An astronaut’s mystery illness could change the way NASA plans future missions - CNN

Five months into his fourth International Space Station mission, veteran NASA astronaut Mike Fincke was having dinner the day before a routine spacewalk. Suddenly, he found himself unable to speak. The episode in January lasted just 20 minutes and while Fincke felt no pain, he became agitated.

“It was completely out of the blue. It was just amazingly quick,” Fincke recently told the Associated Press.

“My crewmates definitely saw that I was in distress. It was all hands on deck within just a matter of seconds,” he said.

Fincke’s fellow astronauts and a series of emergency protocols kept him safe, but NASA still made an unprecedented move: The agency cut short the SpaceX Crew-11 mission, returning Fincke and three of his fellow astronauts to Earth a month early and leaving the station staffed by only three people. Now, this event might play a role in how future missions are designed.

Jared Isaacman, NASA’s administrator, said in a post-splashdown news conference that the early return was due to a “serious medical condition.” He added that while astronauts receive extensive medical training, there are circumstances in which the option to come home is the best one, and that’s why that possibility is built into the agency’s flight plans.

“This is what we trained for. It’s built in our planning. It was executed very well,” Isaacman added. “We will capture any relevant lessons learned to inform preparations for subsequent missions.”

But as NASA pursues long duration missions farther into space, what if it’s no longer as simple to just come back?

SpaceX Crew-11 returned to Earth safely on January 15, eight days after the episode — meaning this wasn’t an emergency evacuation, which would have unfolded in a matter of hours. Still, Fincke was the first in over 290 visitors to the ISS to return home early due to a health concern.

NASA hasn’t revealed many details about the incident, which tracks with its usual approach of protecting astronaut privacy and keeping all medical matters confidential. Even when studies analyze specific aspects of astronauts’ health, the research typically doesn’t disclose identities. Fincke later revealed the early exit was due to concern for his health, without disclosing any formal diagnosis, though he told the Associated Press the symptoms were likely space-related.

And while the response to his situation was unique, Fincke is far from the first person to experience a medical issue in space.

The strong forces and the weightlessness experienced during space travel have a variety of effects on the human body. NASA has been studying these effects for over 50 years and groups them into five key hazard areas: radiation, isolation, distance, microgravity and hostile environments. These forces can cause ailments including bone and muscle loss, cardiovascular issues, immune dysfunction and vision impairment.

One key process that weightlessness affects is blood flow. Away from Earth’s gravity, blood and other body fluids are pushed up toward the head from the legs and torso, causing swelling in the upper body. In 2019, a study conducted on 11 healthy astronauts — nine unidentified men and two women with an average age of 46 — revealed that six of them suffered from stagnant or reverse blood flow, one experienced a blood clot and another a partial blood clot.

“The environment of space can be disabling, and the strains of space can impact virtually every aspect of your body,” said Dr. Farhan Asrar, an associate professor at the Faculty of Medicine of the University of Toronto. “Space affects your muscle mass, your bone health. We know that fluid shifts have been causing a lot of issues as well.”

He added that certain blood flow issues could also potentially lead to a temporary lapse of speech. “There is something known as a TIA, or Transient ischaemic attack, which is basically a brief episode of a neurological dysfunction, usually due to the blood flow to the brain being interrupted,” Asrar said. “It tends to resolve by itself and not leave any kind of permanent damage.” TIA symptoms can also include dizziness, confusion and loss of balance.

It’s not clear, however, whether Fincke experienced any additional symptoms or if his condition had anything to do with blood flow. The crew used the space station’s ultrasound machine to assess Fincke, likely with guidance from mission control.