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How to Do Surgery on Mars

— Remote surgery ... in space

MedpageToday

Following is a transcript of this video; note that errors are possible:

Rohin Francis, MBBS: "I'm in big trouble here. I'm in the International Space Station and I don't know anything about knees."

There has been much talk of the societal cost of COVID. Economies across the world devastated, but no one's really talking about one of the most grievous losses of the entire pandemic: me missing my chance at weightlessness.

Yes. Last year I was supposed to go to the European Space Agency for a ride in the infamous vomit comet, or the weightlessness simulator, after one of the parabolic flight instructors at ESA, Neil, very kindly and surprisingly, got in touch. I can't tell you how excited I was for months and months, more than anything in my life. I know what you're thinking, but my wife and kids don't watch this channel -- until, of course, COVID grounded my dreams.

I know a bunch of YouTubers have already made videos from parabolic flights, but I had planned two things that I hoped were going to be a bit more unique: number 1, about the medical research done on the flights -- Neil was going to hook me up with the researchers themselves -- and number 2, to bring you my attempt to breakdance in Martian gravity. I can't do those things, but I can still bring you some juicy space medicine content, starting with space surgery.

When I was studying space medicine years ago, I chatted with a senior NASA person about the need for a doctor on a long-haul mission. It's probable that a trained medical professional will be on a crew to Mars, whenever that may be. But when closer to home -- i.e., on the International Space Station -- it's quite rare for a crew member to be a doctor because the ISS is actually only about 400 kilometers from Earth -- or for fans of imperial measurements, that's 0.0013 light seconds.

Ground-based medics could therefore guide the crew on how to deal with minor medical issues. Frankly, for any catastrophic emergencies, it's easier to just bung the crew member into a Soyuz capsule or a SpaceX capsule and get back to Earth ASAP rather than attempt complicated surgery in space, not least because the space station is not equipped for that. But is there a way that an Earth-based doctor could actually guide an operation in space?

As we've just said, the ISS is too close to need to consider this and Mars is too far for a real-time interaction because of the communication delay, but what about our stepping stone to Mars, the moon? Lunar Gateway is NASA's planned mission to position a space station in orbit around the moon and will probably station astronauts on the surface before we actually go to Mars.

The moon is only around 380,000 kilometers away, or for those unfamiliar with metric measurements -- that's 380,000 football fields if one approximates a football field to a kilometer in length -- and with a communication delay of only 2.5 seconds, which frankly, is about the same as most Zoom conversations I seem to have. This could allow a surgeon to finally join the rest of the world and work from home. I tried some software that might allow this to happen a bit later in the video, but before that, what actually are the problems with surgery in space?

Now, I'm just an amateur space medic these days, but I'm lucky to know several amazing people in the field and you'll be hearing from them in a few planned videos, starting with Eleonor Frost, who did her first degree in physics and medical physics and has undertaken research into space surgery, and then directly went against my advice by going to medical school -- yet another person that I look forward to saying "I told you so" in years to come. Remember, kids, when it comes to doctoring, just say, "No."

What are the main problems related to trying to do surgery in space, and maybe we can start by saying how does a patient behave differently? What are the challenges?

Eleonor Frost: In space, you can essentially be faced with all of the issues that you're faced with on Earth, but there's quite a few different complications that come into play. The first one is the most likely sort of scenario where you'd have to be performing surgery in space, is sort of trauma injuries. That's because things are floating around and you can easily forget that something's picked up speed as you're passing it down to your crew mate, and they get quite a lot of sort of bumps. But if there was to be a big trauma then, that would probably need some kind of surgical intervention, and then...

Francis: So you're talking about somebody throwing a spanner?

Frost: Yeah.

Francis: And just getting whacked in the face. OK.

Frost: Yeah. Exactly, because there is nothing slowing it down so you can kind of lose track of the things that you're sort of passing down the spacecraft, and I think that's what NASA is predicting will be one of the most likely injuries, trauma.

Francis: No clumsy astronauts. OK, noted.

Frost: [LAUGHTER] Or too much playing around in microgravity. Another sort of factor that comes into play with the patients themselves is they're actually already at a hypovolemic disadvantage.

Francis: What Eleonor is referring to here is one of the phenomena that I find most fascinating as a cardiologist and a fan of physiology. Without gravity pulling downwards on our bodies, fluid redistributes to the center of the body, and volume receptors in the blood vessels and the heart interpret this as the body having too much fluid on board, so they tell the kidneys to pee it out, pee out extra fluid.

Therefore, even if the astronauts are replenishing oral fluid, they will still be up to a third more hypovolemic -- i.e, low blood volume -- than they would be on Earth, which is a big problem if you decide to bleed liberally into the air. You already know by now that I enjoy silly names of disorders. The fluid redistribution is officially sometimes called the puffy face chicken leg syndrome.

Frost: So they're already starting at that. What would be on Earth as a class 1 hemorrhage, they're starting at that point, and then if they've got their trauma injury, then they could lose even more blood.

Another thing that comes into play is some of the research they've done has actually found there's increased venous bleeding. They think that's because of the loss of sort of venous pressure from that fluid shift -- again, that comes into play.

Your patients will also already have some cardiac atrophy, loss of bone mass. The immune system will be pretty significantly suppressed, so really not an ideal situation for a surgeon.

Francis: In the TV show "The Expanse," they make a big deal about the lack of gravity -- or more accurately, microgravity -- being problematic for doing surgery and for wound healing. Is that correct?

Frost: Yeah. I would say so. I think wound healing, they haven't actually been able to do that much research on how a wound would heal, because in some of the animal models that they've simulated surgery on they've never had to have that animal recover, so there is very little known about recovery from surgery in space.

Also, a lot of the research has really been conducted on parabolic flights, where you only get a few seconds of microgravity as opposed to research on the ISS. I think how a patient will then recover is a big question, probably one we need to do a bit more research on before we start sending astronauts on long-term missions where we can't get them back in time.

If we're going to Mars, then they could take 3 months to get back, sort of best-case scenario, 3 to 6 months. Whereas the ISS right now, if they really needed to, then they could get to a hospital on Earth within 6 to 24 hours.

Francis: What about from the surgeon's point of view? We just talked about microgravity in terms of wound healing, but what about bleeding? I mean, I imagine that's going to be a complete disaster in space if blood's just flying everywhere.

Frost: Yeah. Absolutely. In the research done, the venous blood is actually not as much of a problem, because that tends to form domes, because the surface tension is really the main force that's acting on it when it's got no gravity to deal with, so you get these venous blood domes.

But in terms of if you get bleeding from an artery, then you start getting these droplet streams, so the blood will be leaving the artery at high pressure and then will start forming droplets, just like when your tap is sort of low and you start forming droplets, and that will just keep going unless you sort of cover it and try and stop the bleeding. Astronauts could lose a lot of blood if they started bleeding in space.

There's also the other issue during surgery that the surface tension will mean there will be blood sort of covering all of the sort of visual fields, so you might get organs that have just covered with a layer of blood that might stop you having the best visualization.

Francis: So you'd need some sort of suction device that may help?

Frost: Yeah. You need a suction device, and then you need to decide where that suction is going to go because you can't just send it into ... the whole ISS is a closed-loop system, so if you send it into the closed-loop system, then you've got bacteria getting in as well.

I think in terms of bleeding as well, you definitely need to isolate the surgical field because if you've got bleeding out into the ISS ... you've seen all those nooks and crannies on the pictures. There'll definitely be issues with cleaning that and try and get rid of all the bacteria, because bacteria have increased virulence in microgravity. They can even grow in 3D, which could be a huge issue for the rest of the crew, but also, if there's an infection, getting into the site as well.

Francis: Bacteria growing in 3D. That sounds like the beginning of a sci-fi movie, doesn't it? What are the kinds of solutions that have been proposed?

Frost: There has been a minimal amount of solutions proposed. A lot of them were really just sort of plastic domes and that kind of thing. But there hasn't been as much research as there probably should be in that field at the moment and most of it has been on parabolic flights, as I said, so not on the ISS itself.

The containment solution is still a question that's yet to be answered, and that's why my dissertation was focused on sort of designing a solution for that kind of thing. It ended up being a kind of glove box enclosure that you could surround the limb or the sort of chest of the patient and then you have a surgical field that's relatively sterile -- but again, would be very hard to keep it very sterile in the atmosphere of the ISS.

Francis: So far I've mostly been thinking about surgery in a weightless environment such as orbiting the moon or the Earth or in interplanetary space, but what about on a lunar or a Martian base?

Frost: There is also a big difference between sort of performing surgery on the way to Mars and then once you're on Mars, because all this microgravity stuff that we've been talking about in terms of how fluids behave with the venous bleeding and arterial bleeding, and that kind of thing, it will be very different on Mars because that's got one third gravity and we don't know how that will affect things.

We also don't know if the astronauts will arrive and they're all going to be deconditioned, so how is the physician astronaut, say, going to be able to perform surgery if he's already got sort of a muscle and bone density loss, and that kind of thing? There's a big difference between surgery in microgravity and surgery in hyper-gravity.

Francis: Yeah. Sort of paradoxically, we know much more about microgravity ...

Frost: Yeah.

Francis: ... than either lunar or Martian gravity. If you want to know more about why astronauts get deconditioned, have a watch of my videos about what happens to the human body in space. Of course, if you had to send a doctor into space and want them to maintain their cardiovascular fitness, might I humbly suggest myself because I literally do cardio for about 12 hours every day?

I've made some really bad jokes on this channel before, but I think that might be the worst. But yes, anyway, it is important to remember that whoever your medic is, they themselves will be affected by all the ravages that space exacts upon the body and so might not be in a position to help others anyway.

Now, regular viewers might know that I'm a bit of a space exploration nerd and particularly love that early generation of astronauts and cosmonauts from the '60s who were some truly remarkable people. You can see in the studio I've got Yuri Gagarin, Valentina Tereshkova. That's Alexei Leonov's leg, and this is James B. Irwin from Apollo 15 on the moon. I used to have two classic photos above my desk that I'm sure you've seen before there for inspiration. I had those for years.

But I think we millennial Zoomers and Gen Xers have got something over the greatest generation. We're children of video games, so it's only natural that we're looking to game developers to assist us in our journey to the stars. The engineers have got Kerbal Space Program, but what about us far more important doctors?

Now, some of you may have seen a video I made using a cardiology simulator last year. The company that made that game, Level Ex, got in touch, and I've been chatting with them about other stuff they do.

I know you've probably seen kind of fun and silly surgeon simulators before, but they've got a super-accurate high-fidelity simulator that runs entirely on the cloud and can be worked on by two different people in real time from opposite ends of the planet, or indeed, opposite ends of the Terran system.

Let me tell you in comparison to the simulation software we get in medicine normally, which makes Minecraft look like Red Dead Redemption 2, the graphics are way better. I asked if I could perform some virtual surgery from space.

Helping me remotely fix this horrendously mangled astronaut knee is Jeff Goldstein, who is an orthopedic surgeon. He's going to talk me through an operation I know nothing about using this virtual technique guide from Level Ex.

Jeff, I'm in big trouble here. I'm in the International Space Station and I don't know anything about knees.

Jeff Goldstein: OK.

Francis: So talk me through what I'm looking at.

Goldstein: Yeah. Well, greetings from Chicago and it's good to talk to you, and so let's replace this patient's knee and get them feeling better. I think I can help you remotely. So you're seeing the patient's knee right in front of you, all right?

Francis: Yeah.

Goldstein: I see you've already made an incision.

Francis: Yeah. It's not too bad. It's a little messy, but ...

Goldstein: [LAUGHTER] It's a little bit long, but it'll give you the exposure you need to ...

Francis: Exposure. It's all about exposure. You can never have too much exposure.

Goldstein: Yeah. I think it's important to see things to do the operation correctly, but let's get these skin flaps out of the way. Why don't you take your retractor? You can put one medially and laterally.

Francis: OK, and let me pull that out of the way.

Goldstein: Perfect.

Francis: OK.

Goldstein: Let's pull them to each side and now you have good full-thickness skin flaps so you can see to make your deeper dissection.

Francis: Oh, that's disgusting. Wow, glistening.

Goldstein: Yeah. It looks great. So why don't you flex the knee up, now that we're looking at the deeper structures, and we'll enter the joint? There you go.

Francis: Right. Oh, there you go. Wow, look at all that movement. So the patella's ...

Goldstein: Yes. I see you've made your arthrotomy and you've everted the patella so you're looking into the joint now. What I would do next is put your cut guide for the distal femur, and you're pushing it right up the canal of the femur.

Francis: Oh, whack it in there. Would I be hammering this in real life, or does that just go in with pressure?

Goldstein: Well, yeah. I mean, you make a drill hole and then you sort of slide it and sort of twist and turn as you push it in, until that piece that you're playing with now sets on the distal femur, and so you're setting the rotation of that cut right now to one.

Francis: To one -- I want it in one, do I? OK. I like turning things up to 11, but oh well. OK, one will have to do.

[LAUGHTER]

Goldstein: All right. Then you're going to slide that down to the end of the bone.

Francis: That's quite satisfying.

Goldstein: All right. Then Rohin, what you're doing now is you're determining how much distal femur you want to cut, so why don't you take 10 millimeters?

Francis: OK, 10. You did it.

Goldstein: I think that's what you set it to and now you'll start your cut for your distal femur. Amazing job. Great job.

Francis: I'm a natural. I'm wasted in cardiology. Unfortunately, I have to tell you that due to postoperative complications and overwhelming sepsis, we lost the patient, so we've ejected him into space. You know, you win some, you lose some. [LAUGHTER] Thanks very much, Jeff.

Goldstein: Sure.

Francis: That was fantastic and I appreciate you talking me through some orthopedic surgery.

Of course, as Eleonor has told us just before, blood would be all over the shop if I really was on a space station, so we might have to employ that magic glove box thing, which would be an absolute pain.

Obviously, that's a pretty basic demo at the moment and I should say it's not been developed with space in mind. This was my idea to frame it like this, so the demo they gave me isn't quite the most realistic injury that an astronaut is likely to suffer.

But let's assume, just suspend your disbelief for a moment, that I, a cardiologist, am performing a knee replacement in space because for some reason we sent an old man with bad knees up there. Hang on, that's my TikTok bio.

OK, so perhaps I'm operating on myself like the famous Leonid Rogozov. But then, again, loss of bone density is one of the main problems in low gravity so perhaps it isn't that unrealistic at all. Actually, I want to add something about Rogozov that is related to space.

Now, I know most of you will have probably heard the amazing story of the young Siberian surgeon who got appendicitis in Antarctica and cut his own appendix out because there's no shortage of YouTube videos about it, but most only go skin deep.

Reading his account of the operation is not only kind of hilarious because his squeamish assistants were way more scared than he was, but it also revealed his meticulous nature, having prepared for every eventuality during surgery, including telling his colleagues what to do if he passed out.

Of course, remote missions like that are where we've learned a huge amount about how to prepare for space exploration, but you might not be aware of Rogozov's reception back home in the Soviet Union. He did his DIY operation only 18 days after Yuri Gagarin became the first human in space and they were also the same age, 27. They both became national heroes, ideals of the Soviet State, young, handsome, overachievers, but made of really tough stuff.

One of his legacies manifested when a friend of mine from medical school became the in-house doctor at the British base in Antarctica a few years ago and had to have his appendix prophylactically removed before going so there would be no repeat of this scenario. Now, that friend also had to be airlifted out early because there were real concerns that his team leader and he would kill each other, but that's another story.

Rogozov is actually only number two in the history of extreme self-surgeries because number one is occupied, I love this story, by President of the International Mothers Are as Tough as Nails Organization, Inés Pérez, a Mexican villager from Oaxaca who performed her own Caesarean, metal as [BEEP].

Bottom line, space is a terrible place for human physiology and the idea of actually performing surgery in space is just horrendous. Doing it on the moon or Mars is marginally less scary but still a terrifying thought for many other reasons, but one we do need to start thinking about as we hopefully move into a future as an interplanetary species.

If you're interested in space-related content, make sure you're subscribed because I've got a few other ones planned, including one about a rather unusual job advert.