Hello everybody, dear colleagues, wherever you are around the globe, hope you're healthy and safe from this COVID-19 pandemic we are all suffering from. I'm Doctor Stefanos Slavakis, veterinary surgeon from Greece. I'm the head of the veterinary referral clinic of Siy Veterinary Hospital at thessaloniki, and also work in private practise at et Referral Surgery centre.
Currently, I'm the president of the Elenipan Ban Society. Before starting this webinar, I'd like to thank the organisers. And Anthony Chadwick, the webinar vet for inviting me in this global veterinary event to share with you my knowledge about sutures.
So this is the outline of our webinar today. We're going to talk about such characteristics, such material, sizes. Needles, we're going to talk about suture patterns, suture selection, not tying, and before closing, I will give you some.
Tips on how to prevent yourself from se related complications. We're not going to talk about these materials today, tissue adhesives, clips, masses, and staplers. This is A new webinar probably in the future.
We're going to stick the sutures and starting, I'd like to say that the suture role is to provide hemostasis and support, healing tissues. We do know that different tissues have different requirements because they just heal at different rates. We do know that musclesapcu tissue, sapcutisues can need a few days where fashion needs more few weeks and tendons need a few months, .
And of course there are some factors that may delay healing like infection, malnutrition, obesity, immunosuppression, certain diseases like chronic renal failure, neoplasia, Cushing's, and diabetes, age, and species. We do know that dogs are healing their wounds faster than cats. So when choosing sutures, we have to choose a suture that can support tissues until healing, and the very crucial part is that we should know suture characteristics.
We should know the tissue healing profile and the patient wound healing ability, and of course, we have to know our own preferences. But are there any other criteria? Of course they are.
We have so many sutures today. So we have to know if we want a cosmetic result. And we need to know the cost of our sutures.
So, let's see how sutures are classified. Sutures are classified based on their origin as natural or organic. Synthetic and metallic based on their structure are classified as monofilaments, having just a single strand and less tissue drug and multifilaments with multiple strands which are twisted or braided together.
These tis have greater capiarity, may harbour bacteria, but they are more pliable. And based on their tissue behaviour, sutures are classified as non-absorbable and absorbable. Absorbable sutures are further classified as short term, mid-term, or long term based on how many support they provide to tissues.
Now, when the sutures are implanted in tissues for non-absorbables, we do know that they are encapsulated or walled off by the fibroblasts. For absorbable sutures, we do not, we do know that the natural ones are digested by the tissue enzymes or phagocytti. But the synthetic sutures are all broken down by hydrolysis.
Let's see now The ideal suture. The ideal suture should have an adequate tensile strength. Should lose its tensile strength at about the same rate as the tissue gains strength.
Will be finally absorbed with minimal tissue reaction so that no foreign material remains in the wound. And of course, it should react minimal with tissues, should inhibit bacterial growth, should be easy to handle, should hold securely when knotted, should resist shrinking in tissue, should be non-capillary, non-allergenic, non-electrolytic, non-ferromagnetic, easily sterilised, and of course, inexpensive. Well, hello, hello.
This ideal future does not exist. But we have sutures that are very close to ideal. And these are the suture materials that are more widely used in surgery today.
And we're talking about monofilament absorbables like polycaron, which provide the short-term support, licomer. Providing mid-term support, polydioxin and polygon providing long-term support. We have multi-filament absorbable sutures like polygloin 910 or latamer providing short term support, or mid-term support.
And of course, we have multi-filament non-absorbables like silk. And monofilament non-absorbables like polymide and polypropylene. And as you probably see, all these sutures have some colour codes.
We do know that polygrecaron sutures are orange. The packages are orange, and we do know that polyglyphine, for example, comes in a purple package, polypropylene in a dark blue, polyamide in a green package, and silk, for example, in a light blue package. There are many suture manufacturers, many, you see here, manufacturers like Cruz, Wetsuture Aan, Covidian, Medtronic at the moment, Brown, and there are certainly many, many, many other more, at the moment producing sutures.
And the technology runs very fast. A few years ago, we had the launch of the suture las antibacterial series. We have sutures that were, Impregnated with riclozan, mainly for human, surgeons, but even in human literature, papers have failed to find any evidence demonstrating the protective effect of these suizures on SSI on surgical site infection occurrence.
At the moment, we even have some nautless barbed sutures with either bidirectional or unidirectional barbs placed in a helical fashion around the strands. These sutures are loads and tissues. They have multiple anchor points, and the good thing is that the tension is distributed along the suture lines without the need of any knots.
This is an example of how the sutures work and you can see here the closing of fascia, we go from Caudle to cranial, and then we go back for two additional passages, so we cut the suture and we're done. No knots. Very simple, very nice, for those who like to work with this kind of knotless sutures.
Talking about properties and characteristics, I know that in any textbook, in any surgical textbook, yet that we read, you will find, we will find information about all these characteristics that are very, very well written. The good thing is that the best we need to remember is about future characteristics is how they react with tissues. This is very important.
The tensile strength, they're not security. And the absorption rate. Now, how do we choose those features?
We need to choose three different things material, size, and needle. And believe me, all this information are written in their books. So simple.
This table is one more table of the many that you probably know from textbooks. What I want you to remember from this big table is that the tensile strength of the sutures remaining after some weeks of implantation is written here. So if we are going to choose a suture like polyglactin 910 by a code rapid or quick or fast.
This is the multifilament absorbable suture that after 2 weeks of implantation has no tensile strength, which is about 50% of 5 days and it's about 0% in 2 weeks. Poli the cap from 25 sutures like monorel or monosin, absorbable monofilament sutures. This provides short term with a very high initial strength and at 2 weeks, the remaining tensile strength is only 20 to 30%.
For polylycholic acid, 50%, the remaining strength at 3 weeks, for glycomer, 40% at 3 weeks for polydioxinon, 60% at 6 weeks. This is a long-term tissue support suture. About silk, keep in mind that silk has a highnaal strength, but After 2 weeks, The remaining tensile strength is only 70% and at one year is 50%.
Severe tissue reaction. This is the bad thing about silk that it produces severe tissue reaction and when you compare this with polypropylene. Polypropylene produces minimal tissue reaction, and this is something that we are going to see in the next few slides.
So One long term support is needed. For the renal hernia, for example, or for. An abdominal closure for the linear alba or if we have any considerations that healing may be delayed, we have to use.
Futures that provide long term support either Non-absorbables like polypropylene or absorbables like polyoxyon or polylyconate. About polypropylene, keep in mind that this the less thrombogenic suture that we have in our arsenal and that that thing makes it excellent for vascular surgery because it produces minimal tissue reaction. Now, how do we choose sizes?
Well, when we choose a suture size, we have to know the tissue strength that we're going to suture and the mobility of the region where the suture will be implanted. The more ow The suture has the more thin it is. Lessos, thicker suture.
In this table, you see that at the moment, the most popular way of of charting sutures are is this USB. The table comes from the United States of America. The sutures that are in the green lines from 0 to 40, these are the most popular sutures used today, in veterinary surgery, in veterinary general surgery.
Some more tips. Choose the smallest suture diameter that adequately hold the tissue to be sutured, and the reason I say that is because in this way, you minimise trauma. There is no advantage using a suture that is stronger than the tissue to be sutured.
And we should always try to avoid large suture sizes because they cause increase. Tissue trauma, they cause changes to tissue architecture and of course, as you probably can understand, they increase the foreign body material that is left in the wound. Don't forget that sutures are foreign bodies and keep that in mind when choosing sutures, choose a suture that produces less foreign body material in the wound as possible.
About needles, how do we choose a surgical needle? First of all, we need to know the type of tissue to be sutured. We need to know its ability, it's density, its elasticity, its thickness.
We need to know the wound topography. Do we have a narrow wound, a deep wound. And of course we need to know the needle characteristics.
Is it a waged ant or a night ant in the length of the needle, the diameter of the needle, and The needle Consists of three parts, the wage. The tip and the body. The length of the needle is the distance between the switch.
And the needlepoint. And for veterinary surgery, the most popular needles are those having a length between 16 to 40 millimetres. There are various types of needles, either straight or curved.
Straight needles are generally used for easily accessible tissues like skin or to repair an oral hematoma. For example, curved needles are most widely used for less accessible areas like the body cavities. And the shapes are categorised based on 8 of a circle.
For general surgery, we use 3/8, half circle of 5/8 of circle, depending on the tissue and the topography of the wound. Ophthalmologists like to use, this, 1/4 circle, needles, but the way we, we're choosing is just the same. Choose a needle based on tissue characteristics and tissue location.
So we have Cutting needles for skin. We have reverse cutting needles. Which can be used for reconstructive surgery, skin flaps, or for GI surgery, you have side cutting needles for eye surgery, as already mentioned.
We have taper needles, excellent for subcutaneous tissue, fascial muscles, urinary bladder, and the GI tract, taper cut needles for tendons, ligaments, and the vascular grafts, and blunt needles for nchial organs like liver, kidney, and spleen. Now let's talk about future patterns. Oppositional future parents are the best parents to promote healing.
With a positional patterns, we are having a close approximation of tissue edges, and this is the best thing if we want to have a fun healing process. With inverting patterns, tissues edges are turned outward facing the surgeon whilst inverting patterns, the tissue edges are turned inward away from our site. We have interrupted patterns like the simple interrupted, the horizontal or vertical mattress, cruciate pattern, and the very popular gumbi pattern, which is an excellent pattern for intestinal surgery cause it reduces because of aversion of.
The intestinal mucus and during suturing. Continuous suture patterns like the simple continuous or the Ford interlocking and the well-known Lambert condo and cushing patterns. These are very popular.
Also, Lambert, condal, and cussing patterns are all inverting patterns. With coal being the only one from those three that enters the lumen of the tissues, Lambert and Cushing patterns are seromuscular patterns not entering the lumen of the organs. And keep remembering, remembering that when we're talking about the GI tract and the urinary bladder, we have the submucosa, which is the holding layer.
This layer should always be included in our suture line. This is the reason why a suture line may be the he after tuturing. Now, choosing features what we need to consider.
First of all, we need to consider time. We need to consider how long the suture must support the wound. We need to consider if there is any risk of infection, if there is a risk of infection.
We shouldn't be using multifilament sutures because multifilament sutures may harbour bacteria between their strands. We need to know what is the suture material effect on wound healing, and of course we need to consider the size of the suture and the size of the needle, because a big needle may traumatise. A tissue that shouldn't be traumatised.
Don't use, for example, a big needle, like a 40 millimetre needle to su your intestines. All right, you should use a more delicate needle like a 16 millimetres, for example, or a 19 millimetre, for example. And Let's see in this chart, for example, the urinary bladder, you can see here that the urinary bladder at 2 weeks.
After surgery, gains almost 85% of its initial strength. That means that to support this bladder during this two week period, you need a suture that can last for those two weeks and Going to the chart here, you can see that sutures like monoquil or monosy provide the long term support that is adequate for suturing the urinary bladder. In addition, we go to fascia, the last line here, you can see how slow fascia heals, and that is why for suturing fascia, we need a suture that provides long-term support like Pull the action on or pull click on 8.
60% remaining tensile strength at 6 weeks. Very important to remember that. When it comes to stomach this, Yellow line, you can see that in 3 weeks, the stomach regains about 70% of its initial strength, so we need to support wound healing for 3 weeks and that means that we can use the suture light.
Bin or PDS. Suture skin. For skin, we have two main options, either placing skin sutures or performing the cosmetic intradermal closure.
Both, of course, are acceptable. If you use skin sutures, keep them loose. My mentor used to say that tight stitches incision itches.
We don't want this to happen because it may cause some incisional complications. And for skin, we use a synthetic monofilament suture material, 20 to 4 out on a capping or the reverse capping needle. In for interlocking crushed, simple interruptive pattern, or even using staples.
For those who like to use polymerri caprolactam, this is a material like supramate. Keep in mind that skin irritation is often seen. For intradermal closure, I'd like to use monoquil or anything else.
Like Paul Dearon 25, depending on, the size of my patient from 20 to 40 on a reverse cutting needle is the best you can do. We have a cosmetic intradermal closure. This is my favourite skin suture that I use.
It's the crucial pattern. This is the crucial suture, this is how it is performed. This is a nylon suture.
It's a very fast pattern to use for skin closure. We try to keep them loose, try to keep your knots away from the incision. And a small variation of this one.
Is reversing this and putting the cruciate beneath the skin. Both work, work fine. Depends on your preference, what you're gonna do.
I like them both. Keep them loose. This is the best tip I can give you and keep your knots away from the skin incision.
Staples can also give you some rapid and precise closure, as we have already mentioned, but for staples, we need a whole new webinar to talk about. This is how an intradermal looks like. This is a patient who has been in the OR for a prostatic cyst and this is a perineal hernia where the skin is closed with.
Staples. Now, sturing the apicanous tissues, remember that we remove skin sutures in about 10 to 14 days with some exceptions like for hematoma where we may stay, we may leave the sutures for as many as 3 weeks. That means that we, when we are sturing the sub-Q, we need to use a synthetic absorbable switch material, either monofilament or multi-filament, no problem with that.
20 to 40 on a taper needle, simple continuous and positional pattern is the best we can give, . Try to take some vertical bites when you do this kind of turing. In this way, you have a great approximation of tissues and remember to bury the knots.
When beginning your incision and when ending your incision, the knots should be buried very, very well in order to avoid any problems with the incision because if you don't bury them well, they are very annoying for our dogs and our cats. Regarding the linear albi and FASA I've already told you that FASA heals relatively slow, regains only 20% of its initial strength 3 weeks post-op. That means we have to support, this FAA for long term.
We need a suture that provide long-term support. So that is why we use a synthetic monofilament suture material either absorbable like poly production, for example, or a non-absorbable like polypropylene, which is less favourable because it's permanent and we don't. Need the permanent suture when we can have a suture then can be absorbed, like, PDS for example, and that makes our life easier because we have less foreign body left in the wound.
Sizes depend on body weight from 1 to 40s, on the taper needle. Simple continuous positional suture pattern is the best choice. Many people ask.
What is the distance between the teachers? Well, There is no easy answer to that, but as a rule of thumb, I can tell you that there is no smaller distance should be no smaller than the thickness of the tissue layer to be sutured. You will probably see in a book saying that you, you, you do 33 millimetre bytes with 3 millimetres apart or 2 millimetre bytes with 2 millimetres apart, etc.
I, I think that the right answer is no smaller than the thickness of the tissue layer to be sutured. Regarding muscles and tendons, muscles have a very poor holding power. They are difficult to suture, so we need a synthetic monofilament absorbable suture.
To for out on a taper needle on a simple continuous or interrupted pattern. For tendons We need a strong, synthetic, non-absorbable, and minimally reactive material like polypropylene. We have to use the largest suture that will pass without causing any trauma to the tendon, and the sizes are approximately 1 to 3 odd on the taper or a or a taper cut needle when the patterns that we use for tendons are the well-known re-loop, banal or far near, near far, as you see in the slide.
Regarding suturing holo viscous organs like the trachea, GI tract, stomach, intestines, urinary bladder, or gallbladder, remember the two old words leakage and lumen. Leakage should be avoided and lumen should not be reduced because if it is reduced, it may cause stenosis, especially when the lumen is very narrow, like. Intestines.
And in order to achieve those two things, a bad leakage, we have to engage submucosa and to have a safe distance between sutures. And regarding lumen, we have to take into account if we're going to do a single or a double layer closure. Because a double layer closure may produce a narrow.
Lumen For example, in the intestines, a double layer closure is not a problem with the stomach. It's not a problem with the urinary bladder, but it may be a problem with intestines. So, generally we use apositional suture patterns and simple continuous appositional suture pattern is all that it needs for the stomach.
But many people like a double layer closure. The first to, a simple continuous and a cushing. After that, it's OK, no problem.
But for large lumens like the stomach or the UB, double layer closure is OK. For small lumen, simple positional suture pattern either interrupted or continuous lines are. The best choice.
So synthetic absorbable monofilament switching material for hollow viscous organs, 20 to 5 off a taper needle, simple continuous or interrupt a positional patterns. Remember the gambi pattern, and excellent pattern for intestinal surgery. Try to avoid non-observable such materials because they may be calcinogenic, especially when used in the urinary bladder or the gallbladder.
For parentchimal organs, we have to avoid multifilaments which materials because they tend to cut through these tissues because of their increased drug and they also may potentiate infection, things that the surgeon hates. We go so for a synthetic absorbable monofilament material, 20 to 5 volt. On a blunt needle.
ICWs infected or contaminated wounds. For these wounds, we have to avoid placing any sutures if possible. And certainly we have to avoid placing multifilament non-absorbable tissues because they may cause infection or even fistula.
If you must suture this wound, you have to use a monofilament absorbable suture. And if you want to know what happens with this dog here, Here's what's happening. This is a no suture technique.
We just use medical honey, and that, and that is the result. After one month, no stitches. Keep this in mind.
For blood vessels, we have two options. One comes for ligations, a synthetic absorbable monofilament or multi-filament material. 0 to 40.
Is all that it takes depending on the size of the pedicle that we want to ligate or the vessel we want to ligate. For large blood vessels, large blood vessels may be ligated with a non-absorbable such material like silt, a PDA, for example, or polypropylene. For anastomosis, for those who are gonna anastomo blood vessels, they certainly gonna need ramification.
Magnification to do that and polypropylene 100 is probably their future of choice because it's the less thrombogenic suture that we have available today. Regarding the oral cavity for the tooth extraction sites for maxillectomies, mandibulectomies, palate surgery, and tonsillectomies, synthetic absorbables, monofilaments which materials are fine. Many people like to use polygloin due to its softness.
It's OK if you want to do that. 30 to 4 out on the taper needle is. The best choices for your cavity.
This is a urinary bladder, We are removing a polyp from this bladder and we are closing it with polyar cap on 25, size 4, taper needle, 3 of a circle, 90 millimetres, . We tested for leakage and if this continuous line is not enough. You can make some additional switches and interrupted like here and here and Look at the video to see how we use our needle holder to send a suture to the point that we want to go exactly in the urinary bladder.
I always like to use my section to keep my field clean of urine during suturing, urinary bladders. Very delicate way of working. This table, is included in the webinar notes.
It's a big one and it will help you to, decide which suture and which size you will use depending on what you want to do. For example, for, muscles you can use for a cat, a 40, either monofilament or multi filament suture like polycapron, glycomer, or polyglycerin. It's only a notes.
I won't say more. No tying, my favourite topic, knots. The knot is the weakest point of the future.
It consists of at least 2 throws laid on top of each other and tightened. The secure way to form a knot is by superimposing square knots. Remember that when tying knots.
Try to avoid extensive tension unless Ligatures are applied for hemostasis. You can do your knots either by using instruments, having instrument ties, or by using your hands, either with one hand tight, one hand ties, or two hands ties. With one-handed ties, tights are faster tied, with two-handed, you have more precision.
So it depends on what you want to do. To be a good surgeon, you have to master some ancestral knots, and these are the square knot, the surgeon's knot, transfixation knot, slipknot, and Miller's knot. And this is how you can do.
Your sleep not, you can practise and exercise it. In your lab before doing this in a live animal. 3 square knots Superimposed and you're done.
Preferably with an absorbable. Monofilament suture. Because it's easier to manipulate.
The mill is not. With your hands. Very easy also.
To perform and once, once you master this future. This, suture ties, you will never do another one. My, preference is to do a miller knot for almost any ligation I do.
You can do this with your hands, or you can do this with instruments, and as I will show you in this video. This is a vasectomy due to pymitra. We are making this small window to the broad ligament, and we are placing our carmal forceps.
Force of number one, For 2. Forcep number 3. This is the 3 clamp technique.
Then we're going to cut. Just beneath or. For 3, to remove the ovary with the mental bursa.
With either your seizures or your scalpel. And then you will take your suture, at this video I think this is. Polyglain 910.
You form The knot And After forming, you are, you just beneath. The, the first lump. And you tie the knot.
Remove clump number one. And then you can use your instruments or your hands. In this video, I will use my hands to perform at one-handed tie.
And that's it. 3. Square notes are superimposed, and we're done.
Then you cut With your seizures. You grasp the pedicle with your some forceps. I would like to have a clean field.
Release the car malt, check for haemorrhage, return to the abdominal cavity, and that's it. Oops, abdominal closure. Let's see how we're closing the abdomen using sutures.
This is a simple continuous oppositional future pattern with. A amount of filament absorbable suture, it's polydioxinon in this case. You can see how we try to identify direct sub dominance and include only.
The fascia To our line, we're taking good bites. Of the fascia Sib continuous positional future pattern. I'd like to say again that positional patterns are the best to promote healing because With with these patterns we achieved close approximation of tissues as William Halste said, almost a century before.
Take care to have a good distance between your bites. And shown here. This is how we closed the abdominal cavity.
With the self-logging Aberdeen knot. You can use the same suture if you want. To go back and do your subcutaneous tissues as sewn here, or you can cut and use another suture for.
The sap cube depends on your preference on what you have available. For subQ, you can use almost any suture, but I think that monofilament sutures are the best choices. Vertical bytes as you see here.
And try to eliminate that space by attacking. The suture to the abdominal incision. You made before.
Semicontinuous appositional pattern also for the sap cube. And you need to close with Aberdeen note again at the end. For skin closure, you can use anything you want.
You can use staples, you can use, you can do an intradermal, you can do crushed pattern. Many, many choices for these patients, choose the crucial pattern. Remember that when you're putting skin sutures, you have to keep them loose.
It's best for the patient because if they are not loose, this may cause some incisional complications. You can see here the cued pattern. The variation of the crucial pattern, this is the X forming below.
The skin incision, And this is the way. That one. Tightening your sutures, you keep them.
Loose. Suture-related complications don't use multi filament sutures in infected or contaminated wounds. I, I did show you before the example of of even not using sutures at all, .
Don't use non-absorbable multifilament features in hollow viscous organs because they may be calcullogenic. And certainly don't strangullate tissues when suturing. Try to use a positional patterns if possible.
This is the best you can do. And of course, try to use sutures that cause minimal tissue inflammatory response when you expect postoperative stenosis, as it may happen with urethrostomy, for example, or for a tracheostomy. And This is the end, .
Let's wrap up what we've said so far. What I'd like you to remember, regarding suture choices, choose sutures that provide long-term support for tissues that heal slowly. Use sutures that provide short-term support for tissues that are healing fast.
Remember that multifilament sutures may harbour bacteria between their strands. So if there's a risk of infection, avoid using multi filament sutures and also avoid oversizing. About, our patients, keep in mind that our patients' ability to heal is very important for us in order to choose a suture.
If we do know that we have a problem, we have a patient with a chronic renal failure, for example, that means that male have some healing problems, so we use a suture that is providing long term support or it's even non-absorbable, no problem. And when it comes. To us, our surgeon's part.
Don't forget the holding layer. Don't forget submucosa. Use the submucosa wherever it exists.
This will provide you a secure closure and of course, I do know you do know that our preferences are based on our training and on our expertise. Anyone may have preferences. I even have my own preferences regarding futures, but when choosing futures, your choices should always be evidence-based.
So, time flies quickly. This is the end. The scenery is from Greece.
I hope that when the pandemic goes away, you will have the chance, if not already have to visit my country. If you have any questions about today's webinar, please don't hesitate to send me an email, and I'll answer any question, you may have. Try to reach me through social media.
It's, it's fine with me. Enjoy the rest of the VC 2021. I'd like to thank once again Anthony Chadwick and his team for inviting me in this event.
Everybody Bye bye, have fun, and stay healthy.