Double ligation

RE: Double ligation

Neil Wheadon — Wed, 05 Dec 2018 19:00:36 GMT

[quote user="Sarah Keir"]Practising on my mug handle just now![/quote]

That's what convinced me. I use a piece of drip tubing (start big) wrapped around the leg of an anesthetic machine. The 'surgeons knot' had a gap between rubber and leg, pull as hard as i like and I couldn't reduce it, the 'millers knot' was super snug, very illuminating

Neil

RE: Double ligation

Sarah Keir — Wed, 05 Dec 2018 16:49:23 GMT

Practising on my mug handle just now!

RE: Double ligation

Linda Filshie — Tue, 04 Dec 2018 22:10:00 GMT

Miller's knot was a life changing revelation to me as well when I started using it a couple of years ago (I use modified miller's which I find easier to place). Interestingly it's not named after a person called Miller - it was the knot used to tie the neck of bags of flour from the mill!

RE: Double ligation

Neil Wheadon — Tue, 04 Dec 2018 21:30:48 GMT

I've now done 2 dog castrates and 3 cat spays using the Miler's Knot. A complete revelation.It's not easy at first having to think about where the ends are going and keeping the first loop loose so you can pass the end through it, but it's super snug.Even figured a way not to use a mile of suture material, so thanks a lot. Next stop the bitch spay. To anyone else give it a go.

Neil

RE: Double ligation

Helen Perryman — Tue, 04 Dec 2018 17:05:12 GMT

I remember having a dog transferred to me for out of hours care for monitoring post castration due to some haemorrhage. The transferring vet told me that she had TRIPLE ligated it 'as normal' so couldn't see why it was bleeding. I have to say that did not fill me with confidence! Fortunately, it did stop bleeding without us having to go in again but it did make me question the vet's surgical technique. The only reason I would double ligate is either to place a transfixing ligature above an encircling ligature due to concerns of slippage (e.g. a fat bitch spay), or if something made me question the efficacy of my initial ligature.

RE: Double ligation

Evelyn Barbour-Hill — Mon, 03 Dec 2018 00:28:56 GMT

[quote user="Beats"]if you find one good clamp you like in a kit you may count yourself lucky)[/quote]

Another advantage of being single-handed is that you can insist on kits being precisely to your liking. You can demote clamps you don't like, and if you are too tightfisted to do that, at least you know every clamp like an old friend, its little foibles and preferences.

RE: Double ligation

Beats — Sun, 02 Dec 2018 20:20:20 GMT

I do a single "stick-tie" if that is the correct term [needle through stump cranial to vessel, then round the vessel caudally, back through the stump cranial to vessel, then round the cranial aspect of pedicle/ligament (imagine figure-of-eight) on both ovarian pedicles in anything significantly thicker than a cat spay. I break down the ligament with fingers (easier to show than describe) or scalpel/scissors.

I often flip the straight long clamp over and drop a heavy instrument through the finger hole to keep it like that to have pedicle nicely exposed for my knot. (as long as haven't made skin incision too big cranially and avoid intra-op panting the clamp holds ovary out of abdomen nicely)

If I stab the vessel (I've done this before), I just continue and tie my knot as normal and then add a second encircling ligature on top. If I'm doing 2 ligatures, then I would tie the second one in same place as first (tissue is already well squashed there by first ligature, so if was any doubt second one should certainly be easily tied tight enough), perhaps ideally just below it.

This ligature preference reflects purely the way that I was shown in first week in practice by the other new grad who had learned how to spay a bitch from a book (Fossum I believe). Always interested in learning new ideas, but with no problems I'm aware of I'm hard pressed to change my habits. Still, had a perfectly competent boss who went 25 years before having a bitch spay bleed to death - uterine ligature had come off when was PM'd from memory.

My only objection to this technique is the extra time to thread some 6 metric catgut on to a needle (cut it at an angle to leave a sharp end); I do this while my clamp is in place to give it time to crush before moving it little nearer ovary before tie know in crush. (the single clamp technique - as I've said to students before: if you find one good clamp you like in a kit you may count yourself lucky)

RE: Double ligation

David Mills — Sat, 01 Dec 2018 22:44:13 GMT

[quote user="Anthony Dennison"]

[quote user="Clive Ansell"]Do they leave them all in situ, or remove all but the best one?[/quote]

Left all there. I cringed and told them it wasn't necessary.

[/quote]

They're normally pds or vicryl too, so take ages to be resorbed.

RE: Double ligation

Anthony Dennison — Sat, 01 Dec 2018 10:44:59 GMT

[quote user="Clive Ansell"]Do they leave them all in situ, or remove all but the best one?[/quote]

Left all there. I cringed and told them it wasn't necessary.

RE: Double ligation

Clive Ansell — Sat, 01 Dec 2018 10:14:42 GMT

[quote user="Anthony Dennison"]I've seen some new grads put 5 or 6 ligatures on a cervix before![/quote]

Really!?

Do they leave them all in situ, or remove all but the best one?

Are basic and elementary surgical principles and skills still being taught in the schools: ligature placement, suture materials, haemostasis, surgically relevant anatomy etc?

RE: Double ligation

Anthony Dennison — Fri, 30 Nov 2018 17:16:02 GMT

It's interesting to read this thread. I only use single ligatures, but I think I'm the only vet in my practice that does. I was beginning to think perhaps I was being inadequate.

[quote user="Evelyn Barbour-Hill"]On the other hand, it's always good to tie a ligature on a bit that's been previously crushed by a clamp that's been applied and then removed again..[/quote]

This is what I do - place a clamp, loosely put my first throw around the clamp then slip the clamp out after release and tie straight into the crush site. I've found loosely throwing over the clamp makes it less likely to catch anything else in the ligature and I can then tighten it one handed.

[quote user="Clive Ansell"]When folk place a ligature they are not entirely happy with, do they just place another in addition, or remove and replace the inadequate one?[/quote]

I'll often get rid of it and do it again. If it's tight on and there's a bit of oozing from the stump that's not stopping, I'll pop another on. I've seen some new grads put 5 or 6 ligatures on a cervix before!

One trick I was taught as a student was leave the ligature ends a little longer than you would normally do - makes it easier to find them when there is a bleed and you're fishing around for a stump.

RE: Double ligation

Clive Ansell — Tue, 27 Nov 2018 10:31:21 GMT

When folk place a ligature they are not entirely happy with, do they just place another in addition, or remove and replace the inadequate one?

I tend to remove a ligature I am not happy with; again I don't want any more or redundant foreign material than necessary remaining.

I sometimes place temporary ligatures. for example in season cat and bitch spey's where the uterus is friable I will place a temporary thick ligature in case in inadvertently cheese wire through the stump. Will then remove once I am happy with the ligature proper.

RE: Double ligation

Liz Barton — Tue, 27 Nov 2018 10:13:31 GMT

[quote user="David Mills"]A ligature is either good enough or not.[/quote]

You sound like Dick White... which is absolutely a compliment (saw him operate lots as an intern; he really was something else). He taught me how to do bitch spays, and was absolutely of the opinion that one ligature is sufficient; the important thing is to perfect doing them well. Why put in extra foreign material and create more devascularised tissue between your two ligatures?

FYI he also hated surgeons knots (2 throws then one), in favour of balanced knots; i.e. single throws, or to crush wide areas of tissue a double or triple throw followed by a second double or triple to make sure the knot was symmetrical.

RE: Double ligation

Tim Browning — Mon, 26 Nov 2018 15:20:56 GMT

I think you should modify technique for the fat stumps and you can usually single ligate a thin dog.

The anatomy is that the BV are going to a different place to the ligament, they diverge so this gets worse the lower down you get to achieve a good stump. I used a single ligature tight around the BV first by passing needle holder through the fat and then take a turn around the ligament. This won't bleed much anyway and once you have separated the BV and nailed them you can relax, its less likely to slip as well.

But if you can't relax do a second ligature, its not the end of the world but two bad ligatures around a massive stump without tying the BV separately may still fail.

RE: Double ligation

Elivet — Sun, 25 Nov 2018 11:28:20 GMT

I have not double ligated for the last 5 years since I discovered Miller's knot. I have not had any bleeding/slippage issues that I used to get with double ligations with surgeon's knots. I only ever use 2/0 Vicryl/surgicryl for all my ligations.

RE: Double ligation

Gillian Mostyn — Sun, 25 Nov 2018 07:49:46 GMT

I'm with David here. I intend to always place one ligature. I occasionally place two...but only if there is a good reason, such as the first one sitting itself too close to a clamp etc.

I actually don't understand the 'I place two for added security' argument. If you have been unable to tighten the first one adequately, for whatever reason, surely the answer is to adjust something else? For example, moving the ligature further away from a clamp, change the suture/gauge, improve exposure etc? I don't see why routinely putting a second one on would prevent bleeds. .

RE: Double ligation

David Mills — Sat, 24 Nov 2018 20:13:54 GMT

[quote user="Chris Milligan"]feel free to do some research and publish it then David. [/quote]

Why would I?

I can't remember the last time I double ligated a bitch ovarian pedicle (n>1000).

I don't see the need. A ligature is either good enough or not. I spent a lot of time early on in my career watching, taking advice, practising, and aiming to perfect this skill. I just assumed everyone did, and didn't leave redundant foreign material inside. I can't really see any reason for it.

RE: Double ligation

Chris Milligan — Sat, 24 Nov 2018 17:17:44 GMT

[quote user="David Mills"]A lot of "one knot good, two knots better" on this thread (without a scrap of scientific evidence)[/quote]

feel free to do some research and publish it then David.

RE: Double ligation

Evelyn Barbour-Hill — Sat, 24 Nov 2018 17:02:06 GMT

We've been here before, but to repeat;

don't tie a ligature close to a clamp. What you are ligaturing is approximately round in cross section. The clamp squashes it flat but when the clamp is removed it will try to go back to round and the ligature will loosen.

On the other hand, it's always good to tie a ligature on a bit that's been previously crushed by a clamp that's been applied and then removed again..

RE: Double ligation

Lindsey Edwards — Sat, 24 Nov 2018 13:05:25 GMT

Two perfect ligatures is overkill, two poorly tied ligatures life threatening...one adequate ligature sufficient.

I hope no surgeon intends to apply substandard knots but a fall back second ligature can't be a bad thing, I have never detected any issue from necrotic stumps. Was always taught not to tie one ligature over another as the irregular surface hinders good knot placement and you will deform tissue in opposite planes - remove carefully or tie proximally if you need to replace. I place two clamps below ovary and tie one on either side of the lower one especially in larger/overweight bitches

RE: Double ligation

Harriet Nicholson — Thu, 22 Nov 2018 08:54:08 GMT

I need to double ligate to sleep at night, although I'm sure my one ligature is enough I just can't do it - for me the sanity of knowing there are two is so important!

RE: Double ligation

Rob Loxley — Thu, 22 Nov 2018 08:49:44 GMT

[quote user="Clive Ansell"]What do folk do with large or thick cervical stumps, with pyometras or C-section spey's for example?. I tend to separately ligate vessels, sometimes an encircling one too, and usually oversew the end and omentalise. [/quote]

I've given up oversewing these thick stumps, haven't noticed any difference. Will often ligate each uterine vessel then single ligature on the stump.

[quote user="Evelyn Barbour-Hill"]

[quote user="jamie winstone"]Nobody ever means to put an inadequate tie [/quote]

No.... but sometimes people aren't very good at ligaturing

[/quote]

And some are not good at recognising that the knot is not good. When teaching knots (in other spheres, for climbing and lifting) I make sure people know what the correctly tied knot should and shouldn't look like. I'd suggest being critical of one's ligature skills is the best 'double-safe' system - if the knot doesn't look good or it bleeds then replace (or in surgery add another if more appropriate).

[quote user="Evelyn Barbour-Hill"]

[quote user="jamie winstone"] bleeding bitch speys are very common.[/quote]

[quote user="Anthony Todd"]of all the surgery we ever attempt haemorrhages after a B/S is the most likely disaster[/quote]

Are they? You rather surprise me.

[/quote]

And me too.

[quote user="Michael Woodhouse"]I cut it with scissors ~75% of the time. Makes it much easier[/quote]

Absolutely - if you improve the exposure it makes it easier to apply a good ligature and to check the ligature you've applied is correct

RE: Double ligation

Julie Innes — Thu, 22 Nov 2018 08:40:44 GMT

as Joyce said, my version is like hers, slightly different from the Miller knot after watching more closely!: Make loop first, pass both ends through, one end goes one way, one the other, beds ligature in, then both ends round other side and tie (I sometimes come back round and tie again at other side too!

RE: Double ligation

Joyce Whitehead — Wed, 21 Nov 2018 21:58:29 GMT

I generally single ligature, but them pass the end round before doing the second lot of knots which sort of double ligature. I’m not sure if what Julie is talking about is a Miller knot, I’ve seen those abs I do something different. I take the ligature, half it so you gave two free ends and a loop at the opposite end. Pass the loop round the area to be ligatured, then pass the loose ends through the loop. Pull tight, separate loose ends and it will lock, allowing you to knot without slippage.

I rarely break ovarian ligaments. I also never put forceps between ovary and body wall, I only place one pair between ovary and uterus. Gives you much more space and vision. Odd but it works for me.

RE: Double ligation

Michael Woodhouse — Wed, 21 Nov 2018 21:14:42 GMT

Millers, pass the free end under the complete loop. Catgut. Yes, see before. 3 or 4.