Good evening everybody and welcome to another fantastic webinar tonight with Martha Cannon. We are very proud to bring this webinar to you by the sponsorship of Breathe Easy. So a huge big thank you to Breathe Easy for their sponsorship of the webinar tonight.

Just a little bit of housekeeping for those that haven't been on with us before. If you have got a question for Martha, just move your mouse over your screen and the, the little control bar will pop up. There's a Q&A box.

Click on that, type your questions in there. They will come through to me and I will hold them over to the end. And then if we've got enough time, we will go through them.

If we run out of time, don't worry. We will download those questions and we will get those answers to you. So we're all in for a treat.

I feel like a bit of a fraud introducing her because we all already know her, but Martha Cannon is a specialist in feline medicine and the co-director of the Oxford Cat Clinic. A first opinion and referral cat-only veterinary clinic in Oxford. Martha combines her active involvement in feline referral medicine with a commitment to providing feline-focused continuing education for veterinary surgeons and veterinary nurses.

Her lectures focus on providing an up to-date information set and practical approaches to diseases that are commonly encountered in day to day veterinary practise. She's also proud to be involved in the developing and promoting of the ISFM cat-friendly clinic programme, which provides constructive advice on how to reduce the stress cats suffer when visiting veterinary practises, making veterinary visits easier for the cats, the owners, as well as the veterinary staff who work on them. Martha, a warm welcome back to the webinar vet and it's over to you.

Thank you very much indeed and welcome everybody to this this presentation. Which again, as as Bruce has mentioned, is kindly sponsored by Breathe Easy. So we're gonna look at the whole subject of, feline asthma, as it's often called.

I must admit I tend to refer to it more as chronic bronchial disease, CBD, chronic bronchial disease, will come on to the difference and what the different terminologies mean. But what I want to focus on is the, the approach to how we recognise this condition. Some of the complications that can arise from it, to, to highlight really the importance of, of appropriate, long-term therapy for this common condition.

And then, of course, we'll look at practical ways to achieve that. The picture on this front slide illustrates, the, the Aeroca, inhaler and, and, face mask and spacer bar, which of course is a, a Breathe Easy product. We will talk about the uses, the advantages, the disadvantages, and the, you know, the, the, the limitations and so on of that treatment therapy.

And, and then, as, as Bruce outlined, if there's time where I'm certainly very happy to take any, any questions. But let's look at a typical case, that might present to you. You will all, I'm sure, have seen many cats like Alfie here, who is a 10 year old female neutered domestic short hair, with really quite a long history of bouts of coughing.

So when she does have a cough, she has quite a little, episode of coughing. It was relatively, an infrequent occurrence, but in recent years, it's happening much more often until or unless she gets treated and her referring vets have been treating her with intermittent injections of Depomedrone, which they found resolved the cough very effectively. So this is, this is Alfie in our home environment, you'll have to listen quite carefully because the sound is quite faint, but if I start the video, I hope you'll be able to hear.

So this is a very typical appearance of a cat coughing. And as I pause it there, you can see that, straightened out, flattened profile, neck extended, head down, keeping the airway, and making the airway a single line and keeping it open. And as she coughs, it's that soft, quite dry cough, often quite musical, almost, coughing noise.

But if you watch the cat as they Of. Ultimately, there is usually an exaggerated swallow movement, because they are actually bringing up some, some mucus, some phlegm from the, the, the airways, from the trachea, which they don't spit out. So it's not a productive cough in the traditional sense.

But as you watch the cat, you will see that there is, something coming up into the mouth. I'm just gonna run it on a little bit. And there's a swallow.

And another one. So, quite a dry sounding cough, but with some productive mucus. Now, Alfie had been coughing for a long time, and the, the, the condition had been relatively well under control with the Depomedrone until about 6 weeks prior to referral, when unfortunately, she'd taken quite an acute turn for the worse, with a very severe episode of coughing and dyspnea.

And subsequently, since then, not been, not been quite right in herself, coughing more, and of concern to owner and vet was that this severe episode had happened just 3 weeks after a Depomedrone injection, when normally they would have expected to get much longer control. And so quite a typical history. And cough is very much the, the, the, the watchword for these cats with, with chronic bronchitis and, and asthma.

They can, of course, have wheezing. They can have these acute episodes of dyspnea, but there will always be a history of coughing in these, in these cases. Physical examination is often not terribly rewarding, and that was certainly the case with Alfie.

A slightly overweight cat, so good body condition, good coat condition, quite a, you know, quite a shiny, healthy coat. No heart dysrhythmia, no murmurs, no gallops, nothing to suggest any cardiovascular abnormalities. And in the consulting room, mild tip near, the rapid res respirations, but not really a dis near, so no real increase in effort identifiable.

And again, that would be quite typical. When you're examining these cats, obviously, you want to have a listen to the chest, and you will often hear a mild increase in the kind of dry, breathy airway sounds. You may hear some wheezing, and if you do, that will tend to be on expiration, so on the outward, portion of the, the breathing cycle.

But when you are listening to a cat with a cough, the other thing I think that's always worth doing is just to have a gentle pinch, a gentle palpate of the trachea. And also actually to put your stethoscope over the trachea and listen to the sounds that are referred from the airway. And you will often hear a lot of rasping and gurgling in that trachea in a coughing cat.

And when you gently pinch the trachea, you should have to pinch actually relatively firmly to elicit just a single short barking cough in a cat. That would be normal. In cats with, either an upper respiratory infection, a herpes calichi type infection causing a sore throat, you might get a very exaggerated swallow, but not really a cough.

So if you get a real bout of coughing in response to that, that generally isn't an indication of airway irritation, airway inflammation, and we'll clue you into the fact that, that again, perhaps we're looking at a, an asthma, chronic bronchitis-y type situation. So, coughing is a relatively common sign in cats. Anytime you have coughing in any animal, it indicates that there is either inflammation or narrowing of the airways and obviously inflammation.

Causes narrowing of the airways because of the increased mucus, on the, on the, on the mucosa that, that, that narrows the airway. Of course, in some species you will commonly get a cough if something external is pressing on the airway and narrowing it, but that would be much less common in cats. So generally when cats are coughing, it's because of problems within the airway.

And if we think of the common causes, from the, from, if you like, the mundane to the, to the more serious, probably the most common causes of coughing that we see is either worm migration, causing a transient soft cough, especially in kittens and young cats if they haven't had a good worm. Worming profile, you know, the owners haven't been worming them regularly, so we shouldn't overlook that. And certainly it would be unusual to get chronic bronchial disease in a young cat, and so we shouldn't get, you know, we don't want to be putting them on lifelong therapy without ruling out the simple things.

And of course, oddly, fur balls will cause coughing. So cats, when they are trying to bring up a fur ball, will go through a genuine cough phase before they move into a wretch in order to bring the fur ball up out of the stomach or, or oesophagus. So a genuine cough from the airway as a precursor to a vomit of a fur ball.

If we think of the, if you like, more pathological causes, relatively long list here on this slide. At the top, I've put chronic bronchial disease and feline asthma in a darker colour, because they are far and away the most common causes of chronic cough in an adult cat, and we should always have that in mind. The conditions I've listed in a sort of paler pink colour are less common causes of cough, for one reason or another.

Lung worm, a strongullus abstrusis in the cat. A cat with lung worm may be completely asymptomatic. If they are showing any signs, then cough will certainly be prominent amongst the signs they show.

But depending where you live in the country, it's a relatively rare condition. And so, not, you know, I haven't put it into dark, in the dark colour to say that it's a very common cause of coughing, but if a cat has lung worm, it will commonly cough. And that's a bit of a contrast to pulmonary edoema and bronchial pneumonia, which are quite common, but which often do not cause cough in the cat.

So congestive heart failure, causing pulmonary edoema, rarely causes a cough in a cat. It can do. It's on the list.

We need to be aware of it, but it's not as common for cats with heart failure to cough as it is certainly for dogs. Bronchial pneumonia, we do see, very often they will be dysneic, very often tachyneic, sometimes fever. Cough may be a more minor clinical sign, but certainly one that we should be aware of and certainly a sign that we should take seriously if an owner reports coughing.

And then unfortunately, we of course do sometimes see neoplasia in cats in the lungs and the airways. But again, relatively uncommonly will that cause a cough. So again, that's in the, the less common causes of cough, but clearly something that we need.

To be on the lookout for, and I would certainly advocate a level of investigation into the cause of a chronic cough, in any case that you can encourage the owners to let you do that, because again, although asthma, chronic bronchial disease will be the most common, these other conditions are there. They need to be recognised and of course they need to be treated in a a rather different manner. So, if we do think about those top two, if we think about chronic bronchial disease, feline asthma, again, the most common cause of chronic cough in a cat, and in affected cats, they may also suffer episodes of acute dyspnea.

And I'll show you a video shortly of that and we'll talk about how to recognise what the cause of the acute dyspnea is. And again, the chronic bronchial disease, lower airway disease will be associated with expiratory effort and exspiratory wheezes, expiratory noise when you listen with your stethoscope. So again, I'd really encourage you when you're doing your physical exam of, of cats to try and get used to, watching the breathing pattern, and trying to get used to associating any noise, any effort, any sounds you're hearing with the phase of respiration, because it can be very helpful in identifying where the noise is coming from.

And of course, one of the hallmarks of chronic bronchial disease and asthma in cats, and one of the things that often helps to confirm that we're on the right track with the diagnosis is that it does tend to be very responsive to treatment with corticosteroids, and often really quite a low dose of corticosteroid will be effective. So we're, we're generally talking about anti-inflammatory doses of corticosteroid, rather than needing to go to high doses and Immunosuppressive doses as we sometimes need in some of the other chronic inflammatory conditions of cats. We know that this is a disease that is most common in young to middle-aged cats.

Adult grown cats, so again, quite unusual, it would be unusual to see it in kittens, but generally young to middle aged cats, so in the sort of 2 to 6, that kind of bracket, when they start showing signs, and very often it will become less severe as time goes on as, as they get older, as indeed, some, some cases of asthma in humans are, are similar. It is more common in Siamese and oriental cats. They do seem quite prone to it, but it's a common condition and we see it in, in all breeds and in and in no breeds.

So we see it very commonly in domestic short and long hair cats as well as Siamese and Orientals. So I keep referring to this as chronic bronchial disease or asthma. And the two conditions are very, very similar.

And in fact, in the veterinary world, we can't easily differentiate between them. But asthma, by definition, is a genuine allergic reaction to some inhaled allergen, usually a, a pollen or a house dust mite type, type allergen. And being an allergic condition, very often there will be a predominantly eosinophilic inflammation if we do do a bronchialveolar lavage and look at the, the fluid.

So asthma is a genuine allergic condition and in humans, the definition of asthma is a condition of of reduced expiratory function that responds to treatment for allergy. So the, the, the, the, the definition incorporates the, the fact that it is a, a, a true allergic reaction. Whereas chronic bronchial disease, which certainly in my experience, probably more common in cats, is a a non-allergic and non-infectious cause of chronic airway inflammation.

So these cats often have a predominantly neutrophilic inflammation. But we don't see a primary bacterial cause. And so we need to be quite careful when we interpret bronchoalveolar lavage to make sure that we are not using the presence of neutrophils specifically to, to suggest to us a new and rely on antibiotics to, to treat it.

I'll, I'll come back to that, a little later when we talk about diagnostics. But really at this stage, just to say that the, the technically, the difference between chronic bronchial disease and asthma is whether it's allergic or not. But in reality, The clinical signs are the same, and the approach to management is much the same, whether we have asthma or chronic bronchial disease.

So yes, we need to rule out those other causes, edoema, bacterial infection, and so on. But beyond that, the distinction between asthma and chronic bronchial disease, we perhaps in the clinical setting, don't need to worry about too much. So again, clinical signs for both conditions, chronic bronchial disease or asthma, this chronic intermittent cough is absolutely the hallmark.

They can suffer with lethargy and exercise intolerance, if indeed you can identify exercise intolerance in a cat. Very often there will be at times, at least an expiratory wheeze, which you will hear with your stethoscope, but at times it may be audible to the owner. And some of them will have tachypnea and episodes of acute dyspnea brought on by, for example, an increased exposure to allergen if it is an asthma.

And those cats can be in quite an, an acute dysic state and need some some quite urgent attention just as a person suffering an asthma attack. And again, classic, expiratory effort in these cats. And if you are watching them coughing that classic position.

Neck out, elbows out, widening the chest, straightening the airway, and then with the cough, often an exaggerated swallow movement after a bout of coughing in order to swallow the mucus that has been brought up into the mouth. So, before we go on further into the, into the diagnostics, just a little bit more to say on the, on the clinical presentation and, and how to recognise, or how to identify the causes of severe dyspnea. So I just wanted to take a few moments.

To think about that emergency presentation when the cat comes in acutely dysny, and it, and it, it's a, you know, it's a stressful situation for us, it's a stressful situation for the cat, and we want to make some good treatment decisions as quickly as we can. And without resorting to too much in the way of diagnostic work, because the very act of handling the cat and restraining the cat in order to take X-rays or to do an ultrasound or to do any diagnostics can actually make the situation much worse. So I make no apology for breaking out of what has up to now been a, a discussion of chronic cough, to just talk very briefly about looking at cats when they present to you with acute dyspnea.

And trying to recognise the respiratory pattern. So we have 3 respiratory patterns that we think about as commonly presenting in cats. And this first one is a cat with this cat on the, on the screen here has a pleural effusion.

And so the, the, the problem for this cat is drawing air into the lungs. So the effort full phase of respiration is the inspiratory phase. And the inspiratory phase is when the chest goes up, the rib cage goes up.

And so, I hope you can see there that it's effortful to pull upwards. And then the chest falls down quite easily and naturally, and then the cat has to heave to pull the air in because of the lack of elasticity because of the fluid. So inspiratory effort is plural space disease.

It's pleural effusion, it's pneumothorax, and you'll see that classic increased inspiratory effort, increased upward phase of respiration. So I hope you can see that there. Then the second respiratory pattern that we think of is what is called a restrictive pattern.

This is where there is fluid or debris within the alveolar space, restricting oxygen, movement, restricting air movement and restricting oxygen transfer. So this would be, typical of a cat with pulmonary edoema or, interstitial pneumonia, usually a bacterial or mycoplasma. Pneumonia.

These cats will have a rapid, shallow, but symmetric respiratory pattern. So the inspiratory and exspiratory phases are similar. It's quite, it's shallow.

We don't, don't have that big increase in effort to breathe, but just a rapid, shallow, symmetrical movement, which I hope, again, you can see in this cat if you just look at the, the, the, the sort of, profile of the chest there. So you can see that the up and the down phase are similar. And this, this particular cat is a cat with pulmonary edoema.

And then the third pattern, and this is the one that's relevant to our discussion today. This is the way a cat will present if it is in acute dyspnea, because of lower airway disease. So in loose terms of asthma attack, these cats will have an increased expiratory effort.

It's quite difficult. To video, it's quite subtle to show. So again, it needs a bit of practise looking at these cats, but this cat is showing an increase in effort in the downward phase when you watch it's, it's rib cage, it's the downward phase, which is slow.

And if you watch the abdomen, you can see it's actually using its abdominal muscles to help to push the diaphragm forward and push air out because it's breathing out, which is effortful for this cancer. So this is like a horse with a, a, a, a, a, a COPD as a kind of abdominal heave going on. In order to try and force air out of the narrowed airways.

So again, I hope you can see there that it's the downward phase of the ribs, the outward phase that is effortful for this cat. It can breathe in quite freely and it has to push to force the air out. And if you see that, you can be pretty confident that you're dealing with low.

Airway disease and perhaps the cat needs emergency steroid rather than needing, for example, zamide if you have a pulmonary edoema. If you speak to the owner, these cats will have a history of cough. And if you can listen to their chest without stressing them too much, you will usually hear expiratory wheeze.

OK. But if we go back now, so sorry, that was a little bit of a diversion, if we go back now to our classic chronic coughing cat, and here again is another example of a coughing cat. This one is a bit more mobile.

But again, it's quite a dry cough by the sound of it. But at times, there is an exaggerated swallow because of the mucus that's coming up into the, there it goes again, it goes, the, the, the mucus that's being brought up into the mouth. Other than that, the changes may be very subtle.

Again, that increased tracheal cough reflex is quite a useful indicator and increased expiratory noise when you listen with your stethoscope over the trachea, which I would encourage you to add to your physical examination of of cats with respiratory issues. If you don't already do it, you can pick up quite a lot of information by listening there. OK, so having established that we believe there to be a lower airway problem, it may be tempting with a cat with chronic cough to move straight to treating it for chronic bronchial disease or asthma, but I think those other differential diagnoses occur.

Commonly enough to justify us trying to investigate things a little further to make sure that we are treating the condition that we believe that we are treating. And of course, chest X-rays would be an early part of that investigation. But I would say here that in order to get good diagnostic quality chest X-rays in a cat, you nearly pretty much always are going to need at least some sedation.

And actually, ideally a full general anaesthetic with intubation, so that you can potentially get inflated chest films and make sure that the lungs are air filled, because it makes a huge difference to the quality of your films and the ability to pick up subtle changes. So the changes that you might see in a cat with chronic bronchial disease are quite variable. They may be very subtle, you may look at the X-rays and feel that they look quite normal.

But things that we want to look out for in particular are hyperinflation of the lungs. So again, because the problem for these cats is the expiratory phase is the breathing out. They tend to have well inflated lungs when you take your pictures.

So these are actually an example of a situation where you do not need to manually inflate the lungs to take the X-rays, because the condition itself causes hyperinflation. I'll show you a picture in a second, but what you're looking for is a flattening of the diaphragm. And in particular, a useful thing to look for on the lateral is to see whether you can see air filled lung behind the heart in that gap between the heart and the diaphragm.

So this is quite an extreme picture of of a cat with quite severe bronchial change in order to illustrate this. But here is what I mean by the flattening of the diaphragm. So this cat has not it's not got in.

This is not an inflated film. The cat has got an ET tube in. You can just see the tip of it there, but it's not an inflated film.

This is the cat, trying to breathe for itself. And you can see this flattened, diaphragm line. The tip of the lungs extend beyond the end of the the rib cage, and that's another indication of well inflated lungs and see that gap behind.

The heart, between the heart and the diaphragm. It's not a pneumothorax because we've got lung pattern in that area. So it's inflated lung, and that, if you have not inflated the lungs yourself and held the the bag, then that is a strong indicator of lower airway disease.

And what we also see on this picture, although I appreciate that it's hard to identify on a small screen, is the clash. Sick increased bronchial wall shadow, if you like. And so we've got little tram lines and little end on donuts as they're called, where we can see the bronchial wall more clearly than we than we should.

And in this case, it is extending quite far into the periphery, because it is quite an exaggerated change. So that would be the sort of typical signs that we look for in cats with asthma and chronic bronchial disease, the hyperinflation of the lungs, and the increased bronchial patterns, so the, the, the, the little doughnuts and tram lines. I'm gonna take you back to the way we started and and remind you about the cat Alfie, who had this long history of bouts of coughing that responded to steroid, but had suffered a recent, quite severe deterioration in, in the in the cough and the dyspnea, even though it was at a time.

When the corticosteroid was still active, and you would expect the inflammation was reasonably well controlled. And unfortunately, what had happened with Alfie is something which can happen in cats with poorly controlled chronic bronchial disease or asthma. And then then you see this typical picture on your X-rays.

You can see by the by this extreme hyperinflation. With flattening of the diaphragm and almost rounding off of the tips of the lungs because of the hyperinflation and this huge gap behind the heart. But what I want to draw your attention to is this.

Which on first glance, you might think was fluid, you might think maybe pleural effusion, but it's very localised, isn't it? It's, it's an odd place for fluid to settle. And when we look at the DV view, we can see that it's this right cranial quadrant and that this side of the chest is reduced in width compared to this side.

So you can see the lungs, the, the, the ribs here are at in a more acute angle. And there is a, there's less, there's less tissue holding out the lung, the, the, the, the ribs, if you like. And this is typical of a collapsed lung lobe.

It's nearly always the right middle lung lobe, as we see here. And unfortunately, this happens in cats with poorly controlled chronic bronchial disease, when mucus builds up in the airway and causes a plug in the bronchio, supplying that right middle lung lobe, that blocks air passage. The air that is trapped gets gradually reabsorbed.

There's no New air coming in because of the blockage and so you end up with this chronically and and permanently collapsed lung lobe. So this is quite common to see on X-rays, especially as I say, where there's been poorly controlled inflammation. And unfortunately, this is this is not repairable.

This will not reinflate, even if we do get The inflammation under control. So to my mind, this is quite a significant complication of this disease, and one of the reasons why we need to try to maintain good control of inflammation in these cats, not just intermittent control when the cough builds up and gets very bad. But really to try and educate and encourage owners to try and control the inflammation on a daily long-term basis so that we don't get this kind of chronic complication.

So I'm gonna add to the things that we are going to look out for in our X-rays of cats with chronic bronchial disease. Yes, we're going to look for the hyperinflation of the lungs, the peribronchial infiltrates that the so typical, but also this right middle lung lobe collapse. When you see that, it's pretty much athhenemonic for lower airway inflammation.

And another addition down here and the reason why we often do need to still investigate further, we can see patches of alveola pattern, patches of interstitial change because of a buildup of mucus and a and a and a propensity to secondary infection. That will then lead to those other changes. So it can be quite a complex pattern and it can be quite difficult to be certain from an X-ray alone, whether we are dealing with a bronchial pneumonia or whether we are truly dealing with, either a a sole chronic bronchial disease or more commonly a chronic bronchial disease with secondary bacterial or mycoplasma infection.

So if that is the case, if we're looking at an X-ray more like this one again, I know it's quite small, it's probably quite difficult to see, but we have got, we have got quite a marked peribronchial pattern, and it does extend right to the edges. We've got a big gap. Between the, the, the, the edge of the heart and the diaphragm, which is relatively flattened on this DV view.

But we have also got some areas of alveolar infiltrate, which I appreciate are hard to see, but there are some air bronchograms going on in places. So this cat certainly has signs of chronic bronchial disease, but is that the only thing that's going on? Is that the primary problem?

Or, given our previous list of differentials, should we be concerned that there might be bronchial pneumonia, there might be even neoplasia or some other condition. And so this is where if we can, it's, it's nice to then take the diagnostics a step further. And to consider doing bronchialveolar lavage, which is actually a very straightforward technique.

It's a very quick technique. If you have anaesthetized the cat to get good X-rays, it really only adds a few extra minutes to the time of the anaesthetic in order to get some really nice samples from deep down in the lungs. If you undertake it using an an appropriate technique, it is a very safe technique, although, of course, it needs to be approached with due care.

And I think it can add a lot of, of useful information. So I just wanted to run through with you how I do bronchoalveola lavage. You can get very technical.

You can, of course, use bronchoscopes and so on if you have them, but probably most of you will not have bronchoscopes small enough to go down a cat. And even if you do, per And, and, you know, we do in our practise, but I don't use it to get bronchoalveolar lavage, because I find I get much better samples using the technique I'm going to outline to you. If you have a bronchoscope and you get on well with it and you get good samples that way, absolutely fine, of course, to continue to do that.

But if you do not, and if the signs that you're seeing on your X-rays are quite diffused, so that really a lung washing from any part of these lung fields is likely to be representative. Then I think bronchialvea lavage is a very useful technique. So in order to to do this, what we need is a sterile ET tube of a suitable size to provide a good, a good airway for the cat, but also be wide enough that we can pass an open ended lava tube through the through the central core of the ET tube.

If you've got a red rubber feeding tube, nice and soft, that's lovely. Cut the end off, so it's an endo. Opening tube.

If you don't have red rubber feeding tubes, then here we can see this is just a, a dog urethral catheter. Again, you need to cut the end off so that you so that you're not using the side ports, but the fluid is coming out and being sucked back in through the end of the open end of the, the tube. And you do need to be careful because when you cut the ends, you know, you may leave some little sharp edges.

So, so be very careful in, in introducing. This, but with caution, it can work very well. And again, it must fit through your ET tube in order to allow you to use the ET tube, almost like a sheath to protect your, lavage tube, so that it doesn't contact saliva, the pharyngeal content, and so on.

And it keeps it nice and clean. Otherwise, you'll pick up a lot of contaminants from the, from the mouth. So then, we're also gonna need a wash fluid.

We just use, some warm sterile saline. So certainly room temperature and ideally body temperature, sterile saline. And what I like to do is to use about 5 mLs of fluid to wash into the cat, but put it in a oops, sorry, put it in a 10 mil syringe.

So that you, so that you have extra syringe capacity, and I'll, I'll show you why that is when we come to, to show you a video of how to do the actual lavage. And then collection tubes, we usually put it into EDTA for cytology and a plane tube for culture and PCRs. So then with the cat under anaesthetic, I like to give them a, a, a sort of pre-med, if you like, of, tebutylin.

So tebutylin is a bronchodilator. Give it IM at quite a low dose. It's quite safe.

It does have some cardiac effects, but in an otherwise healthy cat, it's very well tolerated. And that will help to reduce the chance that the irritated airways will go into bronchospasm when you introduce your lavage fluid. If you have ever had a cat go into bronchospasm, it's not much fun to deal with.

Give atropine, manually ventilate. Their lungs go literally like concrete. It's very hard to to manually ventilate, but it will go off, so persevere.

But it's much better to avoid it than to deal with it when it occurs. So tibutylin. As in the pre-med, 2 to 4 hours prior to anaesthetic, if you, if you know you're gonna be doing BAL or just before you go ahead, if not, but give yourself as much time as you can for that to work.

And then whatever your anaesthetic of choice, you want to induce the cat, intubate as normal, get the cat onto a nice stable plane of anaesthesia. So the cat's nice and deep, nice and comfortable. And then, ideally put the cat in sternal recumbency.

But if your X-rays suggest that one lung is worse than the other, it makes sense to lie the cat with the poor lung downwards, partly in order to have the better lung, better aerated by being on the upper side, but also because you're Food will tend to drop down to the dependent lung. You're going to do it. This is a blind wash technique, but if your worst lung is downwards, then gravity will tend to take the fluid downwards and hopefully you will be sampling the more affected side.

So generally, I would do this internal recumbency, but as I say, if there is a lot of lateralization on the X-ray, you might want to put the worst side down. And then once the cat is really nicely deeply asleep, we're going to take out the first tube that we used, and we're going to replace it with the sterile ET tube, which we're going to use in order to guide our, our lava tube through the mouth to prevent contamination. And we want to minimise contamination of that tube itself.

So again, we need good technique to pass it through the mouth and through the larynx with minimal, contact. So a good deep plane of anaesthetic. Allow time for your local anaesthetic ray to take effect.

Good positioning of the cat. Use a laryngoscope, even if you don't normally use a laryngoscope, I'd recommend that you do in order to be able to see the larynx and pass the tube through without contacting the sides. And this picture is showing, the, the veterinary nurses pulling the skin of the, the skin over the, larynx downwards.

And what that does is help to open up the larynx so that you can pass your ET tube through again, with minimum contact to the mouth, the pharynx, and the, and the larynx. So then once you've got that tube, that sterile tube in place, and again, the cat is nice and comfortable under anaesthetic, we're gonna go ahead and do our lavage and I've got a video here, real time video just to show you how quick and straightforward this is. So we're going to obviously temporarily remove the anaesthetic circuit.

We've got some induction agent here in case we need to deepen things down. We're going to introduce our end opening tube all the way down until it reaches an end point. You see how far it goes down.

Don't panic. Just gently introduce it till it reaches a natural endpoint. Then in goes our 5 mils and my assistant is tapping the chest to loosen the mucus.

And then when we suck back just negative pressure on the syringe and a little bit of a jiggle of the, of the tube in order to clear any vacuum. Often what happens is, as you suck back, the, the bronchus kind of collapses and, and you get a, a vacuum. So just a gentle jiggle while you maintain a mil or two of negative pressure.

We'll keep, we'll, we'll, we'll get things moving again. And then what I'm trying to show here, and I might just show that again, because it is just only a short video. What I'm trying to show is that you need to keep the negative pressure on as you withdraw the tube.

And that's why you need a 10 mil syringe with only 5 mLs of fluid, so that you've got that capacity to keep negative pressure on. So there we've reached a nice seal, and you do need a nice seal in order to get a good Levar solution. In goes our fluid.

When we come to suck back. We're just gonna have a little gentle jiggle of the tube there just to free it all up, and then the good stuff comes. But the good stuff is going to be in that tube.

So we need to keep negative pressure on. Don't move, remove the syringe, and then we're gonna fill our tubes through from the tube, the lavage tube. So that is where the good stuff is, and you'll see there it is going into the tube.

The fluid that's actually in your syringe will normally only have been in the dead space rather than be the actual alveolar sample. So make sure that you keep, once you pull the tube out of the cat, you keep the tip upwards, you keep the negative pressure on, and then you keep all the good stuff in the tube. OK.

So then obviously you can reconnect the cat to the oxygen supply and, and keep it well oxygenated through recovery. Keep a close eye. You can get, as I say, bronchospasm in response to, as a, because the irritated airway reacts to the fluid, but that is much less likely to happen if you've used tebutyline and if you use warmed saline rather than cold saline, which is quite a shock to the lungs.

And of course, you also need to watch out for fluid or mucus in the T tube, which will cause a lot of noise. You'll hear it. Your capnograph will certainly show it.

But you may need to reintubate with yet another tube if you get a lot of mucus and debris in that ET tube. Usually you will only get back around 1/3 to 5 of what you put in. So if you put 5 mLs in, you will normally only get 1.5 or 2 back, sometimes even less than that.

It should be slightly turbid. And you should see a little bit of froth on the surface, and that is surfactant. And that is what tells you that you did get a good alveola sample, and it isn't just a bronchial wash.

It really is a broncho alveola lavage, and that's really what we, what we need. You may get some blood, I think you saw in that video that there was a little bit of blood. Don't worry about that as long as it's only a little bit.

And then, as I say, we're gonna collect our fluid into a combination of EDTA for cytology and plane tubes for PCRs and culture. And what we expect to find in chronic bronchial disease, we expect to find that there is inflam that there are inflammatory cells there. They may be a mixture of non-degenerate neutrophils, along with a few macrophages and so on, and that would be typical of chronic bronchial disease, or you may get a predominantly eosinophilic, infiltrate, which would be typical of your of your classic asthma.

There may also be some secondary bacterial infections, so you may get some degenerate neutrophils and some phagocytosed bacteria, and that can make it quite difficult to differentiate a pure bronchopneumonia from chronic bronchial disease with secondary inflammation. And it's relatively common if you do PCRs, it's relatively common to identify mycoplasma in the sample. And it's difficult to interpret that.

We very, very commonly find mycoplasma in the nose and in the mouth, the oropharynx, and if you do tracheal washes, you will commonly get mycoplasma there, and we don't consider that to be, a significant pathogen, just an innocent commensal. If we find it deep down in a proper bronchoalveolar lavage sample that was reasonably sterile technique that we don't believe is an oral contaminant. Then it probably is significant as either a primary or secondary pathogen, and it would appear that in some cases it can actually be a primary pathogen.

And therefore warrant, certainly warrant treatment, usually with doxycycline. It's interesting that in humans with asthma and chronic bronchial disease, mycoplasma seems to promote increased airway reactivity and make asthma signs worse. So even if it's not the primary pathogen, even if there is underlying inflammatory disease, managing and treating the mycoplasma probably is still worthwhile, if we're confident that it's a genuine finding from down in the lung, and as I say, not just an oral contaminant.

OK. So I appreciate that you will not always have the luxury of bronchoalveolar lavage. You very often will need to treat on the basis of clinical signs and hopefully, at least a chest X-ray.

But I think if you do have the opportunity to do bronchialveolavages say it can be quick. It is very straightforward. Generally, the cost to the owner is more in the laboratory fees than the actual procedure fees because as say if you have the cat anaesthetized for chest X-rays, it's quite a, a, a simple additional step with no fancy equipment needed.

So, having made the diagnosis, how we're going to treat cats with chronic bronchial disease? Well, it's very important to reduce exposure to airway irritants. So we need to think about cat litter and cat litter dust.

That's probably the most, the, the biggest exposure these days that cats have to, to dust. Cigarette smoke certainly can be a problem these days, hopefully, much less than it used to be, because so, so, so, you know, fewer people smoke in their, in their own homes these days, but obviously, it's still worth asking the question. House dust and pollen can be significant contributors as well.

So we want to reduce the exposure to airway irritants as much as we can. Think about changing the cat litter to a dust-free type. Or to a different type of literary, even if it's a corn-based one, think of moving to something maybe paper-based, or wood pellet based to reduce the, the, the airway irritation there.

And then, of course, corticosteroids are an absolute mainstay of treatment. Potentially with the addition of bronchodilators at times, but as we'll see, we don't use bronchodilators as a mainstay of treatment. We use them as, as adjunctive treatment in severe cases or in, in periods where a cat is having a particularly, difficult time.

And of course, we have a choice of routes of how we will medicate. We can use the traditional oral route for the steroids, or there is, of course, the inhaled route, which we'll we'll come on and talk about. And to some extent, the choice is going to depend on how well the owner is able to give tablets.

Some owners will find that quite straightforward, especially if they can give in food, others will find tabletting their cat a real difficulty. Many, many cats will learn to accept the inhaler and the face mask, as long as we approach it in the right way, which we'll, again, we'll come on to. It is a lot more expensive, unfortunately, to treat via the inhaled route.

And so for many owners, that may be a significant consideration. The, the spacer, the, the mask and, and, and, and spacer are not that expensive to purchase as a one-off sort of purchase, but unfortunately, the, the inhaled medications, the flixotide, you know, it's a lot more expensive than good old fashioned prednisolone. And we need to be aware that we genuinely, we are going to be thinking about long term, indeed lifelong treatment for a lot of these cats.

So, so the cost of ongoing treatment is something we need to be aware of, and the practicalities of, of, of how we administer. But we also need to be aware that this cat is then, it's usually a young to middle aged cat. It is going to be on steroids for a long time to come.

And we do know that if we can deliver the steroids via the inhaled route, that will very significantly reduce the overall exposure of the cat to steroid on a daily basis, but of course, more significantly on a lifetime basis, if we can use an inhaled rather than a systemic route. I haven't really talked about it in detail, but the, the, the, the cat you saw at the beginning, Alfie was on intermittent injections of Depomedrone. I think the concern, the problem with that is that you tend to not get a a a steady state of control of inflammation.

You have control of inflammation, which then wears off, inflammation, mucus builds up, then they get another injection, which perhaps brings it back under control. But that cycle of inflammation building up does leave them vulnerable to secondary infections and indeed to that mucus plugging and lung low collapse that you saw with Alfie. And so I really would advocate trying to avoid intermittent injectable treatment, quite apart from the the inability to titrate the dose effectively.

So again, you tend to end up with a higher lifetime load. So orally or inhaled, absolutely by preference. We usually start with oral treatment because even if we're going to move to the inhaled therapy, it will take a little time to acclimatise the cat to the inhaler and the and the face mask and so on.

And we want to get control of this inflammation as soon as we can. So we start with prednisolone, anti-inflammatory doses, so 0.15 to 1 milligramme per kilogramme, once or twice a day.

But to be honest, it would be very rare to need as much as 1 milligramme per kilogramme twice a day. My rule of thumb, most of these cats actually can be well controlled on even just 1 milligramme per cat per day. So we're down more at the 0.15 milligramme per kilogramme range.

You might want to start a little higher than that, especially if the cat is in a, a Severe attack, but you should be able to control the signs with really quite a low dose. And you should see a rapid response. If you do not see a rapid response to corticosteroids, you have to question your diagnosis, whether there is a secondary infection or whether in fact, there is actually some other underlying cause of the, the cough.

So a rapid response, allowing you to then taper the dose to the minimum effective dose for long term and as I say, very often that is somewhere around the 1 milligramme per cat per day dose or even every other day. Bronchodilator, as I've alluded to, they can be very helpful in acute asthma attacks. They open up the airways to allow the cat to to to the the expiration phase to be easier and, and relief full, .

Again, we only use them for short term use and certainly not on their own. We, the, the primary problem is the inflammation. We need to control the inflammation.

If you only use a bronchodilator to open up the airways, all you will do is allow the inflammation and the mucus to work further down, deeper into the lung and be more likely to cause bronchial bronchial blockage and air trapping and so on. So bronchodilators is an adjunctive treatment along with the corticosteroid, but not as a first line therapy. And in the UK, we have CventileD as a licenced product, not licenced for cats, but licence for dogs.

So that's theophylline. But it's dog capsule 100 milligrammes, so it's quite difficult to, fraction that down to a suitable cat dose. So the other alternative is to use, tebutyline, which I've already alluded to as an injectable, as a means of preventing bronchospasm.

It's Also very effective in as an injectable in acute asthma attacks, and it comes as a 5 milligramme tablet. So again, we can break that tablet down for, for, for, for oral use short term if we need to. And then there's the option of the the Araca inhaler.

This is a little video from of an owner using this obviously in a cat that is by now well acclimatised, so we can see that the soft rubber mask fits over the nose, allowing him to breathe through, and you can see the little valve there is moving as he breathes. So We know that he's taking good breaths, and we know that he's getting the, the, the drug in. You can see the way the owner's holding him, just gently cradling his body against her body, so that if he does go try and go backwards, he can't.

She's just using both her arms to restrain him, but it still allows her to gently hold the mask in place. And a lot of cats, most cats will learn to tolerate this, and it can be a very useful long term treatment. But we do need to introduce gradually and not, in a way that is going to frighten the cat in a way, not in a way that is going to give the cat an aversion to the mask and the procedure.

So I'll come a little more detail to this, but acclimatise slowly, let the cat take as long as it needs to get comfortable. Let the owner take as long as they need to get comfortable, because it is quite a, you know, quite an ask in the, in the first scenario. And if they rush at it and try and force the mask onto an unwilling cat, then that will just build up a fear reaction, and it's unlikely that they will be able to subsequently overcome that.

So things like putting little treats in the face mask, smearing a little bit of Marmite or a little bit of fish paste or something like that onto the mask so the cat can lick it off, and the cat can get comfortable with the look, the smell, the feel of the mask and of it having it around its face and nose. You need to let the cat get used to the sound of the metre dose inhalers. It makes a kind of noise as it goes off.

A lot of cats are quite scared by that. So the owner needs to just get the cat used to that by just activating the MDI when the cat is relaxed and perhaps eating a treat or being groomed just to get it used to the sound, and then a gentle introduction of the whole kit in order to allow the cat to be treated in a, a stress-free way. And again, because this period can take time, it makes absolute sense to start with oral medications to get the clinical signs under control, and that gives the owner the confidence and the time and the space to take as long as it takes to let the cat become acclimatised gradually.

So the inhaler very much the long term, gain, and therefore worth taking a bit of time at the beginning to, to try and introduce it in a, in a successful way. What are we going to put through? We can use both steroid, usually fluticasone in the UK, Flixotide is the is the trade name.

Comes in two sizes, 110 mcg puffs or 250 mcg puffs, and usually we start with the lower end of that range, again, usually twice daily initially. And some cats will need the higher end of the range, but many will be well controlled by the lower end and once well controlled, even a once a day dose may be sufficient to maintain control. We can, of course, use bronchodilators, so salbutamol, Ventolin, again, is the UK trade name.

And 90 mcg is the standard puff. But this we're gonna use when needed and only in short bursts, so maybe for 2 or 3 days at a time, if the cat is having a particularly bad period. Because actually long term use may in fact promote increased airway inflammation and increased airway reactivity, which obviously is, is counterproductive.

So we use it as a rescue treatment, not as a daily therapy. And if you need to give both, so if a cat is usually on the corticosteroid and then needs some bronchodilator, it is best not to try and put them both into the space mask at the, the, the spacer at the same time because they, they will, in, in, you know, they, they will knock each other out of, of, of suspension and indeed just changing the philtre over and so on will be problematic. If you're going to do both, so, it makes sense to give the bronchodilator first to open up the airways.

And then hopefully, when you give the steroid, it will be able to get deeper down into the lower airways and into the smaller airways because the bronchodilator has opened them up. So bronchodilator first and then corticosteroid maybe 5 or 10 minutes afterwards to get best effect. So I've touched on the importance of introducing the face mask and the space bar gradually.

Breathe Easy, have some really nice owner oriented materials that you can direct owners to to help them in that process to give them some tips and tricks. And you can access those through the website or of course through your, your. Your, your local representative.

So here we've got tips on getting started with inhaled therapy, making it a positive experience, conditioning the cat to the idea, so slowly and calmly familiarising them with the chamber and with the, the face mask and so on before you try to start dosing. Giving them lots of hugs and pets and cuddles before, during and after treatment with cats. When we train cats, we use positive reward all the time, a positive reinforcement, certainly not a negative reinforcement to train cats and a treats before, treats afterwards, reward them for good behaviour in inverted commas, reward them for a successful treatment so that they really get to, think of it as a positive and actually, accept the treatment very nicely.

So creating a positive response to the chamber, create curiosity in the chamber, light on the ground, hold it at a distance, let the cat come to it, let it sniff it in an unthreatening way. Keep it still and let them have a, a, a good explore of it. Again, treats, hugs, and play.

And I think it can be really helpful to either encourage the cat to play with the device or to, as I say, to, to put treats in the device or smear, something, as I say, like cream cheese or Marmite or whatever it is that the cat loves on the face mask. Not when, with, without it being attached to all the, the rest of the paraphernalia, but just getting them you. To that face mask before the relatively, unwieldy, chamber gets added onto it.

And owners need to get used to the handling of all of this as well. They need to get used to being able to support it gently in a one-handed way, and be able to hold it in such a way that they can, activate the metre dose inhaler while still holding the chamber and still holding the cat. So, just a bit of practise, will reap reward.

And then some tips for owners on how to actually introduce the actual medication. So keeping the device on your lap while you call the cat to you, enticing them again with your treats, keeping them, keeping the little bit of, of treat on the mask to encourage them to accept it on their face. And for some cats, actually just gently swaddling them in a towel.

Or a blanket can be helpful, but we're absolutely not talking about a tight towel wrap here. This is just a very gentle swaddling, cuddling in a, a, a familiar blanket so that they feel cuddled. Definitely not a, a tight wrap, which will absolutely instil fear for the next time and, and build up trouble.

And then just the final chart that that Breathe Easy have have produced for us just with some reminders of dosing. And again, encouraging this concept that we're going to, if, if the cat's in an acute state, we're going to use injectables to treat the cat to get it out of that state, unless it's already acclimatised to a face mask, and the owner has steroid and or salbutamol at home, in which case, absolutely they can step in at home. But by the time the cat gets to the clinic, it's usually better to use injectable dexamethasone and or tebutylin in an acute asthma attack.

And then we're gonna gain airway control and clear inflammation by using oral steroids, as we've outlined, while the cat transitions to the use of the inhaler while it gets used to the inhaler and gets to a point where it will accept medication by that route. And then we're gonna actually probably overlap therapy for a couple of weeks as we transition. So while we are tapering the systemic steroids towards stopping them, we are also going to be using the inhaled route to gradually build up control that way.

And in doing that, you can get good rapid control of the disease to keep the owner happy, but also transition to the long term. Inhale therapy, which, as I say, over a lifetime will will much reduce the cat's overall exposure to steroids if the owners are able to commit to daily management by that route. But we do need daily therapy for symptom management to avoid that cycle of inflammation building up to a point at which the owner finally does present for treatment.

And then we get the inflammation under control, but potentially those those, those complications of either bacterial infection or airway trapping and lung collapse may already be underway. OK. So I hope that's been a, a kind of useful overview, a bit of reminder of some aspects, and, you know, an introduction perhaps to some, some, some new ideas and thoughts.

I hope it's been helpful. I hope it's been practical. I know the recording will be available if you, want to review it for doses and these charts, but as I say, these charts are also, of course, available from the Breathe Easy website if you want to, access them for your clients.

Martha, thank you very much. That was an absolutely amazing webinar. And once again, you'd never let us down with a fantastic insight into these, these topics that you speak to us on.

So thank you so much for your time. A big thank you to our sponsors, Breathe Easy. As you can see at the bottom of the screen there.

The website is there, and, they would be more than happy for you to get hold of them and get more information on their products and this fantastic chart that Martha has left up for us at the end. Martha, I was quite pleased to see that your two new terrorists behave themselves. They've been, I, I should say to the audience, I, I, I'm a very, very proud and happy owner of 216 week old kittens who are actually sprawled in front of me on the, the window sill.

I thought they might be rampaging around and, chewing cables and jumping on laptops, but they have been extremely well behaved, so yes, so thank you, thank you to them for that. Martha, we've got loads of questions. Folks, we're not gonna get anywhere near all the questions tonight.

And in fact, I've just picked out 3 that I think we'll answer because we have run over a little bit, but I, I do like these 3. The first one comes from Gillian, and she says, would you use turbutyle as a pre-med for BAL if radio graphs hadn't previously been taken, i.e., will it affect the diagnostic of the radiographs?

OK, interesting. No, I don't think you need to to worry about that. The, particularly the, the, the bronchial pattern is, is due to the inflammation in the airway wall.

. The, the, the, you know, the increased mucus lining and the, the, the increased peribronchial infiltrates, which will not be affected. Corticosteroid, potentially, yes. Although even, you know, I think a single short acting injection just before you take your radiographs would not have too much of an effect.

But if, if this was a cat that had come in, in an acute asthma attack and had been given steroid and then gone home with some steroid. And then you take your X-rays a few days later when the crisis is averted, which would be a very sensible approach to take. Then I think the steroid could certainly, mask some of the signs, but no, I don't think, the bronchodilator would.

Excellent. The next question obviously is one that assumes that the cat is not on, oral steroids and is on an inhaler. But they talk of, the, the person has asked here, whether you can use meloxicam because in humans, it's been shown to be a non-selective inhibitor of prostaglandins that normally would help with bronchodilation.

Mm. I think there's, there's always a, a, a, a big question about how safe it is to use non-steroidals along with either topical corticosteroid or inhaled corticosteroid, and I think we have to be aware that via the inhaled route, we will still get a degree of systemic absorption. So that, you know, there will be some overlap.

So I think we do have to be quite cautious. But saying that, if I do have a cat that needs, non-steroidals for its arthritis, it's chronic pain, whatever, and it needs inhaled steroids, I certainly have used the two together. I'm not sure I'd go so far to say that, that, that, that the, that the non-steroids will help with managing the chronic bronchial disease, but, but if we need to use the two together, certainly clearly, I would not do that with oral steroid, but, with inhaled steroid, I, I, I would, in fact, I'm, I'm Thinking of a little cat that I'm, I'm treating at the moment that has both kidney failure, severe arthritis, and now, lymphoplasmocytic rhinitis, which is quite an unholy combination.

So, she is on her meloxicam for her arthritis, because her kidneys are stable enough, we can safely use that. But for her lymphplasmacytic rhinitis, I've actually started her on inhaled steroids. She's obviously breathing them in through the nose.

And most cats will breathe through the nose and when the mask is on, and that is controlling her lymphoplasmacytic rhinitis very nicely. So, you know, sometimes we're forced to make some compromises like that, but nevertheless, still be cautious because there is some systemic absorption. Excellent.

The last question is, what about antihistamines if this is an allergic condition? Yeah. Certainly some cats, if you genuinely have asthma, and of course you do need to make the distinction because they, they won't have any benefits at all for for chronic bronchial disease.

Some cats will gain some benefits. But again, I would be, I would be cautious to use them in place of corticosteroid, just because I think control of this inflammation is, is so important to prevent, those, those chronic complications, the secondary infections, and the, and particularly that, You know, that the, the emphysema or the collapsed lung lobes. So I, I would think, I, I think it would rarely be sufficient on its own, but it might be a way that you could, if you weren't able to use an inhaler, it might be a way that you could reduce the amount of steroid that you needed.

Excellent, excellent. Martha, one question from me. Alfie, did we need for the lung lobectomy?

No, I perhaps should have made that clear. They, the, the other lungs, hyperinflate to fill the gaps. The, the collapsed lobe gradually kind of shrinks down.

And in fact, in, in his case, it had been about 6 weeks since the episode. And so on that x-ray, you could see, that the, It was already starting to collapse down. So it's the right middle lobe.

It's quite a small lobe. They will function very nicely on the remaining lungs as long as the remaining lungs are maintained in a healthful state and not becoming emphysematous and obstructed themselves. Absolutely fantastic.

Martha, we have got nearly 30 comments coming through our fantastic webinar. Thank you very much. As Anthony would always say, if we were in an auditorium, you would have heard thunderous applause.

Thank you very much. Thank you for your time. We really appreciate you sharing and you want to come back to the webinar.

Welcome you with open arms. Thank you very much. You're, you're very welcome.

And again, I hope it's been useful. I hope the number of questions doesn't imply that I have confused and bamboozled you. I hope it just means I've wet your appetite to think about what is perhaps sometimes considered a rather mundane condition, and, you know, shone a bit of a light on perhaps under, under considered area.

Now, excellent webinar. Thank you so much. And once again to our sponsors, Breathe Easy.

Thank you very much for your sponsorship. To Dawn my controller in the background, thank you for making everything look effortless. And from myself, Bruce Stevenson, it's good night.