1
00:00:00,879 --> 00:00:02,855
The first time I stood
in the operating room

2
00:00:02,855 --> 00:00:04,727
and watched a real surgery,

3
00:00:04,727 --> 00:00:07,302
I had no idea what to expect.

4
00:00:07,302 --> 00:00:09,277
I was a college student in engineering.

5
00:00:09,277 --> 00:00:11,477
I thought it was going to be like on TV.

6
00:00:11,477 --> 00:00:13,382
Ominous music playing in the background,

7
00:00:13,382 --> 00:00:16,381
beads of sweat pouring down the surgeon's face.

8
00:00:16,381 --> 00:00:18,541
But it wasn't like that at all.

9
00:00:18,541 --> 00:00:20,140
There was music playing on this day,

10
00:00:20,140 --> 00:00:22,862
I think it was Madonna's greatest hits. (Laughter)

11
00:00:22,862 --> 00:00:24,989
And there was plenty of conversation,

12
00:00:24,989 --> 00:00:26,989
not just about the patient's heart rate,

13
00:00:26,989 --> 00:00:29,762
but about sports and weekend plans.

14
00:00:29,762 --> 00:00:31,698
And since then, the more surgeries I watched,

15
00:00:31,698 --> 00:00:33,525
the more I realized this is how it is.

16
00:00:33,525 --> 00:00:36,278
In some weird way, it's just
another day at the office.

17
00:00:36,278 --> 00:00:38,183
But every so often

18
00:00:38,183 --> 00:00:40,281
the music gets turned down,

19
00:00:40,281 --> 00:00:41,711
everyone stops talking,

20
00:00:41,711 --> 00:00:44,695
and stares at exactly the same thing.

21
00:00:44,695 --> 00:00:46,855
And that's when you know
that something absolutely critical

22
00:00:46,855 --> 00:00:49,295
and dangerous is happening.

23
00:00:49,295 --> 00:00:50,311
The first time I saw that

24
00:00:50,311 --> 00:00:51,543
I was watching a type of surgery

25
00:00:51,543 --> 00:00:53,832
called laparoscopic surgery

26
00:00:53,832 --> 00:00:56,390
And for those of you who are unfamiliar,

27
00:00:56,390 --> 00:00:58,783
laparoscopic surgery, instead of the large

28
00:00:58,783 --> 00:01:01,277
open incision you might
be used to with surgery,

29
00:01:01,277 --> 00:01:03,485
a laparoscopic surgery
is where the surgeon creates

30
00:01:03,485 --> 00:01:06,502
these three or more small
incisions in the patient.

31
00:01:06,502 --> 00:01:09,368
And then inserts these long, thin instruments

32
00:01:09,368 --> 00:01:10,482
and a camera,

33
00:01:10,482 --> 00:01:14,333
and actually does the procedure inside the patient.

34
00:01:14,333 --> 00:01:16,925
This is great because there's
much less risk of infection,

35
00:01:16,925 --> 00:01:20,085
much less pain, shorter recovery time.

36
00:01:20,085 --> 00:01:22,677
But there is a trade-off,

37
00:01:22,677 --> 00:01:24,461
because these incisions are created

38
00:01:24,461 --> 00:01:26,959
with a long, pointed device

39
00:01:26,959 --> 00:01:28,423
called a trocar.

40
00:01:28,423 --> 00:01:30,617
And the way the surgeon uses this device

41
00:01:30,617 --> 00:01:32,033
is that he takes it

42
00:01:32,033 --> 00:01:34,000
and he presses it into the abdomen

43
00:01:34,000 --> 00:01:37,255
until it punctures through.

44
00:01:37,255 --> 00:01:40,327
And now the reason why 
everyone in the operating room

45
00:01:40,327 --> 00:01:42,974
was staring at that device on that day

46
00:01:42,974 --> 00:01:46,205
was because he had to be absolutely careful

47
00:01:46,205 --> 00:01:47,672
not to plunge it through

48
00:01:47,672 --> 00:01:51,613
and puncture it into the organs 
and blood vessels below.

49
00:01:51,613 --> 00:01:53,452
But this problem should seem 
pretty familiar to all of you

50
00:01:53,452 --> 00:01:56,373
because I'm pretty sure 
you've seen it somewhere else.

51
00:01:56,373 --> 00:01:58,165
(Laughter)

52
00:01:58,165 --> 00:01:59,821
Remember this?

53
00:01:59,821 --> 00:02:03,937
(Applause)

54
00:02:03,937 --> 00:02:05,813
You knew that at any second

55
00:02:05,813 --> 00:02:07,693
that straw was going to plunge through,

56
00:02:07,693 --> 00:02:09,278
and you didn't know if it was 
going to go out the other side

57
00:02:09,278 --> 00:02:10,581
and straight into your hand,

58
00:02:10,581 --> 00:02:12,277
or if you were going to
get juice everywhere,

59
00:02:12,277 --> 00:02:15,580
but you were terrified. Right?

60
00:02:15,580 --> 00:02:17,556
Every single time you did this,

61
00:02:17,556 --> 00:02:20,112
you experienced the same
fundamental physics

62
00:02:20,112 --> 00:02:23,192
that I was watching in the operating room that day.

63
00:02:23,192 --> 00:02:25,738
And it turns out it really is a problem.

64
00:02:25,738 --> 00:02:28,530
In 2003, the FDA actually came out and said

65
00:02:28,530 --> 00:02:31,907
that trocar incisions might 
be the most dangerous step

66
00:02:31,907 --> 00:02:33,923
in minimally invasive surgery.

67
00:02:33,923 --> 00:02:36,363
Again in 2009, we see a paper that says

68
00:02:36,363 --> 00:02:38,547
that trocars account for over half

69
00:02:38,547 --> 00:02:42,234
of all major complications in laparoscopic surgery.

70
00:02:42,234 --> 00:02:43,376
And, oh by the way,

71
00:02:43,376 --> 00:02:46,970
this hasn't changed for 25 years.

72
00:02:46,970 --> 00:02:48,500
So when I got to graduate school,

73
00:02:48,500 --> 00:02:50,368
this is what I wanted to work on.

74
00:02:50,368 --> 00:02:52,176
I was trying to explain to a friend of mine

75
00:02:52,176 --> 00:02:54,291
what exactly I was spending my time doing,

76
00:02:54,291 --> 00:02:56,107
and I said,

77
00:02:56,107 --> 00:02:58,283
"It's like when you're drilling through a wall

78
00:02:58,283 --> 00:03:01,483
to hang something in your apartment.

79
00:03:01,483 --> 00:03:05,395
There's that moment when the drill
first punctures through the wall

80
00:03:05,395 --> 00:03:09,047
and there's this plunge. Right?

81
00:03:11,389 --> 00:03:13,430
And he looked at me and he said,

82
00:03:13,430 --> 00:03:16,901
"You mean like when they drill 
into people's brains?"

83
00:03:16,901 --> 00:03:19,233
And I said, "Excuse me?" (Laughter)

84
00:03:19,233 --> 00:03:22,281
And then I looked it up and they
do drill into people's brains.

85
00:03:22,281 --> 00:03:24,345
A lot of neurosurgical procedures

86
00:03:24,345 --> 00:03:28,127
actually start with a drill
incision through the skull.

87
00:03:28,127 --> 00:03:29,912
And if the surgeon isn't careful,

88
00:03:29,912 --> 00:03:33,496
he can plunge directly into the brain.

89
00:03:33,496 --> 00:03:35,662
So this is the moment when I started thinking,

90
00:03:35,662 --> 00:03:38,970
okay, cranial drilling, laparoscopic surgery,

91
00:03:38,970 --> 00:03:40,634
why not other areas of medicine?

92
00:03:40,634 --> 00:03:42,578
Because think about it, when was
the last time you went to the doctor

93
00:03:42,578 --> 00:03:45,325
and you didn't get stuck with something? Right?

94
00:03:45,325 --> 00:03:46,642
So the truth is

95
00:03:46,642 --> 00:03:49,194
in medicine puncture is everywhere.

96
00:03:49,194 --> 00:03:51,986
And here are just a couple
of the procedures that I've found

97
00:03:51,986 --> 00:03:55,195
that involve some tissue puncture step.

98
00:03:55,195 --> 00:03:57,274
And if we take just three of them —

99
00:03:57,274 --> 00:04:01,370
laparoscopic surgery, 
epidurals, and cranial drilling —

100
00:04:01,370 --> 00:04:05,349
these procedures account 
for over 30,000 complications

101
00:04:05,349 --> 00:04:08,200
every year in this country alone.

102
00:04:08,200 --> 00:04:10,915
I call that a problem worth solving.

103
00:04:10,915 --> 00:04:13,240
So let's take a look at some of the devices

104
00:04:13,240 --> 00:04:15,744
that are used in these types of procedures.

105
00:04:15,744 --> 00:04:18,969
I mentioned epidurals. This is an epidural needle.

106
00:04:18,969 --> 00:04:21,286
It's used to puncture through 
the ligaments in the spine

107
00:04:21,286 --> 00:04:23,725
and deliver anesthesia during childbirth.

108
00:04:23,725 --> 00:04:26,278
Here's a set of bone marrow biopsy tools.

109
00:04:26,278 --> 00:04:28,214
These are actually used
to burrow into the bone

110
00:04:28,214 --> 00:04:31,714
and collect bone marrow
or sample bone lesions.

111
00:04:31,714 --> 00:04:33,624
Here's a bayonette from the Civil War.

112
00:04:33,624 --> 00:04:36,640
(Laughter)

113
00:04:36,640 --> 00:04:39,233
If I had told you it was a 
medical puncture device

114
00:04:39,233 --> 00:04:41,449
you probably would have believed me.

115
00:04:41,449 --> 00:04:43,642
Because what's the difference?

116
00:04:43,642 --> 00:04:45,577
So, the more I did this research

117
00:04:45,577 --> 00:04:47,161
the more I thought there has to be

118
00:04:47,161 --> 00:04:49,190
a better way to do this.

119
00:04:49,190 --> 00:04:51,609
And for me the key to this problem

120
00:04:51,609 --> 00:04:54,020
is that all these different puncture devices

121
00:04:54,020 --> 00:04:57,822
share a common set of fundamental physics.

122
00:04:57,822 --> 00:04:59,374
So what are those physics?

123
00:04:59,374 --> 00:05:00,966
Let's go back to drilling through a wall.

124
00:05:00,966 --> 00:05:04,598
So you're applying a force 
on a drill towards the wall.

125
00:05:04,598 --> 00:05:07,942
And Newton says the wall
is going to apply force back,

126
00:05:07,942 --> 00:05:09,207
equal and opposite.

127
00:05:09,207 --> 00:05:11,170
So, as you drill through the wall,

128
00:05:11,170 --> 00:05:13,100
those forces balance.

129
00:05:13,100 --> 00:05:14,641
But then there's that moment

130
00:05:14,641 --> 00:05:16,777
when the drill first punctures
through the other side of the wall,

131
00:05:16,777 --> 00:05:19,633
and right at that moment 
the wall can't push back anymore.

132
00:05:19,633 --> 00:05:23,100
But your brain hasn't reacted 
to that change in force.

133
00:05:23,100 --> 00:05:24,161
So for that millisecond,

134
00:05:24,161 --> 00:05:26,793
or however long it takes you 
to react, you're still pushing,

135
00:05:26,793 --> 00:05:29,337
and that unbalanced force 
causes an acceleration,

136
00:05:29,337 --> 00:05:32,449
and that is the plunge.

137
00:05:32,449 --> 00:05:36,353
But what if right at the moment of puncture

138
00:05:36,353 --> 00:05:37,977
you could pull that tip back,

139
00:05:37,977 --> 00:05:40,990
actually oppose the forward acceleration?

140
00:05:40,990 --> 00:05:43,127
That's what I set out to do.

141
00:05:43,127 --> 00:05:44,447
So imagine you have a device

142
00:05:44,447 --> 00:05:47,647
and it's got some kind of sharp tip 
to cut through tissue.

143
00:05:47,647 --> 00:05:50,860
What's the simplest way 
you could pull that tip back?

144
00:05:50,860 --> 00:05:52,671
I chose a spring.

145
00:05:52,671 --> 00:05:55,255
So when you extend that spring, 
you extend that tip out

146
00:05:55,255 --> 00:05:57,470
so it's ready to puncture tissue,

147
00:05:57,470 --> 00:05:58,910
the spring wants to pull the tip back.

148
00:05:58,910 --> 00:06:00,663
How do you keep the tip in place

149
00:06:00,663 --> 00:06:03,127
until the moment of puncture?

150
00:06:03,127 --> 00:06:05,550
I used this mechanism.

151
00:06:05,550 --> 00:06:08,111
When the tip of the device
is pressed against tissue,

152
00:06:08,111 --> 00:06:11,951
the mechanism expands outwards 
and wedges in place against the wall.

153
00:06:11,951 --> 00:06:13,655
And the friction that's generated

154
00:06:13,655 --> 00:06:16,847
locks it in place and prevents
the spring from retracting the tip.

155
00:06:16,847 --> 00:06:18,734
But right at the moment of puncture,

156
00:06:18,734 --> 00:06:20,798
the tissue can't push back
on the tip anymore.

157
00:06:20,798 --> 00:06:23,980
So the mechanism unlocks 
and the spring retracts the tip.

158
00:06:23,980 --> 00:06:25,630
Let me show you that 
happening in slow motion.

159
00:06:25,630 --> 00:06:27,278
This is about 2,000 frames a second,

160
00:06:27,278 --> 00:06:29,150
and I'd like you to notice the tip

161
00:06:29,150 --> 00:06:31,778
that's right there on the bottom, 
about to puncture through tissue.

162
00:06:31,778 --> 00:06:34,839
And you'll see that 
right at the moment of puncture,

163
00:06:36,590 --> 00:06:39,892
right there, the mechanism unlocks 
and retracts that tip back.

164
00:06:39,892 --> 00:06:42,236
I want to show it to you again, a little closer up.

165
00:06:42,236 --> 00:06:44,428
You're going to see the sharp bladed tip,

166
00:06:44,428 --> 00:06:46,420
and right when it punctures 
that rubber membrane

167
00:06:46,420 --> 00:06:50,572
it's going to disappear
into this white blunt sheath.

168
00:06:50,572 --> 00:06:52,437
Right there.

169
00:06:52,437 --> 00:06:57,101
That happens within four 100ths 
of a second after puncture.

170
00:06:57,101 --> 00:07:00,901
And because this device is designed
to address the physics of puncture

171
00:07:00,901 --> 00:07:02,733
and not the specifics of cranial drilling

172
00:07:02,733 --> 00:07:04,940
or laparoscopic surgery, 
or another procedure,

173
00:07:04,940 --> 00:07:07,597
it's applicable across these
different medical disciplines

174
00:07:07,597 --> 00:07:10,628
and across different length scales.

175
00:07:10,628 --> 00:07:12,741
But it didn't always look like this.

176
00:07:12,741 --> 00:07:14,926
This was my first prototype.

177
00:07:14,926 --> 00:07:17,568
Yes, those are popsicle sticks,

178
00:07:17,568 --> 00:07:19,470
and there's a rubber band at the top.

179
00:07:19,470 --> 00:07:22,870
It took about 30 minutes to do this, but it worked.

180
00:07:22,870 --> 00:07:24,566
And it proved to me that my idea worked

181
00:07:24,566 --> 00:07:27,958
and it justified the next couple
years of work on this project.

182
00:07:27,958 --> 00:07:29,766
I worked on this because

183
00:07:29,766 --> 00:07:31,429
this problem really fascinated me.

184
00:07:31,429 --> 00:07:33,558
It kept me up at night.

185
00:07:33,558 --> 00:07:36,540
But I think it should fascinate you too,

186
00:07:36,540 --> 00:07:38,442
because I said puncture is everywhere.

187
00:07:38,442 --> 00:07:42,706
That means at some point 
it's going to be your problem too.

188
00:07:42,706 --> 00:07:44,266
That first day in the operating room

189
00:07:44,266 --> 00:07:47,250
I never expected to find myself 
on the other end of a trocar.

190
00:07:47,250 --> 00:07:51,140
But last year, I got appendicitis 
when I was visiting Greece.

191
00:07:51,140 --> 00:07:52,970
So I was in the hospital in Athens,

192
00:07:52,970 --> 00:07:54,458
and the surgeon was telling me

193
00:07:54,458 --> 00:07:56,594
he was going to perform 
a laparoscopic surgery.

194
00:07:56,594 --> 00:07:59,346
He was going to remove my appendix 
through these tiny incisions,

195
00:07:59,346 --> 00:08:02,040
and he was talking about what
I could expect for the recovery,

196
00:08:02,040 --> 00:08:03,482
and what was going to happen.

197
00:08:03,482 --> 00:08:05,900
He said, "Do you have any questions?"
And I said, "Just one, doc.

198
00:08:05,900 --> 00:08:09,374
What kind of trocar do you use?"

199
00:08:09,374 --> 00:08:12,879
So my favorite quote 
about laparoscopic surgery

200
00:08:12,879 --> 00:08:15,525
comes from a Doctor H. C. Jacobaeus:

201
00:08:15,525 --> 00:08:19,189
"It is puncture itself that causes risk."

202
00:08:19,189 --> 00:08:22,325
That's my favorite quote 
because H.C. Jacobaeus

203
00:08:22,325 --> 00:08:26,365
was the first person to ever perform 
laparoscopic surgery on humans,

204
00:08:26,365 --> 00:08:29,797
and he wrote that in 1912.

205
00:08:29,797 --> 00:08:35,581
This is a problem that's been injuring and
even killing people for over 100 years.

206
00:08:35,581 --> 00:08:37,815
So it's easy to think that for
every major problem out there

207
00:08:37,815 --> 00:08:41,751
there's some team of experts 
working around the clock to solve it.

208
00:08:41,751 --> 00:08:45,100
The truth is that's not always the case.

209
00:08:45,100 --> 00:08:47,545
We have to be better at finding those problems

210
00:08:47,545 --> 00:08:50,313
and finding ways to solve them.

211
00:08:50,313 --> 00:08:53,569
So if you come across a problem that grabs you,

212
00:08:53,569 --> 00:08:55,450
let it keep you up at night.

213
00:08:55,450 --> 00:08:57,593
Allow yourself to be fascinated,

214
00:08:57,593 --> 00:09:00,505
because there are so many lives to save.

215
00:09:00,505 --> 00:09:03,904
(Applause)