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The first time I stood in the operating room and watched a real surgery, I had no idea what to expect.
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I was a college student in engineering.
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I thought it was going to be like on TV,
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ominous music playing in the background, beads of sweat pouring down the surgeon’s face.
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But it wasn’t like that at all.
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There was music playing on this day. I think it was Madonna’s greatest hits.
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And there was plenty of conversation, not just about the patient’s heart rate,
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but about sports and weekend plans.
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And since then, the more surgeries I watched, the more I realized this is how it is.
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In some weird ways, it’s just another day at the office.
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But every so often, the music gets turned down,
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everyone stops talking, and stares at exactly the same thing.
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And that’s when you know that something absolutely critical and dangerous is happening.
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The first time I saw that I was watching a type of surgery called laparoscopic surgery.
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And for those who are unfamiliar, laparoscopic surgery, instead of the large open incision you might be used to with surgery,
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a laparoscopic surgery is where the surgeon creates these three or more small incisions in the patient.
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And then inserts these long, thin instruments and a camera,
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and actually does the procedure inside the patient.
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This is great because this is much less risk of infections, much less pain, shorter recovery time.
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But there is a trade-off,
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because these incisions are created with a long, pointed device, called the trocar.
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And the way the surgeon uses this device is that he takes it
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and he presses it into the abdomen until it punctures through.
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And now the reason why everyone in the operating room was staring at that device on that day
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was because he had to be absolutely careful not to plunge it through and puncture it into the organs and blood vessels below.
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But this problem should seem pretty familiar to all of you,
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because I’m pretty sure you’ve seen it somewhere else.
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Remember this?
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You knew that at any second, that straw was going to plunge through.
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And you didn’t know if it was going to go out the other side and straight into your hand,
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or if you were going to get juice everywhere,
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but you were terrified. Right?
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Every single time you did this, you experienced the same fundamental physics
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that I was watching in the operating room that day.
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And it turns out it really is a problem.
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In 2003, the FDA actually came out and said
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that trocar incisions might be the most dangerous step in minimally invasive surgery.
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Again in 2009, we see a paper that says that
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trocars account for over half of all major complications in laparoscopic surgery.
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And, oh by the way, this hasn’t changed for 25 years.
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So when I got to graduate school, this is what I wanted to work on.
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I was trying to explain to a friend of mine what exactly I was spending my time doing,
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and I said,
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“It’s like when you’re drilling through a wall to hang something in your apartment.
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There’s that moment when the drill first punctures through the wall
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and there’s this, plunge. Right?”
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And he looked at me and he said,
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“You mean like when they drill into people’s brains?”
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And I said, “Excuse me?”
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And then I looked it up and they do drill into people’s brains.
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A lot of neurosurgical procedures actually start with a drill incision through the skull.
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And if the surgeon isn’t careful, he can plunge directly into the brain.
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So this is the moment when I started thinking, okay,
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cranial drilling, laparoscopic surgery, why not other areas of medicine?
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Because think about it, when was the last time you went to the doctor and you didn’t get stuck with something? Right?
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So the truth is, in medicine puncture is everywhere.
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And here are just a couple of the procedures that I’ve found that involve some tissue puncture step.
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And if we take just three of them,
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laparoscopic surgery, epidurals and cranial drillings,
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these procedures account for over 30,000 complications every year in this country alone.
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I call that a problem worth solving.
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So let’s take a look at some of the devices that are used in these types of procedures.
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I’ve mentioned epidurals.
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This is an epidural needle.
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It’s used to puncture through the ligaments in the spine and deliver anesthesia during childbirth.
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Here’s a set of bone marrow biopsy tools.
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These are actually used to burrow into the bone and collect bone marrow or sample bone lesions.
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Here’s a bayonet from the Civil War.
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If I had told you it was a medical puncture device, you probably would have believed me.
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Right? Because what’s the difference?
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So the more I did this research, the more I thought there has to be a better way to do this.
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And for me, the key to this problem is that all these different puncture devices share a common set of fundamental physics.
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So what are those physics? Let’s go back to drilling through a wall.
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So you’re applying a force on the drill toward the wall. Right?
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And Newton says, the wall is going to apply force back, equal and opposite.
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So as you drill through the wall, those forces balance.
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But then there’s that moment when the drill first punctures through the other side of the wall,
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and right at that moment, the wall can’t push back anymore.
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But your brain hasn’t reacted to that change in force.
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So for that millisecond, or however long it takes you to react, you’re still pushing.
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and that unbalanced force causes an acceleration,
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and that is the plunge.
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But what if…what if right at the moment of puncture,
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you could pull that tip back, actually oppose the forward acceleration?
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That’s what I set out to do.
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So imagine you have a device and it’s got some kind of sharp tip to cut through tissue.
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What’s the simplest way you could pull that tip back?
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I chose a spring.
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So when you extend that spring, you extend that tip out so it’s ready to puncture tissue.
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The spring wants to pull the tip back.
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So how do you keep the tip in place until the moment of puncture?
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I used this mechanism.
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When the tip of the device is pressed against tissue,
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the mechanism expands outward and wedges in place against the wall.
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And the friction that’s generated locks it in place and prevents the spring from retracting the tip.
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But right at the moment of puncture, the tissue can’t push back on the tip anymore.
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So the mechanism unlocks and the spring retracts the tip.
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Let me show you that happening in slow motion. This is about 2,000 frames a second,
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and I’d like you to notice the tip that’s right there at the bottom, about to puncture through tissue.
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And you’ll see that right at the moment of puncture,
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right there, the mechanism unlocks and retracts that tip back.
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I want to show it to you again, a little closer up.
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So you’re going to see the sharp bladed tip,
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and right when it punctures that rubber membrane, it’s going to disappear into this white blunt sheath.
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Right there.
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That happens within four 100th of a second after puncture.
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And because this device is designed to address the physics of puncture
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and not the specifics of cranial drilling or laparoscopic surgery or another procedure,
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it’s applicable across these different medical disciplines and across different length scales.
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But it didn’t always look like this.
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This was my first prototype.
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Yes, those are popsicle sticks and there’s a rubber band at the top.
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It took about 30 minutes to do this, but it worked.
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And it proved to me that my idea worked and justified the next couple years of work on this project.
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I worked on this because this problem really fascinated me. It kept me up at night.
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But I think it should fascinate you too,
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because I said puncture is everywhere,
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that means at some point, it’s going to be your problem too.
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That first day in the operating room I never expected to find myself on the other end of a trocar.
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But last year, I got appendicitis when I was visiting Greece.
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So I was in the hospital in Athens, and the surgeon was telling me he was going to perform a laparoscopic surgery.
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He was going to remove my appendix through these tiny incisions.
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And he was talking about what I could expect for the recovery and what was going to happen.
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He said, “Do you have any questions?”
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And I said, “Just one doc. What kind of trocar do you use?”
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So my favourite quote about laparoscopic surgery comes from a doctor H. C. Jacobaeus.
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“It is puncture itself that causes risk.”
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And that’s my favorite quote because H. C. Jacobaeus was the first person to ever perform laparoscopic surgery on humans,
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and he wrote that in 1912.
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So this is a problem that’s been injuring and even killing people for over 100 years.
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So it’s easy to think that for every major problem out there, there’s some team of experts working around the clock to solve it.
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The truth is that’s not always the case.
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We have to be better at finding those problems and finding ways to solve them.
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So if you come across a problem that grabs you,
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let it keep you up at night.
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Allow yourself to be fascinated,
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because there are so many lives to save.
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Thank you.