The new focus on manned missions to the moon and Mars presents countless pressing challenges, including keeping humans alive in hostile environments. What happens when an astronaut or space tourist has a cardiac emergency millions of miles from the nearest hospital?
To help prepare humans for safe long-duration space travel, a research team based at Concordia has developed a new high-fidelity simulator that models how blood flows (hemodynamics) in reduced gravity environments.
Their system is based around a modified mannequin equipped with a 3D-printed cardiovascular system, including a heart, heart valves, artificial vessels and fluid-filled loop that mimics blood flow. After testing, it was found to have successfully reproduced key pressure patterns seen during effective CPR on Earth and generated consistent blood flow under both normal gravity and hypogravity conditions. It also revealed measurable differences in how the body may respond in reduced gravity.
"We saw significant increases between the different types of arterial pressure at hypogravity and at Earth gravity: systolic, diastolic, mean arterial pressure and pulse pressure were all higher. This validated our high-fidelity heart simulator," says lead author Zoé Lord, BSc 2019, BSc 2022, now pursuing a PhD at Queen's University.
The study was published in the Nature journal npj Microgravity.
High-fidelity CPR simulator mannequin. Photo courtesy Zoé LordThe challenges of resuscitation in space
The most common cardiopulmonary resuscitation (CPR) methods may not be effective in space environments, given the effect reduced gravity has on blood flow and lack of bracing, among other factors. While several space-adapted CPR techniques have been proposed, none have been fully validated using internal physiological measures.
Previous studies have focused mainly on external metrics, such as compression depth and rate. These do not fully capture whether enough blood is circulating to sustain vital organs, making it difficult to determine which techniques are most effective.
"Most issues on CPR in space are oriented towards the health provider rather than the patient," says Lyes Kadem, a professor in the Department of Mechanical, Industrial and Aerospace Engineering and the director of the Laboratory of Cardiovascular Fluid Dynamics. "We see this system as a bridge that will help space medicine practitioners investigate the hemodynamics of blood flow."
Zoé Lord and Christian Andrade, front, at work in hypogravitySimulated space conditions
The system was developed and tested in labs at Concordia and on board a Canadian government-owned Falcon 20 jet designed specifically for space science experiments. The researchers conducted their experiments during brief moments of hypogravity during two parabolic flights over two days.
Before the flights, the automated simulator was attached to a frame and fitted above the modified mannequin. During the brief moments of hypogravity, it delivered accurate compressions to the heart's ventricle.
"That would begin the process of moving the fluid, a blood analogue, through the carotid artery to the brain," Lord says.
Sensors were attached to strategic parts of the mannequin, including the carotid artery, which is the main artery bringing blood from the heart to the brain. These sensors were able to track pressure changes in real time, allowing the researchers to see how effectively compression was moving fluid through the body.
Team member Christian Andrade, BSc 2026, collected and interpreted the data in real time under hypogravity conditions.
More realistic models to come
Lord points out that the existing version is only the first of what she hopes will be multiple iterations.
"We want to make future models more physiologically realistic compared to the first one," she says. "We hope to integrate a spine, a rib cage and a more complex thoracic cavity, since the heart shrinks when a person is in space. We also hope to improve the tubing structures and improve the instrumentation.
"The ultimate goal is to get our mannequin aboard the International Space Station to measure what happens in actual space flight conditions."
Lawrence Leroux of the Université de Montréal contributed research to this article.
This study was funded by the National Research Council of Canada.
Read the cited paper: "A high-fidelity simulator for evaluation of hemodynamic response during cardiopulmonary resuscitation in hypogravity environments"
