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In this on-demand teaching session, renowned retired cardiac surgeon, David Regan, leads an engaging class on surgical knot tying. With years of experience under his belt, including roles as the past director of the Faculty of Surgical Trainers for the Royal College of Surgeons of Edinburgh, David's session promises to enhance surgical skill sets. Presented in a patient and detailed manner, he explains the concepts and practices of knot tying, from the historical and cultural significance of knots to their importance in medicine. David elucidates how to master different types of knots with both hands, using clear demonstrations and easy-to-follow guidance. Addressing medical professionals across the globe, this session is an invaluable opportunity to learn from a distinguished expert in the field.
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The ability to secure a surgical knot is fundamental to safe surgical practice even at depth. BBASS has deconstructed this skill to highlight the important elements. We offer many fun low fidelity models that will enable you to under sand has to secure a knot. It is not easy at first - pun intended. Many videos on knot tying do not highlight the essential elements. We hope that you have a better understanding after the session.

Learning objectives

1. Understand the fundamentals and principles of knot tying in surgery, and be able to explain why it is important to master this art in surgical practice. 2. Learn and practice the practical techniques for tying different types of knots, using both hands, focusing on efficiency and precision. 3. Recognize the difference between a crossed and uncrossed (flat) knot, and be able to tie both with confidence and competence. 4. Be able to identify potential mistakes in knot tying that can weaken the knot and pose a risk to effective surgical practices, and know how to avoid these. 5. Engage with the history and context of knot tying, considering its broader application in different cultures, and use this understanding to enhance personal knot tying skills.
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Computer generated transcript

The following transcript was generated automatically from the content and has not been checked or corrected manually.

Hello, good evening. Good afternoon. Good morning. Good day, wherever you are in the world and welcome to the Black Belt Academy of Surgical Skills. My name is David Regan. I'm a retired cardiac surgeon in Yorkshire in the United Kingdom. The immediate past director of the Faculty of Surgical Trainers for the Royal College of Surgeons of Edinburgh. And we are accredited by the Royal College of Surgeons of Edinburgh and a visiting professor at Imperial College, London. If this is your first time, welcome. And if you're returning, thank you very much. Indeed. And I must thank me for connecting us across the globe. We're now reaching 100 and two countries and joined this evening by Qatar. So we literally are from Albania to Zambia A to Z in countries. Thank you very much. Indeed. We have 4244 people on Facebook, 450 on Instagram and 1469 on Twitter. I do use Twitter because I find it difficult to say X this evening, we're going to talk about knots. It's something that we learn very early on in surgery and does require practice and I recall many an evening practicing on chairs right arm, left arm. And it's a skill that I think you should be able to do with both hands. It is actually economical to do it with your non dominant hand whilst holding instruments in your dominant hand. But there are certain principles involved. And I would like to outline those principles and I hope that we've been able to put our one handed surgeons not on me for you to look at and to practice it has 22 stanzas, seven lines each. And if you follow it, word for word, it'll work for both your left and your right hand. Now, a knot is actually the condition of taking a long flexible object and you make a knot, you can tie your hair in a knot. And the knot is also found in wood as re related to knob. No, and knuckle are not related to knowledge. Not, not time has a rich history and expands many different ci civilizations and time periods. The ink only written language was the system of knots called rippers or talking knots. Knots were also used by the ancient Chinese and the Chinese book of changes. Almost 2500 years old Association Knots with agreements and contracts. I did think when I read this that maybe tying ourselves in knots is an antithesis to actually making agreement. The bitter end refers to the working end of a rope thus intended to be tied off to a bit or clicked like fastening object on a dock. So if the Shoman has Mi Throne his line or must tide his move as the ship comes in, he literally left hanging on to the bitter end and we'll be using the bitter end as we learn to tie knots this evening. What's interesting we talk about feel all the time in the Blackard Academy and the feel comes from the pulp of the fingers. The feel of the rope is called its hand. A hunk of rope is basically and looped bundle of rope. A band is a knot that ties the two ends of the ropes together and a hedge fixes it to a fixed object. The short section of the rope that does not cross itself is called a bite and we will see that bite in tying a surgical knot. If it crosses itself, it forms a loop and part of not tying is to be able to get that bite through the loop and take it down. The problem is is that and all the videos that I've seen on youtube describing not time. This essential element of taking this bite through the loop is not demonstrated and not described. And you're left wondering what on earth the fingers are doing. Now, there's one knot that we use in regular daily practice that you probably have not paid attention to excuse the pun. And that is how to tie your shoelaces. If you tie your shoelaces correctly with using square knots, the loops should lie horizontal across the shoe. Whereas if you tie them as an uncrossed knot, the loops end up down the shoe and it explains why your shoelaces has come undone. Now, from climbing point of view, we always say square knots or reef knots are very secure until you take one end and you flip it over. And all of a sudden it ends up as a girth hitch by locks head knot which comes undone. Any time you tie a knot, you weaken it. And a rope typically breaks at the knot. And the strongest knot that you can use is a figure of eight follow through. And in pool tests, it breaks at 75 to 80% of the knot breaking. And there's a whole academy in science behind us that we have actually described before in the Black Belt Academy climbing rope, quite frankly, is a misnomer. Rope refers to the raw material. Suture refers to the raw material and once cut for a specific length and given a designated purpose, the rope should be called a line and in surgery, it should be called a ligature. What is interesting in the history of NAS humans, tie knots, gorillas, TNAS and weaver birds tie knots. Nobody else in the animal kingdom can tie knots. But it is essential for the surgeon to be able to tie the knot. Of course, it is, carries a whole lot of connotations and tying the knot is part of the matrimonial process. And is there in Celtic folklore. What I'd quite like to do now is to take you over just to explain in detail how to tie a knot and show you that flick at the back of the finger to bring it through the loop to make the basics of or not. So let me put things aside for a moment and bring you over to show you the difference between a cross knot and an uncross knot coming over to the top. Ok. And I'll focus down. And what we have on the table here is what you would recognize is right over, left, left over right, a reef knot and that is a flat knot and you will see that it sits flat on the table and that is called an uncrossed knot or flat knot. And during my training, there was only one surgeon at the beginning of my career who watched me tie knots and would call out crossed or uncrossed, uncrossed, crossed, flat, crossed. So it's synonymous. But the difference is this, you'll see is not sitting flat on the table and that is called a granny knot or a cross knot. And as you walk during the day that comes undone, whereas here as I walk during the day, this tires itself, but if I turn it over, this knot would very quickly become a large, see and come undone. So the first thing to think about when tying knots and you need to watch is the knot flat or uncrossed and we'll go through it with the right hand and the left hand. Now, you do not need a plastic, not tying rig. You can make it out of a rubber band, a couple of pencils, a brick, a block of wood or a book. And I'm gonna take you down and we're going to go through how to tie a knot and try and remove some of the mystique behind it. So I want to get the right angle so you can see what's involved. And I'm looking at this thinking it's a little bit far away. So you wanna be able to see the hands. There you go. So we start off and a shoelace is rather nice that at the end is called an Aglet. We have mentioned that before and it tidies up the ends of a rope. You have a short end in gray here and a long end in white. And I'm picking up the short end, finger and thumb, holding the end. I am going to, I think I'm gonna swap this round as I think about it. Otherwise you're not gonna see it, finger and thumb. Hold the short end and I'm gonna rotate, supinate my hand, supinate my hand like that and hold the short end out. Now, I'm going to take the long end and cross it over the short end. And I've made a loop by three fingers on the loop. The idea is now to get the short end through that loop. And I used my middle finger to flick that short end through and I'm catching it between my middle and ring finger and I'm taking it away from me and that is poorly described. I think I'm gonna swap this round so it's all white so you can see it clearly, sir. Short end, long end, I'm going to supernate my hand. Three fingers cross the long over the short. And I've got a loop there where my three fingers are and I've got a flick, the short end through the loop is the back of my middle finger. And as I do that, I catch it between my ring and my middle finger and I take it away from me and then holding it now between my middle finger and thumb and I'm gonna sweep round and hold the short end out again. Now I've made a smaller loop. Yeah. And I've got to get that bite through the loop, that small end through the loop and I flick it through and I catch it and I take it towards me and I put my middle finger down and I'm ready to do that again. And what you've constructed there is a square flat knot now works this with both hands and it's important that you work it out yourself that movement. Now, I call it and describe it as a figure of four people fed over and describe it a different way to demonstrate it. And remember it, I like to think of it as a figure four. So with my right hand now supernate long over the short and my middle finger is gonna flick the bite through the loop and I'm gonna take it away between my middle and ring finger and I'm gonna put my index finger down. We'll come on to this finger down on the mo in a moment. I then going to sweep it out and turn in to hold the short end out. Cross the long over the short and I'm gonna flick that short through and bring it towards me. Note what I did, I went from that way to that way my hands were working like a loon and in doing so I've got right over, left, left over right. And now I've got a flat knot and when you start realizing this and start going, it becomes a sort of rhythm and automatic and you should be able to very quickly realize a whole series of square knots on your rig. I would recommend you start off with a thick piece of string. I've got a sport shoe shoelace here. The aglet on the end helps me to remember to hold the end and enables me to think on the change and hold from index finger and thumb and middle finger and thumb. So let's just do that once more because you need to appreciate the bite going through the loop. So short end supernate long over the short, my middle finger is gonna flick that short end and that short hands my thumb and my index from holding the aglet and I'm flicking that through and taking it away, see how I'm holding it. And now I'm applying my index finger and sweeping that out, holding that out up, flicking the bite through and bringing it towards me. Let's do it with the other hand. Same principle. It is the same principle, short hand finger and thumb supernate long over the short. There's my loop with my three fingers in the back of my middle finger is gonna flt that aglet or bite through the loop. I carry it away between my ring in index finger and I place ring and middle finger and I'll place my index finger down. I'll sweep it out long over the short again. And I'm flicking that short end through and bringing it towards me. So my hands have done this and that is what we are achieving with cross knots, uncrossed knots and flat knots. Now, the important thing is is that that's all very well, but we need to bed the knock down first of all and they're not bedded down. There's two throws the same way and therefore two half hitches can be the knot down before you start securing it, see that it's actually strangulating my finger and I can bend it down and that is effectively two half hitches. Now, part of the practice of tying a knot is to be able to tie it without moving the object because all too infrequently or too frequently people are tying knots and pulling the object. I'm pulling the vessel. Now, if this was a middle rectal artery, if I didn't put my finger across the knot and I hope you can see it. I'm pulling across the knot, I'd be lifting this off the table. I'd be pulling the suture off the vessel and that is not a good idea. So, having secured it down, now I continue my throes ensuring that I'm alternating and throwing down flat knots. Sorry to interrupt. We have a question from you as Nina. When you bring it towards you, do you need to use the index finger again or is it just the, well, if you notice it when we did it the first time, it'll allow me to demonstrate and go back to the beginning because I'm alternating my fingers. It's a flow of fingers, think of a sewing machine and a, a loom. My fingers are doing this, OK. And my, the bedding of the knot is either my index finger or my middle finger depending on which way it is going. So let's just show you that again because this is an important element of not time and it part of why I called it flowing fingers. So short and long end supernate, create that loop and flick it through. Catch it and I've taken it away between my ring and middle finger and my index finger is free to bed the knot down my index finger now is going to be used to hold the short end out and I've created another loop and I'm gonna flick that short end through. Catch it towards me. Bring it towards me. I'm now holding between my index finger and thumb and I can put my middle finger on the knot. So between those three fingers, whether I going that way or that way depends on which finger is being put on the knot. But each time that finger needs to be put on a lot. So let me just demonstrate that with the other hand, I'm conscious of trying to get a good view on the camera for you so that you can appreciate that nuance that is poorly described. So I'm holding between my index finger and thumb. I'm super the short end out holding the long over the short, I've created a loop. You can see my three fingers in the loop. My middle finger is gonna flick the bite through the loop that short end through the loop. I'm gonna catch it between my middle finger and my ring finger and my index finger is gonna press that down. But as I'm doing that, my thumb comes in to hold the end. I'm now going to sweep out, turn in, hold it up, flick it through the loop and bring it down towards me again. And then you have a square nt. It's worth thinking about this and thinking your hand is doing this is not crossing over. Ok. It is not crossing over. You'll find one. You've started a natural rhythm appears getting started. Does I admit, feel awkward? So Yasmin II, hope that makes sense. And I sometimes remember it. There you go. Take it away from me and that's my index finger. She out, bring it towards me and that's my middle finger. All right. So my index finger away, it's you middle finger me. OK? Because you wouldn't put a middle finger up at somebody else. So I've often thought about this and literally have to consciously think about which finger is a way and which finger is towards me. Now, the fun thing about this is once you've started and realized that your hands are going back and forth, you can play a little game with yourself. How short or short end do you need a bit like limbo dancing getting this loop through? How low can you go? And there you go. I've probably reached my limit or I can squeeze your last one in. But that is OK. The short end. So coming back to tying a knot to an object on a surface, I use a coat hanger for two reasons. One, it is easy to lift off the surface. Two, you should be able to tie a piece of string to this without lifting off the surface and using this bed down two throws or half inches the same way, bed it down and then cross it over to the extent that it is secure on the surface. I should not be able to move this bit of string along the coat hanger. then you start securing your knots because the other important area of tying knots is tying in a drain. And if you don't secure a drain properly, that is a serious surgical problem. And it's very important that you're not on a drain needs to be secure. And in this circumstance, what we throw is two throws the same direction and so on a plastic malleable drain. What you'll find is that you take it down flat, make sure your fingers across the knot and now I can secure it. And how many throws you put on? I go for five for braided seven for monofilaments. And we'll come on to the throws in a moment. So I should be able to put that on a smooth surface and secured. Remember when you tie and drain into the skin and I reminded my fellows and say Phillipe Louis Philippe to actually put the knot on the dependent side. So it's not hanging, the drain is not hanging on the knot. There you go. You might not have a drain to practice with at home, but a piece of garden house is very much the same and tie your knot to the garden hose in a manner that you cannot move the knot at all. You now begin to get secure notes. Of course, this becomes more problematic when we start using monofilaments. So here's a monofilament and a monofilament you call is essentially a bit of plastic that's been drawn out, thinner and thinner and thinner and thinner. You don't have to go and steal sutures to get this to work because fishing line is a perfect alternative for doing this and it comes in all sorts of ways. So the great thing is is that you too can practice with different types of materials. And I wouldn't recommend that you start off on fine sutures. And I am conscious of the fact that you can't see this one against the background. But I'm demonstrating this because it's important that you get to feel the knot that if you pull too hard, it will break. So fine fishing line. There you go. And I've got it on here and it is secure. But what is very useful is not only fishing line but of course cotton and I like cotton. Because if you run the two ends next to each other, you hear rasping and it freeze and weakens it. And too often when I hear or see trainees tying knots, I can hear the strings, Ros Wing and creating friction against one another. I recall Mr Westby asking the scrub nurse for a syringe of water to put on the knots because he is tying them incredibly fast. But what he is also doing is tying them and rubbing the two ends against each other and causing friction. Now, this exercise was recommended on Twitter the other day is using the ring tag on a can to tie your knots. I've not fixed this can to the surface and I need to be able to tie this not without lifting the ca off the table. They do say things go better with coke and if you actually tie your knot securely using cotton on the surface, things will go better for you and they do go better with coke, your knots will be secure. But of course, not only do we have to think about flat or uncrossed knots, bedding the knot down by putting your finger on the knot. Our next challenge is to think about tying knots at depth and tying knots of death is a challenge when you start learning, but absolutely necessary because we're going to be inside the body. And what we've got here is a cup on a bit of blue tack and a pencil at one felling steep. And the idea is to use some cotton or a bit of fishing line. And I'll show you a little trick in a moment for passing this a depth very useful for a surgeon and very useful for an assistant. Did you hear that? I'm gonna rasp it again. I don't want to hear that rasping because that rasping is you rubbing one suture against the other. I'm not, I haven't got my finger below the knot. I've got my finger on the knot and when we're tying in aortic valves and I'm going, taking a trainee through an aortic valve replacement. We have 21 mattress sutures, 333, 18 mattress sutures to 21 mattress sutures around the annulus to tie. Yeah, what we rehearse is I asked them to say finger on the knot. And if I see the fingers on the knot, I will count one. They then permitted to put a second through. And if their fingers on the knot, I'll count too, they then put a third throw and we repeat until we get five throws on a braided suture. We can swap it around. They say finger on the knot and I'll only count one if their finger is on the knot. And in this manner, we can ensure that we've got efficient, safe knots at depth on the aortic valve with only five throws on each brain suture. You can imagine that if you start showing off and throwing multiple throws, 789, multiply that access number of throws by the number of sutures that is wasted useless, unnecessary movement. And what we need to be able to do with our cotton is to secure it on the pencil, such that I can hold the knot and not move the pencil through the cup. And in fact, move the whole apparatus because why not as a cure, simple feedback and simple tests. Of course, that's at one felling deep. But now we need to actually think how do we tie at the bottom of a cup? And this is a little trick to use it to use a curved instrument like a la and you hold it in upside down and you can hold it in your fingers like that. And I can pause this. Now, beneath that pencil, pick it up with a forcep and I've passed the suture around. You'll find it's impossible to pass the end of a suture loose into depth like that and expect the surgeon to pick it up, use a Roberts or la and literally bowstring it across place it below the object, allow the surgeon to pick up the string of the bow below the object and release simple trick. I don't need an assistant to do that. I've got my left hand practiced. And now again, I'm at depth. It's important to be able to tie your knot and get it down right to the bottom without lifting it off the c as you can hear, I'm deliberately showing you hear that rasping noise, that rasping noise you should not hear at all because in fact, you're weakening the suture five throws at depth finger on the knot. I know I am using mass to cut this cotton, but it is fine enough. And my scissors reach a depth note that I'm only opening the scissors as far as necessary to do the job. I place them in cut, take it out if you are asked to do that as a trainee and you're shaking, use a forcep as a fob to support you again in this exercise. Hold the knot and ensure that it is secure. We are tying at depth. It's party time, party time means I have got a big bag of party balloons. Fantastic. This you can use with games with your colleagues again, piece of cotton. Can you tie, just gonna hold the balloon down the side? Can you tie this balloon off in segments using cotton or fine fishing line and to secure a not, let's see. Note that I've paused at the bottom and this is not easy because I'm having to hold it down as at the same time as well. And you're gonna probably laugh as I'm going to be struggling to cure this in order to just hold it down that side. So it's not lifting off. Not so easy. I'm not having a good date on this one, but that's the fun thing about doing it live, isn't it? Oh, there you go. Didn't work. I'm gonna use a fishing line. This is a monofilament. I've got a reel on this side, many suture materials are offered as reels. It is an economical way of using sutures for ties because you're not cutting off l long lengths and lines at home. Ok. There you go. There was two half hitches down. Oops. And I've broken that. And again, it's a fine suture. If this was a RV video, we probably edit that out and you'll think. Wow, this is easy, but it's not easy. It's not meant to be easy or broken again. It is not meant to be easy. And these, these exercises are meant to test your skills. And for me this evening, it certainly is testing my skills. My fellows, Mr Caddy who's watching is probably having a little giggle to himself on this one as well as I'm trying to see the ends. Maybe it was the workout earlier. That was putting too much, too much pressure when you get the idea is that I'm trying to and I've got that too long now, I'm trying to tie this into sausage like segments as well as hold the balloon on the table. This is really going to test your not tying skills. So the idea is, is it you tie the knot? And I used to use surgical gloves, but I think that's expensive and there you go, the knots weren't secure because when I actually popped it, it all went like that. What I have to do is I need to go back and need to practice and think of how to hold that for you. So it works. It's a challenge, isn't it? I'm not one for giving up on challenges. Let's see if I can just hold it in my little rig, I've got here. Oopsie. No, it's gonna break on the balloon. Thank you. That's called live. Not time for you. Take a moment or two to blow up another balloon. But as we look at that and think about it on our time, the important things are one is that you understand how your hands move to ensure that you get flat, uncrossed knots, then you have to realize you need to be able to secure your knot down, embed it down, using your index finger or your middle finger. Depending on which way your hand goes. You practice the bedding of the knot down first by using an object on the table top. The Coca Cola can the coat hanger are good examples. Does it bite in to drain or plastic? A piece of garden? Ho can you secure the drain then progress to tying at depth such that you're not, does not move. But I think you'll agree that does not move. And lastly is part of party fun. Try balloons. These balloons have been in my bag for a while and we are using them at Leeds University the other day. I think we popped more trying to blow them up and whether they're slightly perished or not, I'm not sure, but I'm not going to make an excuse. I'm going to go away and try that again. But I'm mindful of your time. I'd like to thank you for joining us this evening and ask if there are any questions or observations from the audience, Gabrielle. Do we have any questions or observations from the audience? Well, we kinda have a combination of both. I'm just trying to think what's the best way to kind of put them. So one of them is like regarding the rasping noise when, when tying it to depth or a difficult field. Um Anything you want to add to that, what II was deliberately using the cup to highlight that rasping noise because the cup is using as an echo chamber. You don't want to hear that rasping noise as you're tying a knot because it means that the two strings are rubbing against each other. And what I noticed previously when tying a depth in the cup, the cup was a very good amplifier to demonstrate that rasping noise and I was not sure if you could hear it. If you could hear it. That's bad because I was demonstrating the bad. You do not want your sutures to rub against each other. Great. Thank you. And then from Rinku, um again, half observation, but can it be done on the side of the knot repeat that please Gabrielle? So the the full kind of comment is move hands flat and cross bend down. Can it be done on the side of the knot? Well, II am actually pressing when I'm pressing down, I'm pressing down on the side of the knot. So if you look at it, I'm actually pulling across the knot. I am not pulling the knot off. I am pulling directly opposite. So my finger is equal and opposite to the direction of tension. So I found particularly with 70 s 6080 sutures in cardiac surgery, your finger going down on a knot is not only bedding it down, but that feel also is across the knot. So you're not pulling it off to the side, you're pulling it directly across what you want to do. TTI and that finger on the knot is feeling it down and feeling the depth and feeling the tension. Thank you. That's all questions for me. And you can see that even fine fishing line, you can't see that as thick as the hair, start off with a piece of string and work out these simple principles and then start practicing using other material. You do not need sutures from theater. And one of the most innovative pictures I saw from a follower is they used human hair to construct or not. And literally your 70 or 80 or microvascular sutures that my fellow S Mr Ca uses in nerve reconstructions are that thin. So being able to feel a lot with the pulp of the finger is important and you practice until you can't get wrong. So I need to go away this evening and practice with my balloon a bit further. Such are not all fingers and thumbs. Thank you for your attention. Please fill in the feedback forms. Next weekend is Easter weekend and bank holiday in Lithuania and Gabrielle is on production. Uh She'll be on holiday. It is Easter weekend. So the Black Belt Academy is going to take a two week break and we will not be with you on the first or the eight, but I think it's the 15th of April, which will be our next session. I'll be coming to you live from Kuala Lumpur and Gabrielle and I have yet to set a time that is convenient. All this is available on catch up. Please pass the word around and we look forward to seeing you again on the 15th of April. Thank you very much indeed for joining the Black Belt Academy. And thank you Gabrielle and me for allowing us to connect to everybody from A to Z including Qatar across the globe. 102 countries. Thank you very much. Indeed.