Stuff You Should Know - How Therapeutic Hypothermia Works

Episode Date: May 5, 2015

Physicians noticed centuries ago that people exposed to cold temperatures often have amazing recoveries from serious medical emergencies. Now medicine is learning how to purposefully induce hypothermia in order to buy time to fix otherwise fatal trauma. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

attention bachelor nation. He's back. The host of some of America's most dramatic TV moments returns with the most dramatic podcast ever with Chris Harrison. During two decades in reality TV, Chris saw it all and now he's telling all. It's going to be difficult at times. It'll be funny. We'll push the envelope. We have a lot to talk about. Listen to the most dramatic podcast ever with Chris Harrison on the iHeart Radio app, Apple Podcasts, or wherever you get your podcasts. I'm Munga Chauticular and it turns out astrology is way more widespread than any of us want to believe. You can find it in Major League Baseball, international banks, K-pop groups, even the White House. But just when I thought I had a handle on this subject, something completely unbelievable

happened to me and my whole view on astrology changed. Whether you're a skeptic or a believer, give me a few minutes because I think your ideas are about to change too. Listen to Skyline Drive on the iHeart Radio app, Apple Podcasts, or wherever you get your podcasts. Welcome to Stuff You Should Know from HowStuffWorks.com. Hey and welcome to the podcast. I'm Josh Clark. There's Charles W. Eager Beaver, Chuckers Bryant, ready to get his therapeutic hypothermia on. Yeah baby, I'm chilling. Moving at a glacial pace today, right? I am. I'm sorry for that. That was actually a poke at the author of this article. Yeah, that stood out to me as well. I'm not done yet. Jerry's over there.

Yeah, we were goofing off about this article in HowStuffWorks that there were way too many cold puns for my liking. There was a lot of puns. You know, lot. Lots of them. This article stinks of puns. It reeks. So how are you doing man? How are you feeling? I'm good. Seems there's a sickness going around the office. Yeah, which I thought we knew here in 2015 that if you're sick you don't come into work. Right, especially when you have a liberal telecommute policy. Right. Like we do. I realize that people need to come in and shoot video and record and all that, but come in, you do that and you leave. That's right. And you wear like a plague doctor's mask the whole time you're here too. Yeah, I mean I have a biohazard suit

at my desk. Yeah, but it has a rip in it. Anyone can wear. It has a rip in it. It has a very small rental and cleaning fee. You're going to take a blood sample of mine wearing that thing. And it occurred to me as you were about to put it on like I don't know where that thing's been like that's a real biohazard suit and Chuck's going to use it to open my skin. Yeah, this sounds very odd. We don't just do this in the office. We did our blood types episode live here in Atlanta and we actually took Josh's blood type on stage because you didn't know it. No, when we recorded the version in the studio, I genuinely did not know it. Yeah, so I took your blood on stage. You trusted me. I did not wear the contaminated suit. No, you just used your dirty hands. That's

right. With no like rubber gloves or anything. And look at you. You're fine. And you know your blood type now. Yes, which was a positive. That's right. You're a positive guy. Yeah, pretty neat. So we should release that whole live show as a just a special. Yeah, little bonus. Yeah, a bonus. That was the word I was looking for. There's nothing special about it is just a bonus. Oh, it was special. Yeah, it's a good idea. Okay, look for that soon people. So today, Chuck, we're talking about therapeutic hypothermia. And I am very excited about this. This is my idea. This article. Yeah, it's pretty neat. I don't remember. I guess I first heard of it from that mosaic article that we both read to the big sleep. Yeah, awesome article. And if you

haven't figured out by now, we have started to on the podcast page for each episode, put related links on there on our site, stuff you should know.com. So that article's on there. There's a bunch of other stuff on there too that we'll cover. But be sure to check out that mosaic article. It's very neat. Agreed. And that article first introduced me to the concept of therapeutic hypothermia, or medically induced hypothermia is another another term for it. I don't prefer target targeted temperature management that sounds Yeah, corporate. Yeah, very corporate, you know, the HMO term for it, like we'll call it this because it'll less than the likelihood that we'll get sued or something. Exactly. Yes. I agree. But it's been around for a while. And the idea that

exposing people to lower temperatures to allow for better medical interventions, which is the whole basis of therapeutic hypothermia, yeah, has been around at least since the Napoleonic Wars. Yeah, it's pretty neat. I was interested to find that out. They noticed way back when in the 1800s, early 1800s, that troops and battlefield trauma wounded soldiers would the ones who were not kept to warm and cozy by the fire or in their tents, right? They're just left out on the battlefield in the cold. Yeah, they actually fared better. And they were like, wait a minute is and of course, they had no idea what was going on. No, they're like, did you notice that? Yes, I did notice that. They're hearty men. Well, back to our brandy. Yeah, pretty much. But they did

notice that the ones who were warm did a lot worse than the ones that were left out in the cold, which is super interesting. Yeah. But the real investigation into what was going on there didn't start until the 30s with a guy named Dr. Temple Fay. And he was actually the first guy to write about using therapeutic hypothermia, I think in 1945 was the first paper about it, but he was using it for a full decade or so before then, basically putting his patients in ice baths, opening the windows to their room during the winter, and just basically using any means he could to lower the temperature for I think he had, he was using it on traumatic brain injury patients. Yeah, and I'm sure he did a lot of explaining along the way to family members that were like, hey,

can you close the window and warm up my husband here? Right. And then he was like, all right, you want him to die? I think back then too, he was like, it's the 30s and this guy is a traumatic brain injury. Really, there's nothing I can do to make it worse. Yeah, that's true. His prospects worse. So why don't you just lighten up their family member. So there was another pioneer in the 50s named Dr. Peter Safar, SAFAR. And he actually began experimenting around with this in the ER as well, trying to reduce tissue injury and brain damage from a lack of blood flow. And this was mainly at the time in like stroke patients, cardiac arrest patients. And we'll talk more about it. There's all sorts of, well, not all sorts. There are several uses, like cases where

you would want to use this, and ranging from cardiac arrest to like a gunshot wound to I think what is the infant situation? It is called chock. It's a type of encephalophy. Where is chemic? Encephalophy? Yeah, we're a natal. Basically, the blood flow, the lack of blood flow to the brain is cut off for whatever reason, like maybe the umbilical cord gets wrapped around the baby's neck or what have you. It leads to a swelling in the brain. And they started using it to medical hypothermia to treat that. That's right. And that was in the 50s, right? Yeah, the 50s and 60s is when Dr. Safar was doing his work. So, this is all kind of going on on the side. And experiments into hypothermia had kind of a bad name thanks to

the Nazis and a little bit also the Japanese in World War II. But the Nazis, especially at Dachau, the concentration camp or the death camp there, experimented using unwilling human subjects. They experimented on the effects of hypothermia on people's bodies. They did all manner of horrible, grisly, gruesome stuff, of course, but they recorded the data. And there was a long debate over the years over whether that data could be ethically used. And on one hand, people were saying, no, it's the Nazis. They used unwilling subjects. It amounted to torture in the name of science. And I just used air quotes, right? And then other people said, well, wait a minute, these people died whether they wanted to or not. They were made to be these test subjects and they

gave their lives. We can honor them at least. By using the data that was called from it. Well, once they really dug into the data that the Nazis had accumulated, it was just like rank amateurs performing scientific experiments. They followed almost no protocol. They did terrible record keeping of descriptions of subjects and things like that. So it's almost like you just have to toss it out because you just can't trust it scientifically the data. Got to start over. But the idea that people were exposed forcibly to hypothermic conditions kind of gave hypothermia a bad name. So these guys experimenting with this stuff, it was French science for a while. Yeah. And then it started to come into the mainstream. And then everybody said, well,

wait a minute, hypothermia has all these bad side effects. Let's just table it for now. Yeah. And the 50s to NASA was doing a lot of work during the space race because the idea was, and this is really sort of two parts. There's the modern day cooling like that's not freezing somebody basically. And then we also have what's called suspended animation, which we'll get to later. Those are totally different things. Totally different things. But they follow the same process initially, right? Yeah. Well, sort of, I mean, the methods are different, but the same idea basically is to slow the body down. So down the heart rate, slow down everything. Your metabolism. Yeah. But NASA was doing this because they put a lot of money into it because

they thought two things. One, you could protect astronauts from a cosmic rays. And the other is basically straight up alien. Like we can freeze people on long journeys into space and then unfreeze them when they get there. Right. Which is not just alien. That's a bunch of sci-fi movies. No, it's Prometheus too. But there was a doctor named James Lovelock back in the day who was freezing hamsters until they froze. And then basically until he couldn't hear a heartbeat frozen. Yeah, they were clinically dead. Yeah. And then he would put a little hot teaspoon against their belly and warm them back up. Yeah. And he found that they were actually okay. And he was able to revive them. Some of them. Well, sure. Yeah. I'm sure there were losses along

those. But I mean, even one coming back to life and seeming normal again is pretty significant. That's a significant finding. Yeah. Because basically the idea was planted all of a sudden that hypothermia can kill you or it can preserve you and keep you from dying in an extreme situation. Right. Which is kind of counterintuitive. Like you think of people who undergo hypothermia. Yeah. Or, you know, being exposed to extremely cold temperatures. They're dead. I mean, we've all seen the shining. We know the end. Yeah. But apparently there's a rule of thumb among ER physicians and staff that there's no such thing as a cold dead body. Oh, I thought it was measured twice cut once. It's a little different. That's for the surgeons. Right. No, there's no such thing

as a cold dead body. Okay. You're only dead when you're warm and dead. Right. Because, well, there have been some cases throughout the years. The one that spectacular one. Yeah. This lady was she with Norwegian Anna Bagenholm. I don't even know what that is. It's not an umlaut. It's a single circle above that A. That's a very Norwegian. Yeah. Death metal band name. Oh, totally. So she was skiing and actually, I think she was Swedish, but she was on holiday skiing in Norway. Fell headfirst into a frozen stream and was trapped under ice, submerged for 80 minutes, stopped breathing, heart stopped drowned. Yeah. I mean, she was well known. She didn't drown. They thought she drowned until they reheated her 10 days. They reheated her and she was fine. Like,

weeks and months later, she fully recovered. Right. And basically, if you're underwater, warm water, you have a few minutes at most. But what they discovered was if you actually go into hypothermia, it can preserve your body, which was amazing and a big breakthrough into like, hey, maybe we can use this. Right. Yeah. And she was one of a few, a handful of people. And we'll talk about some others too. But what researchers into hypothermia have learned and why they figured out that you're not cold and dead, you're just warm and dead, is that it's not the addition of cold or the exposure to cold that kills you. It's warming back up in the wrong way too rapidly under the wrong circumstances. That's what can kill you. Yeah. It seems like it's a very

fine line between, we'll talk about the process, but you have to do it just right on the cooling side and the warming side if you want to be successful. Right. Exactly. They haven't quite figured it all out yet. This is in the very nascent stages still. It is ridiculously primitive. Yeah. And to the point where it's kind of like, if you're a doctor experimenting with this, you would be like, there's 100% chance that your dad is going to die under normal circumstances. We have this one radical technique we can try that might help. Can we try this? Yeah. And that whether the dad lives or dies after being given medical hypothermia, he's still going to end up as like the subject of a major paper that would be written because that's where it's at right now.

Yeah. And I read one doctor said that they think they pretty much know it's super possible and will work. He said, but it's the doing of it that's just really, really hard. Exactly. Yeah. I mean, like it makes complete sense intuitively. Yeah. We understand like what it's doing. It's just, yeah, the fine tuning, the nuance behind it that is still kind of a mystery. And the most brilliant doctor say, it's just really hard. He said it's really doggone hard to do. Yeah. It kind of makes you go, oh, yeah, you know, is that the quote? No, his quote was it's really doggone hard. And then my quote was, oh, that's good stuff. But we'll talk about medical hypothermia and what it is specifically in just a minute. Hey, guys, it's cheekies from cheekies and chill podcast. And

I want to tell you about a really exciting episode. We're going to be talking to Nancy Rodriguez from Netflix's love is blind season three. Looking back at your experience, were there any red flags that you think you missed? What I saw as a weakness of his, I wanted to embrace the way I thought of it was whatever love I have from you is extra for me. Like, I already love myself enough. Do I need you to validate me as a partner? Yes. Is it required for me to feel good about myself? No. Listen to cheekies and chill on the I heart radio app, Apple podcast, or wherever you get your podcasts. Attention, bachelor nation. He's back. The man who hosted some of America's most dramatic TV moments returns with a brand new tell all podcast,

the most dramatic podcast ever with Chris Harrison. It's going to be difficult at times. It'll be funny. We'll push the envelope. But I promise you this, we have a lot to talk about. For two decades, Chris Harrison saw it all. And now he's sharing the things he can't unsee. I'm looking forward to getting this off my shoulders and repairing this, moving forward, and letting everybody here for me. What does Chris Harrison have to say now? You're going to want to find out. I have not spoken publicly for two years about this. And I have a lot of thoughts. I think about this every day. Truly every day of my life, I think about this and what I want to say. Listen to the most dramatic podcast ever with Chris Harrison on the I heart radio app, Apple podcasts, or wherever

you get your podcasts. All right. So therapeutic hypothermia is basically when you lower the body temperature for various reasons to keep it alive. And right now what they're mainly doing, now, this isn't the second wave, which is freezing somebody. This is just cooling a body before and after surgery to help them increase their chances of survival, basically. Right. Your body typically... And they're doing that now. Yeah. On this side. Yeah. They're just not doing the other quite yet on humans. Right. Yes. So under normal circumstances, your body maintains a normal core body temperature, normative temperature, I think is what it's called, right? And that's somewhere between like 96 and 98.6 degrees. It's a normal human core body temperature. Yeah. And

all of this is... And dude, do you remember when I went on that crazy weird metaphysical tangent and does the body replace itself? Yeah. Somebody wrote in and said, check this article out. Here's a really great explanation of why things live, where life comes from. And it was this idea. It's a physics-based idea of life and evolution. And it says that because of entropy, because of one of the laws of thermodynamics, that atoms will arrange themselves in a way that they can take in energy and dissipate heat in a really efficient manner. And so, of course, atoms are eventually going to arrange themselves into life. It just makes total sense, right? So being living things like we are, we take in energy and we dissipate heat. And that's what forms our core body temperature,

right? Yeah. With therapeutic hypothermia, what you're doing is lowering the metabolic rate through the addition of cold. And so we put out less heat. And by doing that, we're also lowering our energy demand. So that little engine that's going all the time in our cells and our body in general gets slowed down. And it's not altered in any way except for the speed and the energy consumption. It's just slowed down. It's doing everything slower. And you can do that simply by lowering the temperature of the person. Yeah. And it's not just lower. It doesn't need to be faster. Does that make sense? Like the heart beats slower because it doesn't need to beat any faster. Right. So not like your body is struggling, your body is still doing fine. It's just reducing the

demand for stuff like blood flow and neurotransmitter action and stuff like that. Exactly. And ultimately, what your heart does is pumps blood. And what your blood has is, among other things, oxygen. And your cells need oxygen to carry out these metabolic processes to burn energy, right? Yeah. So if they need less, then your heart doesn't have to beat as much. It's like you said, it's just the normal processes, but on a much slower scale. Right. Pretty awesome stuff. It is. And it's just through the application of colder temperatures. Oh, yeah. And in this case, and we'll get to how to do it. But in this case, you're not, I mean, you're literally cooling the body with like ice packs and cold blankets and stuff like that, pre-surgery and post-surgery. Right. It's not

the suspended animation one that we'll get to when they're actually like pumping frozen saline through your veins. No, but there are some techniques for medically induced hypothermia that do put in like chilled saline to chill your body down very quickly. But it's not like replacing your blood. Yeah, yeah, yeah. I hear you. So there's a couple of applications at this point and the cases are either involve intervention or prevention. And intervention is when they're trying to prevent further damage from an incident like a stroke or cardiac arrest or sort of the two main ones. And then preventative wise, it's to extend operating time because back in the day, you could not operate on, well, back in the day, you couldn't stop the heart to operate on it.

No, which is, do you remember we did like this day in history about the first guy to ever do open heart surgery as a black surgeon in Chicago in like the early 20th century, I think? Yeah. And he did an emergency open heart surgery with a beating heart. Yeah. That guy was totally awesome. Yeah, champion. This was the case for a very long time and you couldn't stop the heart. They finally invented a machine that basically does the work of the heart and the lungs. Called the heart lung machine. Exactly. Where you're transferring blood through this machine. Yeah. And it's removing CO2, it's adding oxygen and it's pumping it back into the body while the heart and lungs are stopped. That's right. Revolutionized open heart surgery.

There's problems with it. One of the problems is when the blood comes back in the body, since it's been through this machine, it may have picked up some sort of foreign in bacteria and the immune system sometimes mounts an attack on the blood. So this, this machine poses its own problems and alternatively, an alternative method for stopping the heart or slowing the heart is to use medically induced hypothermia. So that's an intervention, no, a prevention, preventative use of medically induced hypothermia. Yeah. But intervention is another way, like you said, and it can have to do a stroke or heart attacks. Or cardiac arrest.

Right. Aren't those two different things? I think so. Yeah. Technically. Okay. But it's some sort of cessation of the heart pumping blood. And the big problem with that, it doesn't really matter whether your hand is getting blood for a while. The big problem that comes from a heart attack is your brain not getting blood for a while. Right. So here's what happens when blood stops flowing into your brain, right? Yes. And we covered this somehow in the how dying works episode. Yeah. The dying process. Okay. Because it's not a, it's not a black and white thing. You're not alive and then you're dead.

Right. It comes in many, many stages. Right. And we talked about the stages of death. Yeah. So there's, when, what they've discovered is that, yeah, you're not like, I'm alive and now I'm dead is what we covered in the how dying works episode. Right. Yeah. Like dying in your sleep. I mentioned that the other day. Yeah. How like, nobody dies in their sleep. That's just a nice thing. That's a nice way to say they died in their bed. Yes. Overnight. Overnight. Yeah. Exactly.

So yeah, there's, with medically induced hypothermia, they've been able to extend that, that time between when you appear to be dead and when you're actually dead. Right. And by extending that time, they, they can intervene better. Yeah. And it buys them time. Yeah. Even a little bit of time can go a long way. So one of the, one of the things that medically induced hypothermia has been shown to really help is what's called return of spontaneous circulation after you have a heart attack. The problem is, is your heart and lungs can, your cardiopulmonary system can start working again. Yeah.

But you might not regain consciousness. And in that case, that's a sign that your brain may be in trouble. Your cognitive function, you may be suffering brain damage at that moment. Yeah. And isn't the stat one in 10 cardiac arrest outside of a hospital has it like goes on to live like a, without brain damage. Yeah. 10, only 10%. Right. Because you have a very small window. Right. And that window is usually longer than it takes to get to the hospital. Right. So if they bring you in and you are showing signs of ROSC without return to consciousness too,

they may induce medical, medical hypothermia. And the reason why is the heart pumps blood. Yeah. And blood contains things, including oxygen, right? Sure. And one of the organs that uses probably the most oxygen of all is the brain. And the brain uses the oxygen to burn energy basically. It uses it to oxidize glucose. And when it does that, the reason it does that is because your neurons, your little neural cells, that fire, the way they fire is because they're a chemical battery. They're a chemical battery with a stored potential

charge. And they do that by keeping a lower concentration of electrolytes inside the cell than outside. Right. So this difference creates the electrical charge that your neurons use to fire, right? Right. On normal circumstances, that's all well and good. But when they stop, when they stop getting oxygen, they can switch to anaerobic mode for a little while. So they're still burning energy, but they're like, you need to start breathing again because this is not very efficient. Yeah, it's like when the emergency lights go on.

Exactly. Yeah. Exactly. So as a byproduct of anaerobic respiration, you get the stuff called lactic acid. Yeah. Lactic acid in and of itself isn't bad, but it can build up. One of the other things that happens too when this, when that runs out is the difference between electrolytes inside and outside the cell stops. Right. Like it evens out.

Yeah. And now all of a sudden you have things like calcium, potassium, sodium coming in and out of the cell as much as they please. And the cell is like, what is going on? This isn't good and releases its store of glutamate. Right. And glutamate is a neurotransmitter that excites neurons. And again, in very small amounts, totally fine. It's needed. But when a neuron just freaks out and dumps all that into a synapse, it sets off that neuron and all these other neurons and makes them go totally crazy. And it also lowers their structural integrity. So all of a sudden you have neurons going nuts, dumping their contents everywhere,

and then creating also free radicals, which are atoms with unpaired electrons. And they run up against the cellular structure and the cell walls and start borrowing electrons from those atoms. And that weakens the structure even more. So even more stuff gets dumped out into the intercellular matrix. And you have a problem. This is a really big problem in and of itself. Right. You still with me? I'm still with you. Okay. That's what happens when you stop getting blood flow. It's just as bad if not worse when you start getting blood flow again, because you have all these damaged cells, you have dead cells, and when you have dead cells that have dumped their contents, one of the roles that your white blood

cells, your immune system plays, is to come clean up dead cells because that's toxic stuff. That's bad stuff and you need to get it out of your body. So when blood flow returns again, all of those white blood cells come to the site of this problem, your brain, and they start cleaning up. But when they do, an inflammatory reaction happens and all of a sudden you have swelling in your brain and the process gets even worse. So these structurally challenged neurons don't just erupt immediately. They do immediately, but it can continue for hours and days afterwards. And all of this happens from a heart attack. But by applying cold temperatures and bringing hypothermia on somebody, you can actually stop this process. You can stop the glutamate from

ever being dumped they're finding. Right. And so give time basically for your brain to rebuild itself in the way it needs to by lowering that metabolic rate that your neurons need. That's what it does for a heart attack. Cardiac arrest. There are definitely two different things that looked it up. Okay. And someone's going to say, you guys should do a podcast on that because you don't know what you're talking about. Right. It's coming. So probably after that, we should take a little break, huh? I think so. You want to get some tea? Yeah. And we'll be back with more cool stuff. Hey guys, it's Chiquis from Chiquis and Chill Podcast. And I want to tell you about a really

exciting episode. We're going to be talking to Nancy Rodriguez from Netflix's Love is Blind Season 3. Looking back at your experience, were there any red flags that you think you missed? What I saw as a weakness of his, I wanted to embrace. The way I thought of it was whatever love I have from you is extra for me. Like I already love myself enough. Do I need you to validate me as a partner? Yes. Is it required for me to feel good about myself? No. Listen to Chiquis and Chill on the iHeartRadio App, Apple Podcast or wherever you get your podcasts. Attention Bachelor Nation. He's back. The man who hosted some of America's most dramatic TV moments returns with a brand new Tell All podcast. The most dramatic podcast ever with

Chris Harrison. It's going to be difficult at times. It'll be funny. We'll push the envelope. But I promise you this, we have a lot to talk about. For two decades, Chris Harrison saw it all. And now he's sharing the things he can't unsee. I'm looking forward to getting this off my shoulders and repairing this, moving forward and letting everybody hear from me. What does Chris Harrison have to say now? You're going to want to find out. I have not spoken publicly for two years about this and I have a lot of thoughts. I think about this every day. Truly every day of my life, I think about this and what I want to say. Listen to the most dramatic podcast ever with Chris Harrison on the IHeartRadio App, Apple Podcasts or wherever you get your podcasts.

All right. So how has this magic done? It's pretty easy actually. It's easy in theory. But there are generally three stages for therapeutic hypothermia and they are induction, maintenance and rewarming. And they are all very carefully monitored and have to be done just right. So when they go to cool the patient, first thing you'll do is sedate them because shivering is the body's way of trying to stay warm. Your body wants to be warm and is going to do everything it can until you die like Jack Nicholson outside the maze and the shining to stay warm. Yeah. And you can't have a body shivering because number one, it fights off that hypothermia you're inducing, right? Yeah. Number two, that uses a lot of energy, which is what you're combating right

there. You're trying to slow the metabolic rate, not increase it. Right. And you want a patient that's still as well. Right. Like one of the problems I've seen is the problem with doctors like performing in these conditions because like stopped squirming. Well, that too. And they have to keep the room very cold. It's not like they're in like an 80 degree room and they're trying to keep them like everything is cold. So the doctors have to perform under those circumstances too. So they may shiver themselves, but to keep the patient from shivering, they just solve that problem by injecting them with the paralytic. Exactly. So now they're nice and still, they're cooling down. The cheap way to do it, which is, and they're not doing it because it's cheap,

but ice packs basically armpits, groin, chest, they're basically wrapping your legs up and everything they can with ice packs. And that's just going to cool you down pretty quickly. Like you said, they will sometimes use like catheters or a chilled saline solution. Right. Those are more invasive and more dangerous, obviously. They also work a lot quicker. Yes, very much. And I think they want to cool people down pretty quickly too, which is, I don't think they want to do the cooling part slow. No. And that's a really good point. I'm glad you brought that up, especially if you're bringing a patient's body down to a really low temperature. Yeah. You have to protect against ice crystals

forming in the cells because that can rupture cells. And that's a whole set of other problems, right? Yeah. So if you bring the temperature down very quickly, you can prevent ice crystals from forming. That's right. Because they require time to form. Yeah. So if it's super fast, they won't, they won't form. That's the impression I have. Okay. So during the maintenance phase, it's exactly how it sounds. They're just maintaining that temperature, keeping a very close eye. Again, using these cold water packs or forced air blankets and things like that. Which sound kind of cool. They sound kind of cool. The forced cold air blankets. Yeah. They'd be nice for these Atlanta summers. Get ahold of one of those.

And there are a lot of risks along the way. Erythmi is a very big risk. And electrolytes leaving like potassium, which is necessary for the heart muscle to function as it should. So they're pumping the electrolytes back into you because you're losing them. Right. So again, they're just maintaining everything. And then the rewarming part has to be done very, very slow. Otherwise, very bad things can happen. And we're talking 0.27 to 0.9 degrees per hour. Fahrenheit. 0.15 to 0.5 degrees Celsius per hour. Yeah. That's a very slow rewarming process. That's right. But if you got a good forced air blanket, you can really control the warming. Yeah. Get a good brand, not some off brand.

And again, they're not like, oh, well, if we, if we heat the person back up at 0.15 degrees Celsius per hour, then this is what's going to happen on a cellular level. Like they're not quite there yet. They just know that that's the sweet spot for rewarming somebody. That's right. So Chuck, one of the really problematic side effects with rewarming a person is odor. Yeah. Yeah. They're like, wow, you started to get gamey while you were under. Sure. Is blood clots. Oh, yeah. So when your, when your blood stops pumping because your metabolic rate is so low, the blood inside you starts to form clots thanks to your red blood cells and your platelets. And when you warm back up, all of a sudden you have clots all over your body. And

that's a real problem. That alone can kill you. And that's part of the problem with the rewarming process. Yeah. But it turns out that investigation into animals that hibernate, they found that animals have some sort of technique to where their red blood cells just kind of disappear. And then once the animal comes out of hibernation, it reappears. Yeah. They don't even know where they go. No, but they do know that they, they don't get rid of them somehow and then regenerate some other ones because their reappearance is so fast that they just think the body somehow absorbs them and then releases them again. Yeah. And the other really cool thing, and we're kind of into hibernation right now, which we'll talk about in more detail, but white blood cells,

hibernators remove white blood cells from their blood and storm in the lymph nodes. Yeah. And then about an hour and a half after these animals awake, they reappear. And this has a couple of functions. One is when you're an animal undergoing hibernation, your immune system is going to be compromised because those white cells are in storage. Right. That's a problem. Yeah. It's a problem, but just knowing that animals can do these neat little tricks with their platelets and white blood cells could have like a big effects on us if we can figure that out for ourselves. Well, yeah, specifically also Chuck, because remember when we were talking about your neurons dying? Yeah. And when you reperfuse, when you bring blood back to the brain again,

one of the things that brings with it is those white blood cells, and they start going on the attack. Yeah. So if you can figure out how to take white blood cells out of the equation, it's going to reduce things like post warming swelling, which can give you brain damage itself. Yeah. And you talked about the heart lung machine. One of the big dangers with that machine is aseptic sepsis. And if you have those white blood cells stripped away, then you're not going to be at risk for that. Right. And they'll be able to hang on to blood longer. Right now blood donations can only be kept a week. It goes rank quick. Yeah. And transplant organs can be basically cryo protected for longer too, which is pretty neat.

Yeah. So I guess we should talk about hibernation for a minute because it's one of the neatest things in nature, I think. In torpor, basically torpor are short periods of hibernation, reduced body temperature and inactivity. And when you link a bunch of torpor's together, that's full on hibernation. So yeah. It's also like a hibernation light too. Yeah. You know what I mean? Like you can be, I think a bear enters torpor where it's, it wakes up like every once in a while and eats or poops or does something. And then there's some animals where you can just shake them like this and they will not wake up and they're in full on hibernation. Yeah. And the animals have to prepare for this. They just don't go beddy by

and stay asleep for a long time. Right. First they become diabetics basically by gorging on food and becoming obese. Sounds familiar. And, but it doesn't affect like humans does. It doesn't make them unhealthy. Like their body knows it's reparation for hibernation. Knows what to do with it. Exactly. Plus they're probably also eating unprocessed foods too, which I think makes a difference. Yeah. I think so. They don't atrophy like humans do. Like when we lay around in bed, we don't, our muscles will atrophy. Animals can go months and months without moving. Spectacular. Spectacular. It also kind of suggests that humans aren't supposed to hibernate. Yeah. Well, although, you know, when they found some of these frozen people,

oh yeah, they start to think maybe human hibernation is such a bad thing. Their lungs when you hibernate become covered at the really thick like mucusy deposits. It basically looks like a human with asthma, but it's, you know, a protective measure again. They go in their brains kind of go into a stage that looks like early Alzheimer's. Uh-huh. Again, not a bad thing. It's just preparation. And it, it's weird. I mean, it looks like animals are almost dying when they're preparing for hibernation. Well, yeah. In some cases. And sometimes they do, especially when they're forced to come out of hibernation and then go back in, their energy stores aren't, aren't built for

that kind of thing. Like so they probably will die because they'll start a death because it required so much energy to wake back up again. Or they're also vulnerable to predators too. Oh yeah. Good point. Which makes you wonder like, what's the point of hibernation? And the point is, well, it's they, they don't have enough energy to go elsewhere when temperatures get cold. So they just kind of shut down their metabolic demand when food becomes scarce. Yeah. And for the longest time, we didn't think that any primates could hibernate until 2004 when they found a lemur from Madagascar. Oh yeah. That could hibernate. And well, at least go into the regular torpor. Right. Hibernation light.

Still. And they said, we share about 98% of our genes with the lemur. And they said. It's basically like our cousin. Yeah. I mean, the doctor basically said it would be really remarkable if the ability to hibernate light within that 2% that we don't have. So basically, humans may have more of an ability to do this than we think. It would just have to be medically induced. Well, you know, who demonstrates that very well, Chuck? Who's that? A man named Mitsutake Uchikoshi. Oh yeah. We talked about him. What did we talk about him? And was it cryogenics episode? It was a long time ago. I just remember that one. Yeah. Cryogenics. Hi, frozen body. That's a good one. That was a good title. But yeah, I remember this guy though, for sure.

So he is a Japanese man who at age 35 was hiking with some friends in Japan. And he decided to turn back by himself to go, I don't know, get something out of his car. And he wandered off. And apparently in a meadow, tripped over a rock and fell and hit his head on another rock and lay there exposed to these cold temperatures on this mountain for 24 days. And he was found basically in a state of hibernation. His body temperature was through the floor. And he had almost no pulse. His temperature was 71 degrees, which is 22 degrees Celsius. That's his body temperature. That's pretty, that's like a hypothermic state. And he was in this weird kind of state of suspended animation for 24 days. He went without food, water, nothing, just laying there,

living in some weird way until he was rescued and returned to complete normalcy. Yeah, it's like the lady, the skier who was frozen, not nearly for as long, but these cases where humans' bodies are defying what we thought they could do can give us insight into like, hey, how do we manipulate this for good? How do we use this to get to the stars? All right, so I mentioned earlier that NASA was kind of leading the charge for this really cool suspended animation where you're basically freezing a person like Han Solo in carbonite. Yeah, except it's not carbonite. It's not exactly like that. But it's sort of like that. Okay. Actually, it's not like that at all. All right. And where NASA dropped off, the U.S. Army picked back up with some funding. Oh yeah,

this guy. Because they basically said on the trauma hospitals during wartime are chaos because you're trying to save a person, you're trying to treat their immediate wound, you're trying to stabilize them, you're trying to make them better, you're trying to prevent blood loss. It's not an easy thing to do. It's not like MASH, you know, where they just make it look super simple. Right, while everybody's drunk on homemade gin. Yeah, so they're thinking, I wonder what that stuff tasted like. I always wondered, but they're still... They seem to like it pretty much, pretty well. Well, it's because they didn't have it. I know, but they really seem to enjoy it. Well, the way they handled it was very much like a fine martini. Yeah. But you know, it was just like swill.

I don't know, they were at it for several years. Yeah, that's true. We'll have to ask Alan Alda. Oh man, I'd love to meet that guy. Oh yeah? One of my heroes, sure. Attention, Alan Alda. Reach out to us so Chuck can meet you. That would be great. My brother met him. I'm sure he did. He worked on a movie with him. He probably gets Christmas cards from him still. No, but he did get a picture with him, which is pretty neat. That's nice. So where was I? Oh yeah, MASH operating rooms. Yeah, because if you're a doctor, even in a battlefield hospital, you're like, I want a coffee break too. And so to be like, I don't have time for this guy right now,

freeze him to have that ability. That would be magnificent. Or if you did have time for the guy, but you literally didn't have time to fix these horrific wounds that he came in with, you could also say, freeze him to buy me some time. That's right. And that will give you the time to basically operate on this guy and completely repair heart or his brain or what have you. That's right. And that's what medically induced hypothermia does. It buys you time for either the body to heal itself in ways we don't understand, or for you, the surgeon, to sew somebody up who without hypothermia would just be a lost cause. Yeah. There's a doctor named Sam Tisherman from the University of Maryland. Go Terps.

Working with the University of Pittsburgh. What are they? Panthers? University of Pittsburgh. Pitt Panthers? I think so. That sounds right. It does. We'll go with Panthers. Panthers. If I got that right, I'm so sorry. Pittsburgh. We love you. But he is working hard to basically put patients into severe hypothermia or suspended animation. They're calling this emergency preservation and resuscitation. And this is the one that they haven't yet experimented on humans. They think they're pretty close, but this is the one where they flush the body with freezing cold saline solution. Right. Which prevents ice from forming.

Yeah. And it's worked on dogs. Yeah. And I think... Works on dogs. Gotta work on humans, too. Well, they did some experiments on pigs, too, because one of the things they think they can do where it's not like if you've had a cardiac arrest or a stroke, but again, with trauma, like a gunshot, you just can't... And I never knew this. You can't resuscitate a person with CPR that's had blood loss due to trauma. It's completely different than cardiac arrest. Why? Because the closed circulatory system has been opened? I have no idea. I bet that's it. Because of the drop in blood pressure, it's just not working.

It's like sucking through a straw that has a hole beneath your lips. Like a lot of it's escaping. A lot of the air is escaping, so you can't get as much draw. Yeah. I guess that makes sense. I'll bet that's what it is. All right. Well, we'll probably find out. But with trauma like a gunshot wound or something or a stab wound where you lost so much blood, you're dying. This is when they're using these super, super cold temperatures. It's a tube inserted into the aorta, literally.

Right. And they've done this on pigs. In 2006, they examined deep, profound and ultra profound freezing of pigs who had uncontrolled bleeding wounds. And I imagine that they... Where'd they get those? Yeah. Imagine they induced those as well. Go stab that pig, you grad student. Yeah. There's one creep.

Postdoc. To get to do, you know, all the stabbings. That's why I'm here. I'll get Ronnie. And they found that the ones who went underwent the most profound hypothermia had the highest survival rates. Like those French soldiers let down the battle zone. Yeah. Exactly.

And then in 2000, they did the same thing with dogs, except that they weren't stabbed. It was dogs and cardiac arrest. They may have induced that too, though. Can you think of it? They'd be like, do you want this bone? No, you can't have it. But they used ice cold ceiling in that case, and their chances of survival with no brain damage really increased.

So it's, you know, there are risks, though. It's not the easiest thing to do, like we said. And I know pneumonia was one of the risks for years, even with just the regular cooling, right? Yeah. Pneumonia slowed heart rate. Apparently, you can enter hyperthermia while you're being re-warmed. Like you get way too hot. Your body temperature increases too dramatically.

There's a lot of problems that blood clotting is still an issue and probably will be for a while. Yeah. With Tisherman's case, trying to use humans, though, there's a couple of problems. One is they have to get consent from a person to undergo an experiment like this. Right. But you can't give consent when you're wheeled in there. Right. Unconscious from a cardiac arrest. So what he's trying to do is just spread the word, literally just spread the word to the

citizens in his area, that there's this thing. And if your husband or wife has a cardiac arrest, ask for the cold treatment. Right. Where we completely pump their blood out and replace it with frozen saline, freezing cold saline. It's pretty amazing. It is. And, you know, there's a lot of people who are still very skeptical of the idea that medically induced hypothermia can actually work. But there's also a growing body of studies that show that it does that has a significant impact.

Like there were a couple, there were several in 2002 that really broke the thing open. Yeah. Where it was like, these people have a 25% chance of recovery without it. They have a 50 or 75% chance of recovery with it. Right. And that's really tough to ignore. Yeah. It's amazing. Amazing stuff.

Into the future, Chuck. Let's go. If you want to know more about medically induced hypothermia, check out our podcast page for this episode. It's got a bunch of cool links and you can type therapeutic hypothermia in the search bar, howstuffworks.com and it will bring up this article. Full of puns. And since I said search bar, it's time for listener mail. I'm going to call this Josh's theory on satire. Remember that? We talked about that in the very recent show.

Clown. Clowning. Do you want to summarize your position real quick? That maybe satire is just a release and does it affect change? Is that the nuts and bolts of it? Yeah. Basically, it lets the populace who's angry let off steam at the leadership without actually forcing the leadership to change. All right. So that brings us up to speed. And this is from Chelsea. She said, I just started listening under a year ago when a change in jobs landed me with a 25 minute walk to and from work every day. I think she's in Dublin. She says, I find myself laughing

out loud at your repartee and my boyfriend is affectionately started referring to you as my nerd friends. But he's a listener now too. It sounds like Dublin. I'm actually writing in regard to Josh's theory on satire. It's a really interesting point, an angle I had not considered myself. I think there's another way to look at it, which is that satire has the ability to plant the seed of descent in a non-threatening way. And thus can eventually be a force of change. For example, someone may not be aware of a particular foible of a leader. The satirist points it out in a funny way. Now that someone

has an awareness without feeling preached at and has it in their mind the next time the leader does something untoward. Or perhaps they were aware of said foible, but the satirist opened their eyes to just how ridiculous and or dangerous it is. So while there's certainly a possibility satire can act as placation or a way of letting off steam, there's also a very real possibility that can spark, be the spark that ignites an eventual change. It is a good point. Yeah, and that's from Chelsea and Morgan Hoffman. Thanks a lot, Chelsea and Morgan Hoffman of Dublin, Ireland probably.

Uh, well, she just said Dublin, not Dublin, Georgia. I'm going to go ahead and assume Ireland. Yeah, and boyfriend. Yes, thank you both for listening. We appreciate it. And if you have a counterpoint or your own theory or hypothesis or just want to say hi or whatever, you can tweet to us at syskpodcast. You can join us on facebook.com slash stuff you should know. Uh, you can send us an email to stuffpodcast at howstuffworks.com. And as always, join us at our luxurious home on the web, stuffyoushouldknow.com.

For more on this and thousands of other topics, visit howstuffworks.com. We have a lot to talk about. Listen to the most dramatic podcast ever with Chris Harrison on the iHeart radio app, Apple Podcasts, or wherever you get your podcasts. I'm Munga Chauticular and it turns out astrology is way more widespread than any of us want to believe. You can find it in Major League Baseball, international banks, K-pop groups, even the White House. But just when I thought I had a handle on this subject, something completely unbelievable happened to me and my whole view on astrology changed. Whether you're a skeptic

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