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Mostly dead is slightly alive

2025/6/16
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Unexplainable

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Adam Richman
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Bird Pinkerton
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Bird Pinkerton: 死亡的定义随着医疗技术的发展变得越来越模糊。过去,心跳和呼吸停止是判断死亡的标准,但现在有了呼吸机等技术,即使大脑受损的人也能存活。因此,医学界引入了脑死亡的概念,即不可逆转的脑损伤。然而,在某些特殊情况下,例如深低温循环停止术,患者可能既没有脑活动也没有心跳,但仍然存活,这给死亡的定义带来了新的挑战。 Adam Richman: 作为一名体外循环灌注师,我经常在心脏手术中使用深低温循环停止术。这种技术通过降低患者的体温来减缓其代谢过程,甚至可以使脑电活动停止。在这种情况下,患者实际上处于一种介于生死之间的状态,他们的生命完全依赖于心肺机的支持。这让我对死亡的定义产生了深刻的疑问:当大脑和心脏都停止工作时,但身体仍然有血液流动,这是否意味着患者已经死亡?

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After graduating from high school, Anthony needed a plan. He loves playing video games, but that doesn't cover rent. So he took a job at Amazon packing boxes. He heard about their free skills training programs to boost his pay. Now Anthony is a software developer for Amazon. With a bigger paycheck, he upgraded his computer system at home. With his new skills, he's developing a video game in his free time.

It's an interesting time for business. Trade policies are in flux and cash flows are tighter than ever. You need total visibility into what's happening under the hood of your company and you need it all in one place.

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I've been thinking about this question, right? Are there different ways to be dead? For years at this point. Basically ever since Bob Trug, this bioethicist, asked it. I spoke to him for an episode that we did a while back called Redefining Death. And he told me, essentially, that death used to be relatively simple. Up until about the 1950s, there was no confusion about what death meant.

You just kind of knew it when you saw it. Your heart had stopped. You had no breathing, stiff body. And you were, you know, blue or gray. You were probably dead. But then, in the 20th century, as we started inventing new technology, the line started to blur more.

You had things like ventilators, which kept patients alive even if their brains were too injured to tell their lungs to breathe. But when the ventilator was used and you could breathe for them, they went on and lived and lived and lived. Their hearts were still pumping blood through their bodies, but their brains weren't working right. Eventually, the medical community had to define a new kind of death. Not just the "your heart has stopped" and "you're cold and stiff" version, but something else.

What we call brain death. Irreversible brain damage, where a brain and a brainstem stop functioning and stop sending signals. The person will never regain consciousness and will never breathe on their own again. That might seem straightforward, but as we showed in the episode we made a while back, there's a lot of nuance to it. Yeah, that's why I reached out. You know, this is just one big...

Great. Adam Richman is one of my favorite kinds of people, the people who listen to Unexplainable and then write in about episodes. He heard this episode about redefining death, and he emailed us to share his very specific perspective on both medical technology and the definition of death. Death is unfortunately part of cardiac surgery.

Adam is a perfusionist at the Mayo Clinic in Minnesota. So as a perfusionist, we run the heart-lung machine during cardiac surgery. This heart-lung machine lets doctors operate on parts of the heart by basically stopping the heart and rerouting the blood through a machine. It oxygenates the blood and it pumps it back through the body. But as Adam told me...

It also made him think long and hard about what it means to be brain dead. We don't understand very well neurologically what's going on. This is Unexplainable. I'm Bird Pinkerton. And on today's show, hundreds of you Unexplainable listeners, you have written in over the years. So for this episode, we are handing over the mic to one of you, Adam Richman. And he will bring us to the edge of death and then back again.

You're going to be part of a really see how the sausage is made. Yeah. Because we're up to antics over here. Yeah. So you reached out to the show back in like 2022 because we made this episode, right, called Redefining Death. And I'm curious, kind of given your day to day experience,

What was it about that episode that kind of like struck a chord with you? So it reminded me of a lot of the surgeries and procedures that we do with the aorta specifically. That's like the big artery in the heart, right? Yep, that's the big artery coming straight out of the heart to carry all the oxygenated blood to the rest of the body. And if there is disease of the aorta, then...

That kind of presents a challenge because, you know, there's blood flying up there, but that's also the area where they need to fix. So in order to do that, we use a technique called deep hypothermic circulatory arrest. Okay, deep hypothermic. Deep hypothermic. Circulatory arrest. Circulatory arrest. So like very cold. Hypothermia is like being cold. Very, very cold air.

Exactly. That's exactly what it is. Okay. You, you know, for instance, hear about a child that's fallen through the ice in the winter and their heart stops and everything. And, you know, they're brought to the hospital and warmed up again. They're essentially reanimated. So it's very similar to that. So as we change the temperature of the blood, that changes the temperature of the patient. Okay.

So you're using the machine basically to like pump frigid blood, not freezing obviously, but like pump frigid blood through their body to cool them all the way down? Yep, that's exactly it. Okay, and what does that do? So we know about a process called the Q10 effect. Essentially what that is, is that as our body temperature decreases...

Our metabolism also decreases. Okay, so you're just literally slowing down. Exactly. You're slowing down every single metabolic process in the body. So how cold do they get? Like, how much slower is their body going? So, and this is why I reached out to you guys, because we'll actually monitor their EEG, their brain activity, the electrical activity in the brain,

And it will actually flatline and stop. Oh, my God. So are you, by our medical definition of brain death, are you temporarily killing them? Or are they, like, temporarily dead? Yeah.

I can't say yes for sure. Their body's still functioning. It's just extremely slow. But there's no brain activity. There's no cardiac activity. So the only reason that they're actually still alive is because we're actively pumping blood. After the break, how to bring someone back to life after you have turned their brain off.

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After graduating from high school, Anthony needed a plan. He loves playing video games, but that doesn't cover rent. So he took a job at Amazon packing boxes. He heard about their free skills training programs to boost his pay. Now Anthony is a software developer for Amazon. With a bigger paycheck, he upgraded his computer system at home. With his new skills, he's developing a video game in his free time.

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Watch Sensory Overload now, streaming on Hulu. How long can a person stay in this sort of like interstitial zone, this gray, this little gray area, I guess? So ideally, under an hour. Okay. But, you know, depending on the surgery, sometimes we do have to go over an hour. And that's more of the extreme case. Like typically, it's 20 minutes or so. Do we know what effect it has on the brain to just

Be flatlining for an hour? So not well, not understood well. Incredible. What are you thinking at this point in the surgery? Like what's going through your mind? Just it's still so surreal. But, you know, that's a person and I want to do what I can to ensure that they're being taken care of as best as I can. I'm sorry. This is so, it feels...

Like something out of science fiction. That kind of melding of person and machine and you're turning people off and turning them on again. How's this job, how has it kind of changed the way, I guess, that you think about life and death? Yeah, it's definitely raised more questions than answers, you know? You know, you think about no brain activity, no heart activity. It's like, well, yeah, our brain

Patient is dead, but they still have blood flowing. So are they actually dead? But yeah, if we were to stop the machine, then they would for sure die. Right. Because that's their only means of support. It's pretty mind-boggling to think about still. Right. I'm trying to think about like this in-between state, that our definition is blurry enough to allow for sort of 20 minutes of silence.

Yeah. Feels, I don't know, I just, I think when I was reporting out the episode, I kept on being like, but surely we should just, surely we should know whether someone's, like, that feels like the most basic question is like, is this person alive or are they dead? Right. And like the doctor that you talked with in that redefining death episode said,

You know, you think of cardiopulmonary death, so you're not breathing and your heart's not beating. Or you think of brain death, you know, where the brain's unresponsive. And in these circulatory arrest cases, we have both of those. Right. But the patient isn't actually dead.

Somehow. How do you like, how do you reverse the process, I guess? Is it just like turning the temperature knob back up to bring the patients back to life? That's exactly it. But we have to do it very gradually because when you're at such a deep hypothermic level, if you warm the blood up too fast, what can happen is you can create...

microscopic bubbles. What? Like the bends? Yep. But from temperature? Yep. Just literally microscopic bubbles coming out of the water part of your blood. So you're doing it very slowly. How long does it take to kind of warm people up again? It depends on the size of the patient, but on average, probably...

Hour and a half or so. Wow, okay. As we warm closer and closer to normal body temperature, we're starting to get bursts of activity back from the brain. So basically the brain sort of like spits and spurts back into life, like an engine or something? Yep. Yep, they'll get just little bursts every so often. And then, yeah, eventually return to normal.

Honestly, any open-heart surgery is kind of a miracle, right? People like Adam and the surgeons he works with, they sort of have to get used to holding our lives in their hands. Yeah, it's still surreal. Just because this type of surgery especially is just one big nebulous area. I've been doing this over 12 years now, and it still just, you know, amazes me every day what we're able to do. In some ways, it's kind of like death itself. It's both...

Unbelievably complicated, mysterious, and hard to pin down. And also, it happens a lot to everyone in ways that are both miraculous and routine. You know, 50 years ago, when heart surgery was still in its infancy, you know, these were things that were just dreamt of. And now it's just like, oh, we got a circarest case today. It's the...

This conversation was a bit of an experiment.

Because one of my favorite parts of my day is checking our inbox to read all of your emails. People will tell us everything they think we got right in an episode or wrong in the case of the posture episode that I did. People send in questions that I'd never considered before. They will ask us to look into the geopolitics of things.

17th century metallurgy, for example. Or a listener wrote to us from a research vessel in Antarctica to tell us how their eye movements are being used to train a lander for a future mission to Europa. Another listener sent us proof of the comedy work that they did with Buzz Aldrin. And someone else sent pictures of whale sharks whose exposure to Cold War nuclear testing helped scientists figure out how old they are.

All to say, we are here for that kind of email. Like, we love your messages. And there have been a lot that we wish that we could share with you, our audience. This episode, where we called Adam back and talked to him about his job, this is how we've started. But we'd like to do more episodes like this to feature more listeners like Adam and maybe like you.

The best way for that to happen is for you to send us either an email or a voice memo. We love to read your messages. We especially love to hear your messages.

Just tell us your own weird, wonderful take on any of our episodes, how you are connected to the question we asked or the answers we didn't find, what you know that we have not yet figured out. Tell us new things to check out. Ask us new questions that we ought to explore.

Basically, just let us know what you're thinking. We are at unexplainable at vox.com. And please just reach out. In the meantime, if you want to hear more about how complicated our medical ideas of death are and how scientists are even trying to someday reverse it, check out our episode, Redefining Death.

This episode was produced by Meredith Hotnot, who also runs the show, and by me, Bird Pinkerton, who does not run the show. We had editing from Julia Longoria, with help from Jorge Just, sound design and mixing from Christian Ayala, music from Noam Hassenfeld, production support from Thomas Liu, and fact-checking from the wonderful Melissa Hirsch.

Thanks always, always, always to Brian Resnick for co-creating the show. And if you don't want to email us, but you do have thoughts, you can leave us a review or a rating wherever you listen. It really helps us to find new listeners. And it's really nice to read your thoughts on various episodes. You can also support the show and all of Vox's journalism by joining our membership program. You can go to vox.com slash members to sign up.

If you do sign up, you get ad-free podcasts, you get unlimited access to all of Vox's journalism, and you get the delightful sense of supporting a bunch of journalists who you hopefully enjoy. Right now, we are running a limited-time membership sale. So a membership is 30% off. So you can get that lovely sense of having supported journalism for 30% off. What a bargain.

Unexplainable is part of the Vox Media Podcast Network. And we will see you on Wednesday. Welcome to the premiere side of life. Corona Premiere.

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