Surgeon Explains How to Tie Surgical Knots
Released on 11/27/2019
Oh, you're shaking.
What's wrong with you?
I'm nervous!
Oh my god.
I'm Annie Onishi.
Annie is a trauma surgeon.
She's explained operating rooms
and surgical procedures in technique critique.
As I tell my medical students,
vitals are vital.
We always talk about them,
we always wanna know what they are,
and yes, we ask what they are on the regular.
And I'm Peter Rubin.
Peter is a Wired contributor who covers
culture and technology.
Annie is going to teach Peter
how to suture and tie surgical knots
using different materials ranging
from easy to difficult.
[light music]
Hey Peter, you wanna know
about surgical knot tying
and suturing technique?
'Bout time I cross it off my bucket list.
Let's get you to some scrubs.
Excellent.
[light music]
The first thing we'll learn today
is surgical knot tying.
How much does this have in common
with tying a friendship bracelet?
This is 100%, the same activity
as tying a friendship bracelet.
Oh my god, I'm gonna get the marshmallows.
Let's do this.
So typically, medical students
will learn this during the first few days
of their surgery rotations,
and it's an activity that's mastered
over hours and hours of practice.
So, there's actually two types of knots.
There's the two handed knot,
and the one handed knot.
Today, I'm gonna be teaching you
the one handed knot.
Is that 'cause it's easier?
Turns out it's not easier,
it's just more applicable in general practice.
This is a know that we tie everywhere,
whether it be, we're fixing
the inferior vena cava during a major trauma case,
you're sewing little arteries on the heart,
or even things as simple as you're closing
skin of a little laceration in the emergency room.
It's all the same knot.
[light music]
So Peter, to help you learn knot tying,
today I brought you the surgery
resident starter pack.
So, is this like an official training tool?
Is that what people are gonna start using
in med school?
This is pretty darn official.
When students are first learning how to tie knots,
they use multicolor, large bore yarn
just like this.
The reason the color's helpful,
it will show you that you knot
is lying perfectly as you tie it.
And a one handed tie, there's actually
two knots, there's a forehand throw
and a back hand throw.
Okay.
All right, so what I'm gonna do,
I'm gonna take the white string
and hold it in my left hand
so that my purple is crossed.
See that?
Um hm.
Okay.
My forehand throw has an overhand grip like this
like you're riding the pony.
Okay, okay.
Can you ride the pony a little bit?
Ridin' the pony.
Ridin' the pony.
So, with your strings crossed,
you're gonna create a four shape.
Do you see the four?
I do.
Now, your index finger is gonna go
through the four and loop this tail
and bring it through the four.
Loop that tail and bring it through the four.
Just like that.
Just like that.
The whole thing?
Bring the whole tail through.
Whole tail through.
Now, with your right hand and your left hand
you're gonna put the knot down
and it should be nice and square.
That's excellent Peter.
Good.
I'm a doctor!
You're a doctor.
So, that's your forehand throw.
Okay.
Now for your backhand throw,
left hand comes back to neutral position
with the right string.
Adjust your grip on the purple string
to a karate chop grip.
Okay.
Now, use your middle finger
to get the tail through the four.
What?
Maintaining tension Maintaining tension.
on that white tail.
And bring it through.
Bring it through.
Oh through like that! Yes.
Now, you need to cross your hands.
Okay.
So, let's try it again.
Okay.
And then you alternate, forehand, backhand.
Okay.
Where are you likely to use
this sort of knot chain?
So, this is a knot that we tie everywhere,
whether it be we're fixing the inferior vena cava
during a major trauma case,
you're sewing little arteries on the heart,
or even things as simple as you're closing skin
of a little laceration in the emergency room.
It's all the same knot.
It's just a matter of what you're tying,
what kind of suture [crosstalk].
So, you are doing this as a chain.
Now depending on the suture material you're using,
the most knots you would ever tie
is like eight or 10.
Okay, now here's the problem.
Stop, freeze.
Here's the difference between me and you.
Look where your purple string is
versus where my purple string is.
Oh, you got it around the whole hand [crosstalk].
And that's gonna give you a little bit
of tension to make this guy easier.
Oh, but I still got ham hands.
You can do it.
You can do it.
These can't be ham hands.
Check this out [crosstalk].
Oh my god, I'm gonna hire you.
Just like the name of the knot.
Great.
I look at yours and I see friendship.
Friendship.
And here I see ranker and years of bitterness.
Indeed.
So, I have a feeling that the answer
to this is going to be everything.
But, what am I doing wrong?
I think the problem is coming
as the knot is going down.
You're not applying even tension,
so your knots are ending up stacked
instead of square.
When we teach the medical students
how to do this, they're just doing it constantly.
You find little strings tied to everything.
The mouse, the computer, their pants.
Oh, yeah, you really don't have to do much
when you cross back over to the forehand do you?
Yeah, you got it down.
Now what happens when the ends
start getting short?
Then you're done.
And I'm done.
Right.
Oh.
This is good to learn the mechanics
of the knots.
Okay.
This doesn't sit like real suture.
So, why don't we move on
to something more difficult.
I actually brought some suture material
to show you.
Okay.
[light music]
So, the way that suture is labeled
is zero is sort of the middle set point.
And something like a six-O is tiny, tiny.
That means six zeros all in a row.
The easiest thing to tie is O silk.
And is six-O the thinnest you can use?
Absolutely not.
It goes all the way down to like 10-O.
But that's used on very fine things
like a vein or an artery or a nerve.
So, for you, Peter, we're gonna use
sort of the elementary school, O-silk.
This is the same exact thing as your yarn,
but what's gonna make this a little harder
is that your suture's finer.
So, you're gonna have to work harder
to keep good tension and to make it sit nice.
So, again, the mechanics are the same.
It's really important that you, sort of,
follow the knot down with your finger
to get the knot to sit exactly where
you want it to sit.
All right Peter, so let's see.
So, I had this forehand throw.
You see that?
Good.
Jargon.
And use your, there you go.
Yes, you see how your, that was very instinctive.
What you did, your hand sort of,
crawled up the suture.
That's perfect.
Now, karate chop.
Good.
I called it, now in my brain,
this is ham hands because I have ham hands.
No, you have beautiful hands.
You have healing hands.
Don't, don't, don't do that.
So, Peter, I actually think you're ready
for the next curve ball.
Oh boy.
Which is, let's get you to do this
with gloves on.
So, there's no, like, in-between.
It's going from the training wheels.
Hell yeah, man.
To the grand prix.
Okay.
So, do doctors actually do the thing
where they're like [glove snapping],
Yeah, let's do this.
Oh, 100%, every time.
Okay, let's do this then.
Okay, so let's get started.
So, Peter, this is just gonna be the same thing.
Same knots.
But I just want you to get a sense
for how it feels different when you can't
actually feel the suture material
directly on your skin.
It's almost like numbness.
Wow, hey, guess what?
I'm even more terrible.
I didn't think this was possible.
Hmm.
Hmm.
That's not a sound you like to hear.
It's just interesting.
A million different people tie it.
That's the other thing you like to hear.
Well they just.
Hmm, that's interesting.
Every different person makes
their own unique mistake when they're
learning how to do this.
This is, your euphemisms are the best.
Keep going, you're doing great.
Okay.
What do you got there?
In real life your hands are wet.
Oh, hey, okay.
So, this is what like the bodily fluid?
Of your choosing.
Of my choosing?
And so actually, silk,
because it's a braided suture,
doesn't make too much of a difference.
Yes, I thought it would be a lot worse.
But if I give you a monofilament,
which is like a plastic one strand,
that will be harder with your hands wet.
But you're doing really good.
Yay!
You've really, I think, mastered the mechanics
of the knot tying.
You would just need some polishing
in terms of your tension, your knot placement.
So, what's gonna be next here.
What are we gonna do?
So, I have just the thing.
Have these creepy skin models
with a bunch of different types of incisions.
What?
Yep!
[light music]
It's solid and it's kinda a little giving
but it's dense.
It feels kinda real.
So, I have for you [crosstalk] here
a suture kit, and a four-O biosesyn
on a cutting needle.
And a cutting needle's what we use
to close skin with.
This is an absorbable monofilament.
Okay.
Four-O, so that's a little smaller
than what you've been working with.
So, the first thing you have here
is a needle driver.
And every surgical instrument locks in place.
So, practice that mechanism.
And then, real surgeons don't put their thumb
in that hole.
Push it with the but of your hand
and then close it.
And then you also need these pickups.
These are rough approximations
of Adson forceps with teeth.
So, these have teeth on the end of it
that help you grip skin.
These aren't tweezers.
These are not tweezers.
These are not tweezers.
These are called pickups.
Pickups.
And then that's the needle in there.
Okay.
So, be careful.
And you're gonna.
Oh, you put your thumb in the hole.
Just for that part.
Oh, hypocrisy.
Good.
Take the whole thing out?
Yep.
Oh, wait.
Wait.
Wait.
Wait.
Wait.
Wait.
Wait.
Wait.
Okay.
Okay.
Okay, so now, the way to properly hold the needle,
use your pickups to help you.
So, I'm gonna hold my needle
halfway back at a 45 degree angle here
and at the very tips of my needle driver.
All right, so now we're ready to close skin.
So, what I'm gonna teach you now,
is called the running subcuticular closure.
Okay.
Say it with me.
Running subcuticular closure Running subcuticular closure
Okay, and this is a nice way
to make the skin come together
and there's no stitches visible.
Okay.
So, I'm gonna pick up the edge of the
quote unqoute, skin.
Okay.
Take one bite sort of right in the apex
of this skin.
Is bite also a technical term?
It is.
I'm gonna then what's called
protect my needle.
Okay.
So, now, the sharp in the needle
is protected against this pickup.
Oh, okay.
And I'm just gonna do a couple
of one handed ties.
Usually three or four for this.
I'm alternating.
And then, when you get to the end,
I'll show you what to do.
You wanna try?
No.
But, I guess I have to.
I wanna keep it.
Yeah.
Exposed like there?
Sure, yeah.
Sure, there we go.
Good.
Back to the failure euphemisms.
Now, release your needle driver.
Oh.
I don't know.
Exactly, push it from behind.
'Cause you don't usually wanna
touch the tip of this needle
'cause you don't wanna either break it
or make it dull.
So, what you're gonna do is protect your needle.
That's it, perfect.
Pull through.
Good, and now you're ready to tie.
Do four single handed throws like you learned.
Okay.
Okay, now the color of the skin,
Right.
and the color of the filament,
Yeah.
there is not a lot of contrast
goin' on here.
Can I cheat with this?
No.
Here, I'm just gonna help you.
'Cause the point of this exercise
is to sew, not to tie.
Oh yeah!
You're doing so good.
I'm so proud of you.
I'm doing good.
All right, so, we're gonna pretend
that I did that.
Right.
And now it's anchored.
Yep.
So, then a running subcuticular closure,
if you use your imagination, is gonna end up
like a series of C's in the plane of the skin.
So, then your next bite, you're gonna evert
the opposite side of the skin.
You're gonna enter the tissue, sort of,
exactly opposite to where you came out.
And again, you're just gonna kinda run along
the dimension of the skin just like so.
You're gonna use the back of the needle
to push it along.
And if you're super slick, you'll load
your needle while it's held down
there for ya.
Hmm, and so the only knots
are really to anchor it at the beginning?
Exactly.
Oh look at that [crosstalk].
So, you're gonna pick up on this side.
But, I did it that way.
That's okay.
So, turn your body.
So, yep, that's it.
So, when you're the operating surgeon
you can hip check people,
you have to get yourself comfortable.
Out of my way!
There's a patient on the table.
Okay, so you're actually gonna
come along this dimension.
Okay.
Yeah.
Like so.
Again, use your pickups to put the tissue
where you want it to go.
I get to put the tissue where
I want it to go.
Yeah.
I am stuck.
But that's enough to get it out, I hope.
Yeah.
And, you know, in real subcuticular tissue
you wanna come out inside the wound
so that the stitch gets hidden Oh!
but that's okay.
For our purposes, that's your first bite.
That's fine.
The point of this closure is that
you don't see any suture.
So, am I going across or am I going along?
No, now you're going across.
Now, I'm going across.
But, again, use your pickups
to show yourself where you wanna go.
So, move along, make more progress.
Which means take a bite with your pickups
closer to your body.
Good.
Like so.
And I come across here?
Right, but this is in this dimension.
Oh right.
Right.
And now with this hand push the tissue.
Where are you?
There you go.
That's perfect.
Great.
Yeah. Let go.
All right, video's over.
[laughing]
Let go.
Pull this out.
Oh, hey it closed.
Look it's closing.
I know.
All right, now I need [crosstalk].
But at this rate, it's gonna heal
before you even finish.
Yeah, yeah, yeah.
Even if they don't look perfect,
these tend to heal up okay.
But, you can make this look like
nothing ever happened.
Which is kinda the.
Which is not what's happening
to your patient.
Oh, well, they're gonna have
a nice memento of their time with me.
That's right.
All right, so let's assume
that the rest of this is gonna go flawlessly.
Like that.
Like this.
Like this.
So, Peter, once you get to the end,
you're gonna close this with what's called
an Aberdeen Hitch.
Okay.
So, take your post.
Again, we're protected here.
And get your right hand through that loop.
And you're gonna go grab your post.
And bring it through your knot.
Don't let your loop get too small.
Oh, okay.
Okay, so I got one.
Good.
Do another. Do another?
Tension on the post.
Don't let the loop get too small.
Pull on that and that'll go down.
Pull on just the bottom one.
Just this one, there you go.
Just that bottom one.
Good.
And then one more.
One more.
Put that whole thing through.
Yes.
Yep, nice.
Very good.
Oh no!
Okay, go ahead.
Spoke too soon.
Okay, now reload your needle.
All right, so now you're gonna
bury this knot.
So, just take a bite behind it
and come out over here.
Do I wanna evert like that?
Stop holding your pickups like that.
Come on buddy.
Oh, oh no.
Oh no.
Oh god.
So, just pick this up.
That's fine.
At this point, the patient has healed miraculously.
Is awake.
Is thanking me profusely.
Yep, ready to be discharged home.
So, then your assistant cuts this.
And then, once you're done with the suture
you pass it off to the scrub protected.
And you say needle back.
Needle back, thank you.
And that's that.
And look how nice.
Look how beautiful that is.
The thing you did 80% of.
[laughing]
The point of this is that the suture is hidden
so they don't need to get them removed.
And that they just dissolve.
All right, Peter, are you ready
for the next lesson?
Yes, please.
Okay.
[light music]
Nurse, bring in the patients.
I've never seen anything quite like this doctor.
Most severe case I've seen yet.
All right, what are we gonna do with this?
I think there's already some sort of thing goin'.
I see a little bruise.
Well, I think first, we'll make
a little laceration then we'll close it up.
Sometimes you have to hurt things
to heal them.
So true.
Two bananas were harmed in the making
of this video.
Yeah, and is this how you would
make an actual incision?
No, normally an incision is with a firm hand
and a straight line, and just all the way down.
Yeah.
It just depends on what kind
of operation you're doing.
And so, where would you see this?
This is, in a skinny guy
like you, inguinal hernia.
Wonderful.
Yeah.
Well, let's just pretend I'm stitching up
my own inguinal hernia.
There you go.
Okay.
So, for this particular model, it's best to close
a banana laceration with a simple,
interrupted nylon suture.
Orthopedics surgeons will use it.
ER docs will use it.
But, it's sort of a simpler,
more straight forward way to close.
Okay, so this is just gonna pickup
on the skin, take a nice bite,
come right across.
So, how much room should I leave behind
for the knot.
You wanna pull through 'cause you're gonna
put a couple of these in.
So, and then, which is my post?
Is this my post?
Yeah, protect needle first.
Oh, protect your needle.
So, the filament that we're using,
what kind of grade is this,
what thickness is this?
So, this is a three-O nylon.
So, nylon is a monofilament, non-absorbable suture.
And three-O is slightly larger than
the four-O you were just working with.
All right, so we got it knotted, kind of.
So, then I would actually trim your tails
and you would put in a separate knot.
That's the interrupted.
Oh, so each time.
As opposed to running.
So, as you can see, I did what you did
and then I cut my tails and then I started again.
This is called an interrupted closure.
Is that a trim the tails?
Start over.
Good.
All right.
What are your pickups doing right now?
Two hands.
What are your pickups doing?
Gonna rip.
Careful.
Okay, so when it's really short,
you do something that the orthopods
and the ER docs do, but the general surgeons
don't do, which is called an instrument tie.
So, it's the same knot, but you're
just gonna do it What?
with your instrument.
And again, general surgeons
don't usually do this.
Why didn't you show me that one?
Because it's cheesy and it's not nice
and it's not delicate and it's not civilized.
It looks easier.
It is easier but it's not civilized.
So, I mean, you've got the basic skills down,
the knot tying, the suturing.
I think the things that would
get built up to be a little bit more
realistic is a wide open body cavity,
blood everywhere, everyone's yelling,
patient's not doing well, you're really nervous,
you're exhausted, that's probably
a little bit more real life.
This is suboptimal skin conditions
we're dealing with here. Indeed.
Yeah, your resident may have to redo
your skin closure on this one.
But some patients are more difficult than others,
I wouldn't take it too personally.
Well, Annie, thank you for taking the time
to show me all this stuff.
May it never come in handy but I'm glad
that there are people like you
to make sure that it does.
Should always shake hands with your assistant
before you leave the OR.
That is what that is.
[people clapping]
[light music]
Starring: Annie Onishi
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