Cardiac arrest in space – chest compression machines could improve astronaut survival

Jack Loughran Wed 27 Aug 2025

Collected at: https://eandt.theiet.org/2025/08/27/cardiac-arrest-space-chest-compression-machines-could-improve-astronaut-survival

A type of automatic chest compression is more effective for carrying out CPR in space than the ‘handstand method’ currently recommended in emergency protocols, researchers have said.

Earth-based chest compressions during CPR are based on the rescuer’s weight, which does not exist in microgravity. Therefore, alternative methods such as the handstand, reverse bear hug and Evetts-Russomano methods have been developed. But until now, none of them have been shown to reach the depth standards needed for effective chest compressions. 

Researchers from the University of Lorraine in France tested three automatic chest compression devices during a parabolic flight that replicates the effects of microgravity for short periods of time. They found that a standard mechanical piston CPR had the highest median compression depth during the flights and could improve the chances of resuscitation for astronauts suffering from heart problems in space.

While there have been no confirmed cases of astronauts suffering a heart attack in space so far, there have been instances of heart-related medical issues. James Irwin experienced several heart-related events soon after coming back from the Moon as part of Apollo 15. And in 1997, cosmonaut Vasily Tsibliyev developed a heart arrhythmia while on board the Mir space station and needed to take heart medication and tranquillisers.

The number of people flying to space has been on the increase in recent years, with the 750th person leaving the Earth’s atmosphere during a suborbital flight with Blue Origin in June. With older space travellers now taking flight, such as 90-year old William Shatner in 2021, and the strains that space travel put on the human body, the possibility of a cardiac arrest occurring in orbit is becoming increasingly likely.

Nathan Reynette from the cardiology department at the University of Lorraine said: “We tested different ways of giving chest compressions aboard a ‘flying laboratory’ which recreated the microgravity conditions that astronauts experience in space. 

“Use of a particular type of automatic chest compression device was the only method that gave the depth that is recommended by international resuscitation guidelines to keep blood flowing to the brain in a real-life cardiac arrest. We hope that our findings will be incorporated into the next guidelines for treating cardiac arrest in space.” 

Reflecting on whether future space missions will take automatic chest compression devices in their emergency medical kit, Reynette added: “It will be up to every space agency whether they want to include automatic chest compression devices in their emergency medical kit. We know they have other considerations beyond effectiveness, such as weight and space constraints.

“While cardiac arrest is a high-danger event that could even terminate a space mission, it is a relatively low risk for now. Most astronauts are young, healthy and physically fit individuals who have intensive medical monitoring, including scanning for chronic heart disease, before going into space. Nevertheless, longer-lasting space missions in future and space tourism could increase the risks of a medical emergency occurring.”