Hello, and I'm glad for those of you that have stayed, well done. So we're gonna, we're gonna have a chat about how to investigate and treat Pseudomonas otitis in dogs. So it's a big problem in dogs.
So that's what we're going to focus on. So we're going to start with a brief introduction to Otis, then we're going to talk about the aetiology of it, what clinical signs we might see, investigations that might be useful. We're going to talk a little bit about otitis media, because I think that's where people start to worry and panic about what they should be doing.
And then we'll talk about ear flushings and treatment options for specifically for pseudomonas cases. So otitis is a really common clinical presentation that we see in practise. So I certainly see a lot of it in referral practise and used to see a lot of it when I was in first opinion as well.
I think it's important to realise that there's usually always an underlying cause in cases where the otitis is recurrent. So often in the pseudomonas cases we're presented, often they do have a history of having had a mild or recurrent otitis. On several occasions.
The aetiology of otitis can be classified in different ways. So there's 4 main things we need to think about. So there's predisposing factors.
These increase the risk of otitis externna. There's primary factors, which are the things that directly cause otitis externna. There's secondary factors which don't create disease in normal years, but they can aggravate it.
When it's present. And then there's perpetuating factors, and these are the things that are related to when you've got chronic otitis, you get change in the structure of the ear or disruption of the normal physiological function of the ear. And this means that the otitis never completely goes, like a lot of our pseudomonas cases, they keep coming back to haunt us, and it's a constant problem.
So we'll just have a look at the predisposing factors. So the confirmation of the ear is, is an important predisposing factor. I've put a picture of a Basset hound there.
So we're thinking about the dogs that have got the, dangly down ears, where they, they might become humid and you get less air flow. So that is thought to be a predisposing factor. In increased humidity in the ear.
I think it's important to realise that inappropriate cleaning can be a predisposing factor. So often owners think they're doing doing the right thing by Cleaning these ears, . Repeatedly or using solutions that the breed is recommended, for example, and they can actually cause irritation and then predispose the dog to developing otitis.
Hairy ears can be a predisposing factor, a predisposition to sebera, and irritant treatments and overtreatment can also be a predisposing factor for otitis. So sometimes we can be guilty of of doing those things and trauma to the ear, such as if they've had a grass seed and it's traumatised the ear canal or plucking the ear canals, for example. Neoplasia is also on this list, but it's more something that you would see in older dogs, or very young dogs with polyps occasionally.
So let's have a chat about the primary factors. So these are the things that will cause otitis in their own right, and right at the top of the list, following on from our previous lecture is allergic skin disease. So that includes food allergy, atopic dermatitis.
Those are definitely one of the most common causes of recurrent otitis in dogs. We obviously also have ectoparasites, so things like odectes, and we will on occasion find demodex causing a seruminous otitis, so it's worth bearing that in mind. Foreign bodies, grass seeds, most commonly.
Tumours of the ear canal, an underactive thyroid. This is worth bearing in mind if you're presented with an older dog that suddenly starts getting recurrent ear infection. So sometimes that can be the first sign of the hypothyroidism.
Coatinization disorders, so these are the sort of things you might see in cocker spaniels, where their skin turnover is very quick. And autoimmune disease. But by far the most common is allergic skin disease.
So the secondary factors, these are the things that we often focus on as vets treating these, this condition, but they aren't the thing that's actually driving the otitis. So, although this is what we're trying to get rid of, we need to remember that we need to be looking at why it happened in the first place. So the most common thing, secondary factors are yeast, so malathia is shown in this picture, or bacterial infection, and that would include any staph pseudomonas.
E. Coli proteus infections in the ear. And then we've got the perpetuating factors which are the things that make the otitis difficult to get rid of.
So epidermal and spatial hyperplasia. So if you've ever looked down at ear and you've seen that sort of knobbly. Sort of bumpy appearance to the canal that should be nice and smooth.
That's because you've got chronic inflammation causing this hyperplasia. Ulceration, which is a very common clinical sign that we see, especially with Pseudomona, that can make these cases difficult to treat. Otitis media, so when we get infection in the middle part of the year, that's also a perpetuating sign.
So if you've got a dog with recurrent otitis, it's always worth thinking, should I be imaging it to look for otitis media. So when we're presented with these. Patients with ear disease, we see obviously a variety of clinical signs.
So the common clinical signs, most common reports we get from clients when we say what clinical signs the dog got, they'll often say he's shaking his head, he's scratching his ears. Sometimes they have a head tilt or abnormal ear carriage. So, things like German Shepherds, for example, often carry their ear at a right angle rather than being straight up and pointy.
That doesn't necessarily mean they've got neurological signs, but obviously we can see, head tilts when dogs have got otitis media as well. There may be some discharge. It may smell, sometimes that's the first thing that alerts owners to a problem.
It can be painful. And sometimes they have discomfort when they're opening their mouth, especially if they have got otitis media. So we've certainly seen some dogs where their main presenting sign for the client is they've stopped chewing their nylo bone and they yelp when they pick it up or when they stop catching their tennis ball.
So that's something to bear in mind. So what do we do to investigate our otitis cases? So there's lots of different things we can do.
So it's really important that we get a good history and do a full dermatological examination as a starting point. So sometimes the history of the otitis can give us a clue as to what's going on. For example, my dog was fine, I ran it through a long field of grass yesterday, and as soon as it came back, it started shaking its head and it hadn't stopped.
That would make us think, oh, maybe there's a foreign body in there. Looking down the ear is probably important. Has the dog got other signs of skin disease because we've already said otitis.
One of the main primary causes is allergic skin disease. So has that dog got other signs of skin disease? Does it lick its feet?
Does it rub its face? Does it itch anywhere else? And that's why we want to get a full history, and that would include a dietary history as well, because we do see recurrent otitis certainly is common to see it with food allergic patients.
And then we want to examine the whole dog's skin. So. Likewise, it's not uncommon for you to focus in your short consults, which, you know, you have a limited amount of time to focus on the ear, but it's just worth bearing in mind if there are other signs of skin disease and that makes it your job easier in a way to work out, it's probably got allergic skin disease and that's probably what's going on.
So this was a little dog called Roxy. Who I saw quite a long time ago now. And she presented with one ear that looked like this.
So you can see very thickened, alopeciic, excoriated. We took a full history from the client who reported no other signs of skin disease. But then when we looked at the dog, we saw this on her carpus.
So clearly, this dog has got other signs of skin disease, but the owner's been so focused on the ear, they just haven't noticed anything else. And that dog ended up having ectopic dermatitis, and then once we've managed the AP, the ear disease wasn't recurrent. So the other thing to think about is when we're examining this dog, otoscopy.
So something that we're always told that we should be doing when the dog presents with otitis, but it can be really difficult. So if you've got a dog with a painful ear with pus pouring out of it, it can be really, really difficult to even think about getting an otoscope near to that dog's head, let alone in its ear. So I think we need to think about what we're trying to achieve by doing otoscopy, and we should always be considering whether or not we should be sedating these patients if they're really painful and we think it's vital that we need to look down today.
I think realistically, if you think about Doing otoscopy in dogs with a sort of purulent otitis, when you put the otoscope down. All right. OK, thanks everyone for staying with us.
Lovely, thank you very much and sorry again. All right. So we're just to recap, so we're just talking about otoscopy and how useful or not it can be.
So I think if you've got a foreign body, it is useful if you can see that, or if you're looking for tradies, it's useful. If you've got an earful of pus and you're trying to see the eardrum, then that may be less useful. But it obviously can give you some idea of the stenosis of the canal.
So if you've got a really, painful dog, then maybe either consider sedation or maybe consider that that's not the best diagnostic. Step to do at that point if it's really painful. Cytology, on the other hand, is always very, very useful.
So it's useful for us to know what's in that ear. So often that'll be the first thing that I do with my patients, rather than going in them with an otoscope. Most dogs seem to be quite happy with you getting a sample of the pus to have a look at under the microscope, more so than approaching them with an otoscope and poking that into their ear.
So, cytology should be done in every ear case, in my opinion. If you're not confident at doing it, start doing it, start doing it and sort of build up your confidence, or try and train up one of your nurses, because the sooner you start doing this, the sooner you're going to get better results with your ear cases. So the reason it's useful is because it enables us to know what bugs are there.
So have we got cockeye? Have we got rods, have we got yeast? And then that enabled us in turn to make a better treatment decision or to decide when we're gonna send a swab for culture.
So generally, generally if we've got yeast, we wouldn't send a swab for culture because it's not gonna add to our information. But if we've got bacteria, so if you've got rod-shaped bacteria, especially, we're always gonna culture. So I think if a lot of pseudomonas cases, often that's sort of a later down the line.
So they've probably had an infection, maybe a yeast otitis, and then that's progressed into a pseudomonas. So I think it's useful if you follow these cases up with cytology every time time you see them, you can see what the changes are and whether your treatment's effective. So I really can't stress how important enough, how important cytology is when you're managing an ear case.
So we'll show a video. It may be a bit jumpy like the others, so I'll talk you through it. So when you're taking a sample for ear cytology, this dog isn't dead, it's just sedated.
You're gonna pop a cotton bud into the ear canal and just get a little sample of the pus. Now this dog had a very mild malaysia otitis, so obviously if there's puss right at the external auditory meatus, you can get a sample of that. And then what we would do with that sample is we would gently smear it on a glass slide.
So just roll the cotton bud on the glass slide. Try not to be too rough or you just distort the cells, . And makes your sample harder to look at.
So once you've done that, just let it air dry. I know some people heat fix their slides and all sorts of things that you can just let it air dry and then you'd be ready to stain that to look at it under the microscope. So then we want to stain our sample.
So again, this can be challenging. So I stain my sample in all three stains. So I do 51 2nd dips in the fixative, 51 2nd dips in the red stain, and then 51 2nd dips in the dark purple stain.
So I know a lot of people with, when they're staining ear cytology will only use the deep purple stain. This is where I was trained. I stain everything the same, whether it's a tape strip.
Or an ears smear, and you know, stuff doesn't dissolve off my slide. I still see plenty, so. If it's easier for you to remember to do everything the same way, that's fine.
So once you've dipped it to all the stains, you're then gonna rinse it under the tap. So we want to get rid of all that excess blue stains. So really you want to rinse it until the water runs clear.
You can run water off the front of the slide, you've fixed it so that sample isn't going anywhere. And then you can blot it dry with some paper towel. So you can literally just wipe the back of the slide.
And then just block the front of the slide with some paper towel to dry it. And you're good to go. And now you'd be able to look at that sample under the microscope using oil immersion.
So that you can see what organisms are present there. You must not under any circumstances rub the front of the slide. This video was made for vet students, so that was to tell them not to do that.
And then always put your lids back on the stains afterwards. So what might you see? So here we've got our classical maesthesia.
So peanut, skittle, snowmen, whatever you would prefer to call it. So that, that would be, that would shape our treatment choice. So we wouldn't send a swab for culture from that because all it's gonna tell us is there's malashesia there, and we already know that.
You might see some cockey and some neutrophils. So these are degenerate neutrophils and you can see lots of cockey. Cocoid bacteria on the slide.
Or you might see rods. So these are rod-shaped bacteria. There's also for the eagle eye of you watching some cockeye in there as well.
So often you will get a mixed infection. So if ever we see rods on cytology, we're definitely gonna send a swab for culture because then we might be suspicious that this could be a pseudomonas case. So what does it tell us?
And how do we use that information? So I think it's important to realise that the levels of antibiotics, they're measuring to do our sensitivities for is the levels that you'd achieve if you administered these drugs systemically, or orally, and not what the levels we achieve when we use them topically in the ear. And topical therapy would be our main way of managing these cases.
So a lot of people. Get very hung up when they get their swabs back, especially from Pseudomonas cases, and it's resistant to everything, and it's only sensitive to it or weird things that we can't or don't use. So try not to worry about that.
But what we really want to know is, is it a pseudomonas? Yes, and we know it's gonna take us a long time to get rid of. It might be more challenging.
And if we've got sensitivity, great, we'll use that product. But if we haven't, then we'll use something that should be effective because we're going to be using it at 1000 times higher concentration than we would if we were giving an oral tablet. And I think now it's important to realise that we rarely treat otitis cases with oral medication unless they've got severe neurological signs, and we're worried about worsening that, by putting something in the ear.
And when yeast are present, as we said, we wouldn't send a sample for culture. The other diagnostic test that can be useful when we've got recurrent types of cases is to do some imaging. So whether that's CT or MRI, radiographs can be useful in some cases, but they do take a long time and the positioning can be quite tricky.
So generally, I would do a CT scan because I'm lucky and I have access to that. They are useful when you've got chronic otitis cases that aren't responding to treatment and you're sure you've got good owner compliance. And they're doing, you know, they, they're not responding because we've already heard that otitis media can be a perpetuating factor for otitis.
And so if that's happening, we need to know, well, do we continue with medical management or is now the time to hand the case over to the surgeons because we're not going to resolve this due to the chronic changes in the middle ear. It's also useful if you've got unexplained swelling or discharging sinuses around the ear or if there's pain when the When they're opening their mouth. So as we said, that can be a sign and certainly we saw a little terrier and it did have a very mild otitis externna, which responded lovely to treatment.
The eardrum had rehealed, but the dog still have pain opening its mouth. So we sent it for a CT scan, and it actually did have quite destructive changes to the buller and a very severe otitis media, even to the extent of it having a meningitis. So I think it's worth asking or noting if there is any pain when these dogs open their mouth.
So let's talk a little bit about our type of media. But this is when the infection extends into the middle ear cavity, and it's usually as an extension of otitis externa. So we obviously are aware probably that cavalier King Charles spaniels can get this primary secretory otitis media, where, which is like blue ear in children, but most of the otitis media we see is an is an extension of otitis externna, which eats a hole through the eardrum and then causes infection in the middle ear.
So we've got a picture here of a normal eardrum. And then a picture of a big hole and lots of puss in the middle ear. So what causes that eardrum to rupture?
And it's basically, as we said, an extension of otitis externa. It can be iatrogenic. So sometimes if you're flushing in the ear, you might accidentally rupture the eardrum, especially if it's diseased already or there's been an otitis present for a long period of time.
We certainly see foreign body penetration causing holes in the eardrum. So grass seeds are quite sharp and pointy. They're quite good at making holes in the eardrum.
Otoecty can do the same. Tumours can certainly invade through the eardrum. And sometimes we see a rupture associated with this primary secretory otitis media in cavities where basically the pressure of the fluid in the middle ear gets so great, it causes a rupture of the eardrum.
It's important to remember that even if the eardrum ruptures, if we treat the infection, they do regrow. So normally within 3 weeks or so, the eardrum can heal. So that's why it's important if there is no type of media, we treat it because we don't want the infection to be sealed back in the middle ear.
So if you're presented with a dog, what might lead you to suspect that this dog's got otitis media? Well, you can't see the eardrum, but we've already said that's really difficult anyway. So that could be challenging.
If the dog's got chronic or recurrent otitis, a large proportion of these cases will have some otitis media. And I think that's worth bearing in mind. So if you've had a dog with otitis that you've been treating recurrently, and you're not getting long periods of time where it's free of infection, then think about that dog may have otitis media as the reason to why you can't resolve things.
If they're presented with neurological signs, that's a very good indicator that there's something, going on in the middle ear. So think about that, and they would be the cases that we wouldn't treat topically, pain or reluctance to open the mouth. And, some owners report hearing deficits, but that's really difficult to assess, without doing a BAER.
And obviously, if you've got an earful of pus, your hearing probably is going to be deficient, whether it's in your middle ear or not. So hearing deficits is often written, but it can be very difficult for clients to. Decide what's going on or for you to know, well is it just because they've got like an earful of pus or is it actually because the middle ear is affected?
So let's, so generally, we have surgical and medical treatment options to manage otitis. So surgical management of otitis could be in the form of a totally a canal ablation and osteotomy or a ventral bula osteotomy. I'm obviously not a surgeon.
I try not to send my cases to the surgeon if at all possible. But when we're presented with something like this dog here, clearly that dog has no ear canal that I can get anything down medically. So.
That one would be what we would classify as an end stage year and surgery would be the correct treatment path for that patient. Sometimes we end up, ends up being recommended for other reasons though. So sometimes it can be that owners just can't apply medical therapy or it's not possible, or it hasn't been effective, in which case, surgery is the correct call.
Sometimes it can be a cost issue. So if you've got a limited amount of insurance money. Whilst we may be able to fix your otitis medically, it might take us 8 weeks, 3 months.
There's no guarantee it's not gonna come back and maybe you've got a limited insurance money, so maybe a tika is what you would elect to do if you were the client. And sometimes you end up using surgery because there's only compliance issues that they can't administer the drops regularly and they just want an end to the problem. So there's lots of reasons that aren't necessarily veterinary reasons, for surgery, but for some clients, that's the best, and dogs, that's the best option.
So it's certainly an option there. For me, it's always a last resort. It's a salvage procedure, and it, you know, often we will discuss it with owners early on, especially when presented with a Pseudomonas case, because they may end up going that way, but most donors generally don't want that surgery that I see anyway.
So then we have the medical management of otitis. And this is pretty intensive. So topical therapy, if any of you have ever put eardrops in your own dog, you'll know it's not always easy.
Sometimes the ears are painful and the dogs aren't very cooperative. So it can and it can take a long time, especially if we're dealing with pseudomonas cases. I generally will warn my owners that this is gonna be 6 to 8 weeks of ear drops and cleaning for longer than that, but twice daily treatment probably for 6 to 8 weeks.
Ear flushing is useful. So under general anaesthetic, that can be really, really beneficial. But these clients are going to need to come back and see you multiple times, generally fortnightly if they've got a severe otitis.
And there's no guarantee that that's going to work. So there's no guarantee that's going to fix the problem, and it might be. Costly for them.
So it is gonna cost them a lot of money. So if we talk a little bit about ear flushing. So there's no rush to flush that ear, even if it's had Pseudomonas, it's got Pseudomonas in it, there is no rush to flush that ear.
So one of the sort of very eminent dermatologists, from America who does, he basically does ears and nothing else, he always says no rush to the flush. And I think that's important to remember because you want to do a bit of preparation before you try and flush that ear to get the best out of your flush. So, Putting them on some steroids before you go to an ear flush is really useful because that's gonna open up the ear canal.
It's gonna reduce the secretions and the inflammation. It's also going to reduce that glandular hyperplasia. So you're gonna have a more patent canal which is going to enable you to do a better flush.
And generally, All of my patients will get prednisolone daily at 0.5 mg per kilo. For at least 7 to 10 days before we would do an ear flush.
So. There there's no rush to do this, you know, it will be beneficial, but make sure you prepare your patient with some steroids first, because it's gonna make your life easier when you go into flush. We also want to know what's in there before we flush.
So for example, if you've seen rods from cytology, it'd be really useful to know by the time you flush is that pseudomonas and what antibiotics should I be using to treat that case. So generally, we would do that before we had the patient in flush the ear. It always needs to be done under general anaesthetic.
So it's a very stimulating, painful procedure, and it needs to be done under general anaesthetic to keep the patient comfortable. And some patients will head shake. If you try and do it under sedation, you're not going to be able to do a very thorough job.
And generally we would do a CT scan before we flushed just so we know what we're dealing with. And you can do that either with, you can flush either using a handheld otoscope as shown in this picture, or with the video otoscope if you have one available. So if you're gonna flush in your practise using a handheld otoscope, generally this is the equipment that I would use.
So I would use saline, I'd have two bowls. I'd have glass sizes and cotton buds in case I wanted to repeat my cytology. I'd have swabs in case I needed bacteriology.
And I generally do this with dog urinary catheters, with the 6 French urinary catheters, and I cut them to length so that they're the right length for me to pass down the otoscope, depending on the size of the dog. And then I would use some 5 mil syringes. I find it really helpful before I even start flushing or looking down the ear to clip all the hair away from the external auditory meatus.
So often we're dealing with a lot of spaniels or spinon, poodles. They've got loads of hair there. So it does two things.
It means that the hair's not going to get all wet and get in your way while you're flushing, but also it enables the owner to see the ear canal, visualise the ear canal better when you discharge the dog for ongoing treatment. So it's quite interesting that some clients don't seem to know where they should be applying eardrops, but they see it much more clearly once you've clicked the ear. So it's, it's a useful thing to do first.
And then we'll examine you, see if there's any ulceration, discharge. You might be able to see tympanic membrane now because the dog's asleep, so you can get your otoscope in properly and have a really good look. Then I would take a swab if I hadn't done it already and make a smear for cytology and keep the swab to send if I needed to, if I hadn't done it in preparation of my flush.
And then I would start flushing. So generally, I've got two bowls, one with saline and one for the solution that I flush out of the ear. And I flush using this urinary catheter and a syringe, and I always suck back the fluid that I put into the ear.
So I'm looking down the otoscope, I removed the magnifying lens and then pass the catheter into the ear canal, flushing probably 2 mLs of saline, and then suck it back. There's lots of different ways to do ear flushes, but this is the way I like to do it. That way you don't get pseudomonas pouring down the dog's face.
But for some people do just run fluids through, so no way is right or wrong. This is just the way that I would recommend doing it. And once you've flushed as much as you can, try and see if you can see the eardrum if you haven't seen it already, and then continue to flush until the fluid from the ear is clear.
And this can take 45 minutes per ear. So, I will, when they're having an ear flush, if they have got very hairy ear canals, I will pluck their ears, but I don't generally recommend plucking, in conscious dogs, because I think it can cause a lot of inflammation and irritation of the ear canal, and that doesn't necessarily help you to resolve the otitis. So we're gonna come on to talking about how we actually gonna treat our pseudomonas, how we're gonna get rid of it.
It's always a challenge. So we've got several things that we need to aim for. So our aims are we want to kill the eliminate the pseudomonas, which we know is a secondary factor.
We want to reduce the inflammation in the ear canal because that's going to change the conditions within the ear, which is going to make it harder for the pseudomonas to keep causing a problem. We want to clean the ear, and then we want to prevent it from coming back by addressing any of the primary predisposing or perpetuating factors that might be present in that case. So Pseudomonas is challenging to treat.
So the things that make it challenging are that often they produce a lot of proteases, and they often these cases will have otitis media. And the organ organism itself is also very challenging because they can become resistant to treatments very, very quickly. And I think because you are continually changing treatments, and they need a lot of follow up often.
Owner and patient compliance can be not so good when they've got to medicate these dogs really, really regularly to get rid of the infection. So the first thing we're going to talk about is how to get rid of the, the pseudomonas. So as I said before, topical therapy would be the mainstay of treatment in these cases, unless the dog had really had neurological signs.
If they have neurological signs, I won't put anything into the ear, but a ruptured eardrum does not stop me from treating these cases topically. And there's two main groups of things that we would use to treat them. So antibacterial agents and then antiseptics and others because I don't know what category to put them in.
So when we're thinking about antibacterial treatment, fluoroquinolones are really, really good. So they've got a good spectrum of activity against pseudomonas, those things we would use for refloxacin or marbafloxacin. These are bactericidal antibiotics that have that are concentration dependent killing.
So. Remember we talked about the culture and sensitivity results, not representing the amount of drugs that we're putting in the ear, because this, these antibiotics work by concentration dependent killing. We're putting them in 1000 times more concentrated than that swab has indicated.
So if it said it's resistant, it may not be resistant when it's 1000 times more concentrated. And the other thing we can also think about doing is using Tri CDTA half an hour before we put these drops in to try and potentiate the effect of the, of the antibiotics. So Tri CDTA is very good at sort of punching holes in the bacteria and enabling better penetration of the antibiotic.
So it's a very good pre-treatment solution, especially if you've got a multi-resistant pseudomonas. And they can be used for loans, but really if you can use them topically, that's probably a much better use of. The drug because you won't get very good penetration into the ear canal by giving them orally.
But obviously, if the dog's got neurological signs, and you can't treat topically, then you may need to use oral treatment. Other antibiotics that could be effective, polymix in B, which are probably all familiar with in trust the old Suraan. I find in the cases that I see that clinically it doesn't seem to be as effective as it should be on paper, but that may be that a lot of the cases that we see have been very chronic and going on for a long period of time.
So I'm not saying don't use it. I'm saying in my, in my hands with the selection of cases that I see, which are obviously You know, the, the tricky ones that haven't got better, I don't find it as effective, but they've only just got that product in America and they all think it's amazing because it's killing everything. Obviously, it's been here a really long time.
So that might be why we find it less effective. The other group of antibiotics that can be useful are the aminoglycosides. So gentamicin is really, really good at killing pseudomonas.
Again, it's concentration dependent killing as with the fluoroquinolone, and it's essentialiated by Tri CDTA. So in the same way as the fluoroquinolones are. A lot of people worry about gentamicin because they think it's autotoxic.
It is autotoxic when it's given systemically. It doesn't topically it doesn't seem to have the same effect. It may affect hearing slightly.
But if the dog's got a resistant infection in there, it's hearing's probably already affected. So you need to take the balance of that, but it doesn't cause profoundo toxicity like it does if you give it systemically. And we've got a group of antiseptics, so, acetic and boric acid has been reported to be useful as a soaking affected ear.
So once you flush the ear, if you fill the ear with an acetic boric acid solution and then leave it in there for 5 or 10 minutes. And then flush it out again. That can be really useful to manage these tricky pseudomonas cases.
And we've talked briefly about Tri CDTA as a pre-treatment solution. So this has got a pH of 8 for CDTA, so it can be quite irritant to some dogs. So that's worth bearing in mind.
So it's not something we would use as a routine cleaner, it's something that we would use as a pre-treatment solution when we're dealing with really resistant infections. And ideally you would use it half an hour before they put the drops in. So these poor clients, not only they got do drops twice, but they've got to do two lot things each time and allow a gap.
So that can be really challenging to get some clients to do that. And then silver sulfadiazine or flamazine cream. There are studies to show this is very effective in pseudomonas cases.
And you mix it up with saline, and you can apply that sort of emulsion suspension to the ears and that can work in some cases as well. So what do we do if the eardrums ruptured? Well, there's no licence treatments to deal with otitis when you've got a ruptured eardrum.
There are several off-license treatments that we use. So the thing I most commonly use is a mixture of a injectable or refloxacin injectable 2.5% with water for injection at a 1 to 4 ratio.
And I would use that twice daily in an in an affected ear. Even if the eardrum was ruptured. So it is off licence.
I always warn owners if I'm using an off licence treatment that it's off licence, get them to sign a consent form, and also discuss with them what might happen if it causes a problem in the middle ear. So if the dog tilts its head or starts playing with neurological signs there to stop the drops and contact the hospital straight away. Thankfully, that doesn't happen very often in in docs.
So. I'd be, I wouldn't be using any of these things in cats, but in dogs, they seem to be pretty resistant to having neurological side effects. You do see occasionally, but it, it's uncommon.
The other thing we can use a genoin ear drops, which is gentamicin, water-based solution. The flamazine is reportedly safe and triol is reportedly safe if you've got a ruptured tympanic membrane. The combination of those things, and it's unusual for me to use anything other than those things if we've got a resistant infection.
It's really important that we address the inflammation in the ear canal. So steroids are important and I think often they're overlooked and people are worried because you've got a multi-resistant infection and you're giving the dog steroids. I think bear in mind you're giving an anti-inflammatory dose of steroids, and you need that to reduce some of the perpetuating factors.
You need the inflammation to reduce, you need the ear canal to open up, because not only will that make it easier for the owners to administer the medication, but also you're removing that knobbly bobbly surface, which is like a perfect conditions for the pseudomonas to, to live in. So do it before flushing and then continue with the prednisolone or steroids after flushing. And also think if this dog's got allergic skin disease, you'll be managing that as well, which is probably why the otitis has started in the first place.
Analgesia. These dogs are often really, really painful. I tend to use opiate-based products, so Pardale, post ear flush, and in the early stages of managing these conditions.
My experience with non-steroidals is I can't use them because the dog's on steroids anyway. But if, if we see dogs that are on non-steroidals, they don't really see. To be giving these dogs much pain relief, from the pain they're getting from their otitis anyway.
So I would avoid non-steroidals, and think about using, paracetamol, codeine-based products for a few days, while you initially start treating these cases. So ear cleaning is also really important. So, an ear flush under general anaesthetic, often most of these pseudomonas cases would benefit from that.
But as we said before, no rush. So once you've diagnosed it, pre-treat with your steroids, then have them in and flush with saline. And I think you do have to be careful that we don't over clean these dogs ears.
So we certainly do see a subset of dogs where they've had eardrops. Or ear cleaner, very, very regularly, daily, twice daily for long periods of time. And then we do cytology from the ears and all we can see is inflammatory cells in their organisms, and it's because they're having a contact reaction to the cleaner.
So, With the exception of using Tri CDTA to pre-treat. In the early stages of getting rid of the pseudomonas, generally, cleaning would be twice, twice weekly and not more than that in most of my cases. But you do need to be aware of these contact reactions.
And again, that's another reason why your cytology is so important, because if you're getting lots of neutrophils and no organisms on your cytology, it makes you think, what's going on? And rethink your treatment plan. And then obviously, the other main thing to do is address the primary factor that caused the problem in the first place, because if we don't address the primary factor, such as the allergic skin disease, this dog's gonna keep getting recurrent otitis, and you could be back in that situation with the multi-resistant pseudomonas a few months down the line, which isn't what anybody wants.
So, If they're looking like they're allergic, discuss that early on in the course of treatment. Normally I make sure I get their ears comfortable and then I would probably start a diet trial while I continue to treat their ears, and obviously treat any other skin infection that might be present at the same time. I think there's a lot of problems when we deal with these chronic otitis cases and especially Pseudomonas, and one of them is managing the owner's expectations.
I think it's really useful if you can tell the client when you first see the dog, this is going to take us a long time. This is going to take us 6 to 8 weeks probably to get this infection under control and to discuss with them. We've got two things to do.
One is to get rid of the infection, and then the other thing is to find out why it happened in the first place. So, and I think if you talk about that early on, then that helps manage their expectations of what's likely to happen. Owner compliance can be a really big issue.
As we said, putting eardrops in dogs is not easy. I often get my clients to use syringes because then I know that they're using the correct amount of air cleaner and the correct amount of eardrop. And owners seem to like that, and the dogs seem to prefer it.
I think with a lot of the bottles. Clients can end up thinking they've put eardrop in, but actually squirt a lot of air down the ear, which just irritates the dog. So, I think it's worth bearing in mind the use of syringes.
And then also think about ear coaching. So, unfortunately, some of these patients can be very ear phobic, and very scared of having their ears touched because they've suffered with ear infections and it's painful and they're worried it's gonna hurt. So there is behavioural training.
That we can do to try and address that, which works very, very well. So consult a behaviourist if you think that's an issue for you. And then what we really want to do is prevent the infection from relapsing.
So follow up is vital. So we always want to treat past resolution of the infection, and then we probably keep going with cleaners for a long period of time. So the natural cleaning mechanism of the ear, when there's been a severe infection, can be very severely disrupted and can take a long time for that to Start working again.
So we help the dogs out by continuing regular air cleaning once or twice weekly. And then gradually you might be able to back off on that, but some dogs, regular air cleaning is needed indefinitely. So I don't know if you're gonna be able to see these videos, but, this is our behaviourist dog, and she's very fearful of eardrops.
So when the behaviourist first, just to show you the benefits of ear coaching, she goes towards her with some eardrops, and the dog's really not sure and goes and hides under the desk. Because she's really worried about it. But after 4 weeks of behaviour training.
She then, the behaviourist goes, come here for your eardrops. And the dog's much happier to go to her mum with the eardrops. And she's just training with a syringe there.
And that's how we worked at Langford with a lot with the behaviour team and, dogs with recurrent Otis or ear phobias. And it worked really well. We see some really good improvements from dogs that needed to be muzzled that would just come in and lay down and present their ear for examination.
So ear coaching is definitely something to consider. So just to sort of coming towards the end, how long do we need to treat these cases for? That's a really difficult question because it depends how long the infections there.
But generally, we would treat these cases probably for 6 to 8 weeks to get rid of their pseudomonas, and that would include treating sort of a week past. When the cytology was clear, and then we would stop treatment and then we would see them a week after they'd had no drops and were just on cleaner. And I would routinely see these cases back every couple of weeks just to assess their progress.
And especially when you stop treatment. So normally we'd see them have a clear cytology, continue drop for a week, stop, and then see them a week after, just so that we can make sure that it hadn't relapsed, because it's much easier to get things under control if they relapse. Early on than the owner waiting 6 or 8 weeks to bring it, bring the dog back.
So just to summarise, so these cases are really challenging, and they're challenging for many reasons. I think owner compliance is a big part of that and dog compliance, you know, ear earache's painful, and we expect a lot of them and it always amazes me how well. Dogs tolerate having bad ears, so I don't think we'd be as patient.
But consider that they might have otitis media as a complication if cases aren't responding as you would think, and consider early referral if needed. So this little dog here. This pointer ended up having pinectomy and bilateral tiers and pinectomy, because the disease was so chronic, the pinny was probably 1 inch and a half thick on both sides.
So she had one side done there and then she had to have the other side done. We want to try and avoid that if we can. So we do need to treat these cases quite aggressively.
So if you've got any questions, I'll try and answer them. OK, brilliant, thank you very much, Natalie. That was a really, really good talk and thank you again for bearing with us during those technical.
We do have a couple of questions so far, but I'd just like to remind the viewers to hover over the bottom of the screen and type your answer in the Q&A box so that it comes through to me and I'll ask Natalie. OK, so first of all, if you do see neurological signs after commencing topical ear treatment, is it usually self resolving once treatment is withdrawn, and if not, then is there any treatment that aids resolution? So if one of my cases, it's never happened to me in 15 years, but if one of my cases developed neurological signs, I've seen dogs that have been presented to us because they've developed neurological signs.
Generally, we would flush with saline, so we anaesthetize the dog, flush with saline to flush as much of that medication out as possible, which is often why when we're using things off licence, we're trying to use water-based products because they flush out a lot easier than some of the other products, give some anti-inflammatory, continue with the anti-inflammatory doses of steroids, and the, the, the two dogs I've seen were both fine within 48 hours. So, I'm sure that's not always going to be the case, but I think trying to flush as much of this stuff out as possible, with saline and then, managing them. That way.
Lovely. And do you ever put Berylmarvafloxacin injectable intraoral or do you always use water for injection? I always mix it with water for injection and use the tris separately.
It's supposed to be used half, you know, if you read all the texts and the literature, they recommend you using as a pre-treatment. So I guess my worry is if I mix it with PHA tris or, I don't know what that does to the antibiotic. So, that's why I always use them separately.
OK, and would you add in dexamethasone into the homemade topical ear treatment and how much? So generally, generally, I don't. I know a lot of dermatologists do.
I don't because most of my patients are on oral prednisolone. So generally, I, I don't. And as soon as the eardrum has healed, I'll switch the patient onto a conventional treatment, which has got steroid in.
So, but you can sometimes at the time of flush if the ear is very inflamed, and I will put a small amount like 0.1,2 of dexamethasone down the ear. But I generally, personally, I don't add it to the antibiotic mixes.
OK. And do you find Positex OK for Pseudomonas? Orbifloxacin is never included in sensitivity at our lab.
Yes, so, it can work really well for some cases. I tend to, reserve that for the really difficult cases, but I have had a couple of cases that have resolved on it. So if that's what you've got in your practise, that's your floor quiin alone, there's no reason not to use it.
Lovely, thank you. And would you use the same treatment for Proteus infection? Oh, good question.
Probably yes, I would use similar pros normally a bit more wimpy than Pseudomonas, so it's normally a bit easier to, to kill, but yes, the same spectrum of drops would, would work. Lovely, brilliant. And what volume of medical medicated drops do you use?
Horizon, I have used two good squirts. What volumes if using a syringe of Horizontal posts? OK.
It depends on the size of the dog. So half to 1 mL, depending on the size of the dog would be my standard. Dosing.
OK, lovely. And the next one, do you have any comments about using NAC or NAC with Tri EDTA for pre-treating prior to antibiotic topically? No, the NScetylcysteine, I haven't got any clinical experience of using it.
I know some of the dermatologists are playing with it, but I think it's still unclear how much difference that makes, and there's certainly a product in Europe that I don't think it's available in the UK yet that does have an acetylcysteine in it. So I think the jury's out as to how beneficial it is, but some people certainly are using it, but I haven't got any personal experience of it. Perfect.
And thank you for your presentation. This one's from Jonah. You talk about treating pseudomonas for several weeks.
Do you then take breaks using the ear medication as often it's recommended use for 10 to 14 days, or do you just prolong the duration of treatment? I'm following the case with cytology, so I just prolong the, the length of treatment, which is going off licence, but I think it's very unusual to resolve a pseudomonas in 10 days, in my experience. OK, and what volume of your Beryl or Beryl injection to water do you use per treatment?
So I'd make up a, a bottle of in a 14 ratio, so for every 1 mL of Beryl, 4 mLs of water for injection, and then I'd get the client, so I'd make them up a bottle of like 60 mL, so 12 mLs of injectable 48 mLs of water for injection, and then again, depending on the size of the dog, half to 1 mL twice a day. In the air. Lovely.
And you mentioned that air cleaners themselves may be irritant. Is there any which are pH neutral and less irritant for general cleaning? Yeah, so there's quite a lot.
I mean, there's so many cleaners on the market, it's difficult to say, but there are some that are pH neutral, so I tend to use a lot of Surasols, or my petliotic, epiotic is pH neutral. So there's, there's lots out there. So look at what you've got on your shelf and then pick the pH neutral one for longer term cleaning.
Lovely, and we just have a couple more. So I have 2 cases of labs, about 8 year old, first time OE, both with cultured pseudomonas. I have blood tested and negative for hypothyroidism, open mouth X-rays, NAD.
Any hints on the likely underlying cause in such old dog. It's, it's unusual. It may still go on.
We certainly have had a few labs that we've tested at first presentation and they haven't had hypothyroidism, but they've gone on to develop it. So, also because of the breed, you can't exclude allergic skin disease, even if it's just presenting in ears and food allergy can start in older labs. So it's certainly something to think about might be worth like trialling those dogs, checking they've not got any other clinical signs, but we do see food allergies and AP.
That just affects ears in dogs. But if it's a one, if it's their first episode, I'd probably treat that. And then see if it, if it relapses and then if it's a relapsing condition, probably think about going down that route.
Fab. And would you choose to use the Berel sterile water combination over the Marbiel product that's available and ready made for ears or is on? If there's an eardrum, then I would use that.
If there's not an eardrum, I would rather use the, the homemade water-based injectable, especially after flushing. So I think if you think about it logically, when we apply eardrops to an earful of pus, they probably don't go that far down the ear. But once we've removed all that pus, anything we put in the ear, if the eardrums ruptured, is going to go into the middle ear.
So if I know the eardrums ruptured after flushing, I will generally always prefer to use a homemade solution. OK. And do you use any drops chronically to try and prevent any reoccurrence?
So generally, no. I don't use things chronically except when we've got, if it's an allergic dog that gets recurrent allergic otitiss that predispose is predisposing it to getting the pseudomonas, then I do use Resicort twice weekly after cleaning, which is a steroid only eardrop, but I don't use long-term antibiotics. No.
OK, and this looks like it's the final question so far. Do you worry about a buildup of eardrop preparation in the middle ear if the tympanic membrane is ruptured? That's it's a, it's a good question.
If I'm using a water-based solution, I don't, . Obviously, as I said, I think if you've got an earful of puss, how much of that gets into the middle ear is difficult to say, when you're using the commercial preparations that are available. It's not something that I worry about or that I see.
I mean we do see some compact reactions with some topical products that have been used for prolonged period of time off licence. So that is something that we do see. But I don't really worry about build up of products.
I know that if I've flushed in and I've got a ruptured eardrum. And I'm using a water-based product, so hopefully that won't cause a buildup. Brilliant, and we do actually have a couple more that have came through.
For primary infections, do you ask clients to use a syringe, so getting the appropriate dose of eardrops, would that help with client compliance or effectiveness of treatment? I think using syringes, even for air cleaner makes a massive difference to owner compliance. The clients like it and the dogs are much more, much happier, being approached with a 2 mil syringe than they are with a big bottle of air cleaner or drop that might squirt air in their canal.
So it definitely improves compliance. I always give it cleaners with syringes. I, I never give them with just the bottle.
OK, lovely. And Zoe's just asking, can you please repeat the name of the steroid-only eardrops? Resy Court.
It's R E C I C O R T. Perfect. And that seems to be the end of the questions.
So I'd like to thank all of our listeners for staying put during our technical issues as well. I do apologise for that. Thank you very much to everybody for listening.
I hope you can attend a couple more webinars on virtual congress and thank you very much, Natalie, for your patience and your time and hope you enjoy the rest of your evening.