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Good evening. Everyone would like to walk about Doctor Vogel. And this evening, he's going to speak to us about acid and basis. So Doctor Vogel over to you. Okay. See, they get a screen. Uh, can you see that? Uh, yes, I can. Yes, we can see it here. Okay, great. Okay. So Hi, I'm Dr John Google. Uh, and I haven't changed since the last six letters I gave you. So, um, tonight we're gonna talk about acid base balance. I put in I t It's not just a night to you, and it's a subject that I find a lot of people think they know a lot about. But in fact, when you ask him to under they understand it truly understand it. The answer is probably No. Okay, so we're gonna start with a clinical case. True stories. These and I don't expect you to answer this question just to think about it as we go through it. And then the end will be we'll go through it again together. So this is a true story about a woman who was 62 years old, who arrived in our hospitals exit emergency department four days prior to discharge from a tertiary center with a diagnosis of severe inflammatory bowel disease. And he had a discharging a massively discharging fistula. I'm surprised they didn't discharge. They did. And this is the blood. Guess he was unwell. This is a blood gas that was shown to me as I was called from the eye to you down to the end. So just take a second to look at that and think about it and we'll try and work out what is the cause And also how you would treat this if it all Okay, so this is an outline of what we're gonna talk about tonight. So first of all, the big question is, what's the big deal? Why worry about acid base problems? Then we're gonna talk about reculture additional methods, these the things that we've all learned and I was brought up with and I still use. But they've got some drawbacks and they're not quite satisfactory and explaining the mechanisms that go on and these mechanisms could be important when you get complicated acid baseball so you can get away with the usual traditional methods most of the time. But sometimes you need something a bit more in depth and the the model we're gonna plunge into. It's called the Stewarts Physical Chemical Moment or Physical Chemical Method. It's ah, method described by a Canadian physical chemists. He's not a doctor, not a medical doctor. Sadly passed away recently. Almost everybody who deals with complicated, acid based problems agrees that this is the best technique. However, the problem, the drawback with it is that there's a lot of maths involved and a lot of people believe, or a lot of people I know, including myself, for not very good at math. And so, um, they turned to ignore this technique. So I'm gonna try and explain to you tonight without using Mess. Well, we'll try and we'll see how we get on. Now. I'm gonna go through some clinical examples of how we use these this method. So number one what? I'm worried. What's the big deal about acid base problems? Doesn't matter. So this is, um, this is a made up case of somebody who has a metal ball. Casodex is with the base deficit of about five, and I'm gonna have to interrupt myself to explain, to find some term. So what? Acid base is made unnecessarily complicated, so a base excess is a negative based deficit and vice versa. So some people use the term based excess. Others use the term based deficit. That just makes things much more complicated. It needs to be, so I'm going to stick to base deficit. So based deficit five is a base excess of minus five. OK, start to be confusing, but that's the way the world works. So let's look at the cause of this relatively mild metabolic acidosis. And let's look at the risk of death, because at the end of the day, that's what really counts the risk of death. Does it make it more likely to die or not? If you have an increase of lactic acid and that would, um, cause a base deficit of five in the middle acidosis, your risk of death is about two times you're twice is likely to die if you get what people call today. Ah, hyper chlorine make acidosis, and I hope to demonstrate to you that that is a misnomer and this is a little bit controversial. Open up, too controversial. As far as I'm concerned, Almost other studies have seen say, the same thing. There's no change in mortality, so people have tried to find, you know, closes of harm. But there really isn't a lot of evidence that hyper clearly make acidosis. UM, is really particularly harmful. Where as lactic acidosis is, the problem is that the basic steps and actually the second best it's important. The problem is the hydrogen ion or the pH disturbance with an acid base problem is a symptom of underlying disease. Now, unless we're talking about extremely extreme, um, variations in acid based problems, Um, we're basically talking about something that's causing This is the cause of this acid basis, German says. The underlying disease. So it's a PSA. That's the problem. It's not usually the acid base problem per se, but what causes it. You coming? It's an example. Sit back up what I'm saying. So this was a study done a long time ago in the 19 nineties, uh, which is a new internal medicine, and they tried something called D. C. A dichloroacetate, and it's a It's a compound that increases your cells utilization of glucose to perform oxidative fuss relation. So basically reduces your lactate level. So people think, Oh, lactic acidosis is terrible. We got rid of lactate. Relax. Take acid by using DC A or dialysis, for example. You think? Okay, well, I've solved my problem. Well, maybe not. So this is a comparison of DC A dichloroacetate compared to placebo. Okay. And as you can see, DC a definitely reduces like tape dramatically. We'll see about doesn't. Okay, so it does what it says on the 10. We'll peek. Well, DC, it increases your pH, which is what you expect if you have ah, low pH because of a metabolic acidosis. So again, it does what it's supposed to do. We'll see about doesn't. What about mortality? Placebo? DCA. No difference in mortality. This just illustrates the fact that removing the lactic acid will improve your ph. But it will make a difference to your alk. Um, because the cause of the lactic acid is what's killing you. And I've seen this load of times with my your your colleagues who say this person has ah, lactic acidosis. Let's put him on dialysis. And I said, you're wasting your time. Dialysis has never been proven to improve your mortality by removing lactic acid. Okay, it's that confirms it about risperidone acidosis, and this is a really old study from 1959 and they looked at patients who were kept oxygenated. It's Z experimental technique, and it kept them apneic for up to 55 minutes, and they created a risperidone acidosis. And guess what they found Welt tolerated in normal subjects. Without an oxy, it's This is just a pure retention of two. Look at the steel two levels. Now those are millimeters of mercury. So you divide by 7.5. You get an idea of how high that those are. And the pictures were really low 6.7, for example. And the reason I I'm very sensitive to the studies because I took a year off clinical work to work in the French MRC and we were testing the respiratory depressant drugs of various various drugs. We're using a technique where you're rebuilding your own. So, too, we had eight eight volunteers. I was one of my own volunteers, and all the text books would save your T 02 goes above, say, 10 killed, passed counts. You're gonna fall into a coma and you'll die horrible death. I can promise you something are are are so Tuesday the Order 20 and Killer Killer Pascal's and there's no way you're gonna fall into a coma. Your your head's pumping, your heart's pumping, you feel like your head's would have explode. You can feel your vessels dilating, but there was no way you're going to a coma. I asked the question. Maybe it's the person who is a ton did and then raise their so two, as opposed to go to cause him to be attended again. These are normal subjects, as they were in my study, but there was no way I was going to a coma in levels that all the textbooks say you'll be in a coma. That's not true. We didn't see, so that's the traditional method. So I'm gonna go over the stuff you probably have learned ready and are very, very useful. When I'm I use them all the time. Before we do that, we've got to start with some very simple definition Now. There are a lot of definitions about how do you define Ph and acid base? So I'm gonna ask you to forget everything you've learned in the past and just give me your brain and I'm gonna try and wipe it clean like a sleep like a blackboard and trying to write my own story on it. Okay, so, first definition, what is a pH? Anybody would, I guess, a log arrhythmic concentration off protons. You're almost 100% right there by the endo. It's the it's a negative log of you're so basically what it is is a fancy way of quantifying the number of hydrogen you got. It's it's just the way of quantifying something. And, you know, you could argue that. Why is it just something you could have done? Ph of sodium you wanted to. So it's just a fancy quantification of hydradenitis expresses and negative lover. So that means the higher the number, the smaller the number of hydrocodone and you have so the lower the number. So if you're seven p, it goes from 7.4 to 7.5, you have fewer hydrogen ion. It goes from 7.4 to 7.2. You have more. So it's the opposite. So it goes up, everything goes down okay. Secondly, what's an acid now? I won't ask you to guess cause I want to give you my definition. It's very simple. It's when you have more hydrogen ion. More plus is, you know it's minus okay. Very simple. What's a base? Well, yes, it's the opposite. It's You have more minus compared to eight, Plus really simple definition. What's a strong electrolytes? Does anybody here like spaghetti? I assume you don't have to answer that because I seen the answer is yes. And if you know how to make spaghetti, probably what you have to do is you have to add a lot of salt to your boiling water. You don't want to solve the spaghetti afternoon you got a oh may almost blood boil and salt water so they say, when they're if you're Italian and urine expert spaghetti maker. So let's say, for argument's sake, I'm making spaghetti tonight and I take a handful. I got 5 g of salt, an ACL, and I throw into the bowling water. How much salt is in the boiling water? Very nearly All of it is very soluble, right? So the answer is no. There's no salt boiling water because salt is any CEO, and it's strong electrolytes, so totally dissociates. There's an A plus on a C L minus, but there's no n a c e o. So there's no salt in boiling water. It's a strong electrolyte, completely associates. There's no parent compound present because it's totally dissociated. So what's a weak electrolyte? Well, that's one where you have, say, compound A B. Place it in water is not to be boiling water and you'll have a You have B and you have some. Maybe so it's partially associate. So it's very simple terms. You have to understand it. But if, by the way, if anybody is lost on one of these slides, please stop me because everything builds on the next slide. So if you don't get something, you're gonna be lost for the rest of the lecture So far, I think it's relatively soon. So traditional pro case. We're going to do them first quickly. We have the bark bicarbonate centered approach and the base deficit or excess approach. So what about drinking a protest of the bicarbonate center called the head? Understand? Hassleback, uh, approved. So this is my old friend. We called it the Devenport diagram. I was brought up on this, um, and I still used it routinely, and It's got the peak on the X axis. You have the bicarbonate on the Y axis and you have that ground line, which is what your P 02 is. As long as it's stable, it's 5.3. If you increase your decreased earpiece to go to your brown line trips along the blue line and you'll see what I mean in the second. So your normal values, this someone is totally normal. They have a peak of 7.4, and they have a bicarbonate of 24. That's normal. Okay, now let's see. Some of you has Medlock acidosis. So let's say, for argument's sake, you have somebody on a ventilator. So you're controlling their PCOS, too, so it doesn't look very at all, and they suddenly get, um, I know they have a diabetic ketoacidosis. So what's going to happen? You're going to drop on that brown line because your C to stays the same, and your pH is in the drop dramatically to 7.24, as is your bicarbonate. So it's quite steep that brown line, so bicarbonate drops dramatically. And of course, the opposite occurs. If you have a minimal calculosis with a fixed. So too. Now, let's see, you have a pure risperidone, every acidosis or alkalosis. So the metabolic component is totally negated. What happens if you have somebody who breeze? Um, who has seemed to that increases. So the example I gave you earlier when you did a study Where your breathing your own so too. And presumably your metabolic component is is the same. Well, you're going to have an increase in oh two. And because you're on that relatively small sloped blue line, you will get a slight increase in bicarbonate. But you'll get a dramatic drop in Ph. On the other hand, if I were to hyperventilate, you're going to get a slight drop in bicarbonate because the blue lines Not very, Steven, but you're gonna get a very a marked increase in peace in a p h. So that's those are fixed and somewhat abnormal conditions. Usually you do 20 compensate. Now let's say you have somebody who has diabetic ketoacidosis. If you see someone with diabetic ketoacidosis, they have a sucker characteristic way of breathing. We even have a name for it to you. Any idea what the name is? Smoke raising? Yes, very very good. I mean, it must be pretty the priest, distinctive to have a name put to it the way you breathe, but you're you're you're puffing away like a train. So what happens now When you when you have a disturbance, your your body tries to compensate by returning your pH towards normal and you never get to normal. You get towards um So let's look at this. Let's say you have somebody who has a metabolic acidosis. So, as we said earlier, you get a dramatic drop in bicarbonate and you're going to now try and hyperventilate to compensate for that middle acidosis. So you're gonna shift your round line over to the right and you're going to start going back towards normal. Ph. And because you got that slight sloped blue line, you're gonna get a further drop slight drop by corporate. And now let's see, you have somebody who has a respiratory acidosis, and you're going to see what happens to them if they have somebody who has COPD and they have a new acute respiratory distress and they have acute respiratory acidosis. What's gonna happen? They're going to increase or so to. But now you're going to try and compensate by bringing your little dot back to the normal pH From what you gonna do, your gonna increase your bicarbonate? It's going. You're peak is going back towards normal. It won't go back completely to it, but it will go towards it. And because it takes a while for the Risperdal, a component of compensate that'll take a couple of days. You treat 24 48 to 72 hours. Unlike previous example, where if you have a metabolic acidosis, your spirit e response is immediate. So this takes a while. It takes 48 to 72 hours. Now this has implications that are important. So here's a typical clinical case. I used to get all the time I get a phone call. We have a 62 year old man upstairs with COPD and his worsening. It's not worsening Dyspnea. He's breathless, right? Start calls you because you're the eye to duck. And he's worried about the arterial blood. Yes, Okay, that's all he talks about. The saturation is 93%. All right, But what worries him is a PCO to is 7.2 normal being 5.5 are you worried by this? Yeah. Are you? You're already home. Any of the teams? Well, I think it depends on number things, but I'd like to know Is a bit more information? Blood guest? Any idea what more information I would like? Uh, he Asian bicarbonate? Yeah. Great. Absolutely. I want to know. So his pa could say 7.37. And his bicarbonate is 35. That tells me he's taken it least 48 hours to toe have this middle compensation, which means is probably used to it. You may have acute on chronic, but, you know, it tells me that this man will woman is is it's got a very strong chronic component to it. Now I want to know a lot more about this case aside and just apply. Guess obviously, because he may be struggling when he breathes. I don't know if he's using accessory muscles, etcetera, etcetera. And by the way, if you ever get an asthmatic who has a normal PCO to, I would get very worried because usually asthmatics in a crisis are supposed to have a low CO2. It's It's normal. That means they're getting exhausted. They're on their way up and they're gonna have a respiratory arrest very soon. So again, you got to take it the croup context. But that's the kind of thing you wanna ask about. You have a high. So two is What's the ph in? What's the what's the by car that tells you they've been compensating over time or not? The second approach is the base deficit approach. We'll forget the excess. I find that stupid trying to make things up, you know, go back to front. So what is it? What is the stiffness face deficit is, um is a titration. You take your sample, you're only looking at the middle component, and you are going to use this InVitro and you're going to titrate strong alkali or strong acid depending on the ph to bring it back to a normal E h. Okay, so if you have a, uh uh, a sample, it's got a ph of 7.1. You're gonna add alkali until you bring that settled back to 7.4, all right. And the mount you have to titrate will tell you how much how much your deficit there is. But the key thing is This's when the CEO to in your lab of conditions are normalized. So you're removing the respiratory components, only the middle component, the problem with base deficit. And this is something that's not often appreciated. It's an average of what can be opposing influences. You can have somebody who has a stick influences at the same time they have out Connecticut influences. And what you're looking at is an average. So, for example, if I have my my left foot in boiling water and I have my wife put in freezing water with ice cubes and you say to me, What's your average temperature? I say, Well, it's 37. Oh, everything's fine, right? No, Um, I think that's obvious. The second problem with the base deficit, it doesn't explain the cost. Um, quick question, Doctor, when you say amounts needed, like, what kind of you know, Are we talking when you say, like, amount of alcohol, I needed to risk or well, so if you say your base deficit, it's fine to be five. I guess the five million holes I get up, you call me out there, but yeah, based deficit of five is a good question. Um Okay, so here's, ah, critical case. Someone's got multiple trauma. They have a RDS and sepsis. They're cute too. Is 14.5 Your pH is 7.3 to those are normal. That was just in case someone isn't familiar. So two is normal. The bicarbonate is a little bit low. They're based. Deficit is four when it should be between plus and minus two. Is there an acid base disturbance? And is it severe? Is it mild? Yeah, I think you stay looking at that. It's a It's a mile mile. Metabolic acidosis, wouldn't you? It was great. Yeah, I said, what kind of? Okay, let's look at this in a graphic form and you'll understand how I drive this graph at the end of this talk because we're gonna go through this using Stewart smoke. So those are the numbers. I just gave you some things that most people don't even bother looking at, which are big, big players in acid base problems. You want to know what the sodium the chloride, the albumin and lactic acid is now a lot of gas. It used to be We used to guess what it was because we didn't have lactic acid essays in our blood gas machines. But now we do so you don't have to guess at this and more. So here are the values, and don't worry about looking at them in detail yet. I'm just a graphics out and you'll see very clearly. This is a graph you're gonna see over and over again. You have your line of unity. Any alkalinity effect is going to be above that line, and any acidic effect is going to be below the lung. So there's your so we call. We will explain this in a second with sodium chloride effect. It's all clinic the albumin effect. Again. There's a low albumin and elements and acid, so the less acid you have, the more alcoholic your effect is. So you got two out Connecticut fix. You have a massive lactic acid stomach because you have like to guess which is massive. And 18, you have something that's done. Measure that could be anything it could be. So Furik acid. Four mcg acid. If you have taken a gal call overdose, if it's aspirin or if it's ketoacidosis something, we haven't made it. Okay, so that's the on measured That's the mystery. Why on which isn't very great in this case. And there's your base deficit of four. So we go back to what we said. Initially, they step. Is it a four? No big deal, right? Well, you have missed all this because, as we said, you have 1 ft in boiling water on 1 ft in freezing water and on averaging up too far off normal. So we've totally misunderstood that severity of this acid based disturbance. So one of the problems with traditional approach is and they're useful. And I used them all the time. I was work on them, and I still like old friends. Most clinicians, if you talk to them honestly and in detail, can't teach you acid base because they don't understand it. And I have to be the first to raise my hand because for years I thought I understood it. One day someone asked me a question, and I've been doing it for years and years, and I realized, I can't just I can't explain this cause I don't understand it. I don't know how to use it, using the rules of thumb your wrist sticks. Recall that, but I couldn't really explain it. I didn't deeply understood it. We understand it. Sorry. And so I had a friend who was a Fulbright scholar and chemistry, and I asked her to help me explain this using Stewart's model without Mass. And we worked on together for about four months, and they finally came up with approach. It works quite well, but you'll have to tell me if that's true it up. So hopefully at the end of this lecture, you will understand the chemistry behind this will help you understand why certain things happen in some things don't have. There's very little quantitative data on the patient's acid base status, using traditional methods, protein and electrolytes and not even looked at, which is unbelievable because they're the biggest players. In some ways, there's no dice diagnostic, very little diagnostic information, and we just saw you have major disturbance is hidden. What looks like pretty normalish acid base, uh, results. So now we're going to plunge into Stewart's physical chemical method, and I can promise you, if you understand this, you'll be a rare breed because so many even senior people will say to you, Oh, it's too complicated because there's too many, Massive. All And there, Right. But we're gonna try and understand this we're using. That's so Stuart's physical chemical approach requires you to understand some very basic concepts. You have to understand the physical chemistry, and we're gonna bring you back to high school chemistry to some degree, the physical chemistry of pure water all to do with modification of dissociation of water. You're gonna add strong ions, member the sultan, the boiling water we're making spaghetti. You gonna add strong electrolytes, You're gonna add week electrolytes. We guys gonna add so, too, and we're gonna then try and you sound deductive. I put the X across mathematical because most of the studies most the books explain Stewart's use a lot of mass. We're going to try and use it without the mass, so you have to bear with me on this. But before we had started, let's try get some perspective on some of the elements we're going to be looking at. So, um, we're gonna start comparing some of the elements. You see an extra cellular fluid in serum essentially, and by the way, we're talking now about extra cellular acid. Baseball is not interested in here. So before we start, Let's, um you probably don't remember this, but I remember the days when we didn't have in Europe, the euro. So if you were to drive around, you're trying to say I'd like to buy a book. Swagged. You're a BMW. Whatever car you want, let's see. Have Volkswagen golf. Okay, that's a car I drive. So that's, uh, that makes it easier for me if I were to France in those days. I have to look at cost in French Franks. I go to Germany that being Deutschmarks, millions and millions of lira, you go to college guilders and it was so important was impossible to prepare. You know, apples and apples. The euro came along. One of the advantages of the euro is that you go to all these countries and you've got the same currency so you can prepare them. So what we're going to do now is look at these elements. We're going to use the same currency, the same quantitative measurement. Okay, so one leader of plasma contains 40 nanomol of hydrogen ion. If your PH is 7.4, if you pee into some 0.0, you have 100 emulsion. Okay, that's for your own interests. But a peak of 7.4 that's a normal pH has got 40 nanomol of hydration, eyes eight plus sodium. If you take the normal value on the labs, uh, very, but I'm going to just use some simple values. If the sodium is 140 millimoles that equals, don't forget, we're trying to convert everything to the same quantitative currency. We're gonna have 140 million in animals. For a leader, that's equals 140 million holes of sodium. If we wanted the cabinet waters in a leader of plasma, you probably don't know this. You've got 55 billion no mammals for a leader of water. So we go from 55 billion of water, 140 million of sodium and 40 miserable in animals of hydrogen. Er, it's kind of amazing when you think of the biological impact that hydrogen nines have relative to this other elements. Or so sit Stewart. It doesn't make a look. No, uh, no dispute from that. Merely so before we start, we've gotta understand a couple of very fundamental principles. Toe Understand? Stewart's model, and they're really to be simple. There's one is the conservation of mass. So in a closed system, the sum total of substance to the equity So Lucian has to be a constant unless you added removed from the outside. So, like, say album and could be created by your liver or could be removed. But if you have an adequate solution, that associates the A plus in which minus, if one goes up, one has to go down to to maintain that constant. Okay, it's the product of HPI. US in a week minus has got to be a constant. So if you associate water into a person which minus, they're equal, if one then subsequent goes up, the other ones got to go down to maintain that constant. All right, does that? Is that everybody happy with that? Who's okay? Good. So increase of one least decrease for the the second is electoral neutral. You've gotta have the same number in your extracellular fluid of hydro of positive and negative, my aunts. Okay, you've got to be the same. If not that you would be a battery. And unless you glow in the dark, um, then you've got the same number of positive and negative charges. Okay, those are the two months of masks electron. You travel everything we talked about Scott and respect those two. Those two principles. Now let's talk about water and how it's associates again. This goes back a little bit too high school, high school chemistry. But it's absolutely it's a water becomes age plus in a week minus no. If you remember your high school chemistry, how much of that water associates to it? Plus and minus is the term, but we call the association coefficient K W. Now that's the equation that determines how much water is. Associate it now, if you recall. We just said that in a leader of plasma you have 55 billion in animals of water and you have 40 in animals of age plus, So obviously K W is absolutely minuscule compared to the amount of hydrocodone you got. So it's so small that if I were to suddenly make it a million times bigger, it would essentially make no difference. So I had a million times more. It plus is because my water's associating a million times more. I'm gonna have like itself almost 55 billion and versus a million plus is a million plus 40. So So essentially, you could say that those two are a constant, because the matter how much you drink that association called fishing is minuscule compared to the amount of the differential between water 55 billion and 80 plus, which is 40 of minimal. Is that okay with everybody? Ah, yes, Doctor. Yes. Great. And because you have to have electrical neutrality when Watered associates, you're gonna have equal amount of each person, which minus. However, if something comes in from the outside, you're gonna alter that balance, and you're gonna adjust your pulse in a way to minus forget one goes up when goes down to the outside influences. And it's these independent variables that cause this adjustment that control acid base by influencing That's the key word. They influence the association of water. Okay, they will come clears. We build this picture there. So as we just said, all acid based states, according to Stewart's physical chemical model, result from the alterations of Association of Water. That's the key term. So let's build something that we're going to start. We're going to start making, um, a soup. All right. One of a better term. Now, the problem is this. And you'll have to indulge me here if you imagine a column of water. And it's 55 billion and you have 40 um, no animals of age plus or minus. You're gonna have a colon that's so high it's gonna go up to the stratosphere. You could have a thin membrane of explosives if I were to draw it to scale, obviously. And I do this on my computer. So the columns you're about to see are obviously nowhere even close to scale. Okay. See, you have to use your imagination. So let's look at this. So these are the we just talked about how the of various aspects of Watered association occurs in the physical chemical model. So you have association coefficient because unbelievably small, because a very, very, very small amount of take two hours associating, take, plus, you know which minus. So there's your positive charge. Couple of water, lots of lots of lots of water, right? This guy, there's your negative calm. And because the water will be dissociating into equal amounts of eight plus now it's minus. Is There's gotta be electrical neutrality. You're gonna have them equal. So there's your X plus and there's your minus and we're in balance. Easy. All right. So far, so good. Now it's add. We're going to make that spaghetti we talked about. We're gonna throw in that salt into that speed of water, that boiling water, which is water. There's your positive call. There's your negative call. And because sodium and chloride are gonna be equal because there's electoral neutrality, there's your plus from sodium. There's your chloride and you still have your water age. Plus in a week from minus. There's all your positive charges and negative charges. Arm our balance, so you're still in balance. Everything's fine. Everything works. We'll find so far. No, this is where things get interesting because of need for membrane function and osmolality to be 100% 100% honest with you. I'm not even 100 century. Why, but there's obviously somebody who's very smart out there. You can tell me why this is, but I think has to do with membrane function. You're gonna have more any plus, then seal minus. Well, by the way, one thing I want to clarify. I'm trying to make this a simple as possible, so I'm not gonna bring in all the positive irons, like potassium or the negative ions like prostate. And try to make this really simple. The big players, our sodium and chloride. So there's your positive call of water. There's your negative calm water. There was your sodium, and there's a difference from the amount of sodium chloride there's your age. Plus, there's your chloride and the difference between the sodium column and the chloride calm is a very important term. It's called the strong eye on it If rinse. That's a term we're gonna be using a lot. And it's a really important term. Strong I on difference Where the s i d? There you go. That's the difference. Treated, too. Now you have to fill that space if you like to keep the electrical neutrality respected. And so what's going to fill that space? Oh, eight minus. Okay. So it's going to influence now that association of water. So some of the supposed to be driven into order and only will come out of work number we keep that constant. So if you want to think I tend to have a tendency. That's probably very not not very healthy, but I tend to use very stupidly simple analogies. So imagine I've got a house and my house is a brand new house. I got a new attic, and there's myself, my wife and my son, and we all have stuff. We want to put it My I want to put in my books. My wife wants to put in her paintings with he paints, and my son has records. Okay, so we're gonna be fighting for the space. So first of all, you want to know how big is the space? How big is the attic to start with? So how much we got to play with? Well, the stroller and difference is the size of my act. Okay, so now I've got much more awake than I do eight plus to fill that space. Got a fill it to keep electric. You travel, itty. I have to have that space full. And it's going to be full of which months. So far. So now you can see the balance is tilted way over towards Oh, it's minus. And we said, by definition, that is an alkaline more out. More weight to minus two plus. Okay, that's a base as opposed to an acid. All right, So far, so good. Yeah. Okay, let's talk for a brief second about stolen difference. But it's very, very important. Normally and again, I'm giving you rough figures just around the figures. Different labs. They're slightly different. Let's say it's normally about 1 40. That's right, 40. So say a lab would have a normal sodium. Let's say, for argument's a 1 40 millimoles, your chloride would say be 100 million holes. The difference in 1 41 100 is 40. That's just a nine difference if you decrease your storm or indifference so suddenly you're making that attic smaller. There's less space for a way, so you're tilting the balance towards acid. Okay, so your acid, your tilted, your s your alkaline tilt. There's a lake is suddenly there's less. Oh, it was being driven back into food solution, and you're gonna be tilting the balance towards acid still alkaline. But it's less alcohol. So, for example, what would do that? Well, hyper chlorine make acidosis. Well, come on to that in a second. So if someone gives you large volumes of saline. So, for example, what is does anybody know how to make ceiling is over myself in some water, you know, inside employed. It's exactly, I mean, you could make it at home what we call normal saline, a 0.9% saline and the reason that's the most commonly used fluid in the world on this planet. It's good it's so easy to make. And so what is the strong lion difference that so much so how much sodium is and say like, so be a zero. I'm difference. Yeah, exactly. So it's 1 54 sodium 1 54 Chloride is the difference is zero. What's the stronger and difference of glucose 5% or any water Well, here Oh, is it? So if you add either lots of saline with zero strong and difference or lots and lots and lots of water because some of that water is gonna much of the most of what is going to interest of memory were told. My extra cellular acid base balance. You're going to dilute your normal, stronger and difference. You're gonna make that different smaller. You'll see in a second what I mean by that. Well, not if you increase your stolen different. So you make that space bigger. Your your your attic has gotten bigger. Suddenly you're going to feel that it was something so far and that that's something to be okay, so you're making yourself more alkaline. So say, for example, if I lose chloride, how do I do that? Well, diarrhetics will cause you to lose one sodium for two chloride, so you're losing more chloride in sodium's. You're strong and difference getting bigger. If someone has, it's the knees. A gastric tube in a circle really suck. You're going to lose more chloride. Then you're going to lose sodium again. You're going to make that strong and difference that space that attic space bigger that space is going to go with something. That's, oh, excuse me, Make them all Kalanick. Okay, so let's look at this and this way. I think that term strong and difference Sorry Hyperkalemic acidosis is a misnomer if I take a leader of extra cellular fluid and there's the normal values 1 40 for sodium, 100 for chloride, the stronger arguments of 40 and you could do the arithmetic it home. Okay, I will make you do it here, and you add a leader of saline so you're making them equal in volume. You mix them together so there's no strong and difference. We just said where you just said correctly, You mix it together. You've now got a strong I a difference of 20 sodium 1. 47 chloride 1 27. The difference is 20 tense. The space is smaller. Hence there's awake. He's going to be less, uh, less presents. You're tilting the balance away from too much awake more towards acid. You're still alkaline, but you're less alcohol. And this is what they call quote unquote a hyper chlorine. Make acidosis. If you're being absolutely correct, it's not a hyper chlorine. A cast the doses. It's a strong mind. Different spaciticity. What about if I had water? Same thing again. 1, 4100 and 40. This time I had water. Lots of water. Mix them together. You can do the mess this time of sodium chloride are gonna be different values with a strong mind difference and still be the same 20. And that will cause you to have the same relative acidosis unless you'd be less alcoholic. Okay, So just to give you an idea of what some of the commonly used IV solutions are like a sodium cried, most importantly, still learning difference in ph plasma. Well, 1 41 140 is normal, strong a difference, and ph is 7.4 saline. As we just said, it's gonna see strong and difference of zero dextrose has got a strong and difference of zero. No, Hartmann's is often proposed. Hartmann's arenas lactate. It's supposed to be used because it's more physiological because it's got a strong a difference of 28 which is closer to 40 than zero. And if any of you have ever been using PLASMALYTE. In fact, when the lady who sold us plasmalyte because we were using ringers lack tape came along to sell us plasmalyte when I was working in in the hospital, um, amazing he was He didn't even know the main theoretical benefit of plasma. I had to tell her What is it? It's got a plaza. It's got a strong a difference of 40. So it's normal. Does this make any clinical difference? I think it's zero difference. Okay, so but if you want to be a purist and you won't be very theoretical. It's got a normal, stronger in difference, unlike heart meds, which is minor minor difference. So what affects the stronger difference? Well, how about sodium bicarbonate? If someone's got an acidosis and your gifts sodium bicarbonate, how does sodium bicarbonate work? If you take into account everything we just talked about? Well, it's sodium. A stronger and and bicarbonate a week. I saying, What is my carbon? It become a C A three minus and then age plus. And no, no, h minus And, oh, two, it becomes water and see what it does it. What time? See you want to? Yeah. What happened to see her, too? No, you You hit the planet, don't you? You're the cause of global warming. Cream on you anyway, So you blow off your bicarbonate. So you're left with sodium positive ion unaccompanied by a negative iron. So you're basically increasing your stronger and difference. All right, What about if you wanted to, um, decrease your stone? A difference? Likely? I was Look that up because it's some experience. One things you could do if you want to decrease your strong and difference increases No no difference. Nothing you could do is is, um, is give him a diuretic because you'll lose chloride so bicarbonate will increase your sodium relative to buy a choroid because you're giving study on accompanied by a negative and diarrhetics will cause you a drop in cool, right, so your sodium stays relatively the same, but your chloride gets lower, so you have a bigger, stronger, different. They both do the same thing. So here's the story, that true story and, uh, white, a traumatic story. So I was not in the eye to this particular day. I was outside the eye to you and my excellent colleague, who was in a really tough spot. He had a patient who had severe bronchospasms and really severe asthma, and he was forced to intubate this person and tried to ventilate them. We try not to do that because it's often extremely difficult. Potentially. The problem is, they can't it's not. They can't get the gas, since they get high pox of usually if they can't get the guests out. And so he you give Bronco dilator, and that's always what you've got to do. But they can sometimes take a while to work. And so, while you're waiting for these Broncho dilators to work, you're trying to get this gas out, and it's not easy. I remember that. You know, you can disconnect them and listen to them, and they just go. Ah was on forever because they're slowly getting rid of this. Guess they were very, very long. We called time constant. So basically very long time, too. Get rid of the guests. They get a lot of auto peep, interesting people. And by the way, that's what kills you with asking you unless you get a pneumothorax. Kills you with the aspirin, is you get right heart failure because you have this massive intrinsic Pete, That's that's for another day. Okay, so this this was the blood gas results of his first baby. Geez, are troubled. Guess is, uh, while they're waiting for the broncho dilators to work, Ph was 6.75. So two is 22. Don't forget normal is 5.3. That's really high. Bicarbonate was not too low based. Deficit was normal. Sodium was 1 44 chloride 106. So so far, everything is pretty normal albums normal. And so that's a three. It's a pure respiratory acidosis. Everyone agrees. Yes. Okay, that was really scary. And my colleague Look at that. And he goes, Whoa, I've got to treat that. So would you correct this pH with sodium bicarbonate? No. No, because he can't blow off the product. Give that man a cigar. You're absolutely right. That was great. Good answer. But sadly, that's exactly what he did. He got so frightened that he gave 200 mils of sodium bicarbonate 8.4%. And so there's this is what the following book guess was. Peak is a little bit better, but now is go to is unrecoverable. This man's problem was he can't get rid of so two. He's got this massive load on his shoulders and to say, I've got an idea. I'm gonna make your load even heavier. Thank you. Okay, so now his bicarbonate is under, according to is under Kordell, but his Ph is a little better. Wonderful. So he was getting panicking. Any because of this lecturing, I got this sort of reputation of being some sort of acid based guru, which I'm definitely not. And so he said, What can we do now do not miss interpret. What about to say I'm not saying this is the treatment for asthma. Of course it's bronchodilators. But just so you understand the principles behind what we did, I said, You don't want to get bicarbonate. That's obvious. So we gave him a freeze might. And if you hear what that will do is we'll lower the chloride without raising the CO2. And again, I'm not saying proves, mind is the treatment of asthma. I'm not saying that, but this just to illustrate how this works and acid based environment. This eventuate corrected his pH. Um, how quickly would that work, Doctor, that would take a little while. In fact, it's interesting, because when you treat the most, I'm off the I'm not off the subject, but slightly slight, um, sidetrack. When you have people with a R. D s and your ventilating them, your goal is not to over Vince late. You cause with a call ventilator induced lung injury, and what some people do is they put them on diuretics to try and dry out that long. I personally think that's nonsense. If I smashed my elbow with a hammer and swells. You can give me divertics and get me peeing all night long because my elbows inflamed. It will decrease. I'll be driving my over. Won't go down. I don't think so. Anyway, if your lungs are inflamed, that's what they are. DS is, um you get people diarrhetics. I can't believe that's going to make them dry. Um, not dry out their lungs. What it will do, though, is it'll cause a metal bulk alkalosis, which will allow you to tolerate a respiratory acidosis secondary to gentle ventilation. So you don't eventually them so much because that's damaging once we know that. So I think that's how that's how I use it. And that's how I think it works. Okay, this is just a side. So what's the next thing we're building? A soup we talked about. Okay, we have water. We had so sodium chloride. Now we're gonna add a week I on a weak acid, and it's albumin. Now again, I'm simplifying cause the other week acid is phosphate. Unless you have renal failure. That's relatively rare, relatively rare. But albumin is very common, having a low albumin because if you're sick, albumin is what we call a negative acute phase protein. So when you're sick, you dropped your abdomen. If your albumin is normal, you're not sick. All right, so let's look at our soup again. There's your positive charges. Well, your age Plus, there's You're negative. Carrot is we've got the all important stronger and difference, which is the size of the attic. And it defined how big the attic is. Now, we're going to start filling the attic, so I'm going to start putting. I'm being the father, uh, of the household, you know, paternalistic. I get to put my stuff in first, and I'm gonna put my stuff in it. It's, um albumin. Check now what we're gonna put in, I'm gonna put in my books. So I'm feeling that space it So that space is now pushing the h o. And they're still doing more awake in it. Plus, So the balance that was way over. Now it's slightly less tilted towards edge. Plus, because I'm using some of that strong I different some of the attic space for my stuff. All right. So, as you start adding things to this strong this space, this attic space we call strong a difference you're going to see you're putting more and more. Oh, it out. So let's now at the 02. If you're positive, call. It was you're negative column again. There's yours. Theatric space or strong. I difference. We've already filled it with some of my books. That's albumin. Now my wife comes along says No, no, no. I'm gonna put my paintings in there. Okay, So her paintings going there. So let's look at 02. We'll go to has a dissociated coefficient. All comes from plants do, and some of it is dissociated to explode and bicarbonate. And that goes both ways. Right? So the bicarbonate, which is the part of the two, is gonna be feeling that space. So that's my wife's painting. So we've got my books. We have. We define how big the attic is. I put my books in there, my West putting her paintings in there, and we're pushing even more weight. Okay, so now we're having less a week. But there's still more awake. There is a plus to the balance with his way over towards a week is now just ever so slightly towards the weight. Plus. And don't forget your ph is 7.4. That is all kinetic. So are reference point. We say someone's acidotic rested Emmick. If they have a c h 7.1, there's still relatively Alkalaj. But compared to our reference 0.7 point four, we could say they're slightly acidy make or acidy MC. Okay, so we're still we're still on the outcome. Excited. We're still more awake than a plus, but we have less than we started cause we're pushing that awake out because the attic is being filled up with other things. No, that's it. What's that for? Like two. Guess it. There's your strong lions. There's your negative charges. There's your space, your attic space. I've got my books. That's albumin. My wife's got her paintings. It's my car. And now we're gonna add the lactic acid in just a strong eye on that's gonna push even more awake. And so it's gonna happen now is the weight is going to become even less than you're gonna be less space for a way. Now what happens in in practice unless you're on a ventilator because you are getting metabolically acidotic the adjusted. The variable you could just rapidly is your bicarbonate. You breathe faster. You reduce your coatue by reducing your oh, to you're dragging the black carbon equation from the right to the left, and you're reducing your bicarbonate so there's making some more space for a week. Okay, it's an adjustable. Variably snakes, um, through which is, don't forget, it's a sort of Serevent for school, too. So now your your your balance is still slight ever so slightly towards a week place. It's less than it was beginning. So what we just talked about are three independent variables that will determine your acid base status, and there will determine that by influencing the dissociation of water. So the first one is the stronger and difference. That's a size your attic, and then you're going to fill it with various things. You're weak kinds. It's the century album, and those are my books. So two is my wife's that becomes bicarbonate. That's my wife's paintings and anything else. And this is something it's often very hard to truly grasp unless you can let go of the old way of thinking is everything else are dependent on those independent variables to your PhD, it plus bicarbonate or all the consequences of those three independent variables. They're not the cause of the consequence there, depending as opposed to in depends according to Stewart. So if you want to calculate Stewart's method and you go to any textbook, this is what you'll see. You have to answer the following polynomial equations. You could do this with a computer. There are sites that will do this for you, and you have to come up with the answer to this. But most people that I know when they look at this, their eyes glaze over, and they just, uh, So what we're gonna try and do is use a slightly simplified way of arriving at the same thing. It's practical, clinically. So this is a way of trying to simplify Stewart's approach. So we're gonna look at four variables. These are four vitals. You can get it. Any acid base problem? You looking at blood guests? So first you wanted to look at is your base deficit. No, forget that's the sort of average that has all the various variables. Whether there alkalinity or acidic, that's the average number. We said a foot in hot water or foot cold. We're gonna look at this. We call the sodium chloride effect that strong. I difference. So therefore, you have to know what the sodium and chloride are, and most people that look at the base problems don't even look at those. Then you would look at the albumin effect because albumin is a weekly disassociated I on, unlike sodium in quarters, totally associates only about a quarter of it associates. So if you have a normal value, it's a 42. But see, that's the lab variables. Normal is 42 your albumin sake 22. That means 20 to 42 minus 22 is 20 when you take a quarter of that, and that will be what we call the album effect. Then you have lactic acid. Now, when you have a local, we have lactic acid. We need a lactic acid. It's a very, very important molecule. It's not a toxin. It's a vital molecule. We done without, like, gassy. But you do you have about one. So if you had, say five, be one minus five, that would be four minus four. A positive number, by the way, means you haven't alkalinity effect, and negative number is an acidic effect, then you want to look at the unmeasured diet. So is there anything that we haven't made her? So someone taking an aspirin overdose? They have a medical acidosis where someone's taken ethylene glycol poisoning and they ventured produce formic acid. I don't measure that normally, so that will come up as an unmeasured iron. And what you do is you add all the various variables and what's left over is what's in nature. Okay, you may have to take a while to look at this. Think of about this, and I don't expect you to come. I think you know, I understood acid base now. Of course not. It takes a while to think about this, but that's important cause once you get this under your belt, you'll have this with you for the rest of her fictional career. And this will quantify the medic bulk metabolic effects of Stewart's independent variables. So let's look at a couple of clinical examples relatively quickly, so this is the very first case we talked about. If you remember, it's, um, there's a pa trees, and it was a relatively mild we said metabolic acidosis. So the standard based deficit was four. So that's not too bad. So damn crying. Effect was seven plus seven. That means it's an alcoholic effect, cause it's a positive. So it was one. It was 1 33 minus 86 which was minus 40 So the difference was seven. So you've got yourself a large strong difference as opposed to normal. There was an albumin effect because you had so little albumin, your associate quarter of it. You had anatomy effected 8.5. Don't forget our oven's and assets. We have less acid. You're gonna have a more alkaline it effect. Your lot of gas in this case was 19, was minus 18, was one minus 19 minus 80 and whatever it was leftover that was unmeasured I It's at the mall. Together you have minus 1.5, so if you draw this out, you have an alcoholic effect, cause you have a large, stronger and difference a lot of space in your attic. You have less of that. Space is taken up without women because you have a low albumin. So it's another alcoholic effects that there's less face taken up. There's more space for a wage, but sadly, for us that space is now being taken up a lot by lactic acid. You have something that's unmeasured. I don't know what that was, and so your base deficits four. But that gives you a visual idea. What the heck's going on here. You can see there's quite a large disturbance, even though the base deficit of your eyeball that quickly it's a, uh it's not. So here's somebody who had a fair amount of saline during operation. You're looking at their blood. Guess two hours post operatively. So there's your PA from you. See you, too. I won't go through every one of these because I don't take you to walk. But if you were to do the arithmetic, you can do that at home, decided. Look at this again. I suggest stress you. Do you now have. We'll take a guess. You've been given saline. There's no story and difference in saline getting a lot of saying mine, so you're gonna have a strong I am difference that small. So there's going to be less space for you to fill your attic. Your attic is small. Now there's less space for other things, including a wage, so that's going to have quite a strong, acidic effect. It's negative. You've got a little bit of analgesic effect because there's less albumin than more. That's an alcoholic effect. You've got a slight degree of a lactic acid that's taking up some of that space in that attic. You have no one measured, I in effect. And your base steps is 8.5. So if you hadn't had that albumin being low, your base deficit would have been even worse. Who suffered? This is a made up case, okay? Because this illustrates that this is a peak at 7.4, everything looks fine. If you looked at it quickly, they step. Is it? 7.4 is a period. No problem, right? I won't go reading all the arithmetic here. You can do that at home, but you draw the south graphically. You can see. Yeah, this is made up. Okay. You have acidic effect. An alcoholic effect, an acidic effect, slightest cynic effect. And based on zero. So everything balances out, but your eye balling it quickly, you'd say, Oh, there's no problem. In fact, there is a problem. So let's go back to the very, very first case we talked about. We started this talk. So this was a 62 year old woman. True story this went came to the X emergency department had discharging to start from turkey recenter with a diagnosis severe inflammatory bowel disease with a massively discouraging fistula. Her blood gas showed this and we were called downstairs where I was called downstairs for the X emergency. Doctors were a little bit freaked out by what they saw that couldn't grab normal When you have a fistula, what we used to do is we used to measure what was in the fistula fluid. But here we haven't got time or just arrived. He's unwell. And we have to guess what's wrong with this lady? The pH is 7.9, so that's pretty disturbed. So what we see with this lady first thing, what do you notice about this case? Anything. I don't want to guess what you've noticed about her. She's got a very small, strong on. Got great stolen. She's very acidotic, of course. So he's got a really just to imprints. It's great they didn't name, didn't have the reflex. They they didn't have the reflex to look at. Sorry, Doctor. I don't know if you can hear me. Yeah, we just lost you quite a bit there. Can you talk about from the iron Gap? It? Yeah. So what I said was that the a any doctor looked at the pH. It was very abnormal. They looked at the lactate, which was normal. They looked at the 02. So it's not respected problem. And they just didn't even look. They don't have a reflex of Stewart's model to look at the sodium and chloride, so they just didn't know what it was to think. And they panicked. He called me. And right away, I looked at this and calculate the stronger difference using Stewart. So again, if it was something straightforward, I just traditional approach. No problem. Easy peasy. Quickly done. But because this was more complex, I then started using Stewart's and use the principles of Stewart's. And there I saw a stronger agents of 18. So too quickly solve this problem. I gave her bicarbonate of sodium, sodium bicarb, and you can see now this is over a few minutes, but they're strong. A difference is becoming 22 over a couple of minutes. now a peak is getting better. So this was just a logical way of approaching this. What seemed to be a complex and undiagnosed acid baseball least the A Any doctors were totally complex fighters. So that's what we're Stewart's really helped me a list. So a couple of quick fire points did you know, can you name three organs based on what we just talked about? What we talked about three independent variables that control acid base balance in your body and quantitative imports. In order of quantitative imports. You give me an idea what three organs are? Um, Abdullah says, uh, kidney and lungs with a lot of kidney and lungs. Okay, I said in order of quantitative importance, who would be lungs first? Good lungs. Because you have a lot of salt to your blowing up. Okay, so you want to see if the planet stop breathing number two? Well, you said kidneys. That's good. Number three. Could it be the gastrointestinal system? Uh, can you be more specific? Stomach? No. What was the third? What was the third one of the with the independent variables again? Remember them sodium chloride? That's kidneys controlling that. So to What was the other one? Yeah, What produces Element? Liver, Liver. So the liver is an acid base organ. People forget that. Okay, that's important. So here's some interesting facts. We just said this. Control the acid base, the lungs. 17,000 milliquivalents per day. The kidneys. About 60 mil equivalents for Dave chlorides lost an albumin by the litter. So the three acid base controlling organs the kidney maintains your extra set of foods strong. I difference by excreting chloride. Some people said you could actually determine someone's acid base status like looking at there, their urinary filtrate. I think that's a little bit putting it far. But what's interesting? You heard of something called renal tubular acidosis? Yeah. Okay. So you cannot excrete chloride without a positive ana. And the positive I only used is normally ammonium and a four plus, if you're tubules are damaged and they cannot produce an egg four plus, you cannot get rid of chloride. So you can't maintain your strong I indifference and your exercise or fluid. So it gets smaller because you're retaining. You're retaining chloride, and so you get an acidosis. That's due to the impossibility of your renal tubule to do, produce ammonium and then see a company chloride. You can't get rid of glory adequately, so you get a realtor of your acidosis. Diarrhetics, as we said, is a really good way of giving somebody and alkalosis you put someone on diarrex you very, very often almost always see in Alkalosis because you're losing more chlorine, you would. Normally you're losing more klor than sodium, hence your stool and difference in your exercise or food center. In plasma, it gets bigger. Hence more space in your attic for a wafer. Do you increase your story and difference and you could get alcoholic. So two is used. As we said for Rapid addressed, it's wide suddenly, add, let's say, for argument's sake, I add, um, ketoacidosis from a diabetic. My space in my strong My attic, if you like, is going to be upped. A pied by the the strong irons of ketoacidosis acids from your diabetic ketoacidosis and my my body will react by quickly blowing off so two and therefore shifting the the equation of bicarbonate towards the left and hence reducing the bicarbonate. And that's in my space in my attic, if you like. Okay, that makes some space for for, uh, for the weight. And chloride is a longer term, a gesture that takes about 24 48 72 hours. So it was rapid chloride adjustments is longer. So to recap, everything been through a lot here. So doesn't matter. As we said, it's the cause. Uh, because of the acid base disturbance that usually is the real problem, not the acid based servants per se. We have some definitions. Simple definitions. What is a peek? Just just a simple way of quantifying a pluses you could use, um, animals. We did, in fact, acids just more active person, which mine's basis more weight from minus native plus a really simple definitions. Strong electorate. Don't forget the spaghetti water. Okay, no sodium chloride and week electrolytes believe parsley, part with associates. We had the famous my old friend Davenport diagram, which I still use. I like that we had the definite kind of would've based deficit is don't forget it's within normal. So two. So it's a cure the metabolic, uh, measure. And it's an average you can have opposing. And you saw opposing influences both acidic and l colonizing. So you're getting is an average with the base deficit we talked about Stewart's was a chemical of approach. And how you have to understand, understand the physical chemistry of water, strong lions we kind of go to We're using deductive reasoning. We built up this soup with the strong and haven't seen the size of the attic, and we're gonna fill the attic with various components, and the clothes component is gonna put away from minus out of the out of or increased. So you have more space for weight from minus. That's gonna alter the balance of age plus two, which minus. And as we said to repeat again, your three independent variables, according to Stewart, which means your acid based that. And since you're stronger and difference that sort of sodium chloride week, I on some centuries albumin and so two PCO to everything else are dependent variables. And lastly, this is just a a sort of easy or quick and dirty way of of issue allies. Those complex those complex problems. If you have something it simple, just use a simple techniques based epicenter. Davenport Diagram. Diagram. When you get something that's complicated, don't hesitate to use this draw it out and you can get a really good field. What's going on? That's thanks a student. That is all I have to say about that. So be happy to take any questions for you from you. Brilliant. Thank you, Doctor. If you go any questions, guys, put me in the chat or feel free to, um, Utah And ask the doctor, Doctor, would you say that in terms of treating acid base, uh, problems on the day to day like, ah day today Cases. Do you think it is it normally work, given the acid or the base? Or is it better to remove the cause and just wait instead? Oh, of course, there's no doubt about it unless you've got something. I mean, I'm trying to think of many cases where correcting the acid base problem without correcting the cost will improve mortality. I can't think of many. It's it's, um, it's really again. I can't emphasize enough. Let me tell you something that's I find interesting there, so trying to be a total iconoclast. But there's so many things that you told him textbooks that just don't make sense. So, for example, they'll tell you that if you have an acidosis, It depress. Is your cardiac contractility You go heard that, right? Yeah, Well, if you read about where that comes from, it's in animals where they take the heart out of the body and put it into a bath. Electrolyte bath. And yes, it will depress the cardiac contractility. But your heart is not in a bath. It's not outside your body. So one of the things that acid base will do is a disturbance. As a Donna Chris disturbance, it'll cause an increase in sympathetic activity. So that tends to counter act that. So things are much more complicated. So again, I'm not saying leave in acidosis. My biggest problem in acidosis is why have I got this acidosis? So one of the classic things I said earlier, someone's got electric acidosis. We'll just put him on dialysis and die out dialyze off the lactic acid. First of all, you only dialyze about three or 4% of your lactic acid off most of us absorbed by the liver, kidneys and muscles. So that's nonsense. But that makes no difference whatsoever to Elka. When you dialyzed someone's lactic acid or what you want to know is why they got this. Like to guess it. And what can I do to stop this lactic acid from being produced? That's the key to treat. Thank you. Bring in. Um, but this is asking in the case where you gave for is a mind to the asthmatic patient If the other doctor hadn't given sodium bicarbonate. Yeah. How would you fix the initial P. H? Well, you know the reason I gave you that story. I hope I don't get missing. Understood? Please do not tell people. I said the treatment for asthma is frozen night, and I can think of lots of reasons where that be kind of difficult because you get you dry. Somebody out there already got dry secretions, and they get these what you call these sort of totally plugs in the bronches bronchioles What I was trying to illustrate there was how, on understanding of the acid base mechanisms if it was Ms understood, which was the case with the bicarbonate. Things were made a lot worse. And, um, you know, you can imagine this guy I can't get rid of this. Oh, to the stone has made it go to worse because they gave Morsi go to. That was the last thing I want to do. I was just trying to really illustrate what another approach would be. But But I'm definitely not saying. I mean, these are difficult cases. I'm not saying for a second the treatment of aspirin it's cruising on. I'm just trying to use it as an illustration of what you know of another standing of acid base. Problem would be No, no, I know. So how would you fix the initial piece if you got that piece of their battle off? 6.35. How to fix that? Um, you know, I'll tell you, I'll tell you what I would've done. You remember the very, very first slides I showed you on volunteers, And this something I actually had myself. I was doing my own volunteers, but we all had the same the same numbers we had. Ph is, like 6.66 point seven purely from a respiratory acidosis point of view. This man's problem isn't his acid base problem. This problem is, he can't get rid of so to. So we've got a weight or some. How many gives something else that would make his, uh, dilate taking his bronco I more effective. That was the problem going to solve. I don't think I don't even bother myself. I just left it. But you know, I may be wrong about that. Look at those studies again. Those are healthy volunteers. I agree, but they have very, very low. PH is as long as they're oxygenation was okay. And again, if you have some of the asthma, what kills you with asthma is because you can suck air in, but you can't blow it out. You're like a balloon getting bigger and bigger and bigger and bigger. Either it pops and you get attention to methorexate Or because the balloon gets so big, it crushes the very fine pulmonary capillaries. And you're again. We'll go on to another subject, right? Heart. You got two hearts. You're right and left. Or your right heart is an aerobic dancer. Very thin walled muscle. Your left heart is about six times a muscle mass of your left or I'm sorry. You're right. Heart. So your left heart's a big you know. It's a muscle or a weight lifter. Your left heart can pick up really big weights and and handle them. So your BP could go from 1 22 200? No problem. Your right heart, on the other hand, can't. It's like a name or big dancer cannot lift those heavy weights. So if you crush the capillaries with those distant ended alveola, the right heart suddenly is given this massive load to get blood through. It's got this massive resistance, and it can't get it through. It fails. That's why you divestment. Usually it's because you have right heart failure. Anyway. That's really not the subject to tonight's straight, Um, how can we know if, um, acidosis is metabolic or respiratory in nature? That's easy. You look at this ear, too, and if you you have a mixed with sleeping, you have the steel to that's high higher than normal, and you have, ah, you know, based deficit, for example. That's normally high. Then you got yourself a mixed the Balkan respiratory. You look at you. Look at all those different actors. That's that's really, um, how does altitude, um, change? Um, partial pressure of calmed outside on the pH. It's a very relevant question to us because we're out after two right now. Yes. So what happens when you go to altitude? You immediately adjust by because you have a lower you have your percentage reduction is the same, but your barometric pressure is lower. So 20% 21% off your barometric pressure of your barometric pressures. Half you're going to have half. So on Mount Everest, for example, if you get the same damage of pressure 21% of your breathing air. But the bar Sorry, The barometric pressure is so much lower. It's the equivalent of your breathing 7% of oxygen. So you're going to get, uh, you're gonna really drive your spiritually center, and you're going to start hyperventilating and your hyperventilation is going to cause you I think we talked about this in a very, very first talk with oxygen Liver E. It's going to shift your oxygen association curved to the left. So for the same p 02, you could have a higher saturated um, but that's why you do that. In fact, interestingly enough, you know what drug we use in people that have to acclimatize quickly. Anybody, no idea. And there's nothing in the Charlie said is all might Diamox And the reason behind that is is that when you go to altitude initially and you haven't had time to adjust, you have not a week to acclimatize. You start hyperventilating as you hyperventilate. You blow off so to you become more Alkalaj. They often very alcohol on it. Because your Alkalaj, you're going to reduce your respiratory drive. And so therefore, you're going to start increasing your your hypoxia. If you like, you're gonna get more hypoxic. So what Diamox does? It's a carbonic anhydrase inhibitor. It gives you a medal acidosis so tired, like the counter counter balance the respiratory alkalosis to keep you breathing fast. And that's just, you know of Thank you. Um, because that drug would would cause could be a cause of a metabolic. Acidosis is well concerned. If you that's the point. You try a let's look counterbalancing metabolic acidosis to counterbalance the Risperdal closest to keep you breathing. And Hugh was asking about the final case that you had the hypothetical one. Hey, asks So in, Doctor in the made up case, he said at the end that we still have a problem. How would you fix it? Because overall everything seems to balance out. Oh, I see. Yeah, well, uh, you think back with that case was so you know, again, it was a hypothetical case. But, I mean, for example, if the straw my and difference, first of all, what I fix it, is it Is there a problem? I mean, yes, there's a pH, except normal fact. It wasn't was not a girl. So if there was a small strong I a difference because we gave to much saline. Well, I might give diuretics, so I make the stronger difference bigger. If there was not enough albumin, and so that cause an alcoholic effect, we'll get more albumin. So I try and adjust those variables to come back to normal. That's really everything. There's one last question we're going to you guys. It's the opposite. The altitude one. It's if the patient is a diver. Uh huh. Passing it. Okay, you're you're more accustomed to being high up in the Ousman. You ever see Okay, thank you very much for that. Interesting, um, lecture doctor Google. It was really helpful for helping to explain acid base balance in terms of irons, which was something that we probably found quite difficult before, so thank you very much. Um, yeah. Okay. Well, thank you for attending. And, uh, have a good weekend. You too. Thank you.