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Hi, everyone. Can you hear me? Yeah, we can hear you. Brilliant. My name is Amar Actor and I'm currently in Fy one in Birmingham Cui. And today I'm here to talk to you about peroperative medicine and anesthesia as part of mind, the Bleeps final year lecture series. Um So again, this is meant to be an introduction or a broad coverall for everything you really need to know um for perioperative medicine and anesthesia at the level at the level of vitals. So the way that we're going to cover this topic is firstly looking at a co a couple of key anesthetic concepts at the level of finals through the perioperative journey. This will include the preoperative phase, intraoperative and postoperative. And we'll also touch upon some important pharmacology, including pain management, which is a key area of focus of the UK MLA um curriculum. Then what we'll do is we'll tie up any loose ends and focus on other areas of the UK MLA content map that haven't really been covered through this journey. So just to start with, we're gonna start with um the per operative journey itself. So as I mentioned before, this is split up into three broad concepts, the preoperative phase before patients go to surgery and all the preparations that um that are involved in this, the actual in intraoperative phase where patients are actually undergoing the procedure and then the postoperative recovery um of whatever they've had in terms of preoperative um phase. We'll talk about the key things that the anesthetist needs to think about when they're doing their preoperative assessment. Certain preoperative risks that are common to almost all surgeries and the kinds of comorbidities that pose pose the most challenges to the anesthetist. We'll also then talk about some other important preparation points um Before patients go to surgery, then on the intraoperative um section of the presentation, we'll talk about the wh checklist and we'll kind of talk through a lot of key anesthetic um concepts through an ABC kind of approach. After that, we'll move on to the postoperative phase in which we'll talk about some key considerations that happen after surgery and some common complications. So, let's start with preoperative C. So firstly, when, um when, when you uh when a patient is about to be scheduled for surgery, um most surgeries uh involve a preoperative assessment with either an anesthetist or a nurse practitioner. In this assessment, we often consider the kind of urgency of surgery. Is this an emergency procedure that needs to happen almost imminently, an urgent one that needs to happen relatively soon or a scheduled or elective one that can happen. That is not as time sensitive. Once we've talked about the urgency of surgery, we need to think about the severity of the kind of surgery that the patient is going to have. Is this a small minor procedure on a per uh peripheral part of the patient's body such as a nail excision or a carpal tunnel release? Or is this something much more invasive that's gonna take a much more physi physiological um load onto the patient such as an invasive chest surgery or um major organ surgery such as a heart um or liver or even kidney transplant. Those are more surgical factors. And then we also need to think about patient factors. So one really important key question that anesthetist ask are, can this patient climb one flight of stairs just to get a gauge of the patient's exercise tolerance surgery is like running a marathon on the body. It's an immense physiological stress. And for us as physicians to know whether a patient can tolerate it, um we need to have some sort of a baseline of what this patient can actually do. So again, asking this key question of, can this patient climb one flight of stairs is a really good um lip stair. Then we also look at any key comorbidities that the patient has uh because this will really affect um how safe it is for them to undergo surgery and how effectively be they can undergo a general anesthetic. So one key tool that anesthetist use is the A SA classification system. This is a way of stratifying a patient's comorbidities. Um just to see how much of a surgical risk that they are, so most of us will probably be a SA one or a SA two. Notice that A SA one involves nonsmokers or non drinkin. So that would take out a lot of people who are generally quite healthy without any medical conditions, but pop them into an A SA two A SA three for, are your more higher risk patients? Those are patients that have significant comorbidities that are causing a, a large impact on their life. So again, the difference between three and four is that four has a constant threat to life. Um whereas three is just a significant comorbidity that's not um an imminent threat um to the patient's um survival and five is are often ones that you see in emergency situations, for example, uh an aortic um aneurysm rupture. Um So for a patient who is not expected to survive without that surgery, and A SA six is reserved for dead uh for brain dead patients who are donating or so, if we just take a look at some of the kind of comorbid disease that patients can have. Firstly, cardiac is one of the most important systems to consider heart failure is really important to consider because it uh limits the ability of the heart to respond under stress and during anesthesia. And it's one of the most um important comorbidities to consider um before surgery, ischemic heart disease is also important to consider because having prior ischemic heart disease increases the likelihood that a patient will have an ischemic event during surgery hypertension is, is another key comorbidity. Um Given the fact that if a patient has uh uh uh um a BP of over 100 and 80/100 and 10 surgery is usually delayed if possible. And this m um hypertension is aimed to be treated for about a month before reassessing the need for surgery. Again, in terms of dysrhythmias, um, any dysrhythmia discovered preoperatively should be fully investigated. Uh and surgery delayed. The exception to this is generally um af that's well controlled um at a heart rate of probably below 100 BPM. Most other dysrhythmias should be discussed with the anesthetist fluid stasis is also very important to consider. And patients with hypovolemia do need immediate fluid resuscitation. Again, we'll talk about the different types of ways that we can get fluids both as a maintenance um replacement and uh for resuscitation. And again, there is a high risk of patients becoming hypovolemic during surgery because of the fluid uh shifts and the blood loss is there, valvular diseases can also be a problem. Um, and any murmurs detected on a physical examination may need to be investigated with an echocardiogram. Again, aortic stenosis in particular is one to watch out for. So in terms of these comorbidities, the ways that we can investigate them are generally through an ECG, an echo or even a CPAP. The indications for an ECG are generally for patients who are over 55 because of the risk of silent mi I um in the in this patient group and anyone with a cardiovascular history or any symptoms. Contrary to what a lot of people believe an ECG is not required for every patient undergoing every surgery echo can also be used if you're worried about things such as valvular diseases or heart failure, anything to do with the actual um pumping of the heart and fluid fluid actually going through it instead of the electrical conduction, which is again best tested through an E CG CPAP is a more specialized um investigation. And again, what you really need to know about this is that it's just used for patients who we really, really want to stratify their cardiac risk just to get a much more fine um finer view of their um cardio vascular fitness. And the way that we test this is by doing uh putting them on a bike and basically seeing how well uh what level of exercise that they can reach. And we kind of uh the value that we use for this is a V two max. So we've talked about cardiac comorbidities, but respiratory are equally important. Anesthesia itself can cause a reduced respiratory rate, a fall in the capacity within the lungs. So, residual functional residual capacity, and it also reduces the ability of the mucociliary escalator to clear all that gunk that comes up through the chest. Um So all of these um can lead to risk factors, uh postoperative risk factors such as postoperative pneumonia and atelectasis. And these kind of emphasize the importance of deep breathing exercise, which we'll talk about in a second. So again, any patient who has a sh uh has shortness of breath or any respiratory background um will be uh will be indicated to have a chest X ray um before surgery. So again, any respiratory comorbidities and any respiratory symptoms, some other metrics, again, that can kind of be helpful for a respiratory point of view or again, the activity level, how far can they walk without getting breathless? Or again, as we mentioned before, can they climb a flight of stairs without getting breathless? So these um are on the left hand side are some key comorbidities that you or even risk factors that you should be aware of um that can make um anesthetic and surgery much more difficult from a respiratory point of view. So again, we've talked about the indications for um chest X ray, um asthmatics uh in particular should have uh peak expiratory flow rates. Um done. And bronchodilators should be continued post uh pre and postoperatively. And again, some patients may even require lung function testing depending on the extent of their respiratory comorbidities or if they're having a uh a particularly um systemically taxing surgery. So let's start with this first SBA. Now I'll give you guys a couple of minutes just to have a think um and just fill in the pole. Ok? A couple more seconds. Ok. So the correct answer is actually to delay the surgery for a month and treat the hypertension. The reason for this is because a BP of 100 and 80/100 is normally the cutoff for when we try to me, uh, medically manage our patients for a month before reassessing if they need the surgery. Again, the procedure in question is an elective one. So there's no imminent rush to get this patient to surgery. This was a completely different situation such as a, um, aortic um, aneurysm rupture. Then again, you wouldn't wait to manage the BP, you would go straight in with surgery. So there are some other key comorbidities that you should be aware of, um, in terms of different systems. So in terms of the gi system, one key one that you should be, um, aware of is hiatus, hernias. This is because hiatus, hernias involve a portion of the stomach being trapped above the diaphragm. Uh, and therefore, uh, any food that's caught in this portion, uh above the diaphragm can lead to food, um, being, um, aspirated up into the esophagus when patients undergo general anesthetic. Again, general anesthetics reduce um our airway uh reflexes and our ability to keep food down. Uh that's in the stomach, which is another reason why we fast our patients in terms of renal or hepatic impairment. It's important to get these and LFT S for any patients who are expected to have large fluid shifts in their perioperative periods or anyone with kidney or liver dysfunction. Again, these are very basic tests that you probably would do uh before most surgeries. But again, especially in these patients. Um one key thing to consider in terms of patients with hepatic dysfunction um is uh their coagulation, uh their ability to um generate coagulation factors. So again, you'd be wanting to look at the inr and making sure that that's well controlled. Um again, for these patients, you especially do want to get advice from the anesthetist. Um And again, uh dehydration is something you should try and avoid. Um with these patients for patients with a neurological history of tia or stroke. Um these patients are at an increase of further cerebro uh cerebrovascular events um perioperatively. Uh and again, a lot of them have residual neurological defects in swallowing uh and managing their airways. So by that, I mean, maintaining the patency of the airway uh and preventing food from aspirating. Um So, again, these reduced uh reflexes mean that they're less able to protect their, protect their airway and that they're more likely to suffer aspiration this is one of the reasons why a lot of stroke patients, um, need salt assessments, uh, to determine whether they are still, they still have a safe swallow or not. And that's likely a side from anesthesia. But it's a good concept to think about, um, as well in terms of the endocrine system, um, patients with diabetes have a core principle, uh, a key consideration that you should remember, um, which is that they should be scheduled at the start of an operative list to reduce the fasting period that they um need to undergo, try to schedule two hourly glucose analysis. Uh and diabe diabetics who are poorly controlled with their sugars. All those who are on regular insulin may often require a variable rate. Um IV insulin infusion, this is a contrast to the fixed rate. Um IV insulin infusion that patients have when they're in DK. So that's a nice consideration. One way to remember is that it's the opposite of DK. Uh And again, patients with adrenal insufficiency will need to have um steroid cover perioperatively. Um because in surgery, there is a natural response of the body. Uh a natural sympathetic response in patients who have um adrenal insufficiency aren't able to mount this response um themselves. So therefore, we need to supplement their um steroids to do this, the hemato hematological system. And coagulation is also important to consider perioperatively cause again, patients can have heavy blood loss um in this period it's important to do bloods before. So F ECs uh cross match. Um So crossmatch means to have blood available, whereas group and save means we just have an idea of their blood type, but there isn't blood um imminently available. Another key point is that sickle cell patients, uh sorry, sickle cell testing is required for all patients of a Carribean, East Indian or South American descent as well. So now on to the next SBA, I'll give you guys a couple of minutes just to work this one out. Ok? Just a couple more seconds. Ok. So the answer here is lateral um cervical spine, X ray. And a lot of you might be thinking, what on earth is this? So let's go through each answer one by one and then we'll talk about the correct answer. So, firstly, chest x-ray, there's no specific mention here um of any chest disease or any chest signs. So, again, those are the two kind of things that will indicate to get a chest X ray. Secondly, echo wise, there's no indication of any valvular disease or any heart um failure. Again, think about the blood flowing through the heart and those kind of conditions that will affect that more than the electrical conduction. Um then an ECG again, not needed because this patient is under 55 and there's no cardiac symptoms or any um underlying comorbidities and exercise testing. Whilst you'd ask whether she's able to walk a flight of stairs. This is not really a routine test and it's not specifically done due to rheumatoid arthritis. So, the reason that a lateral c spine x ray is required is because the patient has rheumatoid arthritis. Um for these kind of patients, they have a risk of something called atlantoaxial subluxation, which essentially means that a joint in the skull, the atlantoaxial joint um can kind of slip uh while it's more prone to slipping. And this is quite dangerous because it can put pressure onto the spinal cord at a very high level. So again, when patients undergo a general anesthetic, um where you need to intubate and to do this, we kind of have to crank the head very far back. Uh And this is what causes that risk factor. So again, anyone with rheumatoid arthritis, rheum to get a lateral c spine x-ray, another key assessment that you need to do um is ABT assessment. So this is a rough performer from a random a random hospital in the UK. Just to give you a kind of idea of the kind of factors that you need to be thinking about. A lot of hospital systems actually have this built in into the electronic um health records. But as of uh at the final level, you just need to kind of think about the risk factors for thrombosis and bleeding risk and kind of know that ABT assess vte assessment, excuse me, is a balance between the two. So for example, uh features such as active cancer age over 60 dehydration, no thrombophilias and all of the ones listed on the slide are ones that you, uh, kind of need to have an awareness about some surgeries specifically that you want to be uh some surgical and patient factors that you want to be keeping in mind as well are prolonged surgery, abdominal or pelvic surgery, prolonged bed rest, um, orthopedic knee or hip surgery, if the patient is obese and oncological surgery. So, we've talked about a lot of comorbidities. We talked about a lot of medical issues, but let's talk about some logistical things now as well. So firstly, one thing that comes up a lot in exams is fasting guidelines and this is also something you should generally be aware of um as a new f one. So the two numbers that you really need to remember are six hours and two hours after six hours, patients can only have clear fluids. So they can't have um any food. Um, after the six hours between six hours and two hours, um is when they're allowed clear fluids and then two hours before a procedure, um is when they need to be nil by mouth. Um, all adult patients should be starved for the six hours. And again, we've talked about the specific two hour um restriction of being nil by mouth entirely. There is some exception to this for small Children undergoing certain elective surgeries. We may be allowed milky drinks or breastmilk up to four hours preoperatively, um or even water two hours preoperatively. Again, sticking to that um preoperative um two hour rule. But again, the milk is what becomes a little bit contentious here. But again, this is more a practical point and not one that you'll be tested on, on exams. Antibiotic, prophylaxis is also important. And that's something you often discuss with the surgical team. Uh, and patients with heart valve pathology may need an uh extra antibiotic, prophylaxis against bacterial endocarditis. But again, this is something that's often surgically led, um, with, uh, liaison from the, uh, from the anesthetists with the surgeon. One common antibiotic that's um, prescribed is Cefazolin. Um, but again, what you should do is refer to your, um, local microbiology guidelines. It's also important to pause certain medications before surgery. And there are a couple of different principles that you need to know, um, in order to know what to pause and what. So let's try the following SBA and then we'll kind of go through those principles together the, a couple more seconds. Ok. Well, um, so those of you, uh, you who got fits, but again, I don't expect everyone to know all the ins and outs of this just yet and we'll go over that now together. Sorry, this is the kind of cheat sheet that you need to know for finals. There's not actually that many key considerations that you need to know. Um but these are the main ones, there will be some other things that might crop up on very niche questions. But as long as you know, these ones, um you should be covered for most questions. So, um if you want to take a screenshot of this slide, that might be a good idea. So firstly, cardiovascular drugs, these ones, you can continue all of them. Apart from two, again, these are very one similar class, these are of a similar class ace inhibitors and obs and these you stop on the day of surgery itself. Lithium is a drug that stopped about 24 hours before. But again, only for major surgery for anti tnfs, this is something that you will want to seek specialist advice for. So for someone who's got um you know, for example, IBD or an autoimmune condition or even on cancer therapy, and we have combined contraceptives and hormone replacement therapies. So anything that really contains estrogen and this is something that you stopped four weeks before, excuse me to um reduce the risk of blood clots. Um then we have uh steroids. So a patient who's um receiving long term steroids again, needs steroid cover as we mentioned before. So then we've got the anticoagulation. So, Warfarin DUA um and low molecular weight hamer, these are some general principles for them. However, in practice, this can actually differ a little bit depending on the patient and the surgery. So I would know these, um, for finals. But again, when you come to actually practice, I know that things might be a little bit different. So that finishes the preoperative um, care section of the presentation and now we'll move on to intraoperative care. Um What happens when a patient actually is in theater? So let's start with the, with this SBA I'll give you guys a couple of minutes just to think about this a couple more seconds. Ok. Well, on, for those who got it, so let's go through the answers one by one. So firstly, gaining consent whilst it's obviously very important to get consent before surgery. Um, it's not needed before emergency treatment. Um It's in the best interest of patients, checking the name, date of birth and if the patient knows if they're having the correct procedure again, for certain emergency situations, this isn't always possible. Um in terms of gaining IV access whilst it's required for most procedures. Um, it's not an absolute necessity. Um uh it totally depends on the procedure and actually for a lot of procedures in Children, we don't, well, for certain procedures in Children that are very minor, we actually don't need to get the access and intubating the patients. So for a lot of patients who have low risk short procedures, it's not needed to place an et tube. Um something I'll explain a little bit later. But the one thing that's done before every surgical procedure and every theater that you'll be in will be the wh, um, checklist. This is something you'll observe or you should observe across the world. Um, even if you guys are off on your electives, you'll still see something very similar being conducted. So one thing, uh, so here is the wh o checklist, just have to be familiar with this. You don't need to know every single point. Um, but if you are in theater, just try and think about this and try and see how you see this um conducted, it is very much um you know, uh in terms of the before induction of anesthesia bits. Uh and before the patient leaves the operating room, a lot of these things you'll have to notice rather than see explicitly. But before the skin incision is where there's often a time out and all of these steps are um verbally um talked through. So one point I wanted to touch upon is rapid sequence induction. This is something that you might have heard of. But what you need to know is that the there's, this is a unique type of intubation um or induction of anesthesia. That means that a patient can be quickly and safely induced into anesthesia um in an emergency setting where the patient hasn't fasted. The primary goal of this is to minimize the risk of aspiration. Um whilst also um getting them into anesthesia, it's a carefully coordinated procedure to minimize the time between starting the actual anesthetic agent and putting the tube down the patient's um throat um to reduce the risk of um the complication that is um aspiration. You don't need to know how it works. You don't need to know the ins and outs, just know that it's a thing basically. So now we're gonna kind of take the ABC approach of um important anesthetic concepts and that are relevant through the uh interop period. So some of the maneuvers and devices that you might see any c use um are listed here on the slide and these are also relevant for emergency medicine as well. So I'm sure you'll be familiar with the head tilt, chin lift, um and the jaw thrust, these are all maneuvers to kind of open up the airway. So one time the anesthetist might use, this is for preoxygenation, they're trying to fill the patient's lungs before starting the anesthetic agent to kind of give them the most amount of time between um shutting the patient down a bit with anesthesia. So getting the breathing tube in there um to breathe for the patient, there's a number of devices that you can use in the airway um to kind of facilitate this process to kind of um hold kind of stent and hold the airway open or completely create a new airway itself. So the first of these devices is an opiate and oropharyngeal airway. It's also known as a Cadel and essentially it prevents the tongue and soft tissues of the pharynx from kind of collapsing into the tongue, kind of flapping back on the soft pilot kind of coming down. Um It kind of prevents this um from happening and keeps the airway open. However, it's poorly tolerated in patients who are semiconscious because it stimulates the gagging reflex as it touches the back of the throat. Um as you can see in the image, but again, this is often your first line tool um for a patient if you can't get proper ventilation, um uh but you don't want to start invasive mea measures just yet. The next one is a nasopharyngeal airway. And this is um very useful to bypass obstructions in the mouth. One of the nostrils, nasopharynx or the base of the tongue. This is something you can put in a con uh in a conscious patient and it shouldn't stimulate um the pharynx as much as an O PA does. One really important. Um thing to note though is that there are some significant, some important contraindications to putting in an MPA. And this is a basal skull fracture. This is shown by a number of different signs um such as raccoon eyes as you can see by a basal signs. So that's bruising around the back of the uh the ear, the mastoid process and any leak of CSF from the nose or from the um from the ears. What a basal basal skull fracture. Is, is um the bottom of the skull and where you have the kind of three levels, um uh the kind of cavity that the that the brain sits in the bottom of that is fractured, putting in an MPA can directly shift the bones uh and worsen that fracture. So this is why it's an absolute contraindication. The LMA is another kind of device that's used and this is something that you push into the mouth similarly to an opiate, an oropharyngeal airway or a Cadel. Um And it sits above the vocal cords. Um You not to use it if there's an obstruction at or below the level of the larynx. And it's often used instead of intubating patients for short or low risk surgeries. One thing to know is that it doesn't provide a definitive airway, which means it doesn't protect against aspiration. There's only one device that does that out of the LMA, the O PA and the NPA and that is an ET tube. So again, this protects against the aspiration of gastric contents. Um using this uh this balloon um at the end which essentially creates a seal inside the airway, stopping any aspirated contents from entering into the trachea. Um Because of this tight seal, it also allows for precise control of ventilation that minimizes any leak. So the exact concentration and titration of gasses, you pump out through your anesthetic machine and into the tube is what often goes down into the lungs because of this, you can generate a higher concentration of oxygen as well. Uh which is what makes it a kind of high level airway. Um as compared to LMA S or um the Cadel or the MPA. There are other definitive airway devices that you, that it might be useful to be familiar with. But again, it's not essential at a finals level. This is a tracheostomy or a cricothyroidotomy, which are both um accesses to the airway um through the neck. And again, they have a very similar design to the ET tube, except for the fact that they don't go through the mouth, they go through an artificial opening in the neck. So we've talked about some of the airway devices that we can have. But there are also a number of different devices that you can use to administer oxygen without putting an airway in. So there's a, the slide is quite busy, but let's just run through each device one at a time. So in the top, right, you can see nasal specks or nasal cannula. And these are kind of the first option that you would try and use if your patient is a bit hypoxic, both inside theater or outside. And this can uh deliver oxygen from up to one to actually 4 L a minute. Sorry, that was an error on the slide. Um Then we have the variable flow uh masks, um the hug and mask um on the left of the nasal cannula image. And this can um deliver up to 15 L uh a minute um or 50 to 60% of oxygen. The non reb breathe mask on the right um can deliver an even higher concentration and again, up to 15 L a minute. Uh And the and the non rebreath mask essentially means that the patient isn't rebreathing CO2 um that they breathe out, which is what enables a higher concentration of oxygen to be delivered. A CPAP hood or a tight fitting mask is another type of way of delivering um oxygen. And then we have the venturing masks which are down at the bottom with the colors of vowels. These valves can be switched in and out to kind of titrate the exact percentage of oxygen that you want to deliver. Uh And these can come in 24% 28% 35% 40 60% as well depending on which color you choose. You don't need to memorize, which um which color corresponds to which percentage just know that the venturing mask is a thing um that can be used to titrate oxygen very tightly. And again, the main situation you wanna do this in is for patients with CO PD who you want to target sets of 88 to 92. Um And you don't want to over oxygenate them. There are some advanced ventilation strategies such as oscillators and ECMO S but then you don't really need to be aware of them at the level of finals. Um It's more for if you're interested and you might come across some awards or in ICU. So in surgery, we should aim for specific O2 SATS range unless it's an emergency surgery, um, or an emergency situation in which you should deliver high flow oxygen. There are specific patients who should have supplemental oxygen during surgery and may require oxygen therapy for several days. Um despite what their initial respiratory signs or SAS might be. These are patients with prolonged abdominal or thoracic surgery for these patients. Patients with preexisting respiratory conditions, those receiving IV opioids including PCA patient controlled analgesia. Generally, you do want to go um with what the clinical signs say, but these are kind of patients who you want to be a bit more aware of. Ok. Are they going to require oxygen? It can be useful to have an idea about mentals. Um and uh look at different uh methods of control for them. So we have volume, sorry, we have pressure control first which delivers a specific um inspiratory pressure at a specific respiratory rate. Um some problems that can arise with this is um something called volume trauma. Um then we have volume control, which is where a specific volume and respiratory rate um is delivered. But again, problems can arise um if the lungs are not compliant enough or if they don't stretch enough essentially, um that can lead to barrow trauma. So you can kind of see pressure control leads to problems with uh volume, volume control can lead to problems with pressure. Um So it's kind of fine balancing act when you're choosing pressure support is unique. Um because it kind of increases the patient's own in inspiratory um effort um to the desired level that you want. So it kind of just supplements the patient's breathing. And it's really useful for patients who are being weaned off ventilation or for patients who have their own respiratory drive that you just want to give a little boost to. Um That's uh often one that you might see a bit more peak is a really important concept when it comes to ventilators and breathing. What peak stands for is positive and expiratory pressure. Essentially, this kind of ventilation keeps the alveoli partly inflated um on expiration. So they don't fully collapse. The reason for this is um that when you want to inflate the alveoli, um there's a lot of resistance that comes if the alveoli is complete, be deflated. Um think of it like a balloon when you try to inflate a balloon. The hardest part um is when the balloon is floppy at the start. If there's a little bit of air in the balloon, it's a lot easier to inflate more air. Um because of uh the rules of compliance essentially without going into too much of the physiology. Um But again, patients with um A R DS often have um high peeps just to um enable easier ventilation. And this is kind of called bung sparing ventilation where we deliver low volumes, but we use high peep. Um That's something that can come up in final. So just be aware of that. So let's look at the ne the next ba now. Ok, a couple more seconds. Ok. So the correct answer is to intubate. The reason for this is the G CS. So one key um rule that you guys should remember is if the G CS is less than eight intubate. Um If you look at the G CS for this patient, if you combine the motor, the eye response and the verbal response scores, it comes to around seven. And if there's a mixed motor response, remember to take the best one. Um intubation is your answer. Um I know a lot of you might be thinking, measure the O2 sats. But again, um what is very quick to get a pulse ox on and probably in practice, you would do this in terms of an exam answer, it's gonna be intubated. So we've talked about um airway and we've talked about breathing. Now, let's talk about circulation and the cardiovascular system and how you can support this. So firstly, there's a couple of maneuvers that we can use if a patient is um in shock. So if they're hypotensive and not able to properly um deliver um the adequate circulation to their organs or their peripheries. Um, there's, and the maneuvers include, um, lifting up the legs or dropping the head of the bed down by putting the bed at, at the decline. Um, these kind of things can return venous, can increase venous, return back to the heart and the brain where they often needed. Most, you can also give fluids, which we'll talk about in a second. Uh, and there's certain medications that you can do uh that you can give. Um So for example, chronic drugs that affect the heart. So drugs that increase heart rate. So chronotropic and then drugs that increase contractility. So inotropic drugs, um and again, there are also other drugs that can act on the autonomic nervous system that you can give at the level of finals. You don't really need to know um the details of these. But if you're trying to aim for, you know, maybe higher marks, um then these uh questions about these drugs can come up, but again, I wouldn't prioritize them in your vision. So we mentioned fluids, there are a number of different types of fluids we can give uh and these can target different areas um or different kind of fluid compartments. So if we have a think about the fluid compartments in the body, um the body is uh made of made up of a significant proportion of water, but a significant proportion of this is intracellularly, then we have the extracellular fluid compartment and the intravascular fluid compartment. In terms of um maintaining hemodynamic stability, we're normally concerned about what's in the intravascular space. So that will be the yellow um section on the uh on the diagram. As you can see, it's actually a very small percentage of the total body um water content. So let's talk about some of the uh common fluids that we do prescribe. So firstly, dextrose, dextrose is a solution of pure water uh and glucose and once dextrose is, is administered to the body, the glucose in the solution gets metabolized very quickly, leaving pure water. Now, pure water distributes equally across all of these compartments, which means the vast majority of it will end up in the intracellular space. Therefore, if you're trying to get um fluid back into the circulation, dextrose isn't that good at doing this? But it's very good at treating dehydration, which is often um driven by a lack of water in the intracellular and extracellular uh extracellular spaces in terms of other crystalloid um solutions. So we've got dextrose uh and we've got um sodium chloride or we've got um Hartman's solution. All of these contain uh so sodium chloride and uh and um Hartmann's both contain high levels of sodium. The sodium does not cross the cell membrane. Um So that means that none of these fluids go into the intracellular space. Um which then means it's all in the extracellular uh extracellular space. So this will be either in the red or the yellow. So a good third of it remains in the intravascular compartment. So these are generally quite good at treating, treating hypovolemia. These are often your first line um measures for shock. After you've done some maneuvers, colloids are a unique kind of fluid that contain high amounts of large proteins that, that generate an oncotic pressure. That mean that they will remain in the plasma fluid and in the intravascular space. However, because they often have more side effects, um and they're generally more expensive, we uh we reserve these fluids for once we've given crystalloids. Um and when we're waiting for blood products, um and again, blood products um are often indicated for when a patient has lost a significant volume. Um and we need to replace um specific factors, um coagulation factors or platelets or red blood cells. Um or you know, if we just, if the patient is severely depleted, then we need to replace blood for blood essentially. So this is also a common um theme in uh trauma as well as surgery. So, if we haven't think about the types of fluid regimens, now this algorithm is one produced by nice for IV fluid therapy in adults. And it's one that's really useful to be familiar with. It kind of breaks up the three kind of ways that we can replace fluids. So the first is um fluid resuscitation and when we're assessing a patient with fluid replacement. We need to think is this patient hemodynamically unstable. So they have a low BP, high heart rate, shut down peripheries. Is this more of an emergency situation? In which case, they need fluid resuscitation, if not, they're generally quite stable. Um Or then we need to think about, are we gonna give maintenance fluids or replacement fluids? And again, the two main questions you need to, the two main things you need to consider when making this decision is, do they need uh fluid or electrolyte replacement? And is there abnormal distribution issues? So again, have a look at the IV fluid therapy algorithm for uh for adults. Um by nice, there will be this exact diagram and just go through it in a bit more detail. So now on to the next SBA, OK, just a couple more seconds now. OK. So this is the answer and we'll kind of go through um this in a second now. So here are the key takeaways that you need for fluid um prescribing. We talked about the three general areas. So, resuscitation, maintenance and replacement at the final level, the main two that you need to know are resuscitation and maintenance. So for resuscitation, um again, do your ABCD assessment and if a patient needs fluids, you'll kind of be able to tell based on things like tachycardia hypertension and peripheral shutdown, which you can kind of tell from raised cap refill. Uh Sorry. Yeah, prolonged cap, refill, weak uh and thready pulses. Um So what you do in this situation, which again, something you probably already know from clinical practice, we give 500 mils of saline um at a stat um as a stat dose or over 15 minutes. And uh what you want to do is reassess and give another bolus if needed once you've given 2 L, so up to four boluses, um you should have um expert help at hand. So in practice, once you've given about two boluses and you haven't seen any response, I would be contacting a senior at that point. Um Then we have maintenance fluids. So what we want to do um is give is talk about this in terms of the amount of fluid amount of glucose and the amount of um electrolytes we want to give. So you want to kind of come up with a fluid combination. Um That kind of fulfills the following criteria. So 25 to 30 mils per kilo per day. So for a patient who's 50 kg, about 1.5 L2 L for about 70 kg and 2.5 L for 100 kg. So for the pre previous question, in terms of electrolytes, um the second answer actually met everything apart from the fact that the volume was a bit too high. Um the third answer, however, um had, sorry, the the third answer um was the one that had too much volume. Um but everything else was correct. The second answer, however, met all the electrolytes and had the correct volume as well. So that's why it up to the answer. Um in terms of the um glucose, try and aim for about 50 to 100 g of glucose despite what the weight of the patient is. So if you give 1 L of 5% dextrose, that's fine for the lower limit. So try and include that as part of the fluid regimen, then we want to try and aim for one millim m per kilo per day of sodium potassium and chloride. The one that you want to use to guide this is going to be the potassium. Um As this is the one that needs to be within the tightest range within the body. If your patient has working kidneys, it's fine for the sodium and chloride to be a little bit over. Um So again, remember these key takeaways for resuscitation and maintenance. Um But again, if you want to know this topic more comprehensively refer back to the nicer. So now on to postoperative care, um what happens to patients after they've gone through surgery? So there are a number of key considerations that we need to think about per um physiological system. So in terms of BP, we need to think about um if there's uh postoperative hypertension or hypotension, which are both common, there are specific causes for each of these, which we'll discuss in a second. Again, myocardial ischemia, something which is more common for patients who have had previous um uh ischemic events in the past. Again, um hypoxemia is also a very common complication. Um And that's one that you need to treat quite imminently because of the importance of uh of B ABCD E in terms of the GI system, postoperative nausea and vomiting um is a very common complication of a general anesthetic and that's something we're gonna dive into a bit deeper. Um So oliguria is also common, um uh especially if patients have been um underhydrated and they might have suffered a prerenal AK I in terms of the neurological system pain is very common and this is something that we'll dive into a bit deeper and also confusion after anesthetic is also very common. And just generally, there are some other key things that you should consider after surgery such as hypothermia fever, which we'll dive into a bit more um and sepsis uh as well as pressure area necrosis. Given the fact that patients are often in awkward, uncom uncomfortable situations for extended periods of time. Pressure area necrosis is, is often something that you find more on the wards. However, for patients uh who are immobile and unable to move for much longer periods of time than just uh a surgery normally takes. So, taking a deeper dive into hypertension and hypotension, um sorry, these labels are the wrong way around. Um But you'll have to bear with me uh whilst I explain them. So, um on the left should be hypotension. So, anesthesia itself um can cause uh a kind of cause the opposite of um sympathetic response. I don't wanna say parasympathetic quite specifically. But what it does is it causes hypotension, reduced responsiveness, um reduced respiratory drive. So part of that again is the hypertension. Um uh and also patients undergoing surgery, lose a lot of blood volume. So, again, hypovolemia and because of the invasiveness of surgical procedures, sepsis, uh and other infections are also common causes of hypotension and hypertension can be caused by pain, anxiety, shivering, um from patients being cold. Uh and also CO2 retention as well. Patients who have preexisting hypertension who have had their medications um paused um or stopped even though we said that they're not meant to be paused or stopped before um can uh experience rebound hypertension as well. So, postoperative nausea and vomiting is also a very common problem. Again, due to pain anxiety, use of opioids as well. And due to certain anesthetic agents as well, often we can give a single dose of dexamethasone intraoperatively because of its properties to be an antiemetic um as well as the fact that it can help um generate a systemic uh sympathetic drive um that you need when you're experiencing systemic stress such as surgery. Here are some of the key risk factors that you should be aware of for patients who are young and female non-smokers. So, what this is kind of saying is that smoking is, um, protective against postoperative nausea and vomiting. Uh, and patients who have a history of motion sickness as well as patients who have surgery. Greater than one. How long your first line, um, antiemetic is often gonna be cyclizine, which is an antihistamine. Um, if that doesn't work, you can try Dansetron. Um, if cyclizine hasn't worked in 30 minutes and if this still hasn't worked, um, then you can try, um, prochlorperazine. Um, if there's no response after 30 minutes of Odansetron, metoclopramide is another antiemetic, but we try to avoid it, um, because it's a prokinetic. Um, and that's quite a significant side effect for patients who've had surgery, especially bowel surgery. So, pain is also another one. that is really important to know about the finals level. And one thing to remember with postoperative pain is that it is meant to start bad and get better as a patient recovers. So, what we want to do is we want to start with high levels of analgesia that are gradually tapered down. So we'll talk about the wh O pain ladder for those of you that are already aware of it. Um But what we'll start with is often a strong opioid and say if it's appropriate and if there's no contraindications such as gi um or renal pathology, uh, and then, uh, paracetamol, this will then be titrated down to a weaker op opioid and the opioid will be removed together. It's important not to prescribe two opioids together because the combination of their side effects can be very dangerous. And this also includes um not prescribing an opioid or as a regular drug or as APR N. Um if the patient has a PCA, it's also important to remember that paracetamol doses should never be given closer together than four hours. And for certain patients, for example, if they are under 50 kg or if they have uh liver impairment, you need to reduce the, you need to half the dose of paracetamol. So, postoperative fever is another important complication to be aware of. And this is something that does get tested on exams. So here's a kind of useful way of remembering it, wind water, walk, wound and wandering about drugs. This kind of splits the most common causes of postoperative fever based upon the time that they present. So patients who get fever in the first day or two, it's most likely gonna be something like atelectasis. Um or a pneumonia atelectasis is essentially um collapse of the alveoli um that aren't able to reinflate and this often happens after surgery. Um or for example, a patient who's been um sedentary for an extremely long time. For example, on a ward mobile, um water is the next cause of postoperative fever, which essentially means a UTI or an IV line infection. And walking is a DVT or a pe and wound is more obviously a wound infection. And then after seven days is when you start worrying about any drugs or any antibiotics that are are paradoxically causing the fever itself. So surgical site infections is something that you should be aware of as well. This is something that's highlighted on the UK Malay um content that so again, there are certain risk factors in terms of patients, for example, patients who have diabetes, patients who have other infections around the body. Um and there are certain surgical factors. So for example, patients who have um more invasive surgeries, uh and more larger scars or scars that are left to open. Um orthopedic surgery is also more higher prone to infection. Uh and the complications of uh infection and orthopedic surgery is much more severe, which is why um you'll find orthopods are very, very particular about infection risk. Um What certain ways that you can identify surgical wounds, spreading, erythema, localized pain pus or discharge from the wound or a persistent pyrexia that is non resolving. Despite treatment um for these wounds, it's possible for uh for, for, well, for wounds that are infected, it's possible for them to split um which is called dehiscent. Um and the wound can also break down as well. Um In terms of key investigations, it's very important to look for an in uh infective source and visualize. So this would uh take the form of wound swabs and cultures, blood cultures and then relevant surgical site imaging. For example, if you had surgery on the foot and you're worried about a surgical site infection, this would be um ap and lateral x rays. Uh and potentially an MRI in terms of management, it's important to remove any sutures or clips in the infected area because there can be a nidus of infection, uh kind of source of infection and to do targeted antibiotic therapy. So, first you'll give broad spectrum antibiotics. Uh And then once you've got cultures and sensitivities back target um your therapy to the bugs that are actually present in the site. Again, any site that's infected should be regularly monitored. Um and any pus uh should be suitably drained as well. Uh Sometimes it's useful to go back um and debride um any infected tissue. But again, this is something that's normally left up to the surgical team. So here are some images of surgical site infections. Um And some of these are also wound dehiscence as well that you can see. So, sepsis, this is a common um postoperative complication or at least one that you should definitely be thinking of for any patient who's had surgery or anything invasive. So, some of the signs that you should be thinking of or signs of shock uh or signs of general infection. So, tachycardia, hypotension, fever, shaking and chills, normal or clamminess, confusion or just disorientation, shortness of breath, uh any rash or pain or discomfort if a patient just seems generally quite off. Um this could also be a sign of sepsis, which is very nonspecific. And one more practical tip I would advise is take the word of senior nurses if they suspect sepsis treat that. Um that worry very seriously because often they can have a good gut feeling of this kind of condition when we treat sepsis. We think of it in terms of the sepsis six, which is three things in and three things out, an easy way to remember. This is kind of grouping each three thing in and 333 things out. So the three things we wanna give her fluids, oxygen and antibiotics, the three things we want to take, um which means we basically measure is urine output, lactate and cultures. So urine output relates to the fluids. Um you're giving so you want to get a fluid balance, lactate is a measure of hypoxia um in the tissues. Um So again, this relates to oxygen and then cultures relates to the bugs that are present, which are targeting with the antibiotics. That's the way that I found um easier to remember the sepsis six if that's something you trouble with. So now on to the next SBA, right? OK, a couple more seconds. OK. So all those, those of you guys who picked it up this question is asking your malignant hyperthermia for those of you that haven't heard of this, this is an autosomal dominant condition in which patients experience muscle rigidity and hyperpyrexia. In response to certain anesthetic agents. Typically, the inhaled agents um or uh antipsychotics as well. Um So it's also known as neuroleptic malignant syndrome as well, um can be raised. Um And this is something that we treat with Dantrolene. In actual practice, you'd often give a benzo first. Um but the definitive treatment is known as Dantrolene, but it's often expensive and more difficult to acquire. Um which is why um diazePAM is norm or other benzodiazepines are normally first line. So malignant hyperthermia is one of the um uh complications or adverse effects of anesthetic agents that you should be aware of um at the finals level. The other main one I would say is suxamethonium ap uh apnea or succinylcholine um apnea. Um Those two conditions are the ones that I would um be aware of even though they're not as explicitly mentioned in the UK MLA content, they're something that have come up in the finals. Um quite a lot historically. So we're just gonna take a quick break. Um Just to give you guys an opportunity just to give some feedback and please let us know um what you think about these presentations, if there's anything you think could be improved. Um Again, this is really helpful for us to kind of make these sessions better in the future once I've given you guys a minute or two just to fill this out and we'll continue on with the rest of the presentation. Yeah. OK. So, um, if you can, uh this will be on the end of the presentation as well. Um So I'm just gonna whiz through the final bit because I know we're overrunning a bit. Um So the next bit now is just going over some core presentations of conditions we haven't quite touched upon yet based upon the UK MLA content. Um So, firstly, pharmacology, so just to have an idea of the kind of drugs that we give in anesthesia, um there is the um anesthetic triad essentially, um which involves paralytic agents, analgesic agents, and hypnotic agents. And all these is all about numbing pain, paralysis is all about reducing movement and hypnotics are all about inducing that state of anesthesia where patients are unconscious. The other two classes of drugs that we can get alongside these that are not part of the triad or autonomic drugs that um help manage our cardiovascular status in our patients and antiemetics, which we've already touched upon. So, these are some of the anesthetic agents that you can give are generally split, split into two categories, inhalational and IV the drugs that you should know about um for inhalational agents or volatile gasses and, and nitrous oxide. Um I'm just not going to go through these in too much detail. Um What I would recommend is just knowing the main side effects of them, the IV um you know, the propofol is the one that's used the most. Um and thiopentone is really used for um, r sequence in induction or, uh and etomidate is used uh in patients with um card uh with cardiac impairments um because it provides cardiovascular stability because it doesn't produce that hypo um hypotension. Um And we have the paralytics again, just know that succinum or succinylcholine is the main depolarizing one, which means it causes a contraction before it causes the relaxation. Whereas the nondepolarizing ones are the ones um that just cause relaxation straight away. Suxamethonium is the one that's no reversible. Um However, uh which is what uh what makes it more difficult to manage. Um But there are uh easy reversal agents for nondepolarizing blockers. Um Classically, we've given neostigmine and Glyco uh Pyrro glycopyrronium. Um But there's newer drugs such as Suam that can directly reverse um nondepolarizing blocks. Then we have the analgesic ladder which we've touched upon um more uh earlier in the presentation. So, again, postoperative pain is meant to start bad and get worse, which is the opposite um of cancer pain, which is what the um wh o pain ladder was developed for. So, again, start with your stronger opioids and then, uh as well as nsaids and paracetamol and then gradually titrate it down. Um As you move further away from surgery and as pain improves neuropathic pain is another important one to consider. And this um instead, so there's two types of pain. Um The first type, which generally generally responds to and paracetamol opioids. The other which is neuropathic pain, neuropathic pain is caused by damage to the nerves rather than damage to the tissues. Um So these are uh examples of that. So, damage of the nerve itself or pressure um or mass effect onto the nerve. And again, these are your four neuropathic agents that you should be aware of at the final level. You should also be aware of regional and local anesthetics. Um So you have spinal epidural and peripheral nerve blocks. Uh and spinal and epidurals are often used in childbirth. Um A peripheral nerve block can use in orthopedic surgery or surgery on the extremities. Um or for example, in certain situations where we don't want to give a general anesthetic or we want to give some sort of um anesthesia to mean that the patient can be awake but not feel pain. Metastatic bone pain is another key consideration. Um when you're thinking about anesthesia at the finals level, and the main thing you need to know is that there's three kind of lines of treatment. First, strong opioids don't be afraid to give cancer patients very, very strong opioids, um especially for metastatic bone pain. Whenever you give opioids, remember to prescribe naloxone on the P RN to balance the risk of overdose and also remember to give a laxative as well on the regular prescription. Um Bisphosphonates are your second line if that doesn't work. And radiotherapy can also be considered another um, drug that you can consider using is denosumab, which reduces um, bone activity and can reduce the bone pain from metastatic bone, uh or uh bone mets. The other drugs that you can use, um, are ones that we touched upon briefly earlier. So the emergency drugs are the ones that are act on the autonomic nervous system. So this includes vasopressin such as metaraminol, noradrenaline and ef uh ephedrine and adrenaline. Uh adrenaline can also be used for suspected anaphylaxis antibiotics we've touched upon. Again, this will be more surgically led. And then you've also got the antiemetics, which we talked about for postoperative nausea and vomiting. You can also give patients sedatives if they are agitated before surgery such as benzodiazepines. This is very commonly done. Um even especially in Children as well who can be very uh anxious before surgery. So we've touched upon now more all of the key anesthetic concepts. Uh Now it's just time to tie this all together with a couple of core presentations and conditions based on the UK family content map. So the first one is Perret arrhythmias. This is basically if a patient has a heart rate that is too high. Uh sorry, this is basically a patient that can have um tachycardias or bradycardias. These are two really useful algorithms to know. So what I would recommend to you guys is go on the Recess Council and just study these algorithms in more depth. Um Again, the main thing that you want to identify first is if there's adverse features or not. Uh And this will kind of split off the algorithms into the respective pathways. The next is cardiac arrest. Uh Again, the main thing with this is to consider is this a shockable or nonshockable rhythm. Um And again, these kind of rhythm, these rhythms are shown on the slide. But again, try and go through these algorithms in a bit more detail to get a really good understanding because these come up not just in SBA S but also in ACY as well. Breathlessness is another um core presentation. Um And again, there's different causes of uh breathlessness. So you can have airway obstruction in which uh there's a blockage of the actual airway, even though the respiratory um the the lungs themselves that are creating the respiratory effort are working. And so these are some common signs that you can see on the left apnea is where there's no actual respiratory effort from the diaphragm and the lungs uh and the muscles of uh respiration. So the intercostals and respiratory distress is a combination of the two or another factor that means that there's insufficient um air coming into the chest cavity. In terms of how you manage this, the first thing you want to do is sit your patient up, give oxygen. And if that still doesn't work, consider some airway maneuvers that we talked about earlier. If these still aren't working, you, like you want to consider an airway. So one of the ones we talked about before. So an O PA depending on the level of consciousness MPA or if necessary, even an et two anaphylaxis is also a really important one of the common signs and often it can be mister Damn questions if there's, if the question doesn't mention swollen lips or swollen face or a rash and if someone's feeling nauseous or if you've got a high heart rate or if there's collapsed, think of anaphylaxis. And again, here is the key thing that you need to remember which is the dose and don't confuse us with the cardiac dose, which is one in 10,000 for uh some of the algorithms that we talked about earlier. Um Just over here. Oh, sorry here. So going back to um a few things that you need to think about, then we also have misplaced NG tube. So if a patient has a misplaced NG tube, the first thing you'll want to do is aspirate the ph if it's not under 5.5 that means that the tip of the energy is pro might not be in the stomach. So therefore, you need to do a chest x-ray to identify the location um of the mg more accurately. Um These are the, are the key criteria that you want to be thinking about to make sure that the MG is in the correct place. Um Before you um certify it to be safe for feeding in practice. Um uh in a lot of hospitals, you need to be a read or above to safely um uh certify an NG tube in the right place using a chest X ray. But again, this is something that does come up in exams and that you should know at your level. So, thank you very much. Everyone that concludes this presentation, we've basically talked about um the surgical journey, some of the drugs and tools that s have uh and the core conditions and presentations relevant to you based on the UK um map. Um If you guys could leave any feedback um based on today's presentation, we'd really appreciate it. And I hope uh and I hope the content of today's presentation was useful for you guys. Um So thank you very much. Um If you've got any questions, please just drop them in the chat otherwise you can email them to our team and we can try and get back to you. And yes, um certificate of attendance um is contingent on providing feedback. Sorry, that's a bit sneaky of us. But yeah, thank you so much for that really comprehensive talk on, on anesthetics and per perioperative medicine. Uh Emar what I'll do is is if you're OK, we'll just end the call with the, with the red bottle down below. Is that right? Sounds Good, perfect. Thanks so much. Goodnight room. Good night everyone. Thanks for joining.