconds in zero gravity flight simulators.

A dozen more volunteers tested the technology itself. Scientists took measurements while lying with and without a sleeping bag. The researchers found that although three days of lying was enough to slightly reshape the eyeball, no changes occurred when using aspiration technology.

A team of researchers at the Southwestern Medical Center previously discovered that microgravity causes the heart to contract in space, potentially causing a condition called atrial fibrillation, a type of cardiac arrhythmia.

It is possible that a sleeping bag may also help control abnormal blood flow, which increases the risk of mild irregular heartbeats. Research on this has been published in the academic journal JAMA Ophthalmology.