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Perfect. I think we've got quite a few people already joining. So we'll just wait for the numbers. Welcome everyone. I think we've got quite a few people who already join. So I'll just make, just give it a couple of minutes. Ok. I think we'll wait till four past seven and then we'll do introductions. Ok? I feel like the numbers are probably starting to um round up a bit, so maybe we'll do introductions. So welcome everyone. Thank you for joining us today. Um I just want to introduce my name is Stephanie and I'm the president of Manchester Anesthetic Society and just want to give a quick introduction to NATS. It's a brand new initiative in collaboration with over 10 universities across the UK designed to enhance anesthetics, education and address gaps, not always covered in medical school. So it would be great if you could drop us a follow on our meal page and keep up to keep updated with all of our future weekly events, including our event next week, which is a talk by University of Edinburgh and also don't forget to complete the feedback form at the end to receive your certificate. Now I'd like to hand over to GEO to introduce himself and the speaker for our session today. Oh, yeah. Hi, everyone. I'm GEO. I'm the president of Newcastle's Anesthetics and Critical Care Society. Um Thanks Steph for having us here today and sorting this all out this. I'm really looking forward to it. Um I'm really excited to introduce you all to Doctor Keith 40. He's a consultant anesthetist up here in the North east who's really kindly offered his time to talk about monitoring anesthesia today. Um So I haven't talked for too long, but, well, if I do, I'll let him go on with it. Thank you. Thank you geo. Can everyone hear me? I'll assume that's a yes. Ok. So, first of all, thank you for inviting me. It's a, it's a real honor. Um I don't often get asked to talk like this and uh it's nice to speak to so many of you. Er, it's particularly nice. Thank you for the introduction, Stephanie and GEO. Um because about 30 years ago I was a graduate of Manchester Medical School and a very proud one at that. So it's nice to be speaking to some guys from Manchester and the topic of the talk today is monitoring in anesthesia. Uh There's a couple of things that I'll mention. Um one is that uh I noticed your introduction on the, er, medal website listed me as a leading expert in the field of monitoring and anesthesia and I think if I'm honest, I wouldn't call myself that I'm just a jobbing consultant and aist who uses this equipment on a daily basis as part of his everyday work, just setting expectations. So tonight we're gonna talk about uh what is monitoring. So what do we mean by it? Uh We're gonna do a little bit of the brief history of monitoring. We're gonna talk about what we actually use to monitor patients when they're in the operating theater. Uh We'll talk a little bit about guidelines and standards because I think they are important. Uh I'm gonna spend quite a bit of the time in the second part of the talk talking about the lessons that I've learned the things that I've picked up through approximately 30 years of using monitors and looking after patients in the operating theater. And then for a bit of fun, we're gonna do some future gazing. So we're gonna have a look at what's on the horizon and then what we might be monitoring patients with when you guys are consultants. Um And along the way, we'll pick up some wider lessons in medicine just generally, I think, ok, feel free by the way, um during the talk to either pipe up uh and, and interrupt or to put questions into the chat. And uh we'll pick those up, I'll pause at various points throughout the talk and we'll have a look at the chat and see if we can answer any of your questions? So what is monitoring? Uh The Oxford English Dictionary describes it as a verb to observe, supervise or keep under review, to keep under observation, to measure or test at intervals. And that's pretty much what we're doing in the operating theater. We're using a variety of instruments, including our hands, eyes and ears, uh to measure, observe and record all sorts of parameters um throughout the perioperative period. So that's before the operation during the operation and after the operation crucially. So the picture on the right is an anesthetic chart from a case I did last week. And um, you'll see there's a whole load of data on there. There's a lot of information. Um We've got things like um the patient's height and weight and BP and usual BP. There's a whole load of blood tests. There's my interpretation of the 12 lead E CG. There's just a whole load of stuff on there that's not monitoring. We're not planning on repeating that regularly. Um You might occasionally do some bloods during a case, but, but I wasn't planning on it for this case. Um So they're really worn off readings and that's not what I would call monitoring. This is the first page of about three pages of this operation. It went from 930 in the morning all the way through to tea time and you'll see on that, this is where we're recording most of what we would consider monitoring. So you can see if I can just highlight it. We're recording pulse oximetry, we're recording n tidal carbon dioxide, we're recording the inspired oxygen fraction and then the obvious things like BP and pulse and things like that temperature. And we're also recording the airway pressure and how that changes as we alter the position of the operating table into a fairly jaunty 28 degrees of head down tilt. So the these are the things that I would consider a monitoring. Um And you'll notice we're doing them on a fairly frequent basis. The pulse and BP are effectively doing every five minutes, although this guy had an arterial line in. So we're actually really recording it on a beat to beat basis. So that's monitoring. Um And that's fairly typical of, of most cases I would argue. Um And certainly, certainly the bigger cases we're doing those, we're doing those measurements frequently, often and all the way through. I'm hoping at least a few of you will be familiar with this painting. So this is Hinkley's depiction of what's commonly referred to now as Ether Day 16th of October 1846 at Massachusetts General. So, what we're seeing in the picture here is uh William Tg Morton, who's the guy who's just peeking out in the middle there with the mustache, uh administering Ether to William Abbott while he has a um tumor removed from his jaw and neck. Uh And this is widely regarded, although probably erroneously as the first public demonstration of ether for non dental surgery. Oh, and general anesthesia for non dental surgery. Um, there's a lot of controversy a, a about the painting Hinkley wasn't even born, I think at the time that this took place, uh, and, and about the accuracy of it and everything else. But I want to draw your attention to the guy who is on the right here. This is a doctor William Haywood. He's a prominent Boston physician at the time. Um almost certainly wasn't actually there at the time. Um I think he was added to the picture later. But crucially, I want to draw your attention to how he's depicted. He's holding the hand of Abbot during the operation. And crucially, he has his finger on the pulse of the patient and that my friends was state of the art perioperative monitoring in 1846. So, what I'd like to do now is just take you through while we're talking about history, take you through a brief timeline of how we got to where we are now. So 1846 Doctor Haywood with his finger on the pulse while uh Morton administers the ether. Not long after that, there was quite a lot of discourse in the scientific literature about um respiration being the better monitor of the patient state while while you've got them gassed under ether. Uh So various discourses on whether it's better to look at the rate or the pattern or the character or whatever, but lots lots of scientific papers being published on that. Um You'll notice that uh for the 1st 50 years or so of general anesthesia, we didn't really write much down, we just kind of passed the gas and patients seem to do. Ok. But then towards the end of the 19th century, Cushing as in Cushing's disease, um started as, as quite a junior doctor, uh encouraging people and promoting the use of anesthesia records. So the first anesthetic chart, like the one I showed you earlier, um comes about in the sort of the 18 nineties, we start to get the ability to measure BP reliably noninvasively uh around about that time as well 1896. Um although it's still pretty impractical for a lot of operations, cos you have to get right up close to the patient. But, but that was ok in those days. Uh 1903, we've got Eindhoven developing the EC G. Um Those of you remember that, I don't know if you remember the history of the ECG that, that was originally sort of done with organisms. Initially a goat. I think it was standing in a water bath. So that's not massively practical for the operating theater. But over the course of the next couple of decades, um EC GS came into common usage in surgery and they're probably the first um electronic or electrical monitor that's used in surgery round about 1920 Arthur Gell um published, it was actually a book, but it was a series of scientific papers about his observations of the stages of anesthesia. Um And that was the first time that anyone had really laid down. How you couldn't, you could estimate the depth of anesthesia with a patient by making simple observations of things like their respiratory pattern, their pupils, their pulse, their general demeanor and things like that. So the stages of anesthesia comes from that all the way back in the 19 twenties, 19 fifties, we uh start to develop something called oscillotonometry. Er This always makes me smile when I see this cos um this was AAA means of not quite alternating BP measurement, but at least making it a bit more practical that you didn't have to listen to corot cough sounds. So it's a a machine without all the electronics, but similar to the modern machines we use today for measuring BP that you have to uh you sort of pump up the the um the cuff, you know, one of those squeezy things and then you watch the needle and it as it bounces around the mean arterial pressure that gives you the mean arterial pressure and systolic pressure and then eventually you get the diastolic pressure. So if you imagine a visual representation of corot cough sounds, that's what the Oscillo tonometer gave you. Uh It still wasn't massively practical. It took quite a while to get a reading and it was a real skill. Uh, capnography starts to come in in the 19 sixties, er, after a sort of significant increase in interest in carbon dioxide during submarine warfare of the second World War. Um, so that comes in but doesn't massively take off as a popular anesthesia monitor. So it was feasible to do it but it never really sort of got traction for the next couple of decades. In stark contrast to the pulse oximeter, which doesn't come along. Obviously, we need uh cheap, reliable and easy to manufacture electronics for a pulse oximeter. So they don't really come along until the 19 eighties but very rapidly get adopted. Um So by the time I start anesthesia training in 1994 pulse oximetry is is universal. Whereas capnography is still a little hit and miss at that point, everyone's breathes a sigh of relief as propofol um comes into widespread use in the mid eighties. But the key thing I think for tonight's talk, the key thing that happens in the mid eighties is that the Harvard Medical School publishes its standards of monitoring, expected of anesthesia practitioners. And this is the first time that a large influential body um had published standards of monitoring. Up until that point, people used what they fancied by and large or maybe what their little hospital told them they could use. But this was the first sort of international publication of standards of what was required. The Association of Theists of Great Britain and Ireland, as they were known, then followed suit in 1988 and published their minimum standards of monitoring, which were very, very similar. Um And then actually innovation to a large degree slows down a bit from there. We we develop depth of anesthesia, monitors, auditory potentials and uh bi and things like that in the late 19 nineties and quantitative neuromuscular monitoring comes in roundabout then as well. Um But mostly it's about training standards and iterative improvements in equipment and practices from there on in there have been a few developments in the last couple of years in terms of monitoring, but I'm gonna include those in the sort of future gazing bit at the end. OK. I'm just gonna quickly check the chat. Thank you Jack for telling me you're good here. Um There's no more questions in the chat, so I'll move on. So this is now the fifth edition of the Association of anus er guidelines on standards of monitoring. It's a really important document and if you um are interested in anesthesia intensive care, it's worth a read as a student. If you're practicing anesthesia, then you definitely need to be familiar with this document cos this is this is the law as far as it goes in terms of monitoring straight off the top recommendation. Number one has always been there and in this edition, it's phrased as adequate supervision requires that an anesthetist should be present throughout the conduct of anesthesia. You've gotta be there. You can't leave the patient once you've anesthetized them, they're your responsibility and you must stay with them. That's pretty much non-negotiable. And that is the main standard previous editions. Um, I phrased it slightly differently. A little bit more flo flowery. It was the most important monitor is the continual presence of the anesthesist in the operating theater, which is a nice turn of phrase I thought. So you're gonna be there, you can have all the kit in the world. But if there's no one there to watch the screens and listen to the beats, then all of that kit is effectively useless. So your presence as the anesthetist is the number one recommendation. But beyond that, there are some recommendations for all anesthetics and um the minimum standard is as you can see their recommendation to E CG pulse oximetry, uh noninvasive BP and capnography and they should be started before you administer the anesthetic and continue right the way through to the post anesthesia care unit, which we still still call recovery. Um There are some other things which depending on the circumstances you might need. So gas uh analysis is one. So that's oxygen and volatile anesthetics. And uh there are also recommendations for other bits of kit depending on circumstances. For instance, if you're doing total intravenous anesthesia, this version of the guidelines will recommend you use a depth of anesthetic monitor. Ok. So that's the standards. What do we have use that? So I'll presented, presented this in tablet form, which I'll give you a couple of minutes to read. But then we're gonna go through each of them pretty much individually. Ok? Enough of that, we're gonna go through it. So you'll all be familiar with EC GS. Um The standard sort of configuration for interoperative use is a three lead ECG A as you can see demonstrated in the lower picture. So just three cables, right arm, right, left arm and some way down on the left, lower rib cage, E CG just tells you heart rate and heart rhythm in that configuration, you can't really get an awful more from it than that. Um It's a single lead. Um That's all you're gonna be able to see heart rate and heart rhythm. But also crucially that's the thing that gives you your beeps. And I would argue, I'm terrible when I get into theater, I'm always turning up the beeps on the machine so that I can hear what's going on because if you've got your back turned or you're distracted with something else, you can maintain your vigilance by listening to those beeps. If you put on a what's called a five lead configuration. So that's a slightly different set of cables uh in the positions as you've shown there. Um Then you can start to make some uh judgment on morphology of the ECG. So crucially in most modern monitors. Now, if you have a five lead configuration, you can look at ST segment morphology and sometimes the monitor will actually keep an eye on that for you. You can see in the top picture. Um It's giving us a reading of an ST segment elevation of naught 0.1 millimeters which is obviously not clinically significant, but, but if it were to go up, the, the machine would pick it up. Um, we don't actually, it is a rather bizarre picture. We never put the, the V lead there. The V lead would normally put in V five, sometimes V four, in this sort of position to principally keep an eye on the left ventricle. So we would do that for patients who have bad ischemic heart disease or having major surgery where we're worried about myocardial ischemia. Still keep an eye on the rhythm in the right. Um, but you can also make some judgment about, uh, myocardial ischemia. The other basic monitoring is just good old fashioned noninvasive BP measurement. Um, it's simple, it's cheap, it's easy. It's noninvasive, it doesn't hurt that much. Um, it's perfectly fine for most cases, to be honest. Um, it is however intermittent. Uh, and if you're sharp eyed, you might notice that in that bottom picture, I can bring up my pointer. I've got this set to 20 minutes. Now, that wouldn't be any good for the association standards of monitoring because it should be measured every five minutes. But in this particular case, we're going to be seeing this case a lot. Uh I was also monitoring the BP using an arterial line. So the noninvasive one, there was really just meant as a backup. If we're using muscle relaxants of any description, then we should be using neuromuscular monitoring. So you you may have seen this, if you, if you've been in theater for any length of time, you may have seen this. Um This is uh a quantitative neuromuscular monitor. So we've got two electrodes sitting on the, the, the lower forearm there, basically over the anatomical site of the ulnar nerve. And they're gonna apply four electrical stimuli quick succession and that's then going to stimulate the adducta pollicis muscle and the thumb's gonna move um inwards towards the, the little finger. Uh That's assuming that the neuromuscular junction is intact. If it's blocked, then it's not gonna move. So we use these monitors to um judge the onset and the offset of neuromuscular blockers, drugs like Rocuronium, vecuronium, atracurium, that kind of thing. Um So they're supposed to be applied before you give the drug so that you can check that they're all working. And then as you give the drug, eventually the stimulus, the electrical stimulus is gonna produce less and less of a response at the film until eventually nothing will move. And then, you know, the patient's paralyzed So the way we record that, the way we describe it is with a train of four, that's what tof stands for. Um And that's as I said, four stimuli, quick succession. And what we do is we look at the ratio of the strength of the fourth twitch compared to the first twitch and normal is 100% or even above. But as people are, are recovering from neuromuscular blockade, then they might start with just one twitch or just two twitches. And then there'll be maybe a third twitch develops a little bit later. And once you've got three twitches, you can start to see something called fade, which is where the first twitch might be quite strong. But then the second twitch is weaker and the third twitch is very weak and that's um characteristic of neuromuscular blockade with non depolarizing muscle relaxants. Uh You can see fade going across all four twitches sometimes and it's not until that fade has disappeared. And the four twitches are of roughly equal strength that we would be happy that the patient had recovered from their neuromuscular blockade. So 90 above is the standard. Um But even 90 isn't really normal. Um You'll see this number pop up again later, cos this was actually me having the thing put on me while I was awake. Um The reason we use these is to prevent inadequate reversal of neuromuscular blockade, which continues to be a problem. Um You'd think we'd have cracked it by now. We've got all sorts of drugs available. We've got all sorts of ways of monitoring it really well. Um, we still seem to have people ending up in recovery who haven't fully recovered from muscle relaxants anyway, something for you guys to improve on. So, if we are using total intravenous anesthesia, we would use some, we would recommend you use some form of depth of anesthesia monitoring. So this would often be um processed EEG or bis is a commonly used one narcotrend is another. Um This is basically a single channel ec ge eg sorry that you can see sitting on my forehead and er that's er put through a process, it's called process eg cos the, the signal from that is then put through a very complex mathematical algorithm which is proprietary, they will tell you how they do the formula. Um And then it comes up with a number and that number is a simple nondimensional number between zero and 100 um reflecting your conscious level, your level of brain activity. So zero would be practically well would be a flat line E eg with no electrical activity and 100 is a normal awake eeg. And in between there's various different levels of sedation, you might run someone at about 8085 something like that. And uh for surgical anesthesia, we're really looking for the bis to be somewhere between 4060 less than 40 is considered deep coma. Uh And we try to avoid that because that's probably not good for you to be that deeply unconscious. So that's processed eeg that's commonly used with total intravenous anesthesia. If we're using volatile anesthesia, then we would use monitoring of the n tidal anesthetic agent. So tidal just means the last bit that you breathe out the end of your tidal breath. So end tidal anesthetic agent um is used to, to measure that. Now, that's not a marker of consciousness, not a direct marker of consciousness. That's just literally what you're breathing out. It's a marker of what's what's in your lungs. Um But the nice thing about volatile anesthetics is that uh there isn't a huge therapeutic window. And by that, what I mean is that we use a concept called Mac. Uh some of you might be familiar with it and forgive me if, if you are, but I'll explain it. So Mac is the minimal LDL concentration required to prevent movement to a standard surgical stimulus. So what that means is if you've had no other drugs but a volatile anesthetic and we give you one Mac, which is different for different drugs, but whatever it is for that drug, we give you that, then 50% of the patients will move and 50% won't. Um Now you might argue that's not a particularly good statistic for anesthesia. You know, if half your patients move, you'd probably consider given a bit more. Um But, but that's, that's where we draw the line and then we, we sort of give an amount based either side of that. But the good news is that most patients plus or minus a little bit will be reliably unconscious at one Mac. Um So zebra fluorane is the volatile I'm using in the picture at the bottom. Most patients, the, the Mac for zebra fluorane is age dependent but, but in, in most adults, it's around about 2%. Um So between sort of 1.6 and 2.4% pretty much everyone's gonna be unconscious. Um So you don't, by measuring it, you can be reasonably confident that your patient is unconscious even though you're not looking at their brain at all. Uh You can just be confident that the drug will do what you know, it does to most people. Um This one was a little higher by where this is a pediatric case, uh that I took the screenshot from. And uh so the Nidal Selu in here is 3.1 which is higher than it needed to be. Um But from a pediatric case, you, you can see that actually it's not that much higher than it needed to be. Um because it was only 1.2 Mac. Ok. I noticed we've got a question in the chat. So I'm gonna take that now if that's all right, Roy has said, I understand that Sugammadex is used for muscle relaxant reversal of certain drugs N MBA S. But I've heard of a cheaper alternative that's used instead when Sugammadex isn't necessary. Would you know what that is? Um Well, thanks for the question, Roy, that's a good question. Um First thing I would say is that there are two cheaper alternatives. So one is that Sugammadex is now off patent. So it's an awful lot cheaper than it used to be. So we're using the cheap generic version of that. Um The only cheaper alternative that I'm aware of is just using neostigmine, which is what we've used for decades um until Sugammadex came around. So, Sugammadex is a specific um binder of the aminosteroid. Uh muscle relaxants, don't worry about the chemistry of it, but, but basically, rocuronium and vecuronium, it only binds those two things. So all the other muscle relaxants out there. So Gammex doesn't do anything to so to reverse those and reverse the poor term. But, but everyone uses it. Um We use a, a drug called Neostigmine, which basically just increases the amount of acetylcholine that's available at your neuromuscular junction and that's cheap, that's cheap as chips. However, it has been in short supply lately. So for all it's cheap, we haven't been able to get hold of it for a while. We can now. But it, but for months we were struggling to get hold of it. So I hope that answers your question, Roy, if it doesn't feel free to res the question later. Moving on just cos we've only got an hour capnography. Now, if somebody were to ask me, what is the hardest working monitor, I would have to say capnography. Um So capnography is just a measurement of the carbon dioxide that you breathe out. Um And the, the reason it's there in the guidelines and the reason it has to be present whenever we administer general anesthesia is that it tells you whether or not you've put the tracheal tube in the trachea, have you put the tube in the right place? The gold standard for figuring that out is tidal carbon dioxide. And so that's why it's there, but actually, it gives you loads more information. Um So n number one is, you know, if you're ventilating someone, uh ental Co2 will allow you to see if you're ventilating them adequately. If you're not ventilating them enough, then their ental Co2 will go up and if you're ventilating them too much, their entitled CO2 will go down. So it allows you to tweak your ventilation until you just in the right zone. If the uh carbon dioxide tray suddenly disappears, that might be a sign that somebody's disconnected your breathing system from your airway device. Um That happens particularly when surgeons are working around the head. It, it does happen. Um So that's one way that we pick that up. Uh Capnography can also tell you when the patient's got bronchospasm. So if you look at the top picture, that's a screenshot from one of our anesthetic machines. Um You see that you've got a nice sort of rectangular wave to their capnograph. It goes up, it, it has a fairly flat straight plateau and then it comes down that's normal. Um The bottom picture is a sort of graphical representation of what's commonly referred to as sharks fin. You can see why can't you? Um So that slow rising expiratory phase of ca of carbon dioxide with a normal sort of a pause and then inspiratory phase, um that's indicative of bronchospasm. So patients with asthma or COPD will often have that shape to their capnograph, that shark spin. So it tells you that it can also tell you if you've got cardiovascular collapse. Uh because uh if there's no blood going around the body, no blood leaving the heart, no blood going through the lungs, then there's no carbon dioxide delivered to the lungs. Um And so your capnograph trace just suddenly drops down to a small amount. Um I can also tell you about your paralysis as well. Um So if the patient starts to breathe, there'll be a little dip in each of these capnograph traces. And um that'll tell you that your patient's starting to breathe. And the other thing it can tell you uh is whether or not the carbon dioxide has been adequately removed from your breathing system. So, depending on what kind of breathing system you're on either you've got an adequate fresh gas flow coming in or that your soda line is working and absorbing that carbon dioxide. Um And if, if it's not, um and the patient is breathing in carbon dioxide, then you get a raise in this baseline a bit like this one. So that instead of coming all the way down to zero, it may come down to there and then go to the next breath. So that raised baseline tells you your rebreathing, really hardworking monitor. Where would we be without cap good old fashioned pulse oximetry is also part of the minimum standard. After capnography, this feels like a bit of a disappoint where you think oh a pulse oximeter must be amazing. It does all that work and tells us when patients are hypoxic and it does. Um but that's all it does. Uh apart from of course, it goes um fairly flat when you have cardiovascular collapse because it is a pulse oximeter. And if you don't have a pulse, then there's no oximetry. So cardiac arrest and cardiovascular collapse is one of the things that the pulse ox sign can warn us towards and hearing that nice pulsatile normal cap uh pulse oximeter is always reassuring. So I'm moving on, we use an awful lot of other monitors. So temperature is, is actually part of the minimum standards, but we only usually measure it every half an hour or so. Uh you need to keep an eye on your inhaled oxygen concentration and also any other gasses like uh Tyl anesthetics, sometimes we use arterial BP. Uh The case I've been using to illustrate had that we rarely use CVP as a monitor these days. I don't know if you've um you've seen in theater much p patients having central lines, but by and large, we're putting stuff into that but not necessarily measuring it. We do measure it because that's how you know that the line is properly placed, but we rarely act on the value of the central venous pressure. Um There's been a numerous studies looking at the the efficacy of using it as a piece of information versus other pieces of information. And CVP S has really fallen out of fashion as a, as a monitoring tool, but we still measure the pressure because that's how, you know, if your line is blocked or misplaced, we measure cardiac output in, in a variety of different ways in theater, whether that be through an arterial line or a Swan Ganz catheter or um some other form esophageal Doppler maybe. And in specific circumstances, you might measure all sorts of other things like neurosurgery. You might measure intracranial pressure or neuro ICU or you might measure transcranial Doppler and things like that. Um But they're sort of niche in terms of general anesthesia in a general hospital. Ok, quick pause for questions. Roy's back on. Uh Thanks for answering. That comes my question. Good. So, Sinead Mooney, is there a rule for measuring CBP in the ICU? Um Yes. Um, but actually I think it was the ICU literature, the ICM literature that largely drove our move away from it as a useful piece of information. So I know our intensivist don't put an awful lot of store by it. But again, because the lines in place, they have to measure the pressure to look for problems with the line like it being displaced or something. Um, but I don't think they make an awful lot of decisions based on it, but clearly, if your CVP is minus seven, you're probably underfilled. And if your CVP is 20 or 25 or 30 then something has gone seriously wrong with the right side of your heart. So it's not like it's useless information, but chasing the CBP as, as, as I did earlier on in my career is not something that we do now. It is what it is. Er, so bilal, er, curious to know what surgery was from the anesthetic record that starts from breakfast to tea time. That was, uh, a radical robotic, uh, cystectomy. So that, that's about standard around about seven hours in Sunderland. Anyway. Um, maybe in Manchester you do them a little quicker. But, yeah, around about seven hours for that is, is pretty normal and we do much longer operations as well, even in a general hospital like ours. Um, you know, we do 1213, 14 hour operations occasionally. Um That's a challenge, but that's for another talk. Moving on cos we're short on time. Keep the questions coming in though. It's really good. Uh I'll come to your question in a second. Jack cos um I want to spread the questions out a bit. Uh Right. So now we're on to the lessons learned bit. Now, this is really just me spouting off. Uh There's no great rhyme or reason to any of this. Um But I just thought it's part, it's things I've learned from staring at screens for a long time. So the first one monitors lie all the time. So if you're in theater, I want you to picture the scene, you're in theater as a student and some alarm goes off, there are lots of alarms but you know, alarms are going off crazy. Um And you look around and you expect, you know, the place to spring into action and nobody seems to be doing anything and one of the reasons for that er is it might be that they know that this happens quite frequently. Uh theater monitors, alarm all the time for various reasons. Some of them which do prompt immediate action and a lot that don't. So for instance, um let me think of an example, I suppose pro possibly one of the best examples is if you put your pulse oximeter on the same arm as your BP cuff, then every time the BP cuff inflates and goes beyond systolic pressure. There's no blood flow to the finger and the pulse oximeter stops reading and it will alarm and it will display some worryingly low number like 50 or 60. And this is one of those things where it's, it's kind of like a marker for when novice anesthetists um suddenly start to get the picture and have good situational awareness. Cos most of us know that that's what the problem is. But you can sometimes watch people frantically trying to figure out why their patient has suddenly become so hypoxic. Um And that's just one example of uh you get a lot of false alarms. Um Lots of things that seem dramatic but maybe aren't. So as another example, uh a couple of days ago in theater, everything was ticking along nicely. And then suddenly our capnograph of our patient who was breathing spontaneously completely disappeared like there was no carbon dioxide trace at all. And you think, you know, it could be disconnection. It could be that the patient has stopped breathing for some reason. It could be cardiovascular collapse and cardiac arrest. It could be all of those things. What it actually was was me standing on the sampling line. Um And, you know, I figured that out reasonably quickly, well, embarrassingly, not, not immediately. Um And it took a while for everyone to be reassured that actually it was ok, everything's fine. It's just me with my big plates of meat in the wrong place. Uh So that's an example of why monitors lie all the time. The next question is what does it even mean? So we're measuring all this stuff. Um And we start to measure new things and one of the things we noticed or I've noticed when you start to measure a new thing is you suddenly discover a whole new set of states of imperfection. And I'll give you an example. Prior to 1981 pulse oximetry wasn't used in operating theaters. Basically, if your patient was breathing and pink, you are happy, you know, pink is good, blue is bad. Um And as long as they're pink, then it's probably gonna be all right, we start measuring pulse oximetry routinely and regularly and you start to notice that, um, lots of people tick along with oxygen saturations which aren't particularly good but aren't bad enough to make them cyanosed. You get cyanosed at around about 7580. Um, so, you know, there are loads of people just toddling through surgery with SATS of 82 83 84 85%. Um And previously, we'd have been happy with them cos they're pink and, you know, we wouldn't have known any better, but now you've got this thing. What do, what do I do? Is it important? Does it matter? We were happy with them before? Should we start treating it? I mean, that's pretty easy. You just turn up the oxygen. Um But we've had this with lots of modalities of monitoring. So when we started introducing quantitative neuromuscular monitoring, we suddenly realized that people who we thought had recovered from their muscle relaxants actually haven't quite recovered from their muscle relaxants and we should be working harder to, to allow them to recover. Um So every time you introduce a new monitor, you're gonna get that situation where you get a whole new set of things that you've got to worry about. But you also to counter that you also get advance and sensitive warning of the problems and that's why we do it. The reason we're doing all this monitoring is to pick things up early or to pick things up that we wouldn't have noticed with our eyes and our ears and to do something to make some form of intervention which is then gonna hopefully improve surgical outcomes. Good. Next question, does it matter? Well, this is, comes back to the whole idea of surgical outcomes. Um So making your monitors nice and pretty with all the numbers where they're meant to be and no alarms going off is very satisfying. Um But really it shouldn't matter if it doesn't make a heap of a difference to outcomes for patients. So being comfortable be well, not suffering complications going home in a good state, that kind of thing. So does it really matter? And the answer for some things is obviously yes. So if um, you put the tube in the esophagus and don't notice that's gonna end badly for the patient. Uh, they'll probably die. Um, but if the capnograph tells you that you've done that, then, um, you can put it right. So that's a clear example of, yes, monitoring does matter. Um, there's some other things as well. Um, it would appear that being hypotensive when you're elderly and having surgery is probably not good for you. So keeping a close eye on the BP and reacting to it when it falls is probably going to improve patient outcomes. The there, there's a number of other things. Well, bis lower than 30 is associated with poor outcomes. So that's one of the reasons why we measure it even when you're having a volatile anesthetic. Um The next thing is, is kind of a consequence of the plethora of monitors that we have now. So we've got a lot of stuff, a lot of kit, a lot of wires, a lot of noises and beeps and it can be quite confusing environment to work in, in theater. There's a lot of stuff that you've got to pay attention to. Um And I've lumped this in with cognitive loading and task loading. So those of you who have done any psychology, apologies with my um cod psychology, but cognitive loading theory is a, is a thing amongst popular psychology. Um There's only so much you can handle at any one given time your working memory is such that, you know, you can only take so much information in. Um So we have to think about that. Uh I'll give you a good example of both cognitive loading and task loading. So there's a, a monitor called the esophageal Doppler. And uh it's a good bit of, it's not particularly new. It came up in the 19 nineties got very popular round about the turn of the century, the two thousands. Um because there was a whole raft of scientific papers published, which suggested that using it to deliver what we call goal directed therapy. So that's basically giving fluid and vasopressors in the right time at the right dose to achieve sort of optimum cardiac output and, and therefore, um good outcomes for, for surgery. And there was lots of papers published which seemed to suggest that that that worked, that, you know, patients did better if you did that. The trouble with oesophageal Doppler is that this is what it looks like. Uh it's that long sort of windy thing that looks a bit like an NG tube that goes down your hooter or uh in your mouth and it goes all the way down your esophagus. And it's meant to sit round about just below the arch of the aorta and look at the descending aorta. And it uses Doppler, you know, the Doppler effect, same thing as speed cameras users um to measure velocity down the aorta. And that then allows you to work out cardiac output. Uh Lovely bit of kid. Nice, simple uh sort of mathematics that anyone could work out. Brilliant. Loved it. The trouble is it's really fiddly. Um So it's focused. So you have to get it down to exactly the right depth without obviously being able to see the heart like in the diagram. And you've got to twist it, turn it um until it's looking at exactly the right bit of the body to see the descending aorta. If you get it 100 and 80 degrees in the wrong way, and it looks at the right ventricle, then you get a completely different but uh confusingly similar picture. Uh So it takes a lot of faff and I found despite wanting to use this because it seemed to be good for my patients if I did it took up a lot of my time. Uh And I was spending up sort of investing a lot of effort in it and probably to some extent neglecting other patient care things that needed doing at the time. Um So there is a downside to some of these monitors, particularly if they have a high task loading. So esophageal Doppler isn't particularly cognitively loading. The numbers all make sense and it's quite easy to follow, but it's a, there's a lot of task loading and it can take up a lot of your time and that might be worth it for the information or it might not. Um So that's cognitive and task loading. We're not alone in this. We're not alone in medicine. You know, surgeons. Um often complain about cognitive loading when they're being asked questions whilst trying to concentrate on operating. Um pilots, talk a lot about cognitive loading and task loading and they take specific steps to try to reduce it and minimize it. Um You know, we're not alone there. Um I'm sorry, just to let you know we've got about 10 minutes left to um Yeah, II have got about seven minutes of talking to do no problem. But thanks, you just answer questions as well. So, yeah, good. I'm gonna skip that. I had a whole spiel about uh how some, some monitors, new monitors, reduce task loading, cos the Von Recklinghausen's tonometer there that you can see on the left that looks like it's from the 19 fifties because it is um got replaced by the Diamma, which is automated and literally, you know, it took away maybe, yeah, minutes every hour um of of extra time that you could spend looking at your patient. Don't forget of course, that the monitors aren't the only thing we're looking at. We're also looking at the patient. We're keeping an eye on what these guys are doing um and talking to them all the time and we're watching what's going on on their screen as well just to make sure that it isn't all going red and we're keeping an eye on what we're giving and we're checking the urine output and everything else. So there's an awful lot of stuff going on that isn't just on the monitor screen. It's complicated, but that's partly what makes it interesting. So, if you're interested in a career in anesthesia, the ability to process that information and make sense out of it and to intervene where intervention is necessary. That's an important skill. Right? And my final lesson learned is you can write the rules but will people follow them? So we introduced the er minimum standards of monitoring document, which has been on the go since 1988. Um And that's recommended quantitative neuromuscular monitoring for well, eight years now, nine, nearly nine years uh 2015 was when it said you should be using quantitative. Um I still see my colleagues not using them despite the fact that we now have them, although we've only had them for the last two years in my hospital. Um And we still based on all the, the literature and a recent audit in my region, we still have the ad patient who's arriving in recovery, still partially paralyzed. It's not good enough, the guidelines should be stopping it, but it's not because people aren't following what they should be doing. Um So yeah, you can write all the rules you like, but somehow you've got to persuade people to actually follow them. Right? A couple of quick examples for fun So this is my actually, no, I'll go back to questions quickly and then um we play through these videos and then I'm pretty much done. So Jack asks, what's your favorite anesthetic drug regime? Do you prefer to use TIVA or volatile? Um If I'm honest, II quite like doing TIVA, I mean, I'm comfortable with either obviously and up until relatively recently, the majority of my cases were done on volatile just because of the, the kit we had available in my hospital, but we've just had a bit of a kit upgrade. We've got loads of TIVA pumps available and this is really available. Um So I'm doing a lot more TIVA than I used to. It's probably a nicer patient experience, generally speaking, but it's a bit off and sunny asks how good is bis at measuring awareness fairly good? I would say, um, there's a degree of random number generation to it and slavishly following the number, um can be troublesome. But if you can interpret the E eg a bit as well, then, um, it's reasonably good and it probably helps and it's part of the recommendations now. So we should be following it. Um So it's fairly good but it's not fail safe. You can have people remembering their operation despite having a bit of 55. Um Speaking of which have a look at this, the guys in theater in giggles um doing that because they thought it was hilarious that I would be measuring the cognitive function, but that's me awake with abyss of 98. Uh We'll move on. This is someone asleep. By the way, this, this one over here is someone asleep and you say they've got a very different e eg trace. It's got very slow delta waves and a little bit of relatively low amplitude alpha waves uh whereas this is very different. So that's asleep and that's mostly awake. So just for giggles, this was me testing my neuromuscular function. That's four strong twitches with a 98% off ratio. So that's me with a normal neuromuscular function. Uh I'm gonna skip that cos that's boring. That's just pulmonary function curves with pressure volume less interesting. So the future, the last couple of minutes thought we'd gaze into the future. This is technically not the future. This is a AAA sort of settled product that people are using, but this is something called the null monitor. Er and this is gonna be the next thing in widespread use. I think it's what it's a measure of. No su exception. So that's probably worthy of some explanation. Um No su exception is the physiological response to a noxious stimulus. Um So if you're awake and you are undergoing nociception, then what you feel is pain because your cerebral hemispheres are able to process that not su exception, figure out that actually that hurts um and and form an emotional and behavioral response to it when you're under general anesthesia, you can't form your cerebral hemispheres aren't working. You can't form emotional and behavioral responses to pain, but you do still have a physiological response. You'll have seen it when your surgeons make the incision, sometimes the heart rate and the BP go up. That's the kind of thing that, that we're talking about with no su exception. So this null monitor uses a variety of different techniques. It, it's, it's effectively similar, you know, like a polygraph that they use as a lie detector in the States. They're always talking about a polygraph. It's kind of like that they use ski skin galvanometry, plethysmography, heart rate and heart rate variability, a variety of different sort of physiological parameters. And again, distills that into one easy to read number. And that will uh basically tell you how much nociception the patient is experiencing. They're not experiencing it cos they're not gonna remember it but, but their body is reacting to it. And that allows you to get your analgesia just right, not too much, not too little given it at the right time to prevent surgical stress response and things like that. Um So that completes the, the company are very proud of this, that completes monitoring of the triad of anesthesia. You might have come across this if you've been in theater and anyone's talked to you through it. The triad of anesthesia is hypnosis, being unconscious, immobility, muscle relaxation and analgesia and up until now we've been able to give drugs to do this, but we haven't really been able to monitor it. So that's, that's the near future. That's the horizon. We haven't got this yet. Not many places around the country have, but it is commercially available. It's still fairly new technology though. So it's going to need a bit of evaluating and assessing. What about the rest of the future? Um, well, there's lots that we could talk about that. Um I think one thing would be, um, what about the human factor? Anyone fancy wearing a body worn camera while they're at work? Um, human factors are very important in medical error and medical problems. Um, so how are we gonna monitor those? Um, well, my car, if I nod off, notices that my eyes are closed and tells me a warning, wake up 40 it's time to stay the car. Um, imagine if your operating theater could do that. Imagine, you know, we measure the temperature in the operating theater like, you know, 17 degrees, 18 degrees, whatever. Imagine if we could measure the emotional temperature in the operating theater. Imagine if you had some way of picking up if people were shouting or not communicating or making errors of understanding these things are medium future. Um And I'm just putting them out there that there's nothing currently on the horizon, but just some thoughts cos human factors aren't really the big source of error these days. Um, what else could be in the future? I suppose it's 2025. Um, so we can't really finish the talk without talking about A I, er, and again, I don't think this would be all that difficult to implement. But imagine if, does anyone remember, are you old enough to remember the Microsoft paper clip thing? So, when you were trying to write a letter in word, it would pop up and say it looks like you're trying to write a letter. Can I help you with that? Well, imagine if your monitors through a bit of machine learning, um realize that when the BP goes down and the heart rate goes up sometimes that means the patient's bleeding. Um And imagine if after 10 or 15 minutes of that happening, the monitor beeps it and says, hey, Keith, the blood pressure's gone down, the heart rate's gone up. Do you think the patient might be bleeding or along the lines of um you know, the BP has dropped dramatically, the capnograph looks like it might be bronchospasm and the heart rate's now 100 and 30. Have you considered anaphylaxis? So those kinds of things I think could be built into monitors relatively easy. That kind of machine learning is the kind of thing I have in my phone. Um So, you know, I don't think it would be all that unrealistic to have that. Now, you could argue that that's the kind of thing your mate should do you know your, your trainees should point those things out to the monitor. Um Or, or your ODP, but in the absence of good mates and good O DPS, maybe a monitor could do them anyhow. Um A couple of quick questions because time has run out and the best monitor of all for improving surgical and anesthetic relations is to keep an eye on that one. So I'm not gonna overstay. My welcome. What's the most common perioperative complication, uh, pain and nausea in, in our hospital? Probably more pain than nausea. But in some hospitals, it would be nausea is relatively common. TIVA is less likely to do that to you. So that's one of the main drivers for trying to use more TIVA is that's less likely to make you feel sick. But don't be fooled into thinking particularly by surgeons that anesthesia is the only cause of nausea around surgery. We do bariatric surgery in my hospital, operating on the stomach makes you sick. Doesn't matter. A hpe of what kind of anesthetic you've had some surgery just makes you sick. Uh does lack of effective analgesia intraoperatively? Sorry. This is Iola um does lack of effective analgesia intraoperatively, increase the chance of chronic pain postoperatively. Yes. Um And that's one of the big selling points of that monitor. Um So yes, and particularly waking up in severe pain is bad one we talk about, you know, sometimes when patients wake up in severe pain, they get quite upset. There's always an emotional component to pain. So, you know, it, it's part of the process, but then they start catastrophizing, then it doesn't matter what you give them, they're always gonna be in severe pain, at least for the foreseeable future. So, having them wake up comfortable and getting it just right is, is an important thing. And Sinead says, is there any new literature you'd recommend about human factors, communication and anesthetics that you mentioned? Um Well, the association has a guideline on it. Um So as an easy read primer for Human Factors in anesthesia, I would suggest going to the guideline section of the Association of Anest website and that is worth a read. And then there's a, there's a whole lot of references in that which will then point you in the direction of the, of the sort of the original papers for that. There's a lot of it. We, we were quite early to embrace human factors um in the same way that we, we as a profession, the association and the college um were quite early to embrace climate change and, and responsible sort of use of resources and also fatigue. So, you know, we, we were one of the first people to really recognize fatigue as being a major issue in the medical workforce. Um So I hope that answers that. And on that note, I've slightly overstayed my welcome, but thank you very much for listening to me. It's been an absolute pleasure and I'll stick on for as long as anyone wants to ask any further questions back to you geo Yeah, thanks Keith for that talk was really interesting and I'm sure everyone enjoyed it as well and excited. Um Yeah, I think if you want to say again, big, thank you for having us um step for, for sorting out this call. Um It's been seems to have worked out really well on buying the scenes here. So that's great. Um And yeah, thanks again, Keith um for this talk really good. Um I think I'm not sure if there's any or I think at this point, maybe people just wanna pop up and mute themselves if they wanna ask a question. Um Please feel free to do so. Uh Yeah, I'm just looking at the chat lots of. Thank you. It, it, it's an absolute pleasure. I've, I've actually really enjoyed it. Um Although it was a bit nerve wracking, um when geo first asked me to speak, I kind of thought it would be me popping to the medical school in Newcastle and speaking to a couple of dozen people. Um It wasn't until later that he spoke on me that it was a national thing, but it's been an absolute pleasure talking to you. I've really enjoyed putting it together. Are most people from Manchester or is it, is it truly national or is it international? Um part of it is. Some people are tuning in from all over the world so it's kind of international. Yeah. Um That's very kind of you Bianca, that's guy on it. Wow. Truly international. I should have handed in my CV. But I did work II know it's not Guyana but I did work for a year in the Caribbean um just at the turn of the century. Um One of the most formative experiences of my entire career. Yeah, if there's no more questions or anything, I don't know if I was muted for that. Um Happy to, yeah, stop the broadcasting and then everyone can enjoy the rest of their evening if that's ok. Thank you so much. Absolutely. Thank you. It was a pleasure, absolute pleasure. It was a pleasure having you. Thank you very much. Um And yeah, have a lovely rest of your evening. Yes. Will do take care.