Computer generated transcript

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

I've got 28 people in so I feel like getting enough to start. Um Yeah. Um Hi guys, thanks for coming. Um I know this week's probably quite hectic for a lot of people, especially in like finals in case you've got like PSA S and finals coming up. Um But yeah, thanks for going. Um So my J I'm just the president of Liverpool's Anesthetic Society. Um and then Sam is gonna do talk today. He's currently working at the Royal Liverpool. Yeah, which is like the main, like big tertiary center in the center of Liverpool. So it sees quite a lot of like action and stuff. So it's one of like the main big hospitals and dual training and um anesthetics and ICM. So, yeah, take it away, Sam. Thank you very much. Yeah, so I'm Sam, you were um initially we, we've got regional anesthesia F po because er, Doctor Mahato is one of uh the pain consultants has a big interest in regional um sort of baggy this talk. Uh Well, well, not, unfortunately, fortunately very happily has, has had a baby a little bit early. So, um so I've stepped in to fill his big shoes. So thank you very much for spending your time on a Tuesday evening when you could be getting ready for PSA, I don't envy anyone, but we'll have a quick run through of principles of regional anesthesia if that's all right with everyone. Um So the, the reason the aims of the talk today basically are to, to talk about regional aesthetics from the ground up and give you some basic understanding for something that is, I think sometimes poorly understood. And I think even within anesthetics training, even amongst different consultants, I think it's something that, um, you can get a bit lost in the weeds about. And certainly as a medical student, if you, if you haven't got the basics and you're then looking at someone trying to fumble around with an ultrasound machine and a needle, not really knowing what the pictures showing, not really knowing what we're trying to do. Um, a lot of it, a lot of the nuance completely gets lost and it, and it can put people off and I think there's a lot to be learned and I think there's a lot of practical physiology and anatomy that gets missed if you, if you don't, if you're not able to engage with that process. Um, and it is a variably done process from place to place as well. So that kind of makes a little bit of difference. But I think the more you have a grounding of the the understanding of what's going on and the kind of the culture of it, um the better you can engage with that as a learning process. Um So we'll talk about some of the jargon and the culture around it. We'll talk a bit about the conduct of regional anesthesia um in general. And we'll talk about some of the more specific blocks. But again, this is a huge topic, you could talk about blocks for, for days. Um, and people do and there are, you know, huge areas of study dedicated to it as well. So to really go through, you know, blocks is an example of, of how you do blocks as opposed to, you know, these are things that you need to know. It's more of a tool to sort of talk about why it's interesting and, and what you can learn from it. And yeah, and just basically equip you to make the most of your learning experiences when you're in theater and read your anesthesia is going on that, you know, better, better get something out of it. Um, I don't feel like there's need saying, I feel like, um, you probably can't fart at med school at the moment without having done it on a simulator before. But, um, I'm not saying you should go out and have a go, you know, I'm not endorsing, um sticking some local and some places again, I II feel like you probably will know that, but just in case it comes back to me. So we'll, um, we'll consider some definitions of regional anesthesia, some technicalities about it. We'll talk about how we can use it and you know, what circumstances do we use it in. Um, we'll talk about what we like about it and you know why we, why we think it's a good thing and we'll talk about why we might not and some of the, the downsides to it, um, we'll talk about the conduct of those sort of the nuts and bolts of the what wear and how big emphasis on safety. Um And we'll talk a little bit about ultrasound. Again, ultrasound is something that'll probably come up and down in lots of different areas you're teaching nowadays. But, um, you know, a good understanding of ultrasound nowadays is, is, is really important for regional anesthesia. Um And then we'll talk about the, the plan A blocks. Um And we will look at some sort of specific examples from the plan A box as well. If you've got time by all means, if you run out of interest, it's getting late in the day, feel free to um, not stay for whatever you need to. But, um, that's the plan. So what is reasonable anesthesia? Really? Broadly, we're put in local anesthetic near nerves to stop their function. Um And that's, that's, you know, meaningfully ob obtuse like it's, I've made it very vague on purpose because really it does cover quite a lot of different things. And sometimes people talk about anesthesia and mean different things. So the, we'll, we'll dive into it a little bit more. There are different names, um and different techniques depending on what part of the nervous pathway you're actually trying to get to whether you're getting closer to the brain or whether you're getting further away from the brain and those, you know, those sort of nuances are still a little bit muddy, the further on you go. Anyway, one thing that's definitely useful to have in your head is the idea of an anesthesia versus analgesia. So we'll often talk about regional regional anesthesia. And that's kind of the blanket term for all of that, putting local to turn off nerves, regional anesthesia in its true sense means being able to achieve absence of sensation and specifically to be able to then perform an operation on that area. Um I'm, that's pretty uncommon, you know, it certainly happens, but um it's pretty uncommon to have, you know, a nerve block, for example, to, to do an operation by itself. Um The vast majority of when we talk about regional anesthesia will be for perioperative analgesia. So perioperative pain relief to sort of help reduce the amount of other things that you might give for pain. Um We usually call it regional anesthesia either way, whether you're doing it for anesthetic intent or for analgesic intent. Um But it's so useful to have that in mind. Um, and obviously we're talking about sensation but it's, it's really important to remember that depending on the anatomy of where you're blocking, you can, you can definitely cause a motor block so you can stop er, muscle power. Um, and you can cause autonomic dysfunction as well. So, um sometimes that's useful, sometimes that's uh a problem that needs to be either mitigated or, you know, counseled against when you're speaking to your patients, at least. So we talked about the different names for different, depending on where in that sort of chain of the neural network you are. So if we sort of talk more central, um you know, broader cover neuraxial, then that's, we'll talk about that in a second. But that's basically anything to do with the spine, spinal cord or spinal nerves. And then as you move more local, er more localized so out to the peripheries, you've got plain and field blocks, um you've got specific individual nerve blocks and then local infiltration and so we'll impact them a little bit. So, neo axial anesthesia, um sometimes called central nervous, er, central nervous system. Er, an anesthesia, um essentially is local anesthetic in or around the spine. And again, we broadly split that up into spinal or epidural. Now, we don't wanna go, we don't need to go into too much around spinal epidural. I know that there's a talk on obstetric anesthetics and that, that comes up a lot in obstetrics the, for anesthetics, at least the, the use of the spinal or epidural. But basically the shortened version is a spinal. You are putting a needle between the bones and the back into, er, inside the jaw, into the CSF and you're putting local anesthetic there and then the needle comes out and that's the end of that, the anesthetic is delivered. You let it cook and see what happens. Um, an epidural is different in that you get to just outside the JRA and then you either inject local anesthetic there or leave a catheter there and continue to inject local anesthetic into that space. And that space is in communication with and that's where the er dorsal root nerves live. So the sensory nerves that come out from the spinal cord or live in the epidural epidural space. And so you put local anesthetic there, you put those nerves. So this is the, the diagram you put, you know, you block here, essentially, you block everything below that level. Um And certainly for a spinal, that's, that's the case really, you, you um you put low aesthetic there and at that level, everything below no longer is able to, you know, get information from below that point. And so you really do just turn off the lower half of the body with the spinal. Um, an epidural is slightly more focused um and can be slightly more titrable because you can put it into a, you know, a space and you can put that epidural at different levels. And therefore you can kind of depending on how much volume you put into that space, you can make that epidural push up higher or lower. Um, and therefore you can block more areas and obviously, depending on where in the spine you put it, you can block different um, nerves and so you can be a little bit more focused and you can titrate it a little bit more as opposed to a spinal where once you've put in the drug, you can't take it back. That's that. And if you put in too much, then you just have to deal with the consequences. Um, whereas if you're, you know, you're concerned about how a, a reason aesthetic is gonna go, an epidural is a much more safer, stable way to build things up. Having said that it is usually less dense or less reliably dense because, you know, the epidural space is not a uniform space and getting drugs or getting any fluid into all of that space predictably can be difficult. Whereas the CSF is a nice clean, continuous space, um, with nothing in it really other than nerves. And so once you've, um, once you've got local anesthetic into the CSF, which is water, the very lipophilic local, ahe, he just wants to go to the spinal cord. So you can use very small doses, get straight to the spinal cord and he works very quickly because of its risk profile, it is kind of treated as, as a separate entity. Um So, you know, it's very, very close to the spine. So there are the complications that would be pretty trivial if they happened in the rest of the body, if they happen in a very closed space with the spine, spinal cord next to it, that could be potentially catastrophic. So, infection bleeding, things like that plane blocks uh or, or field blocks are essentially putting local anesthetic into a tissue plane that, you know, nerves run through. Um And I say no, because a lot of the time you, there's anatomical variants and there's too small for you to really be able to see. But you, you know, from enough anatomy studies that that's where they should run through and you're putting local anesthetic into that area to then turn off the nerve. So the examples we've got are um transversus abdominis um or tap in the transverse abdominis plane, rectus sheath, which is um the muscles in the, the sheath that cover your rectus abdominis muscles, um or the ecto spna plane, which we'll talk about a little bit later as well. Um So to sort of visualize it, if you put local anesthetic into these two sheaths and the, these sheaths are the fibrous sheaths that surround the rectus abdominis muscles in the center, then you, you know that if you put local anesthetic into that space, the local anesthetic will bathe the nerves that run through that space with local anesthetic. And so distal to that ie in the midline cos they all, they all come around the outside during the middle, they all get numb. And that's very useful. If you're doing a laparotomy where you can make, making a big cut in the center of the abdomen, you've numbed up that area. So that's a very commonly used one. And so you get that nice patch distal to the nerves that you've just bathed. Um So we often when people are coming up with these blocks, they determine them by cadaveric studies. So they'll inject blue dye into a tissue plane, you know, replicating what you do with the block and then they open up the tissue afterwards and perform a a prosection and find where the blue dye has gone and therefore work out where you would be covering with local anesthetic. Um And so that's how these sort of mm these blocks are studied. Um Because often the, the nerves are too small for you to see on an ultrasound and they have so much anatomical variant that you couldn't really reliably block them every time. Um So they're useful for covering a large operative space in cases where nerves are too small to see. But because you're kind of shooting blind and you're aiming to fill a space, you do need a large volume of anesthetic, which potentially has implications. You know, if you're trying to cover you, you're just trying to get it everywhere, you need more volume. And so that increases the amount of anesthetic that you're actually giving to a patient. Um So peripheral nerve blocks, this is essentially you can do this for any nerve realistically that you can think of or potentially access. Um Obviously, some are more useful than others. Looking at the humble ulnar nerve, you put local anesthetic around the ulnar nerve at the wrist, for example, then distal to that, you'll get anesthesia and you know, I'm sure the nerve fans in the audience will know about the sort of sensation distribution to that. Um you know, ring and middle finger, sorry, ring and little finger. Um and sort of as well the motor component of that. So you will get ulnar distribution of weakness. Um So it's targeted local anesthetic. You, you need a small volume because you, you can get the local anesthetic right next to the nerve, which is useful. Um and it will only affect that nerve. So it doesn't spread anywhere else and it will only affect that nerve and it's distal branches. So you can be a little bit more selective about where in that nerves course you put the local anesthetic, which means that if you, if there's a, for example, for the femoral nerve, if you block the femoral nerve quite high in the thigh, in the femoral triangle, um you'll block the sensation in the femoral distribution, but you'll also block, um, all the muscles that control the thigh. Uh, and if you're trying to get someone home the same day, if they can't use their quadriceps, then that's challenging. Er, whereas if you block it in the adductor canal, which is sort of mid thigh, still following the femoral artery, but the femoral nerve in the a ductal canal has the, the branch for vast's media, for example, is already branched off. And so you can be much more selective with the sensory component. Um There is a risk of injury and compression cos you're getting right next to the nerve, you could poke it with a needle or you could put local anesthetic around it and the nerves don't like getting squashed basically. And often when they're in the distal, you know, lens, for example, they're in quite tight spaces and lots of other things around them and they can get squashed. And then finally, we've got local infiltration, which is, you know what you'll see quite a lot of and many of you will have sign offs for injecting local anesthetic. You're just putting it into the tissue to get right to the end of the um nerves and it just blocks where the local anesthetic is. It just blocks this tissue that it's affecting. Um You can use a very small volume depending on what you want to cover. But obviously, if you're covering a large area, you might be using quite a lot of volume. Um You can be very selective of where you're putting the, um the local, assessing where the effect is happening, but it tends not to be especially dense. So you can run into trouble with, you know, patients having procedures on the local and starting to feel like they can feel things and, and getting upset about that, which is understandable. Um, but it is usually very low risk cos you're basically putting it in innocuous tissue, um with minimal vascular supply and usually small amounts. So that's, that's one of its positives. Um, there's a couple of miscellaneous ones, the beer block, which I don't know if anyone's heard of or seen, they're a bit, a bit hairy to watch, in my opinion, it's essentially, um, procedure that was used quite a lot in A&E particularly for collies fractures or distal radial fractures. Um, and essentially you put a large tourniquet on the arm. Um, you have to block arterial and venous flow, er, and with a cannula already already in the hand, you, you then, um, fill the arm with local anesthetic. So you IV inject local anesthetic into the, to the limb. Um, and that then over 15 minutes will, you know, induce anesthesia everywhere the, the light touches as well. The obvious complication is that if your tourniquet fails, you've got a large volume of local anesthetic that's been directly injected into the venous system. Um And so you can end up with problems from that. Also, you can't block the tourniquet pain and it is quite painful to have a, you know, a tourniquet at 250 millimeters of mercury for 20 minutes. Um So that's, you know, that's in itself a pain. And sometimes depending on the vascular access, the vascular sort of lay out, you can get quite patchy blocks, but it's fun to see. Uh and then a ring block is essentially like a nerve block all the way around a structure. Um And that's kind of just subdermal local anesthetic infiltration to try and get any nerves that might be going past that point. Er So obviously, fingers, you could use it for um ankle block is a kind of, you know, you, you get five nerves, but you're kind of using a ring block to do it. Um and likewise a scalp block as well. You could consider a big ring block. It's not always very effective, although it is usually pretty simple to do. So, when do we use, how can we use regional anesthesia? Obviously, as, as an anesthetist, we use it primarily in the perioperative period and like we talked about, that's either as a sole anesthetic technique. So you're um trying to give someone the conditions that they could have an operation without giving them a G A. Um And that's particularly useful for patients that are, you know, not gonna tolerate a G A very well or the small day case procedures where actually it would be a lot quicker just to, instead of getting them off asleep, getting them awake again, it would be a lot quicker to just get them nice and numb and then send them straight home pretty much. Um, it can be used as a perioperative analgesic strategy. And again, that's, that's mainly where we would use it. Um, and that's to give you pain relief, intraoperatively and postoperatively um trauma. So increasingly you, you may well have seen um in A&E s the use of er fascia, iliaca blocks, that's a, a plain block, um fascial iliaca blocks to block pain from er, a fractured neck of femur. Um and that's something that's now well documented as a landmark technique so called pop pop technique where you feel the pop going through two fascia um and also as an ultrasound technique as well. And that's pretty much, you know, considered gold standard for fractured neck of femur that aren't gonna be operated on within 12 hours. Cos it provides really good analgesia in a group of patients that do really badly having um pain and opioids. Um and likewise rib fractures. So, again, increasing severity of uh rib fractures on the background of, for example, CO PD, um they are sit and ducks for chest infections and so good analgesia allowing them to cough and to deep breathe is really important. Uh And now things like um ecto spinal blocks and catheters are being offered as a means to provide analgesia without knocking the patient out with opioids. Um So you may well see both of these in practice in A&E even if you're not on anesthetics. Um and then there's the big sort of pain, you know, specialty as it were. So, pain medicine is uh is becoming a big specialty and is, you know, certainly traditionally in the UK, staffed by anesthetists, you know, as well as the multi team. Um And so there's a lot of interventions that are used for chronic pain as a, as a tool to sort of move forward with improving the pain or as a long term, you know, treatment, a repeated treatment for pain. And there are again, very similar procedures. You're, you're blocking nerves to painful joints, for example, um cancer pain, again, if we know that patients have um non operable or non treatable cancers that are causing significant pain, there are some quite specific regional techniques that can be used to sort of treat them or, or in some cases really kill the nerves and neurolytic agents. Um autonomic symptoms, which can be a big problem for, for chronic pain patients. So, um chronic regional pain syndrome, we know that a big part of, of that pathology and and then, and its symptoms are autonomic disturbance. And so you can use techniques to, to selectively block the autonomic ganglia. And then the biggest, probably the biggest place that you'll see regional anesthesia, um, is labor analgesia. Er, and that's, you know, epidurals on a labor ward basically. And it's a very effective, um, and very well used um, treatment. So why do we like regional anesthesia? Um, well, there's lots, there's lots to like. So the patients, you know, I suppose the most obvious benefit is if it works well, they get good pain relief, um, which, you know, sounds, sounds obvious. Um, but it needs to be also caveat by the fact that we don't need to give them as much other things. And so while you can probably get people, you can get patients through any operation with enough morphine, ketamine, cloNIDine, paracetamol or, you know, all the other tricks in the bag, they all come with side effects and they all make people feel nauseated or spaced out or stop them breathing or make them start to wake up. And so the less exposure to other nasty drugs you can get the better. Um And so that's, that's one of the biggest benefits from that. Uh And some patients just really, really, really struggle, but some operations though people really just struggle without having some sort of regional anesthetic thing. Um there's good evidence that it reduces the risk of chronic pain disorders. So, um again, going back to your pain physiology, you've got a painful sensation, it travels up your sensory nerves, it travels up to your spinal cord and it travels to your um sensory cortex and that's kind of the basics. But alongside that, there's all the modulating um neurons. So there's the um descending inhibitory neurons, there's the local feedback loops in the spinal level. There's the local cytokine um exposure, which then has the systemic cytokine exposure and you get sympathetic responses. So it's a very, very complicated pathway and if you have extreme pain, um and you're kind of neurologically primed as well, I suppose you're at risk of having chronic pain after um an operation and you know, persistent postoperative pain can lead to chronic pain. Um And there's good evidence that if you have good regional anesthesia and you stop those neurons from, from activating in the first place, then your risk of having long term chronic pain disorders is lower. Um And then if they can get away without having a G A or having a lighter G A, then everyone feels better, they feel less sick, blah, blah, blah. Um We like it because II put satisfaction in mastery first because I think it really is um it doesn't seem very patient focused, but it is really quite important. You, you've got to do a job for, you know, th you guys have been doing the job for 40 years plus probably um and you need to have something that you really enjoy about it. Otherwise whatever you do it will become um it will become monotonous and it will become difficult to continue. And I think for some for some people, for some of these cysts. And again, this is by no means everyone, for some of these cysts, regional anesthesia really does provide satisfaction and mastery. Um If you have seen a patient who you've given a block to wake up in complete comfort and you've not had to give them any morphine. And you, you know, you've watched their BP stay completely stable throughout. It is really satisfying to see that and that, you know, learning new techniques and trying new techniques and, and just the little marginal gains every, every week for a regular list, for example, can really be satisfying. And so some of you in the audience are probably going, that sounds terrible. And that's, that's fair enough. Even not all anesthetists enjoy regional. Um but it is probably a big factor, you know, we're the ones that keep it going cos the surgeons sure don't want it. Um It does give you a lot better hemodynamic stability during an operation. So if you're um constantly trying to give them more medication to control their BP because every time they do something painful, the BP spikes and then you end up giving them more, you know, anesthetic or more um analgesia, then you're just constantly battling and, and you end up with more side effects later down the line. Whereas if you're giving someone a block and they, they don't feel it, then they don't have any other systemic sort of symptoms of pain or signs of pain afterwards. Um, the biggest reason that anis get complaints and litigation is pain and nausea. Um, and a block is good for both of them. If you, if you get a good block, you've got good pain control. So they don't get pain and then they don't need nausea, which is usually the thing that, uh, sorry, they don't get morphine, which is usually the thing that makes them nausea. So you don't get complaints about that. Um, and if you don't have to give a g, a great the surgeons um, slightly glibly, I put something to attribute delays to. And again, I'm, I'm not, uh, I'm not trying to tar surgeons with the same brush and I appreciate they're a hetero heterogeneous group, but some surgeons really do not believe in regional anesthesia and, er, do consider it a waste of time and I think, er, sometimes, maybe they're right. Um, you know, it really does depend on the case but there's a lot of cases and a lot of good evidence for the use of regional anesthesia. Um, but it is, it is a timely, you know, it is a time costing thing. Um, but the, you know, patients are more comfortable and they're not sick, then the surgeons also get less complaining afterwards. Um, and there certainly are some procedures that because of the sort of autonomic changes that happen regional se there's better operating conditions regarding bleeding if you've had a block. So just say that next time a surgeon surgery day, a woman, um and then from the NHS, from a sys systemic point of view, you know, you don't have to give a G A or opioid. And so therefore they're less likely to need uh antiemetics, they're less likely to stay longer until they can eat a drink. Um And therefore you reduce bed hours and that's what the NHS cares about basically. And again, fewer complaints always better. So then why don't we do it for everyone? So we talked about time. Um I said, should that matter? It, it obviously does, you know if you that balance of, you wanna do the best for every patient, but you also have to do the best for every patient. Um And so it may not be necessary or in everyone's best interest for you to do a block for every case. But you know, there are definitely cases where taking the time to get their analgesia right before you've done anything is, is 100% the right thing to do. And so he knows in circumstances, taking the time is, yeah, it doesn't matter. Um But there are complications from regional anesthesia. Um some of which we kind of talked about so local anesthetic toxicity or intravascular injection. Um Again, we'll talk about that in, in this, in more detail, in a bit, but obviously a big problem. Um nerve damage either from you poking them or squashing them with uric anesthetic or bleeding, um, unpleasant sensations. So, when people wake up and they can't feel that, you know, their arm that now has 10 screws in it, sometimes people find that more unpleasant than, or they say they found that more unpleasant than having the pain. And I don't know, I don't know how much you, you could really put to that unless you've had that exact experience. But, um, you know, you, it's probably sensible to counsel patients that it can be unpleasant to not be able to feel your hand or to have pins and needles or to have other, just strange sensations to the area that you've blocked. And so, you know, they may, if you don't tell them about it and they experience it, then they may complain. Um, some of the surgeons are concerned about it causing lack of sensation of pain as a warning sign. So, obviously, pain is, is physiologically and er, evolutionarily designed to tell the body that something's happening. Um, and for example, if you just operated a complex vascular procedure on somebody's lower limb, there's a risk of compartment syndrome, which is, you know, er, an surgical emergency. And the cardinal feature of compartment syndrome is disproportionate pain. Er, and if you've anesthetized that leg and they can't feel the pain, then that, that compartment syndrome may present much later to the surgeon causing more damage. Again, it's usually, that's usually quite a rare circumstance and it tends to be trauma, orthopedics, vascular. Um, but, you know, at the end of the day it's the surgeons that have got to deal with that complication. If they, if they find that risk too, too unacceptable, then that's, that's, that's on them, I suppose. Um, infection, you know, anything where you put a needle under the skin, you can risk infection. Obviously, it's a bit of a spectrum. If you're just doing a peripheral nerve block, the needle goes in, the needle comes out. It's not really that much different from a cannula. Again, we talked about putting a needle near the spinal cord infection. There is obviously potentially catastrophic. So big spectrum actually very, very rare, usually um autonomic disturbance. So the biggest one tends to be if you're doing um anything that your spinal nerves, thoracic spinal nerves particularly or a spinal anesthesia, they will knock out um the autonomic, the sympathetic chain. So you can end up with hypertension, you can end up with bradycardia, which you might need to do something about if if not at least counsel the patient about um and then damaging local structures. So, you know, obviously that this depends on where you are. Um if you're doing a block in the neck, which is not uncommon, then there's obviously quite a lot of very important structures that you would like to not hit with your needle. Um trachea, vertebral arteries, carotid arteries, um lung So, um thinking about what you might hit does change how you co the patient and just change the risk profile. So we'll move on to the sort of conduct of regional anesthesia. Talk about safety, sort of running throughout it, talk about what we use where we should do it and, and then how we physically do it. So, um kick Festival, we love kit um all in the UK, all regional anesthesia should be done using what's, what's called Nr Fit, which is stands for Neur ax neuraxial and regional anesthesia. Fit needles and equipment. So all the yellow stuff means that this will, this will only connect with other Nr Fit equipment. Um which importantly means you can't attach this syringe to a standard lower lox syringe. So you can't inject your local anesthetic therapy into someone's vein and you can't pick up the, I don't know antibiotics that you've drawn up to inject straight into the epidural. Um And so that's, you know, a safety feature that's now sort of nationwide pretty much um much the same as the NG anything feeding tubes. Um you know, ginos, um gastrostomies, NG tubes should all have the purple kits. You have a purple syringe, you have a purple lock. It means you can't put somebody's TPN into their, well, no, no, I'm talking about you can't put somebody's er NG feed into their central line, for example. So within that, we've got obviously syringes for drawing stuff up this is a blocking needle. Um Some of the interesting features are again, nr fit nice long tubing so you can put the needle where you want it without it being dragged around by the syringe. And then it's got this section which is for a nerve stimulator. So you touch that to a nerve stimulator. We'll talk about that in a minute and then the needle itself. So it's got um markers on it. So you can see how far down you are. And although you can't see it here, it's, it's ridged. So it's got a, a microtexture to it, which means that when you're ultrasounding it, you can see it more easily. Basically it of sparkles a little bit on the ultrasound. Um This is a Tuohy needle which is a big needle um that you're able to pass a catheter in. So we use these, this is standard practice for an epidural. Um But you can use it for inserting any catheter and nerve catheter. Key features of this are, it's big, it's rigid, so you can get good feeling of the tissues that you're poking through, but you can also poke through some tissues. Um And it's got a kind of bladed but curved um tip and the, the whole, the bevel is actually uh at the side of the tip, which means that, um again, it adds to that feeling as you're going through the texture. So through the tissues, but it also means you can direct the catheter a little bit. So you can usually you thread an epidural upwards, you know, from, from where you put it going up. But likewise, you could um pass a catheter one way or the other. Um And if you're doing the nerve, a nerve uh catheter, then that can be quite useful. And then this is your standard kit for an epidural. As you got two, you've got the epidural C which is very, very thin, special dressing. Bye bye bye. So for the kit that we use ultrasound, so again, we'll, we'll talk about, about ultrasound in a little bit in a minute, but again, very good. Well, completely revolutionized regional anesthesia really and, and a lot of anesthetic practice, actually, um I'm sure it's becoming more prevalent in medical school training. We didn't really have anything at all, but you'll, you will see more and more IV access with an ultrasound and you know, point of care ultrasound testing. So it's gonna become more and more useful, but it definitely is a, again, changes for anesthetics. Um This is a nerve stimulator. So essentially you stick, the needle is attached to a wire and you stick the wire in here and you put a pulse of a certain amplitude of current and a certain frequency and you can, as you get closer to the nerve, it will cause a nervous impulse. Um and you can, you need a, a nerve that's gonna have a motor component. Um And you can see whether you're at the right nerve depending on what muscles move. So it tells you that you get into the right nerve. But also if you turn the amplitude low enough, it tells you if you're too close to the nerve. So if you've got your amplitude at 0.2 milliamps, which is, you know, a tiny, tiny current and you're still getting some twitches of that muscle group, then that tells you you're pretty much in the nerve, in which case, you should come back before you inject because you might push apart the nerve with your injection. Um And then this is a pressure monitor. So it's a similar thing for a similar sort of um reason. It's, it tells you how much pressure you're applying to the to the local anesthetic as it's going into the tissue. And again, the same thing, if your pressure goes up too high, that might be a suggestion that you are um in the in the sheath of the nerve. And therefore, you know, much, much more likely to cause uh iatrogenic nerve injury than if your pressure is nice and low afterwards, you know, outside that nerve. So obviously, we need to use some drugs. Um local anesthetic, pretty much I is always gonna be in a block. You can do spinals with just diamorphine, for example, but most of the time you'll put some local. So the ones that you will see are obviously lidocaine, which comes in one and 2%. Um, bupivacaine and levobupivacaine. And you might see ropivacaine. Um, there are shorter acting, local ace that you can use for shorter spinals and things like that. But these are the ones that you, these three, to be honest are the ones you're gonna be able to see. So lidocaine, um very good, nice and safe. Um, for the most part, it's quick acting but will last less time. Um, compared to bupivacaine and levobupivacaine, which both have much longer durations of action, but do tend to come on a bit slower. So you, you couldn't less useful in A&E for example, but, um, more useful for surgery, um, you can add other things to your mix as well. So you can either add something that's gonna directly cause, you know, a better block, directly acting agents like, um, opioids, fentaNYL and diamorphine are both, er, you know, regularly used in spinal or other nerve blocks. Uh, and likewise cloNIDine ketamine, which are both, um, sort of non opioid analgesias, non opioid painkillers. Um, and they can, they have central acting features. So then they're good for either spinals or epidurals as well. And then dexamethasone, which is a corticosteroid, um, has a good, uh, a good use at lengthening the, the time that a block will last for. And then you can use ones that are not sort of nervous acting medications. So, adrenaline, you'll often see adrenaline used with lidocaine, for example, where it's um you put it into the tissues, it causes local vasoconstriction, which means that less of the anesthetic is absorbed away. But also, um if you go about to cut that area, the vasoconstriction means that bleeding is less as well. So that's a common mixture. And then sodium bicarb theoretically changing the tissue ph to more alkali is helpful at um speed of onset of, of action of local anesthetics. But in practice, it's not that often done. Obviously monitoring, you need to be in a monitored area with heart rate cycle and BP, um, sats as well as um, ECG and respirate. Um, and then sedatives. So you can obviously use sed sedation to, to go along with your block. Um, it can help smooth out a patchy block, um or the other sort of unpleasant sensations, but it obviously does expose you to other medications which can cause problems. Um, where should you be doing this? Well, it's a, it's a dynamic risk assessment. Basically theater is obviously the safest place to do a block but not always practical or available. Um, so you can do something like it's an ed um, recovery. Certainly, er, on the ward in an outpatient treatment room. I think some ambulance crews particularly, you know, er, prehospital medics will, will use it on scene for, for pain relief, for transfer of trauma. Um, you just need to think about what your monitoring capabilities are and what the clinical oversight of that block is like, who's gonna be able to watch them after they've had that block. Um It needs to be clean, like at the very least clean, if not sterile. Um And so sometimes doing uh fas iliaca block on the side of the road isn't the best thing for the patient. Actually, if you're gonna get some grit in your groin. Um And obviously you need to think about local anesthetic toxicity and where your la toxicity kit is, which we talk about now. Um So local anesthetic toxicity, thankfully, very rare really. Um but obviously a big problem if it does happen. Um It's a multisystem disorder. It does really have a spectrum presentation. It can either present immediately if you accidentally get something into a vein and you inject, then that will present pretty quickly or late. If you've just injected a large volume into a sort of um a plane and that slowly gets absorbed over time and eventually reaches a peak concentration that is toxic, then it can present much later, sort of hours after potentially. Um So in terms of what it does C NS is the most common presentation really and that tends to be agitation or confusion. You get the cic tinnitus or um perioral tingling that they might describe if you've injected it into a vein and it was a big dose. The main thing that you'll see is they'll have a seizure um but you can do with coma as well. It is a respiratory depressant and causes respiratory arrest and then from a cardiovascular point of view, you'll tend to see hypotension and um gray dysrhythmias, but you can pretty much get anything so they can get tachy arrhythmias, they can get ST segment changes, they can get genuine ischemia and you can have cardiac arrest, you know, basically study as well. Um Treatment is, you know, for the most part supportive ABCD E um you know, you should be doing in this place where you can deliver critical care. Um And uh there is a specific treatment which is intralipid. So it's a high concentration lipid emulsion. Um and the idea is that because local anesthetics, so lipophilic, when you put all these fat globules into the system, it will chelate them. So it'll absorb all the local anesthetic er and prevent them from getting to your brain and heart, which is the main thing. Uh So there's a weight based dose regime and the the it's important to know, you know, particularly if you're doing a lot of blocks and high risk blocks where the intralipid is and the sort of protocol for how to get it. Um So how, so, you know, again, this isn't, this isn't how to do a specific block. This is just a general how you go about it from a, from a start to finish type type of thing. Um Consent is obviously a big thing and it depends on where you are, what trust you're in and, and what kind of the risks are, what block you're doing. But verbal is often adequate. So verbal consent is often fine for spinals and epidurals because there is a different risk profile. Lots of trustable mandate written, um a written consent as well. Um You know, get your set up so you wanna be getting your monitoring on, you wanna position your patient, you wanna position yourself, position your ultrasound. So it's nice and lined up so you can see what you're doing and it's the best block is the one that you can do most comfortably. Um And make sure they've got good IV access if you're doing something risky anyway, um sterility. So if you're doing a nice big flat piece of skin that you can clean well and is a nice peripheral nerve, then you don't necessarily need sterility. You know, asepsis is, is fine. Um If you're doing something particularly where you're gonna leave a catheter or you're going to do a spine or an epidural, then really of surgical asepsis is, is what you should be aiming for. Surgical surgical il is what you should be aiming for. Um and then stop prep block. So you may well have heard of all these um this is association, an initiative um and it's to prevent wrong sided surgery mainly, but it is a good way to just make sure you know what you're doing before you embark on something in a stressful environment. Um And the idea is that before you do anything, you check the consent form with the patient if you can and they're awake, check their identity and check the site of surgery marking. And so that, you know, you're not gonna block the wrong side because it happens. And then also if you've blocked the wrong side and then the ODP exposes that side as they take them into theater, then there's a, a reasonable chance that the surgeon may then well operate on that side. Um And so that's how never events happen. And you can all have a look at the many, many never events that the NHS has outlined. Um So next, you find your anatomy and that might be bony landmarks that might be using an ultrasound. Um and then get your needle into the right place. And so, you know, you're looking for where it is on the ultrasound, you're looking for a bony backstop. If you're, you know, you're trying to hit something bony and you might be looking for your nerve stimulator to check that correct muscle group. Um, aspirate before you inject is very important. You don't want to be in a vessel. If you're in a vessel and you get blood back, then, you know, you want to inject blah, blah, blah. And then when you're happy, you inject you like an an. So you're looking for feedback and that's feedback that you might feel at the end of the syringe. If it feels very tight, then that's probably a sign that you're up against something you shouldn't be. Look at your pressure monitor, look at your ultrasound screen and see where the local anesthetic is going. That's one of the best things about ultrasound is you can see whether you're close enough and whether your, the local anesthetic is getting where you want it to go. Some things to consider. So risks something is risk free region. Anesthesia can often be done. Yeah. So regional anesthesia can, when it's used for analgesia, it can just be completely avoided and then you've got rid of all those risks, it might expose you to other things. But you know, you really have to counsel these patients carefully about the risks. Um And that is obviously the, the risks are different depending on what type of block you're doing. Um and then bleeding and anticoagulation. So, catastrophic bleeding is very rare from a uh a block. You know, unless you're up against the intercostal artery, for example, when you bleed into the chest, otherwise you're never gonna lose enough blood to cause a catastrophic bleeding. Um but you might compress something important in the neck or in a a small bony structure, you might compress the spinal cord. So you need to know what their anticoagulations are. Uh you need to know what their cutting screen is and the a GBI do have guidance about your actual, um, targets as well. Um, and then obviously afterwards, think about where they're gonna go, think about, um, how are they gonna be monitored for that period of time. Should you test the block? Yes. You know, certainly if you're gonna be doing it completely awake, but the surgeon should be testing before they start stabbing. Um, and then think about other analgesia that you're gonna be needing to give them as well after the block wears off or to compensate for your inadequate block. Um So ultrasound, like I said, very useful um allows much smaller volumes to be delivered. Cos you can get right next to the nerve, which is good for less systemic absorption. And it also allows you to see the tissue planes, any blood vessels, any visceral organs or bones. Um Sometimes you can see the nerves but it can be a bit tricky. Um You can use it for spinal so you can see you in spinal ligaments, for example. Er, and most importantly, you can see where your needle is and where your local anesthetic is going. Um So again, very briefly look on er, sorry, ultrasound, you know, things that you can see so big big circles that are black, these are usually arteries and you should avoid them if you can um nice er sort of bright white bone with a shadow underneath it. So that's the first rib. Um and then you can see this sort of gray speckling stuff is um muscle and then you've kind of just got fatty, you know, or nonspecific tissue all around. Um This is a brachial plexus um scan. So you can see this sort of bundle here is all the brachial plexus nerves and this is probably uh I don't know, supra or infra box. So you can see the um subclavian artery here. So the nerves look, I mean, they look great here. You can see nice sort of bubbles. They, they look quite dark and black. So you might be forgiven for mis mistaken them for, for example, uh you know, a vascular structure. Um but one thing that nerves do is they display an isotropy. So that is the the phenomenon where they look different depending on the angle that you're scanning them at. So this is this is a very exaggerated case. But um you can see this is the same anatomical setting scanned at a slightly different angles to be 81 degrees, 84 degrees, 8790. And if you get them bang on 90 then they often look fantastic and you can see them a mile off. But if you just tilt a little bit, if you tell about 8784 they start to become much more similar to the surrounding tissues. And so basically, that can just make it very difficult to spot nerves when you're ultrasounding them, especially if you're trying to get a good image, so we'll move on to some of the bit more clinical bits. I know we're getting tight for time. So we'll we'll um pass through some, so plan a blocks. This is definitely something that I suppose if you're interested in aesthetics, this is a really good place to start. I've got the QR code for the um for the RCO A S leaflet on plan A blocks and that's actually a really good document cos it does take cover pretty much everything in, in terms of the basics. Um So it's developed by re Regional Anesthesia UK, which is sort of like a AAA separate postgraduate group for to, to, to support regional anesthesia. Er, and they, they identified in like a an editorial seven blocks that all anesthetists should learn. Um and they were picked for their utility that they were well established and well documented and, and in most cases for their safety as well. Um and they kind of, you know, outlined this two tier system where every Anestis should be able to do these seven and some other ones probably, but the, the non regional experts, you know, should be able to do these seven and then some of the regional experts who do a lot of trauma, a lot of orthopedics might know some more specific blocks for their specific area and can support with other other blocks if needed. But these seven are a good place to cover most things. Um, so as you can see, we've got a bit of upper limb, we've got a bit of chest, we've got a bit of abdomen and we've got a bit of lower limb. So it kind of covers the good selection. So we'll talk about a couple of them. So the brachial plexus is, sadly, if you, if you guys are interested in anesthesia, which I suppose if you hear you, are, you, you're gonna get asked about the brachial plexus and they're gonna ask you over and over again cos they, it's anatomy that is um very testable. So, and it is, it is sadly important. So it, it does have some me learning. Um but essentially brachial plexus is a, a big plexus of nerves that travels from the neck to innervate your upper limb. Um And you know, these are the, some of the confusion of it C five to T one. It's the output from those spinal nerves. Um And it's sort of anatomically loosely divided into the spinal nerve roots, um trunks, divisions causing branches and kind of where you target will have an effect on how the anesthesia comes out. Um So this is what it looks like kind of in um you know, in real life. So you've got um C five to T one here and then you've got your terminal branches here. There's lots of nerves that come off it that aren't labeled here as well, which you know, do become important. Um But what's interesting is you've got the overlay of different brachial plexus blocks. So, incline, supraclavicular, infraclavicular and axiliary are all different racial plexus blocks. Um And so where you put your local anesthetic will depend on, you know, which section you're blocking and it will have different effects and you can see they've kind of loosely labeled in blue where you would affect. Um, it's never as simple as that and it's not always as simple as blue or gray. It'll be s you know, intense anesthesia versus mild anesthesia, you know, on, on the different parts depending on which one of these blocks you choose. Um So we'll talk about the brachial pauser interscale block and this is done right behind the neck. Um And we're targeting the nerve roots as they pass between anterior and middle scaling. So this is anterior scaling here. This is a middle scaling here and you're attacking, you're attacking C five C six, which is bifid here and C seven. Um And it's, you can see from this little chart, it's really good for shoulder surgery. It covers the cap of the shoulder, but more importantly, the bony structures, if you're doing a shoulder replacement, for example, um it's really good for bone pain. Um C 345 keeps the diaphragm alive and this block will pretty much every time knock out your phrenic nerve on that side. So don't do them on both sides and just be aware who you're doing this on. So, if you're doing this on a real respiratory cripple, um, be aware that knocking out the diaphragm may be enough to tip and move the edge into needing ventilatory support for a short period of time. It's obviously also close to the er carotid and jugular. You can't see the car here, the jugular is there and the vertebral artery as well is kind of in your line of approach. If you really don't know what you're doing, you could very easily stab the vertebral artery which nobody enjoys. Um, axiliary is kind of a cousin of, of the in scale, but it's much less risky. So it's obviously got different uses as well. You're below the shoulder, so you, as you might expect, you're not gonna get any shoulder anesthesia. So it's no good for shoulder. Um But it does target the big three, you know, distal arm nerves. So, medial ulnar and radius as well as needing to target the musculocutaneous nerve as well. Um So you do it, you know, in, in the axilla, you're aiming for the axillary artery. Um and the axillary artery is just an extension of the subclavian as well. So you're aiming for the axillary artery. Now, that might sound dangerous, which in some ways it is, you know, you don't wanna stab the axillary artery, but it's useful in that if you can't see these nerves on ultrasound, which you often can't, it doesn't always look like this, then you can put local anesthetic around the artery, which you'll pretty much always be able to see. And you can be pretty confident that the local anesthetic is gonna track all around those that artery and anesthetize those nerves. And that means that it's a fairly reliable block as well to be able to get those three nerves if you just get local anesthetic next to the artery, um It's notably not next to the lung or the spine. So that's useful. Um And then last one, we sort of talked a little bit about for Ectoine. So the ecto spy muscles are a group of muscles, either side of the spine. Uh There are these ones here and they attach to the transverse process. Um and they sort of stabilize the vertebra, the thoracic vertebral particularly. Um but underneath that is what's called the right spy plane and that plane is in communication with what's called the paravertebral space. And the paravertebral space is where your dorsal roots live and therefore your cutaneous supply to the chest. So if you put local anesthetic under this space, it tracks round and goes to the paravaginal space and causes anesthesia for the chest wall, which is useful for breast surgery, for thoracic surgery. Um And as we said before, for rib fractures as well, um it, it is very useful because as you can see, this is not what you would do for a, this is a paravertebral block with this needle here. So you can see very clearly. You'd be pointing this towards the spine or if you're coming the other way, you'd be pointing it towards the um, lung. So, with a paravertebral, um, there's some pretty significant risks associated with it, whereas a um, a rectal spine here because you're just aiming for this bone, the transverse process, you're coming straight up here and landing on that bone and putting it under the muscle layer, you have a nice bony backstop, which means that you're not gonna accidentally skew the lung or the spinal cord. Um And you can also put a catheter into that space as well for, for analgesia, for example, for rib fractures. So you might see this one being done in A&E and you might be, you might see it being done in more and more in the as well. So just to wrap up, how can you take it forward as a, as a, a medical student going on some placements or even as a, you know, an F one starting on a, a surgical placement or something like that. Um So anatomy, you know, I really did not like anatomy in med school and um I didn't learn it unless I actually had to, but it, it is really important and I suppose, you know, if you've ever had that fear of being asked by a surgeon about anatomy and you've done a bit of reading, but just at the same time, think about the neuroanatomy and think about how you might um anesthetize that neuroanatomy. If you're gonna do anesthetics, you may as well learn the brachial plexus cos they will just keep asking you about it. Um Get familiar with ultrasound if you have a block that's happening, even if you're not gonna touch a needle, have a go at scanning, just ask if you know, try and replicate an image that the, that your anesthetist is has done or asked to be guided or just have a go just see if you can identify some structures because er the more you look at scans and the more you make those movements with your hand and see what happens on the screen and learn that sort of association, the more easy it become to look at what other people are doing, the more easy it become to do the whole thing. Um Obviously have a look at some blocks before you're attending. If you think they're gonna be happening and just ask, you know, ask, ask your nieces um about what's going on and usually you'll be rewarded. Um So, and then these are just some, I think really useful resources. Um So nice. A is the New York Society of Region Anesthesia. So very, very good. Um you know, regional community, a lot, some of it is be behind a paywall. Um But there's a lot of free resources and there's a lot of really good videos, really in depth, um sort of tutorials and really in depth like research based stuff as well. Um, reason I see in the UK is where the, the um plan A blocks they have, they go into much more detail about the seven plan A blocks. BJ. Education is a really good British journal education, um, sort of supplement that, that has tons and tons of good stuff and then there's lots, there's tons of stuff on youtube. You know, as I'm sure you guys are aware being medical students in 2024 2025. But um regional anesthesiology is unfortunately American uh is a really, really good sort of six or seven minute videos about individual blocks really well explained. Great, great graphics just really makes it work. And so those are some good places to start. Um So any questions II appreciate there may have been some questions as we go along that going in the chat. If there's not, that's fine. But does anyone have any questions? Oh God. Uh excellent Stone silence. Oh, let me have a sec. I see you in the picture. Um So this isn't something I've necessarily thought about and, and to be honest, I've not really seen, um I've not really seen it, it being used at all, I suppose. A I anything that is digital output is always gonna be not low hanging fruit but you know, a good place to start for A I and so there is tons of evidence about radiology and A I using radiology and tons of evidence, you know, for example, um retinal imaging and things like that. Um The pattern recognition is obviously the main stay of A I. So, you know, that would be potentially a place to start with. There'll be augmentation to um what you're seeing on a, on a screen for pattern recognition. I mean, already in, I suppose in point of care, ultrasound, you know, a lot of the machines now will have um pattern recognition of, for example, in, in, in echos, you'll have uh it'll be able to detect which bit of the LV you should be putting your Doppler and which bit is the LV OT and therefore it'll auto generate um either a, an ejection fraction or a um a cardiac output monitor. And so I suppose there is little bits creeping in but then the, the obviously the real um C proxy there and hopefully, what makes this indispensable is that you have to then put a needle there. Um And so that that side of it, I suppose is, is gonna be pretty difficult to um to really sort of replace. Um I suppose the other, the other aspect of A I is big data. And so whether there's gonna be more use for picking out who's gonna be suitable for regional anesthesia, which regional anesthesia techniques work best. But I, you know, I suppose you can apply that to anything really uh any, any big data cohorts? Is there anything you're particularly thinking about in terms of A I or anything that you've seen? I don't know if everyone's typing. Ok. Um So if there's no other questions, then I will and let you guys be on with your, um, prescribing revision. Thank you so much for doing that. Um I think I can't, oh, wait, someone has just all the recording they available. I, I'm not sure myself. I think that will kind of deals with all.