Planetary Defense, Deep-Space Healthcare, and the Future of Medicine and Humanity: A Conversation With Robert Thirsk

INTERVIEW BY IVAN DURAN

HHPR Senior Editor Ivan Duran interviewed Robert Thirsk, OC, OBC. Dr. Thirsk received degrees in Mechanical Engineering, Medicine, and Business Administration from the University of Calgary, MIT, and McGill University. He has flown on two spaceflights: a mission aboard the shuttle Columbia, and an expedition aboard the International Space Station. Dr. Thirsk continues to promote an economy based upon exploration, innovation, and lifelong learning.

Ivan Duran (ID): Few people are physicians, fewer people are astronauts, and even far fewer people are physician astronauts like you. Why did you choose to become a physician? Did you ever envision yourself taking the leap into space, and how did you make the transition toward also becoming an astronaut?

Robert Thirsk (RT): The people, places, and events of my childhood nurtured my passion for exploration and influenced my choice of an educational path and career. The 1960s and 1970s were amazing decades. We had inspirational leaders with global outlooks who believed that we do things not because they are easy, but because they are hard. Society was advancing fastly on numerous fronts including science, technology, and education. In 1961, the first human ventured into space, and only eight years later two people walked on the Moon. This was mind-blowing to an impressionable boy like me!

My fascination with spaceflight was reinforced by TV programs like Star Trek and movies like 2001: A Space Odyssey. They showed me what space exploration missions could look like and inspired me to go where few had gone before.

A university professor who was aware of my ambition for a space career advised me to pursue medical training following completion of my engineering degree. This was surprising but sage advice. Medical school augmented my technical orientation with clinical knowledge and skills. I was selected to the Canadian astronaut program a couple years after completing my medical degree.

ID: How is space medicine different from medicine on Earth? With that in mind, do you envision space medicine as having advantages over practicing medicine on Earth?

RT: There are several differences between the practice of medicine on Earth and in space. Patients with illness can be described as people who live in a normal Earth environment but who have abnormal physiology. Astronauts, on the other hand, are people with normal physiology (indeed with high levels of physical fitness) who live in an abnormal environment. It is this abnormal space environment (weightlessness, ionizing radiation, isolation, and confinement) that alters astronauts’ physiology, thus requiring the development of medical countermeasures.

The goal of sending people farther into space (to the Moon, asteroids, and Mars) and extending the duration of missions will challenge the current capabilities of space medicine. Medical evacuation from deep space to Earth of a seriously ill crewmember will no longer be an option. Due to speed-of-light communication latencies, real-time consultation with ground-based medical teams in urgent situations will no longer be possible. Spaceflight crews will need to become more autonomous and the role of the onboard crew medical officer (CMO) will need to expand. Future CMOs should be broadly experienced clinicians, with qualifications in space and emergency medicine as well as some surgical and psychological training.

An artist's concept depicts astronauts and human habitats on Mars. Courtesy NASA.

The limited volume, mass, and power allowances of deep space vehicles mean that the size and capability of the onboard medical care facility will be limited. It will not be a well-outfitted hospital. Nevertheless, the facility will need to monitor crew health and support a spectrum of medical and surgical interventions.

ID: What are some in-flight and long-term effects of space travel on the human body? What major advances have been made to safeguard the health of astronauts and other spaceflight crew? How have these advances contributed to medicine?

RT: Space is a harsh environment in which to live and work–characterized by isolation, confinement, vacuum, extremes of temperature, high fluxes of ultraviolet and ionizing radiation, and weightlessness. It seems that everything about space is trying to kill us!

The Advanced Resistive Exercise Device (ARED) aboard the International Space Station is a sophisticated machine that simulates the use of free weights. All major muscle groups can be trained. Courtesy NASA.

While spacecraft and spacesuits provide protection from some environmental effects, astronauts must still adapt to the effects of weightlessness. All organ systems are affected, but some seem to be impacted more than others. Muscles and bones atrophy and lose strength in the absence of gravitational loading. The atrophy is generalized, but most affected are the postural muscles and weight-bearing bones–those muscles and bones that maintain our bodies upright in a gravitational field.

It is essential that astronauts maintain muscle strength throughout flight in order to perform EVAs (space walks) and other strenuous endeavours. Since the success of missions can be jeopardized by astronaut incapacity, a variety of countermeasures have been developed over past decades, encompassing pre-flight physical conditioning, dietary supplements, pharmacological agents, and postflight rehabilitation.

The primary musculoskeletal countermeasure is in-flight exercise. Astronauts aboard the International Space Station spend 1.5 hours exercising each day–45 minutes of aerobic exercise and 45 minutes of muscle resistance. The resistive exercises are intense and focused on loading of the lower extremities and back. While we can’t completely prevent spaceflight deconditioning, daily exercise can minimize the loss of mass and strength.

ID: What are some of your favorite and most memorable experiences as a researcher and physician astronaut?

RT: Preflight training and my two space missions were challenging–they agreeably took me to my physical, mental, and emotional limits. When performing difficult tasks like survival training, EVA, robotics, rendezvous, research, and system repairs, it was reassuring to do so with crewmates who were skilled, conscientious, and inspiring. They elevated my performance. I was privileged to serve in space with the best professionals.

Besides spending time with crewmates, I also enjoyed looking out the spacecraft window. I spent many memorable hours gazing down on our home planet. It is gloriously beautiful. Deserts come in a hundred shades of colour. A thunderstorm is a powerful phenomenon to behold. Viewed from above, mountain ranges, erupting volcanoes, and ocean reefs are mesmerizingly majestic.

Flying about like Superman—how cool is that!

And I fondly recall the joy of soaring throughout the space station. It was the fulfillment of a childhood fantasy to fly like Superman!

ID: Health Beyond was recently published by the Canadian Space Agency. May you tell us about this report by the Advisory Council on Deep-Space Healthcare that you chaired and co-authored?

RT: The Advisory Council on Deep Space Healthcare was tasked by the Canadian Space Agency to provide recommendations on a meaningful role for our country in the upcoming exploration of the inner solar system.

Galaxy Cluster (Health Beyond cover image) by Margaret Nazon. Courtesy of Glenbow Museum.

Our national healthcare community is globally respected for its capabilities in clinical diagnostics, practitioner training and simulation, as well as in emerging technologies such as AI, digital health, and remote medical robotics. Accordingly, our Advisory Council recommended that Canada lead remote healthcare delivery to deep space astronauts on behalf of international partners. This would be a critical role since maintenance of the health, well-being, and performance of astronauts will be directly tied to mission success.

A national investment in remote healthcare delivery could also bring socioeconomic benefit. Improvements in national healthcare access, equity, and outcomes are urgently needed–especially for underserved communities and for Indigenous peoples. While urban Canadians enjoy world-class medical care, citizens living in remote regions do not. Morbidity and mortality rates among northern Canadians are well above the standards of OECD countries.

The Health Beyond report expresses the Advisory Council’s enthusiasm for a healthcare initiative that could enable deep space exploration by international astronauts and enhance the health of isolated populations in the far North. Canada could become the global leader.

ID: At times it seems that space tourism–an industry that was mentioned in Health Beyond–eclipses developments in deep-space exploration. Moreover, there is opposition to using both public and private resources for space projects such as deep-space healthcare because there are many health inequities on Earth. What are the benefits of space missions to medicine and healthcare on Earth?

RT: The space program has spun off many terrestrial applications. In fact, if there is one sector of society that has particularly benefited from dual-use technologies, it is healthcare. For example, past research and development (R&D) investments in space robotics are benefitting patients today. The University of Calgary partnered with the company that built the robot arms for the space shuttle and the International Space Station to develop neuroArm–a microsurgical telerobotic system. neuroArm incorporates the control algorithms, haptics, and vision system of the space manipulators. The resulting surgical robot is as dexterous as a neurosurgeon’s hand but more precise and tremor-free, thus allowing surgeons to perform intricate microscopic neurosurgical procedures. The robot has successfully treated many patients with hydrocephalus, brain tumours, and vascular malformations. There are hundreds of other space applications that have similarly advanced the delivery of healthcare on Earth.

Adoption of space-based technologies cannot cure all that ails a country’s healthcare system–the social determinants of health have a greater bearing on outcomes. Nevertheless, training and tele-mentoring approaches used to support crew medical officers could be translated to empower physicians and nurses working in isolated communities. Equipping local clinics with autonomous, point-of-care and patient-centric technologies as well as virtual care support has the potential to build up community-based clinical capabilities, and reduce medevac costs.

ID: Don’t Look Up, a satirical film of governmental, public, and media indifference to planetary destruction was all over the news and propelled the conversation about the real possibility of a comet colliding with Earth. In November 2021, NASA launched the first ever spacecraft test to change the course of an asteroid in space with the overarching goal of defending Earth against threats from space. What do you think about these programs? Should more be done to develop them? What other threats are we currently unprepared for?

Credits: NASA/Johns Hopkins Applied Physics Lab

RT: I was pleased by the launch of NASA’s Double Asteroid Redirection Test (DART) spacecraft last November. If its demonstration mission is successful, it will reassure us that the trajectory of a threatening asteroid can be changed. The European Space Agency will launch a similar mission called Hera in 2024.

While there is no known asteroid that will collide with Earth in the next 100 years, I agree that we need to enhance our asteroid monitoring and averting capabilities. If a large asteroid ever impacted Earth, it could be catastrophic for the survival of humanity and nature.

Reflecting more expansively, I wonder if the space program’s time-honoured approach to astronaut training could be adapted to improve emergency preparedness and response on Earth. Space missions are enormously difficult to conduct. The training that I received prepared me well to deal with many contingency situations (possible bad days in space) that I might encounter. Rigorous, realistic, and relentless simulator-based training was the cornerstone of my preparation.

As a former astronaut, I was dismayed by the world’s response to the COVID-19 outbreak. While some jurisdictions sprang into action and implemented effective countermeasures against the virus, many did not. In the outbreak’s early weeks, many leaders were uncertain, tentative, and conflicted. They seemed unprepared; the scale and severity of the outbreak catching them by surprise. Consequently, in several regions, viral proliferation was not well contained.

Comprehensive simulations of a pandemic run repeatedly during preceding years could have validated emergency plans and better prepared the response teams. Simulations that modelled the interactions across societal systems could have identified deficiencies in our healthcare, supply chain, and manufacturing systems. Once these vulnerabilities had been exposed, they could have been mitigated through new policies, improved procedures, and continuous innovation.

The next global crisis may not be another viral outbreak. It could be an asteroid strike, nuclear accident, act of terrorism, financial depression, major earthquake, or solar storm. While the likelihood of any one of these events happening in a given year is small, its impact when it does happen could again be catastrophic. In the spirit of building back better, I advocate for investment in the kind of emergency preparedness and response training we do in the human spaceflight program. The benefits would be significant.

ID: What are your thoughts on biostasis–"a novel approach that could reversibly and controllably slow biological systems to stabilize and protect their functional capacity until medical intervention is possible"–being leveraged for deep-space healthcare and medicine in general? What about the potential of cryonics for prolonged space exploration missions?

RT: I don’t know much about biostasis but have seen the concept depicted in movies like 2001: A Space Odyssey and Aliens. Slowing the metabolic rate of astronauts could make exceedingly long missions to extremely distant places more feasible. Induced biostasis of the crew could theoretically cut down the quantity of consumables and supplies, reduce the size of the spacecraft habitat, and save mission costs. The hibernation process in bears may be worth researching as a model for biostasis in space. Apparently bears exit their dens in spring with only marginal loss of muscle and bone mass.

A more pressing need, in my opinion, is the development of better rocket engines to speed up travel within the inner solar system. Ion propulsion systems, for instance, could get astronauts to Mars faster. The thrust from an ion thruster is low compared to a chemical rocket, but it can be operated continuously and the spacecraft can therefore build up large velocities. This would reduce travel times to interplanetary destinations.

ID: There is an increasing healthcare professionals shortage–especially in rural areas. What could be done to solve this crisis? Does that shortage also extend to missions in space?

RT: The surgeons, physicians, and nurses who serve in isolated communities are remarkable professionals–the decathletes of clinical medicine. Their comprehensive knowledge and highly honed skills enable them to diagnose and manage a broad range of clinical cases. When faced with uncertainty and ambiguity, their MacGyver-instincts allow them to devise novel solutions.

But there are too few practitioners to staff all rural and remote communities. The work of remote practitioners is demanding, stressful, lonely, and can lead to burnout. Consequently, the gap in access by patients to local care, particularly specialized care, is widening for remote communities compared to urban centres.

Approaches, technologies, and infrastructure must be enhanced to better support these essential healthcare providers in their communities. Innovations in AI-enabled diagnostics and therapeutics offer hope of improved patient outcomes. Advancements in contextual training, simulation, and tele-mentoring for local practitioners could bolster mental and professional resilience. Improvements in communication and transportation infrastructure would enable continuous and reliable connections with supporting consultants at tertiary care centres. Collectively, these measures–not unlike those required for future deep space crew medical officers–could improve the recruitment and retention of practitioners to communities that sorely need their services.

ID: What do you consider as the two greatest threats to planetary health? If it was up to you, how would you avert them?

RT: The view of Earth from space is personally transformative. Viewed from afar, our marbled-blue planet is alone for hundreds of millions of kilometers, surrounded by nothing but void. Within our solar system, Earth is a tiny, solitary oasis of intelligent life.

The two greatest threats to planetary health are nuclear annihilation and climate change. Survival of our species is not a sure thing. The global rhetoric and recent aggression between nations worries me. Considering the snail-paced progress that civilization has made over the last millennia at great sacrifice, wouldn’t it be tragic and irresponsible if humanity ceased to exist at our own hands?

In the coming decades we might detect life elsewhere in our galaxy. That would be exciting. But it very well could be that we are alone; that we are the only intelligent life in the universe. Realizing the vulnerability of life on our home planet makes me more diligent in preserving our existence.

ID: Would you like to comment on anything else? We highly appreciate your insights.

RT: Everything that I have accomplished as an astronaut has been done on the basis of collaboration–collaboration across disciplines, across cultures, across international borders.

The best thing about the human spaceflight program is that it is international. Nations come together to pursue a common vision; to do great things in the areas of discovery, creativity, and innovation; to inspire society to pursue audacious dreams.

I believe that the visions that unite nations are more powerful than the issues that divide us; that social, cultural, economic, and political barriers can be overcome to stretch humanity’s capabilities. I believe that the peaceful exploration of space is critical; that the Earth is the cradle of humanity; and that someday our civilization will migrate to interstellar destinations.

In a frustrating, perplexing world, cooperative human spaceflight can be a common ground, a beacon of hope, an oasis of sanity. It can maintain an open dialogue between partner nations that are experiencing diplomatic discord.

Earthrise photo from the Apollo 8 lunar mission. Courtesy NASA.