If humans are to visit distant worlds, even if it is Mars, it is important to understand the effects on the mental and physical health of astronauts caused by prolonged space travel. Some effects like losing muscle mass and brittle bones that arise as the astronauts are not under gravitational effect are known. But, there are still other unknown adverse effects of microgravity or even cosmic radiation.
In a new study published in the JAMA Network Open, scientists have found that astronauts who spend an extended time in space can experience blood clots and reversed blood flow in their upper bodies.
Researchers analyzed data from periodic ultrasound tests of 11 healthy astronauts who had spent an average of six months aboard the International Space Station and made an upsetting discovery.
By their 50th day, aboard the ISS, seven astronauts were found to have stagnated or reversed blood flow in their left internal jugular vein. One of the astronauts developed a clot while another was found to have a partial clot in the internal jugular vein.
The jugular veins are important blood vessels running through the neck that carry deoxygenated blood from the head to the heart. Thus, a clot will likely have adverse effects on an astronaut’s health. But, scientists and doctors can find a treatment or a prevention method for the complication caused due to microgravity.
Michael Stenger, the senior author of the study told the NBC News, “We did not expect to see stasis and reverse flow. That is very abnormal. On Earth, you would immediately suspect a massive blockage or a tumor or something like that.”
Image Credit: NASA/ISS