Computer generated transcript

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

Hello, I'm Harvey Pin. I'm a consultant in emergency medicine and prehospital emergency medicine. Uh And I'm going to talk to you today about exercise associated collapse. So what I'm going to talk to you about this? Well, Lucy has kindly asked me to give a lecture on heat injury, uh and heat illness. Um but I'm a firm believer in talking about the undifferentiated patient. And in order to diagnose heat illness or heat injury, one needs to have got through a series of processes. Um in order to make that distinction and heat illness and heat injury falls into the broad category of exercise associated collapse. So what gives me any um reason to give you this talk? Well, as I say, emergency medicine and prehospital emergency medicine, but I've also got an extensive background in wilderness and expedition medicine. And uh more importantly, probably I've deployed with the military too hot countries in the past on operations and had significant experience of um soldiers, sailors and airmen undergoing exercise associated collapse in association with heat. I'll try and keep this lecture reasonably short, regionally succinct uh and focused on the expedition environment. Uh e think about things that you can do before you travel. Uh Think about things that you can do during your travel and think about things that you can do when someone collapses in front of you. So what I want to do to start with is just show you a video just to give you a bit of context about what uh exertionally associated collapse looks like. Some of you may have seen this video before. It's quite famous, but it really does show some of the things that go wrong when you exercise to at the high end of your vo two max. So have a look at this uh video clip and then I'll discuss some of the things around collapse associated with exertion. Now, Johnny has to win and to be sure of taking the title and right now he seems to have lost control of his legs and this is worrying, oh, and he's starting to slow and there is a little way to go. There's half A K to go and Johnny is running out of time and he's losing. He's losing his sets of direction. This is worried. Oh, goodness me, this is a horrible sight. Jonathan Brownlee has lost it now and has staggered to a stop at the side of the course and Alice has stopped to help him a lot and Alistair is going to try and carry his brother home dramatic scenes in Cozumel as the Olympic champion carries his younger brother towards the podium. Oh my God. I cannot believe what we are seeing here. Mac. Is this allowed? Is he allowed to help his brother? Is that part of the rules? I'm not too sure. We've never seen anything like this before. Unbelievable scenes, unbelievable scenes in Cozumel, the brownie brothers are being all but it's not by way of celebration. Henry Schoo Mons celebrating. He's going to win this race in Cozumel out of nowhere, But we have to be concerned about the health of Jonathan Brownlee and they're not even on the final stretch yet. Scoon wins in Cozumel. The brothers are coming home arm in arm to finish in 2nd and 3rd, but Johnny can hardly stand and Alistair is having to drag him across the line and pushing him home, pushing him home for second. Johnny finishes in second. Goodness me. What an Incredibles conclusion here in Cozumel. So I want you to think whilst uh whilst you listen to me for the next couple of minutes is what you would do if you were the medic in that situation or indeed a bystander with a little bit of medical knowledge. If you saw someone waving around the course like Jonny Brownlee was there. Uh So what we're going to talk about in this uh in this lecture is exertion associated collapse. Uh And uh in order to have that, then clearly, you need to exert yourself. And one of the most common forms of exertion is running. But when I say running, I mean, all sorts of exertionally activity. So what happens when you get hot? Because the bottom line is when you are exercising, your muscles produce an awful lot of heat and that heat needs to be got rid of because a certain degree of, of heat is good for your muscles. E your muscles probably work best when they're about 38.5 degrees centigrade. But as you go higher than that effects start to happen on the rest of the body, which is not necessarily good for you. So you need to dissipate a fair amount of that heat that's produced by your muscles. So you're central receptors, pick up the fact that your body is getting hot. Your muscles are producing loads of heat and your blood's getting warm. So you're central receptors signal the hypothalamus. Your hypothalamus is like your thermostat. Uh And that causes you to vasodilate uh to send blood to the periphery. And if you're fit and anything that has red brackets around it on this slide show occurs when you or improves when you are fitter. So if you're fit, you increase your cardiac output, okay, you also translate, translocated all of that blood to the periphery. If you can't increase your cardiac output, you can't trans locate your blood to your periphery. Uh and you increase your heat loss via sweating. So you're sweating mechanisms are upregulated. Uh And the fitter, you are the more climatized. You are the better you get at sweating. You also hyperventilate. That's not a huge problem, but, but it does cause problems with things like cramps. And if you blow off your co two, obviously, you become vasoconstricted, which is not what you want to do when you're trying to vasodilator uh and get rid of body heat. So the bottom line is when you're exercising, you want a little bit of heat in your muscles, but you don't want too much. Otherwise you start to damage your other systems. Uh and your, your heat, excess heat is not good for these areas. So it's not good for your gut. When we get hot, when we trans locate our blood to the periphery, one of the areas that loses its blood supply is the gut. So the hotter you get, the more blood is moved to the periphery, the less you can absorbed from your gut. So the fluid that you drink just sits around and swells around. But worse than that, if you lose your blood supply to your gut, you get translocation of the toxins out of your gut into the blood stream, which is bad. It affects your liver. Your liver starts to cook and basically your organs do start to cook and your brain starts to cook. Uh and the bit of your brain that's most sensitive to heat is your cerebral belem. So think about what Johnny was up to their, he's weaving all over the road. He was a tax sick. His cerebellum was probably affected because he couldn't lose the amount of heat that his muscles were generating. So people going back to the subject of the, of the lecture, people are collapse for all sorts of different reasons. Clearly, a large proportion of those collapsed through exertion or heat illness. So, E H I, we call that a small subset of those have the life threatening condition, which is exertionally heat stroke. Uh and will differentiate those right now, right up front. How do we differentiate E H I from E H S? Well, in both conditions, your core body temperature goes up but you get neurological uh signs and symptoms with exertion or heat stroke that you don't get with exertion or heat injury. So your heat stroke, patient's are confused uh wandering all over the place, a toxic etcetera, etcetera. Other things that cause you to collapse in the heat. Well, exhaustion including postural hypertension. So you're trying to trans locate all of that blood to your peripheries, you lose the blood supply to your brain, you feel faint, you collapse, okay. So, exhaustion cause you to fall, fall over. And then there are some smaller but very, very important cause is exercise associated hyponatremia when your sodium levels get lower and lower and lower over the course of activity. And this only happens with endurance related activity. So it usually happens when people have been exercising. Generally for four hours or more. So, it's your, it's your fun, rather fun runners in the marathon. Okay. You have been out on the course for 56 hours, just drinking loads and loads of water uh and making themselves hyponatremic, sudden cardiac death. So some people have sudden cardiac death. So a rhythm, a genic, a rhythm, a a arrhythmias uh is probably the biggest cause but remembers to check for a pulse when people collapse in the heat. And then the other subset is probably something that most of you have never ever heard of, which is called exertionally collapse associated with sickle cell trait. Uh And it's something that's become more on the radar uh in, in recent times because of a few unexpected deaths in us and UK military recruits. Um And the, and the common feature is a sickle cell trait. So they're the causes of exercise associated collapses, probably others. And that's represented by the pink box. But those are the main causes that we're going to talk about these. So who's at risk from collapsing in associate in association with exercise. So, uh at the very old are probably most at risk and the very, very young, although they don't tend to exert themselves to their max, people who are poorly acclimatized. If you're going to a hot climate, you really need to be well, acclimatized them, you're not acclimatized. Uh And this person, uh the in the picture is definitely not acclimatized because he has got heat rash, which is caused by, uh, sebum filling all the sweat glands and so his sweat glands aren't working. Uh, and so he's poorly acclimatized. He's also maybe got a higher BM I than he should have, but he's poorly acclimatized. His sweat glands aren't working so he is much, much more risk of getting a heat injury. People on certain types of medications and the medications that make you more at risk of uh exertion associated collapse or uh risk in the heat tend to be the anti drugs. So, anti epileptics, anti histamines, anti hypertensives, uh but also things like beta blockers and other cardiac medications, ace inhibitors, etcetera. If you're otherwise a little bit poorly, you're more at risk of collapse. So if you're fighting a flu like illness and you're working at near your vo two max, you're more likely to collapse. Unfortunately, if you've got a little bit of adipose tissue, you're not so good in the heat and you're not so resilient to exercise in a warm environment. Clearly, you have protection in a colder environment. Uh but in a warm environment, you are more at risk, you're not wearing the right clothing, not come back to that in a moment. And if you're sickle cell trait, again, small, small print stuff, but important, not to forget, probably the biggest risk factor though, of collapsing in the heat is through dehydration. If you're dehydrated, you're increasing your risk significantly So the key to most things in medicine is prevention. So if you uh if you mitigate uh for things, especially an environmental illness is uh you can do an awful lot to make your trip and your life a lot easier and also make things much better for your potential patient's. So we're gonna talk a little bit about prevention and we're gonna talk a little bit of management about management of exertion associated collapse. So in the military, we do a lot on prevention, uh heat illness and heat injury is very, very important for us. And we have policy that guides us. So we have some policy that looks at prevention and we have some policy that looks at management. Uh and the policy that looks at prevention is all tied up in the health and safety policy, which is J S P 375. Uh Chapter 41 looks at heat illness prevention, okay. And this is very, very much a command responsibility. So this sort of stuff falls down to the expedition leader as well as the expedition medic. The expedition leader needs to be aware of uh things that can go wrong in the heat and mitigate for them. The good thing about heat and exercise in the heat or in a temperate climate is that we have the ability to mitigate physiologically. We all whether we like it or not and whether we think it or not, we all share about 98% of the genome of the chimpanzee were inherently able to adapt to a warm and hot climate. If we just give our body time, we're not so physiologically able to adapt to a cold environment. And we need to rely on our behavior and what clothes we wear in the shelter we take. But we were designed to operate in uh in the heat. And so we can inherently acclimatize to the strains and stresses that we face in the heat. But we come from a temperate climate and we've got used to living in the, in the cold winters of the UK. We need to acclimatize that warm environment and we need to give our body time to acclimatize and it takes 2 to 3 weeks and it occurs with exercise. Now, we haven't always got time to build in 2 to 3 weeks into our expedition itineraries or wilderness travel or wherever we're going and let's face it. Most of us like going to warm climates. So we need to try and do a bit of this before we go. You go back to my, one of my first slides, there were those red bracketed features of what happens when you get hot. Now, general fitness will increase your cardiac output will increase your ability to sweat. So being fit is good and is protective against exercise, associated collapse and heat injury in particular. But there are other things that we, we can do. Uh these are they? So we need to exercise, uh, an idea. We need to exercise in a warm environment. So, if you've got pots of pots of cash or a company behind you, you can go to the labs, uh, kinetic run in farmer and getting a heat chamber and put a thermistor up your bottom and walk on a treadmill for an hour. Get your body temperature up and get used to exercising in a hot environment in the kit that you're going to wear. And this was me before I went and did the marathon disable uh several years ago. Now when I was fit and motivated to do such crazy things. Uh and I jumped on the back of James Cracknell hiring the chamber for the Discovery Channel for his documentary of him doing the marathon disciple in the same year that I did it clearly, he did a lot quicker and a lot better than I did. But I was able to benefit from his time in the chamber and I'd nip on the running machine after he'd been in doing his filming. But if you've got lots of money or you want to keep it simple, then go out for long runs at sort of uh 50% more than your your baseline heart rate uh for long, long periods of time. And where bin bag to create a humid environment around your body, which is encourages your body to sweat, increase. It's cardiac output, et cetera, et cetera. Okay. If you don't want to look silly running around in a bin bag, there are other things that you can do. And actually if you take, if you go for a normal run in, in temperate conditions, not in the freezing cold of winter, but you get, you get your body temperature up a bit and then you get into a bath, uh and a hot bath. The hottest bath you can really tolerate, okay. Usually we get into a bath and it's about 38 degrees. Get into a bath of 42 43 degrees. It says 40 on here. But get in the hottest bath that you can tolerate up to your neck directly after you've been running. Uh and stay in that bath for an hour and you will increase your performance by 5% if you do that for six or seven days in a row. So on the days that I had shifts where I couldn't go on the, in the in the chamber on the back of James Cracknell um on in, in my sort of preamble to the marathon D Sabila. I did this regime and it just keeps your acclimatization ticking over. And clearly, it's a lot more cost effective. What we're trying to do by acclimatizing is make our body better at sweating. So not only do we want to produce lots and lots of fluid in our sweat, but we want to decrease the amount of salt that's lost in our sweat. So we want to make it more dilute, more sweat, more dilute because the conduction of heat through water is about 20 to 25 times greater than that in a row. So we want our body to be wet and if our body is wet, we can lose loads and loads of sweat more quickly. Okay. So most sportsman that you'll see and sports women will sweat an awful lot and if they can't sweat or they're sweating so quickly because it's so hot, you will see runners pouring water over their bodies. That is both to cool them down and to cool their brains and cool their necks and cool, they're sort of blood supply going to the brain, but it's also to make their body wet. So they sweat more. You want to get your clothing and your footwear, right? So if you're going to extreme environments, I I e the desert, you want to run in the desert or walk in the desert with thick soled shoes because you don't want the ground to radiate heat to you or to conduct heat to you. So you want insulated footwear. So these trainers that I wore when I was doing the mds were had souls that were an inch, inch and a half thick, much, much thicker than my sort of regular running shoes that I would go running in the UK. Simple things make huge differences. So the color of your hat makes a huge difference. So if you wear a dark colored hat because you think it looks cool or you think it matches your running shorts or whatever and it's dark, it will absorb, it will absorb far more heat from the sun. Whereas if you wear a light colored hat, uh, like the, the chap down in the bottom, right? Uh, then you will reflect that heat away from your head so your head won't get so hot. Um So simple things make a big difference. Avoid sunburn, okay. Not only is it bad for your skin, but your grandchildren will stick their tongue out at you, but it's also really bad for you in the short term as well. So sunburn is painful as we all know. But the biggest problem with sunburn actually from an exercise perspective is you burn your sweat glands and sweat follicles. And so even when your son burners got better, your swept follicles haven't and you remain at risk for significant heat injury and collapse for three weeks after you've had the summer. So prevent it, encourage your people not to get sun burnt. So where high factor, sun group, sun cream and that's irrespective of the long term problems that we all know about. If you get a repeated sun exposure, stay hydrated, hydration would seem to be a major player in those with sickle cell trait who then go on to have eee cast. So maintain hydration prehydrate a little bit in a warm environment. Get your people to maintain the color of their urine is a light yellow and the Moroccan sands do lux paints, watch that you can pick up from being Q or home base uh and give to your people is an ideal reminder that the color of your urine should be Moroccan sand. Six, not Moroccan sands. One. Do you want it to be completely clear? Else? You get into the issues of hyponatremia. So you don't want to be getting up more than once in the night to p and you don't want to be peeing completely clear, but equally, you don't want to be peeing trickle either. So what are you gonna do when someone like Jonny collapses in front of you? So if this was just about heat injury, then we would think about all of the other causes of collapsed. So when someone, when someone collapses in front of, you got to stick to basic principles. So management of any patient in a pre hospital setting always starts with your safe approach. Uh and then your primary survey. So you're gonna address things in turn. So you don't miss stuff. So you do your bog standard primary assessment. So you see A B C D E okay and that then picks up things like sudden cardiac death. So you want to be looking for a respiratory rate and feeling for a pulse pretty early on if you just assume this is heat injury and start cooling someone down and they haven't got a pulse, then you're not doing your patient's a favor. So think about the various things that can cause you to collapse in the heat and then by doing a primary survey and some other little bespoke things, we're going to exclude and be able to manage all of the above. So, uh the document on the right is what medics who are providing medical cover for the London Marathon and other endurance events across the UK are given and it covers a few, a few things which I will pray see now. So if someone collapses, especially in an expedition environment, especially if there's been a period of endurance. Having done your primary survey, you want to manage or sorry, you want to measure core body temperature, sugar, sodium and then treatment wise early stage during the primary survey. If you think E cast might be a possibility then give oxygen. Now to give away with the cast is before people collapse, they generally complain of significant muscle pain, okay. So cramping muscle pain in the big muscles. So the thighs and glutes and they will get searing pain and cramping and that will be there presenting feature before they then collapse. So that is a clue that E cast might be the issue. Ideally, if you're gonna measure temperature, it should be a rectal temperature. Okay. The gold standard temperature is esophageal temperature, obviously we're not going to be doing that routinely in the pre hospital setting. Uh Tympanic temperature is okay. Skin temperature tends to be raised because people are very, very sweaty. So rectal temperature is the best. But that might not be possible. A you need a long thermometer. It needs to go 15 centimeters up the rectum uh to get an accurate reading. So you need a rectal temperature probe, but also it may not be appropriate in your expedition setting. Okay. So you just need to adapt to the setting that you're in. Uh and the group that you're with, basically, if the patient is hot. So they've got a, they've got a pulse first of all. Uh and you don't think it's e cast. If they are hot, you've got a cooler. Okay. Remembering that the patient's morbidity is proportional to the duration of hyperthermia. So if someone's got a body temperature of more than 40 they need to be cooled and they need to be cooled quickly. But they don't need the ice bucket challenge. The problem with cooling very, very or putting very, very cold water over the head and the upper part of the thorax is that you tend to get a vagal response, okay. And so people will collapse again and they will faint and they will vasoconstrictor. What you need to do is immerse them up to the under like us in as colder water as possible. Okay. And you have Mo Farah here having an ice bath, he's not got exertional heat injury. You want to get someone to, to cool quickly. You put them in ice cold water and you put them up to their umbilicus. Try not to get them into the water above the level of the heart or get their face very, very cold. Else you're likely to, uh, to give them a vagal response and you want to cool them as quickly as possible, aiming for sort of 0.15 degrees per minute and you want to cool them until their body temperature's 38.5. At which point you take them out the cold water and dry them off and let them do the rest of the cooling in their own time. Because what you don't want to do is overshoot and make them hypothermic in an expedition setting. You will likely have water available unless you're running across the Sahara. So if you're in a jungle environment where heat injury is very, very common and collapse in the heat is very, very common either through exhaustion or heat, uh there's lots of water and you can get them immersed in the water. It might not be ice cold, but you can get them immersed in the water up to the level of the umbilicus, maybe a little bit of their back as well and they will cool quickly. What else do you want to do with them? Clearly, you want to stop the activity. Um get them in the shade, get the clothes off, okay, maintaining dignity, okay. So you don't have to be completely stripped off, but you want to get their kit off them uh and any protective clothing they're wearing, get it off them, get the hands, get the feet out because you lose a lot of water through your hands and your feet. You may need to control seizures, okay. Benzodiazepines and in extremist, they may need putting off to sleep. Clearly, that's not going to be possible in most instances in a pre hospital environment. But looking at a case series of exertion or heat strokes that we've had in the military, at one of our training centers, we looked at a case series of people who've got very, very, very hot and been very, very sick with low G C S S and some of them seizing uh rapid ice cold water immersion therapy has removed the need for anything further than that. So no one has had formal control of the seizures. No one has had a requirement for critical care and no one has required intubating because they've been cooled very, very quickly. If they're able, you want to rehydrate them orally. If not, you might want to give them some uh IV rehydration uh but be a little bit careful uh in and around sodium levels. If that compos mentis, I alert and orientated and can swallow and, and not confused. Give them some energy that might be in gel form or it might be sort of carbohydrate form. And then think about anything else that might need treatment. Are they otherwise unwell. Do we need to address other features and other signs and symptoms? People are hot. Do we use antipyretics? Well, not an exertion or heat injury. We don't. Okay. So what antipyretics do is they alter the set point temperature of the hypothalamus. That's not the problem in heat injury or collapse in general uh due to exertion. Okay. We want to stop their body producing heat and we don't do that with paracetamol or Ibuprofen, paracetamol is probably not going to cause any harm. But Ibuprofen given in heat injury, obviously, from your basic physiological physiology knowledge, you know that it interferes with the clotting cascade and the plotting pathway. So it may make things worse, especially if you've had a severe heat stroke and you're cooking your liver giving an antipyretic may not be doing you any favors. So stay, stay away from the antipyretics in uh patient's who've collapsed, especially associated with exertion. So what do we do in the field? So this is what we do in the jungle in the military is that if someone collapses, we we sort of pause the activity for 30 minutes. We take an initial set of observations. So covering things like have they had a seizure, rectal temperature, pulse, respiratory rate, conscious level. Have they been incontinent? Are they vomiting what's the BP? What's the glucose? Uh, and we give a little score for each of those. Uh And then we do it again at 30 minutes. And if at 30 minutes, their score is between Norton to i accumulative, they can have a graduated sort of return to activity. If they're more than three, then they go off to hospital. However, if they've had a seizure or they've had a prolonged period of loss of consciousness, initially, they wouldn't go back to activity. But if they've had full resolution, they don't need to go to hospital. Only those people who remain symptomatic at 30 minutes who need to go to hospital. Okay. Some of the others in the middle ground may need sort of resting and have a blood test at 24 hours just to check, they've not cooked themselves. But generally if they get full recovery in 30 minutes and they haven't had a seizure and they haven't had a neurological event, I a prolonged loss of consciousness, then they should be able to go back to graduated activity with caution in the expedition setting, but it's on a case by case basis. But that gives you uh some parameters. Anyone who's remained symptomatic at 30 minutes needs to go to hospital. People who go to hospital should be kept in hospital for at least 24 hours. You need to know what's happening to their liver at 24 hours. You need to know what's happening to their clotting. The temptation from hospitals that don't know about exertionally associated collapse is they see a patient whose for all intents and purposes back to normal and they discharge them okay. The liver could be cooking inside their clotting mechanisms could be failing. Their heart could be under strain. Some of the poor prognostic indicators is if you haven't cool people quick enough. So I can't stress rapid cooling enough, you're cooking your liver, that's not good. If you have a prolonged coma, that's not good. I e if you need intubating ventilating and you do a sedation, hold rapidly and it doesn't work. Um And you need to be kept asleep for, for 24 hours or more if you remain hypotensive and you don't get better with cooling or IV fluids. Or if you develop a serious acute kidney injury or hyper khalid khalid mia, lots of our patient's in our case series developed a mild AKI, but it got better at between 48 72 hours. Okay. And it was only mild. So E G F R s down to 50 or 60 not 15 or 20. So you might have to manage seizures, best management of seizures. Seizures are generally related to being hot. You want to cool them, you can't call them quick enough, then Benzos may be needed. Um subsequent to Benzos. If you've had a couple of rounds of Benzos and it's not worked, then you may need to get put the patient to sleep only in extremist. Would you ever considered? Actually? So this is sort of it to you therapy after everything else has been tried. And I only put it in there because it's mentioned in some guidelines, very, very, very small print stuff. If you're not hot, if that patient isn't hot on their initial collapse, then clearly, you've got to think that this is something else. It's not a heat injury. If a patient is not hot, then it isn't a heat injury. And it is one of the other things. So, is it E cast? Well, as I said, cramping leg pain, these are the sorts of things that you would need to think about as a precursor for E cast. You're gonna give these people oh to you know, some IV fluids and then you're going to test them for sickle cell trait. Okay. So you're basically gonna treat them like you would a sickler. So high flow oxygen give them to IV fluids if someone had a sudden cardiac event and you're resuscitated them and clearly you need to do an E C G and you think might see things like an epsilon wave. So in an epsilon, Wavin V one. So that's the E C G there on the left hand side, it's a bit small but it's a little uptick uh after the R wave, a little uptick. Uh and that's maybe a sign of a rhythm, a genic, right, ventricular cardio myopathy, there are other things that cause you to have sort of the sudden cardiac death picture. And Hokum is one of those hyper obstructive cardi um hypertrophic obstructive cardiomyopathy. And the SCG on the right uh is, is suspicious for that with those Q waves, uh sort of lateral leads in a young person. So if someone has had a sort of perry sudden cardiac death or they've actually lost their outputs, they need EKGs, they need echoes. They need an ICD, they clearly need to go to a, to a cardiac unit. And if you suspect exercise associated hyponatremia. So remembering prolonged endurance activity, they need their electrolytes checked. They need this sodium measured and they need that sodium replacing uh and that sodium can be replaced as quickly as it was lost. So we get very used to warming hypothermic long like patient's in our emergency departments, we warn them slowly. We replace low chronic low sodiums slowly. Generally in medicine, if you replace things at the speed that they were lost, then you're doing fine. So in heat injury, people get hot very quickly. So you cool and very quickly. In heat injury, people tend to lose their sodium reasonably quickly. So you want to replace it reasonably quickly. So in summary exercise associated collapse and thinking about the heat related problems, prevention is much better than cure, make your life easy as the expedition medic do some of those prevention things make sure people are acclimatized, know what medications people are taking, make sure people are hydrated. Uh make sure people haven't got into current illnesses and then exerting themselves at their maximum level. Remember, we can all acclimatize to the heat. Okay. We're all chimpanzees. We can all do well in the heat. If someone collapses, check their temperature, that is the absolute key that differentiates whether someone's got heat injury or whether someone's got another cause, check their sugar, make sure they're not hyperglycemic. Check their sodium, give them some oxygen. If you think he cast is an issue. If they're hot, cool them rapidly, we want to be cooling these people as rapidly as possible, but we don't want to give them the ice bucket challenge. We don't want to make them vagal. And if you want a little tool, then the exertion or heat injury cards, triage guide ongoing management. What you're going to do with the patient's? That is a useful tool. Okay. But remember every case is slightly different. I hope that's a useful summary. Uh I hope that you enjoy the sort of face to face element of your endeavor course. And if there are any questions, I'm sure Boo will come back to me with them and I will do my best to answer them. Thank you very much for taking the time to watch this.