How CPR Works

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You have a golden opportunity to make yourself into a worthwhile human being simply by learning how to perform CPR. The chances are you'll never need to use it, but knowing how just in case never hurts. Listen to this episode to get you primed to take a course on real-life life-savin'.

Josh Clark: Hey and welcome to the podcast. I'm Josh Clark with Charles W. Chuck Bryant and you put the two of us together and it doesn't matter what, you're still gonna come up with Stuff You Should Know.

Chuck Bryant: That's right. For better or for worse.

Josh Clark: That's right, man. You are stuck with me.

Chuck Bryant: How are you, sir?

Josh Clark: Tickled. How are you?

Chuck Bryant: I'm great. I'm ready to save some lives with this here podcast today.

Josh Clark: You know, it's entirely possible that we could. Like we could tell somebody how to do the basics of CPR and we should COA and I see you have it written down. If you are interested in being an above average human being by taking the time to be taught how to save someone's life using Cardio Pulmonary Resuscitation, you should do that.

Chuck Bryant: You totally should.

Josh Clark: Genuinely you are a better person for that. You can go to, it's the American Heart Association's website. Type in your zip code and it will bring up tons of free classes that you can go to at your convenience and become certified in CPR.

Chuck Bryant: You should do that because not only could you maybe be a hero and save some strangers life, but if you care about the people around you wouldn't you love to be able to save their life at a moment's notice?

Josh Clark: Exactly.

Chuck Bryant: To me it's almost like giving blood. It's like almost a human requirement in this day and age.

Josh Clark: You give blood?

Chuck Bryant: Of course, I do.

Josh Clark: I keep my blood. Umi gives blood. She's always like don't you want to too? I'm like nah!

Chuck Bryant: You should give blood.

Josh Clark: I know I should. I don't even know what my blood type is. There's a pretty good reason to give blood.

Chuck Bryant: Just to find out?

Josh Clark: Yeah, can you test that too?

Chuck Bryant: Yeah, how am I doing? And where's the Nutter Butters?

Josh Clark: Yeah, that's a bonus too. I always feel guilty when Umi shares her Nutter Butters with me. I'm like I didn't earn these, these are yours.

Chuck Bryant: But does she bring them home or do you like go and drop her off and sit with your arms crossed while she gives blood? All right.

Josh Clark: You ready?

Chuck Bryant: Yeah, man, let's CPR it.

Josh Clark: Oh, so we're still in the middle of COA like this is in no way intended to replace one of those classes. If you listen to this podcast, you're not certified pal. You're possible a bigger danger than before.

Chuck Bryant: You're certifiable, but you're not certified.

Josh Clark: So this is intended to I guess maybe just kind of go over the absolute basics of CPR and hopefully peak your interest enough to get you to go out and take a real class. That's what we're doing here today.

Chuck Bryant: Yeah, I took when I life guarded I obviously took CPR then, but it's been a while. I was like 20 years old.

Josh Clark: So why are you always walking around in nothing but a bathing suit?

Chuck Bryant: I don't know, man, laying here with a whistle.

Josh Clark: Yeah, I thought you still were a lifeguard. What are you doing then?

Chuck Bryant: I don't know. I just like to keep it skin.

Josh Clark: Malibu style.

Chuck Bryant: Malibu style. Skin to win as my friend says.

Josh Clark: All right, you ready?

Chuck Bryant: Yeah.

Josh Clark: Okay, so are you familiar with the heart?

Chuck Bryant: I am.

Josh Clark: Well then, this won't come as any surprise. The heart has a little part of it that's called the pace making area, the Sino atrial node. The SA node. The SA node produces a burst of electricity that stimulates the muscles in the heart to cause it to pump. Usually about on the low side, once a second. That would mean that you would have a heartbeat about 60 beats per minute which is low on the - that's good for resting. If you're active, it's a little low.

You have this thing, this SA node, that produces electricity and it produces it in a reliable rhythm, but certain conditions say like dehydration, stress, and all sorts of things can cause your SA node to go a little haywire. All of a sudden it's shooting out bursts of electricity in a really weird pattern. No pattern at all and when that happens usually your heart, the pump weakens. The pump mechanism weakens. So it's going dih, dih dih and it's not really beating at all. I mean, it's beating, but it's not really pumping any blood. What you are in the middle of is called sudden Cardiac Arrest.

Chuck Bryant: Yes, and that is different this article points out than a heart attack. If you have a heart attack that is something that happens very slowly over time and then you will eventually have the heart attack. That is sort of the end result of that slow build.

Josh Clark: And usually you're heart's not pumping blood because it's backed up. With a sudden cardiac arrest, your heart is going haywire and it's trying to pump blood, but it doesn't have the strength to anymore because the electrical current is being distributed incorrectly. Are you familiar with defibrillators?

Chuck Bryant: I am. You know, they have one here in the office.

Josh Clark: Well, they save lives. If you hit somebody with an AED, with a defibrillator which is another thing you need to be trained on before you really try using it.

Chuck Bryant: Clear! That's all I can do.

Josh Clark: Right, and you want to be clear too. You don't want to be touching the body when that goes off, but you put one paddle over the heart and one paddle over the other side so the middle of the chest and on the left side of the person. You shoot the charge through and what you're doing is not starting the heart. You're actually turning the heart off.

Chuck Bryant: Yeah, I think everybody that doesn't know about the defibrillators - boy I knew I was going to have trouble with that.

Josh Clark: It's a tough word.

Chuck Bryant: I think most people think that, yeah, your heart stops and it kick starts it back up. Not true.

Josh Clark: No, it turns it off in the hopes that it will start back up at a normal rhythm.

Chuck Bryant: Yeah, like it resets the pace.

Josh Clark: Right, and it frequently works, but it is just so surprising to me. It's such a gamble it's like well, the heart's not doing very well right now so we're just going to shut it off and see what happens.

Chuck Bryant: Yeah, that is weird. Sadly, if you have sudden cardiac arrest; you have about a 5 percent chance of surviving because it is out of the blue. It can occur to a very healthy person. It can occur with young people, old people, and any kind of person.

Josh Clark: Yeah, it's not just like heart disease. It's a part of heart disease frequently, but like I said it could result from dehydration when your electrolytes are off.

Chuck Bryant: Yeah, the good news if you have a heart attack or a myocardial infarction is that you have a pretty good chance of surviving that actually and turning your life around with diet and maybe get some stints thrown in there.

Josh Clark: Teaching English to prisoners.

Chuck Bryant: Maybe so, but all of this is leading up to the fact that CPR is something that you can increase somebody's chances who has sudden cardiac arrest.

Josh Clark: Right, here is the whole point of CPR. The moment somebody drops dead in front of you or you come across somebody who's dying or dead or unconscious I guess is a better way to put it. Like time is of the essence, they're blood is no longer pumping through their body. Their brain is becoming starved. They are at risk of becoming brain damaged and usually here there is like a five minute window where you really have the opportunity to save someone's life.

So whether it's somebody is running to get the defibrillator or waiting for 911 to arrive, waiting for the paramedics to arrive. The whole point of CPR is to pump blood to through the body to keep this person in this basic minimal artificial state of life, so that real medical help can be administered.

Chuck Bryant: Yeah, you're just trying to stave off death basically for as long as you can until you can get some help.

Josh Clark: And this is nothing new, right?

Chuck Bryant: No, it's not. There's a little bit of history that I dug up. Apparently, the prophet Elisha in the Bible is described as performing mouth to mouth on a child. Who knows what that meant? In 1740, the Paris Academy of Sciences -like you know it was a Bible that said he placed his mouth upon the child's mouth and stuff like that, but who knows if it was CPR.

Josh Clark: Did they describe what was wrong with the child?

Chuck Bryant: You know, I don't know. The child was not doing well. In 1740, the Paris Academy of Sciences first recommended mouth to mouth for drowning victims.

Josh Clark: Yeah, because apparently up to that point it was like oh, you're drowned so that's it for you. We're not even going to try anything. Maybe we'll hit you with some sticks.

Chuck Bryant: 1891, Dr. Frederick Maass performed the first documented chest compressions on a human. Sadly, it was 23 years later or 24 years later that Dr. George Crile first reported a successful resuscitation from chest compression.

Josh Clark: Well, yeah, it was a work in progress.

Chuck Bryant: It very much was because it wasn't until 1956 even though mouth to mouth was a thing that Peter Safar and James Elam were credited with inventing as modern CPR in the 50s and 60s is where they really perfected it. Like 1960 is when CPR was officially named and developed.

Josh Clark: Right, and then shortly after that came resusci Annie and the little kid with the jumpsuit.

Chuck Bryant: That's right. All right, so that's just a little background.

Josh Clark: Right, so it's been around for a little while, but the point has always been the same. Somebody's in an emergency situation and you need to basically stave off death. So, Chuck, let's say that you come into the podcast recording booth and you see me just laying on the floor. What are you going to do/

Chuck Bryant: Well, I would scream and cry out in agony and shock, firstly. I'd be very upset. Then the first thing I would do would be to say, Jerry, for God's sakes put down the beer and call 911 immediately.

Josh Clark: I would suspect that Jerry would have known I was in here unconscious the whole time.

Chuck Bryant: Well, that's why she's drinking the beer. She's celebrating.

Josh Clark: She got it from my desk.

Chuck Bryant: So, yeah, the first thing you want to do is call 911 and get some experienced help there from -

Josh Clark: Well, that's after you've poked me in the face and said Josh, Josh and you looked at my chest seeing that it's not rising or falling and noted that I'm a little more blue than usual.

Chuck Bryant: Yeah, I would yell to call 911 first, personally.

Josh Clark: Okay.

Chuck Bryant: But, yeah, you're supposed to check the person. If it's a child or baby, they say never ever shake them. Just stroke them to see if they respond.

Josh Clark: Like baby.

Chuck Bryant: Do something like that to see if you get a response and if it is clear that this person is not breathing and don't look like their heart is beating.

Josh Clark: Another big one is that chest rising and falling because if you come across somebody and they're just dead drunk, that's different from dead.

Chuck Bryant: Yeah, that's true. I've seen that too. Not from you. There's different types of CPR and depending on how trained you are is which one you would undertake.

Josh Clark: Right, so you've determined I'm unconscious. You don't know what's wrong with me, but I'm blue. Jerry is off dialing 911 finishing her beer. You are - let's say that you have never done anything but heard of CPR. What kind of CPR should employ?

Chuck Bryant: That means, and this is from the Mayo Clinic and they know a thing or two about this that would be what's known as an untrained person. I would only perform the hands only resuscitation.

Josh Clark: Which we'll describe in detail. And then let's say that you've had some training before, but it's been a while.

Chuck Bryant: Well, that's me. I'm trained, but rusty. They say still just use the hands only.

Josh Clark: Don't get cocky.

Chuck Bryant: Yeah, don't think you remember all that lifeguarding stuff.

Josh Clark: Let's say you had just gotten out of a CPR class and this happened. You'd be trained, but confident.

Chuck Bryant: That is right and that means that you can perform full CPR with rescue breathing and that's great. It means that you are 100 percent confident and you are delivering 100 percent of your knowledge.

Josh Clark: Right, and then if you have access to an AED - where is the one in this office?

Chuck Bryant: I know where it used to be until we redid the kitchen.

Josh Clark: Oh, was it in there?

Chuck Bryant: It used to be in the break room.

Josh Clark: Oh, yeah, it was. That's right.

Chuck Bryant: Right by the "don't massage your coworker" poster. What's that called? The warning basically. Inappropriate touching.

Josh Clark: I always was caught my attention was always gotten by the labor laws poster for some reason. I don't know why.

Chuck Bryant: That's where it was. I don't know where it is now. It's probably in our new smaller break room.

Josh Clark: Yeah, you're probably right. So if you have access to an AED, you want to actually deliver one shock and then start CPR.

Chuck Bryant: That's if you know absolutely you're in training and you know what you're doing.

Josh Clark: You don't want to waste time looking for a pulse. They used to always say check for a pulse.

Chuck Bryant: Don't bother.

Josh Clark: No, because they found out that people were spending a lot more time than they should trying to find a pulse and just basically wasting time. I think basically if you can look at somebody and see that their chest isn't moving, you don't need to look for a pulse.

Chuck Bryant: Yeah, I mean, if I was on the ground the last thing I would want to hear as I'm fading out is I can't quite tell. Is that a pulse? Come here does that feel like a pulse to you?

Josh Clark: Would you call this pulse thread?

Chuck Bryant: Yeah, and you're down there going just please start compressions.

Josh Clark: Right. So the American Heart Association said let's just go around this and really focus on the chest compressions. Over time, they've - in 2010, they really changed everything and said just do chest compressions. Anything else is like additional, but just do chest compressions. So let's talk about chest compressions.

Chuck Bryant: Well, before we do the chest compressions. If I came in here, luckily we have a nice flat first grade carpet type of scene in here. So I would not have to move you, but I do want to get you on your back on a flat hard surface. If you are face down, then that's sad for you and I would gently roll you actually I'd probably do it like quicker.

Josh Clark: Well, you want to really be careful to support the neck because if somebody already has a neck injury, you could make it way worse if you just flop them around.

Chuck Bryant: Or if they have a piece of steak stuck in their throat. You don't want to get it lodged further.

Josh Clark: So you want to support the head and neck as you pull the person toward you so that they're on their back now.

Chuck Bryant: Right. Since 2010, it used to be the ABC method: Airway, Breathing, and Circulation. They've now revised that to the CAB method.

Josh Clark: Yeah, and airway meant that you would stick your finger down the person's throat to see if there was anything you could dislodge if they passed out from choking. Now it's just basically chest compressions and the AB -

Chuck Bryant: Comes second and third.

Josh Clark: Like scraping out the airway and breathing, rescue breathing. You don't even do those if you don't know what you're doing. It's all chest compression.

Chuck Bryant: That's right, but the new order once again just remember think CAB. I've got to call a cab.

Josh Clark: But don't call a cab. That would just waste time. They won't know what you're talking about.

Chuck Bryant: That's right. So with chest compressions, we've talked a lot about it. What you want to do is you want to kneel near the neck and shoulders. You've probably seen this on TV. It's pretty accurate, usually. Put the heel of your hands on top of one another in the center of the chest midway between the nipples.

Josh Clark: So one palm down. The heel of your hand in the middle of the chest with your other hand over it. You're just forming this really solid piece of hand.

Chuck Bryant: That's right. You want to keep your elbows straight like they do on TV, so you're not using all of your arms. You're actually using your body weight to compress the chest I think - how many inches? One to two inches for an adult.

Josh Clark: You want to compress it down one to two inches. That's got to seem like a lot.

Chuck Bryant: What if you're the person on the ground?

Josh Clark: No, if like you're making the compressions like pushing somebody's chest in two inches. That's significant, you know?

Chuck Bryant: That's why you've got to put all of your body into it. Keep those arms and elbows locked and nice and rigid.

Josh Clark: Oh, and if you're in Canada or the UK, you want to compress someone's chest 2.54 centimeters to 5.08 centimeters. That's what we're saying when we say one to two inches.

Chuck Bryant: In this case, it's much easier to learn inches.

Josh Clark: So you want to make these chest compressions about 100 times a minute. We have a base 60 second minute, so 100 seems weird to us, right? How do you keep that rhythm in your head?

Chuck Bryant: It sounds unbelievable, but you want to hum the song in your head "Staying Alive" by the Bee Gees.

Josh Clark: It actually has 103 beats a minute. So if you can hit that song Ah, ah, ah, ah, stayin' alive, stayin' alive, stayin' alive.

Chuck Bryant: Pump, pump, pump, pump. Stayin' alive. Pump, pump, pump. About that fast.

Josh Clark: Don't like hold that pump on the "alive". You want to keep it going. You're going to hit 100 to 103 chest compression a minute. It's so awesome that it's "Stayin' Alive".

Chuck Bryant: I know. They chose a great song because most people know that song. They say most people can remember the pace of that song and its right at the 100 to 103 beats per minute. So you're doing pretty well there.

Josh Clark: And if you have a baby on your hands, you want to do chest compressions using the same techniques, but you only want to compress the chest about one inch, I believe, one and a half inches and you're using your middle finger and your index finger rather than the heels of your hands; but you're still doing it in between the nipples one and a half inch compressions 100 a minute.

Chuck Bryant: Yeah, and just less aggressive.

Josh Clark: And you want to support the baby's head while you're doing it. So basically you want to lay them across like the length of your forearm with their head in your hand.

Chuck Bryant: I cannot imagine anything more horrifying than performing CPR on a baby, but it's good to know. What you're doing here is you are basically squeezing the heart between the breastbone and the backbone to artificially get blood out of it moving through the body; that oxygenated blood. Like are you literally trying to get the heart going again or just deliver oxygen until someone gets there?

Josh Clark: No, the defibrillation is what gets the heart going. All you're doing is distributing oxygenated blood through the body. Like when the heart pumps, it doesn't make a whole circuit through your body. It just pumps the blood a little bit, a little bit, and a little bit. Eventually, this little segment of blood with each pump will follow the course through the body. So you are oxygenating, you're pumping oxygenated blood through the body.

Chuck Bryant: And you can go to is a good website to reinforce this, but again American Red Cross is where you want to go to get the regular class and get certified.

Josh Clark: Right, and they will teach you also rescue breathing too. Because I guess you're then oxygenating the blood or you are allowing the blood to be oxygenated by introducing air into the lungs. So, yeah, all you're doing is keeping like the body probably like specifically the brain fed with blood through CPR. That's what you're doing. So why wouldn't somebody want to do this?

Chuck Bryant: Well, one of the first things I looked up was lawsuits because I never knew if it was true or not, but you always hear people like I don't want to get sued. I don't want to perform CPR on that person. There's something called Good Samaritan Laws. You've heard of these?

Josh Clark: Uh, huh. Remember the last episode of Seinfeld. They all got evicted on the Good Samaritan Law.

Chuck Bryant: Yeah, there's various incarnations of the Good Samaritan Laws, but in the case of CPR it protects people that perform CPR generally if they are medically trained.

Josh Clark: Oh, so like if you have a CPR certification, you'd be protected?

Chuck Bryant: You'd be protected and it must be like if you tried to save me; it's got to be your idea like hey, I'm just going to go save this guy. And someone didn't drag you over there and say he's a doctor. You can be a doctor and still be protected like in the hospital. Like it doesn't cover hospitals and stuff.

Josh Clark: Yeah, because that's their job. They're not just being a Good Samaritan.

Chuck Bryant: It's got to be entirely voluntary and certain states - this is a state thing obviously - certain states are now enacting laws that protect anyone. I know Pennsylvania passed one last year that even if you're not certified and you give it the old college try, then you can't be sued which is great. You want people diving in there.

Josh Clark: Can you imagine if like you saved my life, but I didn't ask you to. So I'm suing you.

Chuck Bryant: Yeah. Also into the freakonomics site because you know how they always break things down into interesting ways like racially and as far as like income goes. Out of 14,225 cardiac arrest patients, a bystander initiated CPR was provided 28.6 percent of the time.

Josh Clark: Wow! That's it?

Chuck Bryant: Yeah. And in low income black neighborhoods, low income white neighborhoods, and low income integrated neighborhoods and high income black neighborhoods you're odds of getting CPR performed are way less than high income white neighborhoods and high income integrated neighborhoods.

Josh Clark: I wonder why.

Chuck Bryant: I don't know, but freakonomics is always studying all that stuff and how it affects the United States economically and racially. So I thought that was interesting.

Josh Clark: There's a lot of people also for a long time worried about catching any disease.

Chuck Bryant: Oh, from like mouth to mouth?

Josh Clark: Yeah, which is another reason apparently the Heart Association said let's just do chest compressions only. Like you're not going to catch anything, but supposedly there's no documented case of anyone catching anything serious from giving mouth to mouth rescue breathing. So nothing to worry about there either. Although, I think if you do that to a drowning victim and you're a drowning victim, they often spit up stuff so you might get a face full of seawater, but frankly that's a small price to pay.

Chuck Bryant: For being a hero. Have you ever seen this go down? Heimlich or CPR or anything?

Josh Clark: No, not in person.

Chuck Bryant: I haven't either. I can't imagine that would be and I have friend who have like seen stuff like this in like restaurants. I think I had one friend that some guy like drop dead on the beach and some guy brought him back to life.

Josh Clark: Neat.

Chuck Bryant: Yeah, I would love to be there. I'd love to do it.

Josh Clark: Well, we could start looking for situations.

Chuck Bryant: Would you jump in there?

Josh Clark: Oh yeah, I like to think I would. Sure.

Chuck Bryant: I would. I think if someone else was really confident ahead of me, I wouldn't like shove them aside.

Josh Clark: Step aside. I'm going to try my hand at this.

Chuck Bryant: But I would, sure, I would definitely get in there.

Josh Clark: Right on. Well, we should also say this. It probably accounts for one of the reasons why people don't do it is because they think they would and then it happens and they are frozen in panic or terror or whatever. So it's apparently one of the things this article says is that's another reason why people aren't thinking. You said it yourself, when you came into the podcast booth; you screamed. Luckily, you shook it off.

Chuck Bryant: I screamed for Jerry.

Josh Clark: I mean, yeah, you shook it off and like started to think, but you screamed. If you want to learn more about CPR, you can go to and type that word in the search bar. We strongly urge you instead or in addition to go to and look for a CPR course near you and you can take it. I said org, so it's time for listener mail.

Chuck Bryant: Yeah, Josh, this is perfect timing for this email. It just came in actually a couple of days ago. It is sad, but this guy wanted to get the message out. This is from Dan in Austin. Guys, been meaning to write for ages with little bits and pieces that I've picked up from working as a travel photographer in Indonesia for almost 20 years. However, events this past summer made these seem like trivialities taking this long to complete the email. In July of last year while playing with friends in the backyard, my 16 year old daughter suffered sudden cardiac arrest and collapsed.

Despite the best efforts of those around her, they were not able to recover her pulse and she passed on. We would never know the exact nature of the attack, but I've since discovered such attacks which could be from a number of causes that are alarmingly and tragically frequent in healthy young adults. Although broadly defined by either structural defects or faults within the electrical circuits that coordinate the heart's muscles, essential beats, and sudden cardiac arrests - which we have been talking about here - strikes down between 4,000 and 7,000 children every year in the U.S. alone.

Like we said, this guy's daughter was a totally healthy 16 year old. Unlike many of the diseases and conditions that you have covered on the show, with SCA the first symptoms of a life threatening condition may be at the time of death. Even equipped with resuscitation equipment, the survival rates are terrifyingly small. Without any equipment, they are almost nonexistent. There are tests, however, that can be done once a kid reaches a certain age, about 14 when the heart has reached its adult size.

But as individuals walking down the street, the cost of these tests may seem prohibitively expensive to parents who are not adequately informed of the hidden dangers that their children face. There are, however, incredible organizations out there that are working to change both the public awareness and the risks of SCA and are also conducting screening programs to get as many children as possible checked for no cost. So one of these coincidentally is in Austin where he lives.

He came out to our variety show, by the way. It's called the Championship Hearts Foundation. And that is and that's hearts plural. They have the expressed purpose of making cardiac screening affordable and accessible to as many families as possible and frequently conducts community screenings around Central Texas where they see 500 kids a day. When I can tell you that they can find the presence of some form of potentially fatal cardiac condition in 1 out of every 200 kids or less, you can appreciate the value of their mission. For all these kids and their families, this means the saving of a life. With proper diagnosis and treatment, many children identified go on to live healthy lives and active lives. So had I been better informed, guys, of this potentially fatal yet silent dangers that lurk unseen, I would have made sure to have my daughter scanned just as I will have my sons scanned when they are old enough.

I hope that every parent listening does the same. So that is Dan and that is and he said that there's lots of good organizations. I didn't know about that and if I ever have kids, that's something that I am going to have done when they reach the right age.

Josh Clark: Yeah. Maybe we should just start grabbing random kids off the street and having them screened.

Chuck Bryant: Have you been checked?

Josh Clark: No.

Chuck Bryant: I bet a lot of parents have no idea about this. It's very sad.

Josh Clark: Yeah, well, thank you very much, Dan for letting everybody know. That was a great letter.

Chuck Bryant: Yeah, we've corresponded a couple of times over the past few days. It's just unbelievable what he went through, a very good guy.

Josh Clark: Well, cool. Thank you for writing in. If you have a story that you think everybody needs to know about that no one does, we want to help you get the word out.

Chuck Bryant: Heck, yeah.

Josh Clark: You can tweet to us at syskpodcast. You can join us on Send us an email to and you can always find us on the web at

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Duration: 30 minutes