Science Friday - Anesthesia 101, Carbon-Sequestering Poplars, Period Book. April 21, 2023, Part 1

Episode Date: April 21, 2023

An Explosive End For A Massive Rocket This week, SpaceX attempted the first uncrewed orbital test flight of its massive Super Heavy rocket topped with an experimental crew capsule known as Starship. After one aborted launch earlier in the week, the huge rocket successfully lifted off Thursday morning—but minutes later, the Starship component failed to separate from the Super Heavy booster, and the combined rocket stack exploded. While a setback for the team, SpaceX head Elon Musk said that a lot had been learned from the flight, and another test launch would take place in several months. Purbita Saha, senior editor at Popular Science, joins SciFri’s John Dankosky to talk about the launch and other stories from the week in science, including an Earth Day look at water conservation issues across the country and the materials science of Maya plaster. Plus, you can now listen to Science Friday's new arts podcast, Universe of Art. SciFri producer and Universe of Art host D Peterschmidt joins John to give a sneak peak of some of the episodes.    Dismantling Myths About Menstruation Saying the phrase “menstrual blood” or or the word “period” can feel almost dirty. That’s because in the western world, people with periods are taught not to discuss this exceedingly normal biological process. Half the world will menstruate at some point in their lives, and yet menstruation remains exceedingly under-studied. Biological anthropologist Kate Clancy dug into the history of menstruation research, and the myriad misconceptions about it, while working on her book “Period: The Real Story of Menstruation.” What she found was a lack of basic understanding of the biological process, from physicians and menstruators alike. Clancy speaks with guest host Maddie Sofia about the misconceptions of a “normal” menstrual cycle, and other persisting period myths. Fighting Climate Change With Genetically Modified Trees Vince Stanley has a saying, which he holds as true in a commercial forest as on a row crop farm: Every acre has a plan. In a wetland he owns in Tattnall County, about 70 miles west of Savannah, downhill from an orderly grove of predictably profitable loblolly pines, he is trying out something new. “Now, look at this guy right here,” Stanley said, pointing out what looked more like a stick in the mud compared to the tupelos growing a few yards away in the deeper water. This stick, surrounded by pin flags and planted about six feet away from its sister, had signs of new life: dark green leaves. “That’s impressive,” Stanley said. And the germ of the new plan for these acres, is something that, until now, Stanley said he didn’t really have. “We’re just leaving this up to Mother Nature,” he said. “So now with Living Carbon, we’ve gone to Option B.” This nascent tree and 10,499 others are at the heart of Option B, what might be the first effort of its kind in the nation: genetically engineered trees planted in a forest. What’s more, these trees are for sale. Read the rest at sciencefriday.com.   All You Need To Know About Anesthesia If you’ve ever had surgery, you’ve probably wondered about how anesthesia works, or maybe even lied awake at night anxious about going under. If you’ve ever been there, I’m sure you remember: Right before surgery, you get rolled into the operating room. The anesthesiologist tells you to start counting down from 10. The next thing you know, you’re awake in the recovery room and you don’t remember anything that just happened to you. How exactly did anesthesiologists manage to get you safely into that state and back out again? Guest host John Dankosky talks with Dr. Louise Sun, professor of anesthesiology, perioperative and pain medicine at Stanford University Health and Dr. Gunisha Kaur, anesthesiologist, director of the Human Rights Impact Lab, and medical director of Weill Cornell Center for Human Rights at Weill Cornell Medicine about the basics of how anesthesia works. Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

This is Science Friday. I'm John Benkoski. And I'm Maddie Safaya. You may know me as a former host of the show Shortwave from NPR. John and I are sitting in this week for Irifledo. Later in the hour, debunking myths about periods. Plus, you ever wonder how anesthesia works? Well, we'll give you a crash course on how anesthesiologists are able to create that perfect combination of drugs so you're asleep, you don't feel pain, and you don't remember the surgery. But first, this week, SpaceX attempted an uncrewed test launch of its massive super heavy rocket, topped with an experimental space vehicle that's called Starship. The huge rocket did launch, but minutes later it exploded. Joining me now to talk about that and other stories from the week in science is Perbita Saha. Senior deputy editor at Popular Science, based in New York City. Per Bita, welcome back to Science Friday. Yeah, hello.

So let's start with this rocket. What exactly was this big rocket and why was this test so significant? Yeah, this flight test was really the hype of the week. It was originally scheduled for Tuesday, but then was moved to Thursday morning. And it was the first time that the starship was going to be launched with the super heavy rocket booster. So this contraption is massive. It's almost 400 feet tall, weighs a couple million pounds. and there are 33 methane engines on that thing.

So getting it off the ground was a real feat in itself. Yeah, and I suppose we should be using the past tense here because it exploded as we saw. Do we know what went wrong? Well, the goal was to get the rocket into orbit, even though SpaceX said there was less than a 50% chance of that happening. So four minutes into the flight, over the Gulf of Mexico, I think the rocket was only 25 miles up

in the atmosphere, it just started spinning and then it exploded. And it probably won't be the last one. Paring these two together is really essential for, you know, using the starship for the Artemis 3 moon landing mission, which is the plan in 2025. But to get there and to actually carry cargo and carry astronauts, SpaceX is going to have to test this thing many, many more times. And their strategy seems to just be launch it and see how far it goes. Well, let's stay in space for just a moment here. Monday is the anniversary of the launch of the Hubble Space Telescope. And you've got an article coming out about just why it's still so relevant, even with the

amazing new things that we can now see with the JWST telescope. Tell us about what's so important about this Hubble history. Yeah, with all the JWST amazing images that we've been seeing, a lot of that, that have focused on galaxies and nebula that Hubble previously saw through its lenses. And this just had me thinking, what is Hubble still doing? And is it still relevant to astronomy today? So I talked to two experts, Ray Villard from the Space Telescope Science Institute, and Jennifer Wiseman, a senior project scientist from NASA recently. And both of them agreed that the two really complement each other well.

Hubble is the OG, you know, it went up in space 33 years ago. And when it did, it was looking at parts of the infrared light spectrum and UV light spectrum that no other space telescope could see. So a lot of the star formations and other parts of the solar system that we've seen through Hubble's eyes, those were unprecedented at the time. JWST builds on that because it can see parts, of star formations that are actually relics from an ancient time because it can see further into the infrared light spectrum. So it has a different capacity than Hubble. And when they both have their lenses fixed on a particular subject, it gives us the entire life history of that group of stars, let's say. Well, speaking of life history, though, how much longer does Hubble have to

live? HUBL is in pretty good shape. I mean, it can go at least another decade, both of these experts say, but maybe even longer. It might surprise us. It is sagging a little bit in its orbit, so there might be a plan to boost it up a little, maybe with SpaceX's help. But Hubble is still kicking. There are hundreds of scientific proposals to use it each year. I really love this quote that Ray gave me. He said that there's only one Hubble. And if you're comparing them to music icons. Hubbell is like the Beatles. There were only one Beatles. He did concede that maybe JWST is like the Rolling Stones. I suppose that's a good analogy. Well, this weekend is Earth Day, and it means we're thinking a lot about the environment, of course. We've talked a lot about

water conservation issues on the program, especially what's happening around the Colorado River Basin. You've got some water conservation news that's coming not out of the west, though, but coming from Washington. What can you tell us? Yeah, so we have this years-long battle over the Clean Water Act and a very tiny portion of it that can have a really big impact on local habitats. A couple years ago, the Obama administration expanded what's called the Waters of the U.S. rule, which actually defines which kind of water bodies are protected by the Clean Water Act. And they expanded it to include not just rivers and lakes and big bodies of water, but also tiny pockets like wetlands and streams. And during the Trump administration, this definition was limited again.

So there's been this back and forth, and now that case has finally gone up to the Supreme Court. They just heard the arguments last fall and are expected to decide on what the final definition should be. Should it include all wetlands? Should it only include wetlands that are permanent or next to running bodies of water? So this decision is expected later this year, probably late summer in the fall again. And it's a lot of legal gnarliness, so it's hard to think of how that impacts us as individuals every day, right? But if you think about it, wetlands are one of the most ubiquitous landscapes across the U.S. pretty much everyone has a wetland in their neighborhood. And even if we don't drink straight from them, they are very important to our local health.

They help protect us from storms. They are gold mines of biodiversity. So having the Clean Water Act protect wetlands, that makes a pretty big difference. And I've just been thinking about that in terms of the Earth Day message because we have struggled for so long to preserve water and to make sure that it can be shared equitably. And it's something we can continue to do in our individual lives, but also press our governments to prioritize. And also just understand how it can work better around the world to get water to the people and to the living things that need it most. Yeah, I think it's a really great message as we head into this Earth Day.

weekend. I want to go to our last story, Prabita, and it's really cool. It's material science, but it's not exactly a new story. It's about how the Mayans made their plaster. What can you tell us about this? Yeah, so this finding is quite fresh. A mineralogist from the University of Granada went to the ancient Maya city of Copan, which is in present-day Honduras, and he took a look at some of the structures that have persevered over a millennia there. And the reason that they were so resilient, possibly, is because of the plaster that they were built with. It wasn't any old plaster, which is usually made of limestone, water, and some chemical reactions. But rather, the ancient Maya masons probably mixed in plant sap from two tree species in their local forests.

The power of the plant sap was that it made the structures more resilient. to water and the humidity in the local environment. The mineralogist recreated this special mixture and then compared it microscopically to another naturally made substance known as Mother of Pearl, which is seen in the shells of mollusks. And on a microscopic level, they had a very similar structure. There was kind of like a crystalline hard structure

and then some flexible proteins in between. So basically how mollusks withstand weathering under the ocean waves, that's kind of how these Maya buildings withstood the natural elements, which is really neat. I mean, we're all still guessing here, but it's a pretty cool experiment. It's a very cool experiment. I love the connection between these trees and these traditional building materials and mollusks and all coming together. And we can actually learn something about how people built something.

all those years ago. Perbita, thanks so much for bringing us that story. It's so cool. Pramita Saha is Senior Deputy Editor at Popular Science, based in New York City. Thanks for being here. Thank you. Have a lovely weekend. You as well. And now for some other news, we want to tell you about a new podcast from Science Friday that we think you're going to love, especially if you're a fan of our arts stories. It's called Universe of Art. And I'm here with its host, Science Friday producer, D. Peter Schmidt. Hey, Dee. Hey, John. So tell me about this podcast. Yeah, so some of my favorite Science Friday stories are the ones where art intersects with science in some way.

I'm a musician, so I'm a little biased here. But we wanted to make a podcast just for those stories, and we're really interested in focusing on artists who use science to kind of level up their creations. And also scientists who use art to, like, reinterpret their discoveries in a new medium. And the whole show is really emphasizing that, you know, we may think of art and science as these two totally. separate things that have nothing to do with each other. But, you know, the longer I've worked here and worked on these kinds of stories, I've realized that these things are just so intertwined and influence each other and our reality in really concrete ways. Yeah, I love this idea. Maybe we can hear a clip of the show. Yeah. I'd love to play this bit from our episode about

a group of illustrators and scientists who made comics about invertebrate butts. Yeah, I remember this one. Let's listen. Turns out, Maureen isn't the only one fascinated with invertebrate butts on Twitter. I thought, oh my goodness, I have to do a comic about an animal with a zillion different butts. She started a small document with some of her favorite butt facts, threw it into the chat, and the other members started adding to it. I think at one point I said, oh no, we've opened Pandora's butt. Because there were so many different pieces of information flying in this chat. It's worth listening to just for Pandora's butt, alone.

I agree. There's so many other quotes that I've stuck in my mind from that segment. So basically, if you listen to Science Friday and you really connect with our art stories, I think you're really going to like the show. And we'll actually be dropping the first episode in the Science Friday podcast feed tomorrow on Saturday. But if any of this sounds appealing to you, check us out, subscribe to Universe of Art, wherever you listen to your podcasts. We have a couple episodes already waiting for you there, and you can learn more about it at ScienceFriiday.com slash art. Thanks so much, Dee. Looking forward to listening to the podcast. Now, we've got to take a break when we come back tackling misconceptions about something half the

world does, menstruate. That's right after this. This is Science Friday. I'm John Dankoski. And I'm Maddie Safaya. I'm going to say something, and I want you to pay attention to how you feel when I say it. Menstrual blood. Yeah, periods. Maybe you just felt a little uncomfortable. But it doesn't have to be that way. Periods are just one of the many biological processes out there in the world. Half the population has periods. But menstruation. is seriously understudy, and that leads to a lot of misconceptions. Lucky for us, there is a new book all about the biology of menstruation, its history, and its future. My guest is Dr. Kate Clancy, biological anthropologists, and author of period,

the real story of menstruation, based in Urbana, Illinois. Welcome to Science Friday, Kate. Thanks so much for having me. I'm excited. I'm excited. Okay. So many of us who have periods are taught that they're like kind of gross or useless or they shouldn't be talked about. But at the beginning of your book, you write, menstruation is a wild process that should captivate and delight. Can you make a case for that and why you feel that way? I hope I can because I certainly did spend an awful lot of words trying to do that in the book. So I'll try to give you the condensed version here. The thing that is so interesting

to me about periods is that it is something that occurs so regularly. It is this incredible process, the cyclic process, right, of growth and differentiation and regression that happens, you know, upwards of 400 times in a lot of people's lives. And it's, what's incredible to me is that there aren't a ton of processes like this where you actually see the effluent, you see the output, you know, and can kind of engage with it in a really nitty-gritty way. There's a reason that phobias of blood don't tend to occur in menstruating people. And it's because we are so directly engaging with blood and clot and other lymph and other things all the time. And so we get this like very real time, granular sense of what's happening in our bodies. And I think the fact that we get to

know that this process is happening in the body, but then also see some of its output and see how it changes over our lives is just fascinating. Yeah. And I think it's important to talk a little bit about why menstruation is so understudied. I know that's a big question. But talk to me a little bit about that. I mean, there are a couple of different reasons why menstruation is understudied. One of the big ones, of course, is menstrual stigma itself, which is a really persistent issue within Western science. The way that stigma tends to manifest is through silence, through lack of communication, through removing people from daily life who might be experiencing menstruation. And so there are a lot of ways where we just haven't even known what questions to start asking because so many people

have such limited ideas about what it even is. The number of times I've encountered people who don't know the difference between menstruation itself and a menstrual cycle is huge. So I usually have to coach people who are research participants on my studies. And I'll say, okay, so about how long is your menstrual cycle? And they'll usually say, four or five days. And I'll say, well, actually, you're probably telling me how long your menstrual period is. Your cycle is like first day of one period to the first day of the next. And it just sort of blows open that like even some of these really basic things that as a scientist I've come to take for granted, these small language shifts are things that we don't even have in our regular discourse. Right. I mean, tell me a little bit more about some of those

like big misconceptions that you wanted to dissuade in this book. I know there are a lot of them, but give me like your favorite. I think, you know, one of the biggest and most persistent myths, and I think it's still very much in our popular understanding of periods, even though I don't think that this is where the science is anymore, is that periods are about removing bad things from your body. You know, it's about flushing out the system, getting rid of toxins. You know, there's a lot of different ways that people talk about it, but it's kind of about removing yucky stuff. And really, the effluent is sort of this side effect of the cycling itself. And so really, instead of thinking about it as, you know, you're removing gross stuff from your body, actually what you're undergoing is this

really amazing healing process of renewal of your uterus every, let's say, you know, anywhere from 25 to 40 days. I want to focus on this one idea you talk about a lot in the book. And that's this idea of like a quote, normal period, that you can kind of find some representative average cycle amongst the menstruators. Can you explain that to me? Sure. There's sort of this dorky thing, you know, of understanding like statistical distributions or statistical averages that we probably have at least a little bit of familiarity with from math and stats classes in school. And it's this idea you take a whole bunch of numbers and you figure out where the mean is. The problem is, is that, you know, using a mean to have any type of biological meaning kind

of presumes that there's going to be a normal distribution, meaning like a more or less equal number of people on either side with the majority of people hovering around that mean. But that's not actually how a lot of measures in the menstrual cycle work. You can see, you know, like a bimodal distribution. So, you know, like a lot of clumping at the low end and a lot of clumping at the high end. The mean is not actually all that informative for a lot of things. And we do lots of things statistically to handle it. We like things called log distribution and other stuff.

But at the end of the day, it's not normally distributed. So understanding an average and constantly representing that as the norm is inaccurate. And I think it's important just this idea of normal for us to examine it. I mean, in many areas of science, including the science of menstruation, normal is based on a very specific population, right? It often excludes people of color, trans folks, disabled people, basically anyone outside of this like white cis population that science, Western science, really likes to focus on. I mean, how does this harm our understanding of periods? Right. In exactly the same way that it does in all of these. other ways, right? If you take a selected group of people, a sample of people that's drawn from a small proportion of, like you said, often cis, white, straight, able-bodied, you know, other types of potentially privileged bodies, we take that average and then we say, that's what normal is. And all of you must conform to that or else we're going to put you in the pathological bucket and you don't ever get to be

in the healthy bucket. Then that means that everyone ends up developing these really skewed ideas of what it means to be healthy or normal, including the people who are in that self-selected group because of the fact that, you know, this normal distribution thing is kind of a farce to begin with. So it's actually harmful for everybody. Right. I remember being like, I got my period like a little bit later in life and all my friends had it. And I was like, man, I guess I'm a late bloomer and like felt weird and weird things about my femininity. And that is true for a lot of people.

Mm-hmm. One of the papers that I read as I was writing this book was a study that asked people, who, you know, were adults, asked, when did you first get your period? And did you feel that you were early later right on time? And pretty much everyone thought that they were early or late. Nobody thought they had actually gotten their first period on time. And yet the difference between the age ranges of the people who said, oh, I got my period so early or so late was about half a year. So it was like nine to 11 and a half were saying, oh my gosh, my period was way too early. And then 12 to 14 was saying, oh, no, my period was so late. So that means nobody gets to live within that norm and feel like

they're normal. And I think it's also, you know, when we are talking about it, it's like comparing ourselves to this, you know, this like ridiculous standard. But you talked a lot about in this book about how we just don't talk about it. And that's a very like Western medicine, Western view of menstruation. How does this compare to other cultures? Is there like a culture where you're like, like, man, I'd really like to menstruate in that culture. I think what I would say is, you know, there is so much more variability out there in terms of how different cultures think about and interpret periods culturally and biologically. And I think one of the biggest harms of Western science and Western anthropology, you know,

I'd say as an anthropologist, is that we take our lens and our way of seeing the world and then we say that we're being objective and pretend we don't. have that lens. Then we go to all these other populations and we're informing our interpretation of what they're doing with our lens. So for the longest time, we saw menstrual seclusion practices. So, you know, going somewhere when you have your period, somewhere away from other people as negative. And we were like, oh my gosh, those terrible sexist populations. And now we've seen there's so much more variability. There are some times that menstrual seclusion practices are harmful, are problematic, but there are many, many, many more across many other populations and many other cultures

where menstrual seclusion is about getting a little bit of a break, you know, concentrating your power, taking some time to yourself. And that's a really different way of thinking about periods and certainly one that I would love to adopt. Absolutely. Absolutely. I remember you talking in the book about how it would be like nice to like hang out with other menstruating people and take a break and maybe talk about what you're experiencing and being very uplifting. lifting. And I was like, wow, that is so much different than what a lot of us experience. Right. And instead, what we do is we pretend that it's not happening. Okay, Kate, I have one more thing I want to do. It's a lightning round. So brace yourself. I want to tell you, like some things that

I've heard about periods, I want you to tell me, and I know this is going to be hard because we're going to leave these caveats, like true or false, right? I'll do my best. Okay. Periods sink up. Like when a group of menstruating people are living together or spending a time together, there's like a uterus that takes over and they all sink up. Is that real or not real? It's false. Okay. All right. What about PMS? This idea that everybody gets like really moody or like experiences these hormonal shifts that come out as like emotional, you know, whatever you want to say before your period. Is that real? It's not universal. So it's false in the sense that it's like universally experienced by every person who has a menstrual cycle, but do people experience mood

changes premenstrually? Absolutely. Okay. And then my last one is that we've touched on a little bit, but I still want to ask you this idea that menstrual blood is like useless. False. Okay, Kate Clancy, that is all the time we have now. I would like to thank you very much for coming onto the show and talking with us. Oh, it was awesome. Thanks for having me. Dr. Kate Clancy, biological anthropologists and author of Period, the real story of menstruation based in Urbana, Illinois. You can read an excerpt from this book on our website, Science Friday.com slash period. And now it's time to check in on the state of science. This is KERNO, St. Louis Public Radio, KKMD News.

Local science stories of national significance. An experiment is happening in a South Georgia forest, a startup climate. claims that hybrid poplar trees will be able to sequester tons of carbon from the atmosphere. What's more, this is the first time a genetically modified tree has been planted in a U.S. forest. But what exactly do we know about these trees? And will this carbon capture project actually work? Joining me to talk through this story is my guest, Grant Blankenship, is a reporter for Georgia public broadcasting based in Macon, Georgia. Grant, welcome to Science Friday. Yeah, thank you so much for having me.

So first of all, tell us what exactly are these trees genetically speaking and how exactly were they made? Well, so what you're starting with is actually a pretty common tree. It's a hybrid of two poplars that are native to Europe, the white poplar and the quaking aspen. So here the researchers cloned one of these female poplar hybrids a bunch of times. And then they took what's a common soil bacteria and used it to carry genes from plants like pumpkin and creosote into the gene. genome of these tiny poplar clones. And so the idea here is that by restricting the expression of that one gene, the trees would become better at making their own food. And in turn, they would really pack on the biomass. So what exactly is the carbon sequestration that's being promised with these trees? Because we hear an awful lot about attempts to sequester more carbon from the atmosphere. Right. So, you know, Living Carbon is the name of the company that's selling these trees. And they make

two claims about them. One, they promised that this, this genetic, manipulation of photosynthesis is going to make the trees grow twice as fast as unmodified poplars as the ones that haven't had this transgenic overhaul. And then remember, you know, photosynthesis trees sort of breathe in carbon dioxide on the front end of photosynthesis. So the company's second claim is that as these trees are growing twice as fast, they're also adding almost 30% more carbon-based biomass than in these unmodified. trees. Wow. So these are some pretty big claims. This is not peer-reviewed stuff. Are these just, are these estimates just coming from the company? I mean, how accurate are these? Right. I mean,

so far, these estimates are just coming from the company. This isn't something that's been peer-reviewed in a journal. And it's also from a laboratory experiment, very controlled conditions where they've observed these effects, this product. Yeah, I mean, so far, there really isn't any proof from an actual forest planning that these trees are going to do what the company says they will. This is Science Friday from WNYC Studios. So, Grant, this is important to note, this isn't just a carbon sequestration effort. This is being done because people want to harvest these trees for the lumber markets. So what do we know about that? Right. Yeah. I mean, this is really, really being driven by market incentives, right, the free market economy and all that. So the first thing to understand is that they're

two very different parts of the market, these trees. The first is just what you'd think. It's wood. My assumption is that a mill is probably pretty agnostic about the genome of your tree. You know, wood is wood. But you should know that when you're in one of those big box hardware stores and you're in the lumber aisle, the odds are really good that what you're looking at, the plywood there, is poplar wood. The second market in question here is the carbon credit market. So very broadly, that's where if you're a carbon polluter, you can buy someone else's sequestered carbon and sort of offset your misdeeds. The hope here is that these new trees are going to amp up a forester's ability to sell carbon credits on that carbon credit market. That's really the hope of Vince Stanley, the landowner who's participating in this experiment.

He would absolutely love to make extra money on carbon socked away in tree trunks, right, long before he ever cuts them down. going to pay me a sum of money every year and I get to harvest the timber, give me that, give me that all day long. Yeah, and so the deal is here in the South, it's like 90% of our forest land is privately owned. Living Carbon has set up shop in South Carolina, and they're really betting that there are lots and lots more foresters in the South and with the same thing that Vince Stanley does. Are there concerns, Grant, about sending out these genetically modified trees into the world, planting them in forests, and then maybe having them,

spread beyond our control. Well, yeah, I mean, here's the crazy thing. These trees are so new. It's hard to know if people even know enough about them to be concerned yet. Scott Merkel is a forest biologist with the University of Georgia's Warnell School of Forestry. For years and years, I've been telling people who ask about transgenic trees in the United States.

There is no transgenic forest tree that's been given non-regulated status in the United States. But here we go with these hybrid poplars. And they're already out there, and I don't think hardly anyone knows about this. And these trees aren't regulated because Living Carbid submitted their trees to the USDA just two months before current rules on reviewing genetically modified plants took effect. They were sort of grandfathered into the older rules. In the original tree, that hybrid poplar, it's already an invasive species in a number of U.S. states, even in parts of Georgia.

And so Scott Merkel, the forest biologist, he says, even if the new trees are all female colognes. The pollen they need to seed could come from these garden variety poplars that are already invasive on the landscape. He says, of course, you know, he can't be sure that that's going to happen, but it's really something worth considering. It's such an interesting story. Fascinating technology. And as we used to say on the program, maybe a good thing, bad thing about the environment grant. I'm glad that you're covering it. Thanks so much for joining us. Yeah, my pleasure. Thank you for having me. Grant Blankenship is a reporter for Georgia public broadcasting based in Macon, Georgia.

We have to take a break, and when we come back, how exactly does anesthesia work? Yeah, we'll talk about how anesthesiologists create these custom drug cocktails to make sure each patient goes under. This is Science Friday. I'm Maddie Safaya. And I'm John Dankowski. If you've ever had surgery, you've probably wondered about how anesthesia works, or maybe even you fly to wake at night. anxious about going under. I know I have. Now, if you've ever been there, I'm sure you remember it. It's right before surgery. You get rolled into the operating room. The anesthesiologist tells you to start counting down from 10, and then the next thing you know, you're awake in the recovery room. You don't

remember anything that just happened to you. How exactly did the anesthesiologists manage to get you safely into that state, and then back out again? Joining me now to give us a crash course in anesthesia are my guests. Dr. Louis Sussiologist. Son is a professor of anesthesiology, perioperative, and pain medicine at Stanford University Health, based in Stanford, California. And Dr. Guni Shakur is an anesthesiologist and director of the Human Rights Impact Lab and medical director of Weil Cornell Center for Human Rights at Wild Cornell Medicine, based in New York, New York. Welcome to Science Friday, both of you. Thank you. Thanks for having us. And I should let you know that this program was taped on Zoom in advance, and so we're

to hear a lot of great questions from our audience. Dr. Corr, I want to start with you, and you know, we typically think about it when we talk about anesthesia about going to sleep. So first of all, what's the difference between going to sleep and going under anesthesia? It's a great question and one that we receive a lot from our patients. There are some critical differences between receiving anesthesia and going to sleep. When you go to sleep, you have the ability to form memories to wake up to feel pain. If, for example, while you're sleeping, your dog scratches your leg or your cat scratches your leg or a child wakes you up, you will remember that. You can wake yourself up. You might remember that you feel thirsty or you have to go to

the bathroom and you'll wake yourself up and you'll do those things and you'll fall back to sleep. Under anesthesia, you don't form memories in the same way. You don't remember things in that same way and you shouldn't feel pain in that same way. So there are critical differences between sleep and anesthesia. Okay, so why is that? Why don't I feel pain? Why don't I remember things? What are you giving me exactly? Well, anesthesia isn't like a pill that's given or a machine that's turned on and off. There are several different anesthetics that are given that are carefully titrated to a person's individual needs during a a procedure, we monitor and sometimes control a person's breathing or their heart rate or rhythm

looking at an EKG, their blood pressure, their blood oxygen and carbon dioxide levels. We monitor by pulse oxymeter. We look at concentrations of anesthetic gases in the body, fluid levels in the body temperature, and sometimes brain activity even. We give several different medications that affect each of those things. So it's a combination of medications that really helps provide all of the things that you need to be under anesthesia. So Dr. Sun, then what exactly do you do when you're making this mix? How do you decide how much of this agent and how much of this are we going to use to get this person into exactly the state that we need them to arrive at?

That's what we term balanced anesthesia. And so what that means is that the cocktail could differ. slightly from person to person, and we do want to tailor what we give according to the person's age, that person's physiology, you know, pain or stimulation level that we anticipate with the type of surgery that they're going to undergo. So we tailor all those things to achieve what we call amnesia. So in other words, they don't have a memory or recall the event. Anogesia, which is achieving a painless state so that they're comfortable undergoing surgery with overdoing it with the drug dosages. And also that they're basically immobile for the surgery.

And the doses, as you say, would be different depending on your age. But they could also vary, depending on, say, if you take drugs, if you smoke, if you are on some sort of drug regimen for some other health issue, right? Exactly. Yeah. People, for instance, who drink alcohol or people who are on, say, a cannabis or an opioid medication chronically will have a different tolerance level. threshold for the medications that we give. There are drug-to-drug interactions to consider as well. There's some interactions that can be deemed to be synergistic, meaning we have to reduce the dosages of certain medications we give,

versus there are medications that really don't interact well and could produce some very dangerous side effects that we have to watch out for. So it's about pharmacology as well. I think that we've all had the experience of a doctor during a regular physical exam asking a question about how much we drink over the week and we think should I tell my doctor how much I drink over the week? But this is an example, Dr. Kor, that really you should. You should tell people, okay, here's other medications I'm on. Here's some things you need to know about me because it's going to be harder for you to do your job if I don't. I think there is

sometimes a fear of telling your doctor the truth. We all want to present our best selves to our doctors. But I think it's really critical that your physician knows what medications you've been taking. It's not a problem if, let's say, you are a smoker, that your surgery is necessarily going to be canceled. That's not necessarily a problem if you use marijuana recreationally, but those are things that we need to know so that we can provide you the best care. And then, of course, Dr. Sun, there are different surgeries that are very different. For instance, Many people know that during brain surgery, there's a portion of the procedure that you are out for, but there's another portion of certain procedures where the physician, the surgeon, will want you to be awake during what's happening.

Those procedures are referring to in the realm of neurosurgery are called awake cronyotomy. Those are surgeries where going around the very sensitive motor and speech areas, for instance, where we really want to have a real-time testing of your brain function. So in that case, the anesthesiologists will need to blend their cocktails carefully so that they're relieving the patient's anxiety and the medication will be short-acting enough so that, you know, they could be deep asleep when they need to and they can wake up when they need to. I will say one of the big fears, and I'm sure that some of our listeners to this program will have some of these same questions. is that people are worried, Dr. Corr, that they're going to be knocked out, unable to move,

but they'll still be able to feel what's going on. First of all, is that possible? Does that ever happen? How often does it happen if it does? It's a great question, and I'm so glad you asked it, because I do get that question a lot from patients, especially if they've watched that horror movie called Awake, which I have not seen myself for good reason.

I'm not really interested in watching that, thanks very much. You should. If this is not a recommendation, this is an anti-recommendation. Okay. The chances of being awake during anesthesia or having awareness under anesthesia are exceedingly low. There's a lot of fear because of movies and media, but in reality, awareness under anesthesia occurs in less than 0.1 to 0.2% of cases. So it probably be more dangerous to walk a across the street. The surgical procedure can be associated with lighter anesthesia depth. So, for example, trauma surgeries or emergency surgeries or cardiac surgery with bypass might contribute

to that 0.1 to 0.2% number, but it's still, again, exceedingly rare. There's a lot of monitoring that anesthesiologists do in this day and age to ensure that somebody is not awake, not forming memories and not feeling pain, which are really critical components of anesthesia for surgical care. Dr. Son, I guess I'll tell a personal story here. I'm one of those anesthesia phobic people because I had a couple rough experiences. I remember one time I came out of surgery, fairly simple surgery for hernia. I felt drugged for days.

It was terrible. I was throwing up forever. And then there was another one where I woke up and I was thrashing side to side. there were orderlies and nurses holding me down. What do you think causes that? Yeah, and sorry, John, to hear about those experiences. I think, you know, it just really speaks to the variability between people in terms of, you know, how their bodies receive the anesthesia medications and also really how anxious you are

before you receive general anesthesia. So, you know, for instance, what we observe is that patients who are younger, healthier and extremely anxious before they are put under can wake up quite anxious as well. So I wonder that partially explains the second circumstance because you had a bad experience the first time around. You know, and speaking to how the body handles side effects of medications, you know, some people are more prone to being nauseous afterwards and also things like, you know, getting confused afterwards and feeling very groggy afterwards.

It's dose dependent, but it's also person and genetics dependent as well. This is Science Friday from WNYC Studios. If you're just joining us, I'm talking with anesthesiologist, Dr. Ganesha Kor and Dr. Louis' son about how anesthesia works. And now we're going to take a few of your questions. Suzanne is with us, and Suzanne has a question about people's age in relation to anesthesia. Suzanne, go ahead. Thank you for taking this question.

My mother-in-law is about to have surgery. She's 90 years old and very concerned about going under anesthetic. She's worried about her brain. She's worried about waking up. She's worried about all kinds of things. So the question is, do risks and side effects increase as people age? Thank you. That's a great question, Suzanne.

Dr. Kor, would you like to take that first? Sure. Thank you for the question. And I hope that she does well. We provide anesthesia safely to people of all ages, people who have many comorbidities who might have heart disease or kidney disease, we can do that safely. And I think talking through those preexisting conditions with your anesthesiologist is going to be a critical component of providing safe anesthesia. One of the things that we know about anesthesia is that

the doses necessary to provide surgical anesthesia change with patient-specific conditions. We know that by each decade of life, anesthetic requirements change. And so that's something that is well known in anesthesiology, that we can actually shift as we care for her. Suzanne, thanks so much for that question, and best of luck to you. I really appreciate you asking it. Terry has a question for us about our brain's long. term reactions to anesthesia. Go ahead, Terry. You're on the show. Hi there. Thanks for doing this.

I'm just curious because some of us have had brain injuries and concussions. And then when we have surgery, I'm actually kind of worried about my brain. I had a shoulder replacement in October. And then three months later had to have a knee arthroscopic surgery. So my brain handled the shoulder replacement fairly well. You know, it was kind of mushy. stuff, but it kind of recovered. But boy, after the second one, my brain is just mush, and they have to redo the knee, and I'm just terrified. So how does that kind of impact work with the anesthesiology? That's a great question, Terry. And I'm glad we've got some experts here to help you through that. Dr. Son, why don't you try to help Terry through that? Thanks for the question, Terry,

and I really hope your second knee surgery goes well. Of course, previous traumatic brain injury is a good consideration for our administration of anesthetic medications and also in terms of the hemodynamic or blood pressure goals that we want to maintain during surgery. You know, one of the things that we really want to be cognizant of is make sure that the brain gets enough blood supply and also, you know, sometimes in avoidance of being very heavy-handed with certain classes of sedation medications that may make people a little more prone to being confused or delirious during the parooperative period. You know, of course, all of those have to be balanced out with the need to provide you with

the best pain killer regimen that we can for that type of surgery because it is a procedure where we don't want you to be in pain afterwards, which means, you know, doctors are probably more likely to employ what they call multimodal pain management type of type of regimen. Now, we've been getting this question from a few folks who submitted before this event, and they're all asking, why does it seem like no time has passed after waking up from anesthesia? Dr. Corr? So while we don't know the exact, like we talked about earlier, molecular mechanism,

specifically of general anesthetics, we do know in some ways how this anesthesia works. And we know a lot about how memory formation is disrupted. under general anesthesia, the communication essentially between nerves at the synapse is disrupted. So you're just not forming memories. You're not processing time. You're not remembering things in the same way when you're awake or when you're sleeping, like we talked about earlier. If you're under general anesthesia and if it's sedation, you may be in and out of the anesthesia. So I think both memory formation and the processing of time can be confusing to a person. It might not be what it seems.

So if somebody says I was aware under anesthesia, one of the first questions I'd have is, was it general anesthesia or was it sedation? With sedation, particularly light sedation, we would expect that you might be hearing things. You're not completely asleep. And so time and memory formation are shifted. Dr. Sun, to close things out, we've talked about this a little bit, but there are going to be some people, some of the folks who ask questions, me, for one, who might be nervous about an upcoming surgery. So what should they make sure to discuss with their anesthesiologist beforehand? What can you tell them to sort of put their mind at ease about the process?

What I often tell our patients is that we've done a few of those procedures here before. which is a bit of a joke because we grossly underestimate the amount of expertise that is required to do the job and to do it well. Some of the things that we discuss, of course, patients are always entitled to ask about, you know, the degree of risk they're taking in pursuing surgery under certain anesthesia techniques. For some procedures, it might be safer to do a sedation rather than a general anesthesia or a nerve block. rather than a general anesthesia. There are some cases or general anesthesia might actually be safer than the other modalities of anesthesia. So I think patients should always be open to talking about the risk and benefits of different

anesthesia procedures and also just really coming with an open mind. I let patients have a free shot at asking me anything. And so, you know, over the years, I've received many different types of questions and I've always been very happy to address them. Well, I'd like to thank you both very much for addressing all these questions from us. Dr. Louise Son is a professor of anesthesiology, perioperative and pain medicine at Stanford University Health, based in Stanford, California. Dr. Ganesha Korr is an anesthesiologist and director of the Human Rights Impact Lab

and medical director of Weil Cornell Center for Human Rights at Wild Cornell Medicine. She's based in New York, New York. I'd like to thank you both so much for doing this. Thanks for answering all these questions. I feel like I know a lot more than I did before. Thanks so much for having us. Thank you. Some of the folks who helped to make this show happen this week include

Grants Managers Jordan Smudjik and Jason Rosenberg, Director of Audience, Ariel Zich, and Experiences Manager Diana Plasker. B.J. Leederman composed our theme music. If you missed any part of this program or would like to hear it again, subscribe to our podcasts. You can email us too. The address is SciFry.

at ScienceFriday.com. I'm John Dankoski. And I'm Maddie Safaya. Have a great weekend.