Hi, thanks, Vicky. I'd just like to repeat what Holly said, really, and just thank everyone for getting up so early on a Saturday morning to come and listen to us. Thank you very much.
So, yeah, as Vicky said, I'm talking about anaesthetizing the brachycephalic patient, and definitely in my nursing career, these, these patients have become far more popular as pets now. And I feel that, you know, we see them pretty much on a daily basis for some sort of procedure, then obviously requiring a, a general anaesthetic. .
So My agenda for today is we'll just talk about brachycephaly and, and, and what is it? And also what breeds are affected. How do we diagnose it and, and then obviously, what are the risks.
We'll talk about case management and then what to do if things go wrong. Personally, when I'm anaesthetizing a patient, for me, it's really important to understand either the disease process or concurrent disease, what's going on. And, and for me, you know, I, I want to understand.
The brachycephalic patient, I want to understand what Boas is and, and then I feel I've got a better grasp on how to anaesthetize these patients, hopefully, slightly more appropriately. So what is it? Well, basically, it comes from the Greek bracky, literally meaning short encephalic meaning head, which I feel really fits with these breeds.
And then, unfortunately, our, our brachycephalic breeds are, are prone to then suffering with boas, which stands for brachycephalic obstructive airway syndrome. So probably most of you have seen this image, this was flown around social media quite a lot of, you know, it's been on there now for a few years and, and I saw this shared by Cat the vet on Facebook. I just think it's a, a really nice kind of way of comparing a bulldog to a Labrador.
So obviously you can see the numbers on the diagrams there. So evidently, our brachycephalic breeds have this much, much shorter muzzle. However, they have the same amount of internal soft tissue and, and this is a contributor to then why they have so much difficulty breathing.
They also have a lot of excessive facial skin that's obviously very visible for us when we, when we look at that patient. However, they have the same amount of skin as a Labrador. It's just over a much, much smaller area and hence then you get all of these folds, and then they're really prone to skin infections, which can be really, really painful for these poor creatures.
They also then get this really deformed jaw, however, it often contains the same amount of teeth predisposing them to things like dental disease and sometimes even difficulty chewing their food. 4 to 5 is then just showing you the hyperplastic trachea. So it's often very, very stenosed and malformed.
You can see the difference in, in the size of the trachea and the Labrador versus the bulldog. And again, this is another contributor to why, why these patients have this difficulty with breathing. So what are the primary issues of boas?
Well, firstly, these patients have stenotic nerves, so they have these very, very thin, narrow nostrils. Now this will dramatically increase the resistance to air flow through the nostrils. Now, when I go and have a look at a patient, and a brachycephalic patient that I'm gonna be anaesthetizing.
As long as it doesn't stress them out. If they ever breathe through their nose and they're not panting or breathing through their mouth, I literally just cup my hand and I place it just a few centimetres in front of their nostrils to try and gauge if there's any airflow coming through them. Now, sometimes you'll feel quite, you know, good patent airflow through those nostrils, and it fills me with a little bit of hope that actually those nostrils are relatively useful.
And sometimes you hardly feel anything at all and then it's a it's a bit like, OK, well, then their nostrils maybe aren't, you know, that useful. So now I'm, I'm really relying on this dog being able to, to breathe through its mouth. And having these really stenotic Mary again is is another increase in resistance to air flow.
So the second thing these guys and suffer with is an elongated soft palate. So I've just put some little red arrows on the diagram, on the picture rather, sorry, on the slide. So the surgeon has just put some clamps on the end of the soft palate and kind of just then pulled it forward towards the opening of the oral cavity.
All of that tissue is completely, you know, it's just excessive. . And having this elongated soft palate that just sits there flop flopping about will partially obstruct airflow into the trachea, and it also increases turbulent air flow within the area of the larynx as well.
So I'm really hoping this video works. So when I play this video, it's just quite a short clip, but this is a French bulldog that I anaesthetized and . You're gonna see that it's soft palate is kind of just flapping, causing a partial obstruction as this patient breathes in and out.
However, what we need to imagine is that actually, I've really improved this dog's airway currently because I've got its mouth as open as wide as it will go. I've pulled its very, very big tongue. As far out as I can get it.
And so I've actually really opened up the back of its mouth. And so if you imagine this soft palate, when this dog's mouth is closed and it's, it's just walking around consciously, it's tongue is probably gonna be, you know, more in the way. It's, it's obviously it's mouth is gonna be, be more shut and more closed.
So you can imagine how difficult it is for this dog to breathe. And sometimes when I come to intubate these patients, their, their palate is so long that even as in this video, I'm using the laryngoscope blade to, I, I fed it along the tongue down to the, to the base of the tongue underneath the epiglottis, and I'm pushing down to to try and flip the epiglottis off the soft palate. Sometimes a soft palate is so long that that just by using your laryngoscope, your soft palette stuck over your your epiglottis.
So in that case, I just grab an ET tube, because that's quite a soft pliable end, and I just use that to, to push the soft palette and unstick it from the epiglottis. So the third thing, as I mentioned in that slide comparing the the Labrador and the, and the bulldog, is that this hyperplastic trachea. So as I said, it's very narrow and malformed, and again, this increases resistance of the airflow down into the lungs.
Now, with all of these primary issues, these patients then over time, go on to develop secondary issues. So the first thing is laryngeal collapse. So unfortunately, this is a gradual and progressive collapsing of the larynx, and it's graded 1 to 3 and 3 is the most severe.
Now, grade 1 laryngeal collapse is when the laryngeal saccules become averted. So this is basically tissue that sits in front of the vocal cords and that gets pulled into the trachea. Now, the picture on the right hand side of the slides, this is grade one.
So I've just put a little arrow to these tiny little bits of tissue just sat at the at the bottom. Now, I always remember working with a surgeon who described them as two bold men having an argument, which I think is quite a good, a good way of describing them. So that's grade 1.
Now, the picture on the bottom, just over towards the left, this is getting nearer to grade 3. So actually there's, you know, the trick, the there's now complete collapse of the larynx and, and these guys are, are very, very tricky to intubate. So the second thing they can then go on to develop is tonsilar hypertrophy and aversion.
So the increase in the negative pressure causes the tonsils to become enlarged over time and then they start to protrude into the airway. So again, I've just got a little arrow on the diagram just pointing to the, to the enlarged tonsil. Again, I've got this dog's mouth wide open.
I've got his tongue pulled out. I've got a laryngoscope in there. So I've, I've made this space kind of bigger.
But if you imagine this dog with its mouth closed, actually having two of those enlarged tonsils, they're just getting in the way and, you know, just adding to the, to the problems that these dogs suffer with. So the third thing they can get is pharyngeal muscle hypertrophy, and you just get enlargement of these muscles due to the changes in airway pressures. And again, this can contribute to partial airway obstruction.
Unfortunately, however, I can't really show this on an image. So who's affected? So the list of brachycephalic dogs is, is actually relatively big.
And I think some of these you may even overlook and maybe not really consider them to be brachycephalic. So for instance, certain Rottweilers, I guess we don't see many kind of corsos, but you know, things like chow chows and things, but actually, the list is, is, is quite big. You'll see that I've put in bold, the English bulldog, the French bulldog and the pug, and the reason I've highlighted those is I feel these are probably the most common brachycephalic breeds I definitely see, and I feel that overall of the ones that may be a more affected.
However, I have seen some King Charles Spaniels, cavalier King Charles Spaniels, staffageable terriers that have have also really been affected by boas as well. But what about our cats? So much shorter list, but we've got the British short hair, the exotic short hair, the Persian, etc.
Now you've probably realised already that I actually talk a lot about dogs and hardly ever mention cats. And there's obviously definitely brachycephalic cats out there that we see coming into the hospital and into the clinic. However, I have, in all my nursing career, I've never seen a cat present in respiratory distress because of its boas.
And I think it's just because cats are a lot more sensible. They kind of regulate their exercise. You know, what do they do?
They wake up, they eat, they go outside, might lie in the sunshine, they do a bit of exercise, climb a tree, they'll sleep again, they'll eat again, you know, they're just, they're just a lot more sensible. Whereas you'll get a dog, it will get super excited on a hot day, or want to go outside, chase its ball, and hence, then I think that's when we start to see problems and then these dogs are coming into the, into the hospital in a bit of bother. So I will throughout the rest of my talk, mainly talk about dogs.
However, my considerations that I have for brachycephalics are both for cats and dogs. So obviously these can be put between both species, but I will now talk, you know, mainly talk about dogs. So, how do we diagnose it?
Well, obviously, we can look at the breed. Is it a brachycephalic breed or not? Also, we can then look at the length of their muzzle.
Is it particularly short? Do they practically have no face at all? Or actually is their muzzle a bit longer than maybe we expect it to be?
Do they have evidence of this excessive facial skin? Also, you know, do they have evidence of increased respiratory efforts and also increased respiratory noise. Now these patients can suffer with strider and or surta.
Now strider is a high pitched kind of wheezing sound, and this is caused by disruption of air flow within the larynx and or the trachea, and stirta. This is snoring or gasping sounds that they sometimes make, and this is caused by vibrations within the pharyngeal tissues likely to be the soft palate, the nasopharynx or the oral pharyngeal area. Also then when you auscultate these patients and you listen to their, to their lung fields, that they have referred up a respiratory tract noise and auscultation.
The other thing I also do when I'm anaesthetizing a brachycephalic breed, I don't just auscultate their lung fields. I also put my stethoscope over the the area of the trachea. Now Often when you do that in a brachycephalic breed, you hear a lot of turbulent air flow.
But sometimes in brachycephalic breeds that maybe aren't too badly affected by boas, actually, the air, the airflow is sounds quite linear and doesn't sound that loud. And for me, that's often quite a, quite a good sign. So it's just worth getting into the habit of doing that, perhaps, or at least practising it.
I always look at their nays, are they stenotic? Are they very narrow? And also, as I said, if they, if they tolerate it, I, you know, would just cut my hand and And see whether I can feel any air flow through those nostrils.
Also, is there any history of regurgitation with these patients? Unfortunately, having boas, you're predisposed to having regurgitation. Does the owner report any sleep apnea?
So often brachycephalic breeds, especially ones with severe boas, will really struggle to sleep, and they'll basically obstruct as they're sleeping and wake themselves up and, and they become just very chronically fatigued. Is there any history of collapsing and or cyanosis? We can also think about their weight and their age as well.
So, if brachycephalic breeds is something you're very interested in, it's probably worth going to the Cambridge University website. They're doing a lot of research at the moment into brachycephalic breeds. It's really interesting.
And at the moment, they're finding that fat overweight pugs tend to be a lot more affected. They, they feel with the studies that they've done so far, that the cartilage within the pug's airway is maybe a little softer compared to, for instance, the French bulldog and the English bulldog. And so we all know when we see pugs that are overweight, they tend to put the weight on kind of around their.
Their neck and their shoulders. And so if these pugs are very, very fat, we think it, it may compress the the soft cartilage in the airway maybe slightly more than other brachycephalic breeds. So that's maybe not a a a great sign.
Also, they seem to have found so far that in French bulldogs, if they're very, very underweight, it means probably that their boas is very severe. They regurgitate a lot and then they struggle to put on weight because they just struggle to keep food and water down. Also, as well, it does appear that if, a brachycephalic dog is suffering with quite marked abo us at a very young age, then often their prognosis isn't great, unfortunately.
We can also perform an exercise test as well, because actually, I think it's really important to remember that you could get two identical French bulldogs present to the clinic. They could look exactly the same, you know, then the Marys look the same. They appear to have the same length of muzzle, the same amount of excessive skin.
But actually one can be really severely affected by boas, but the other may be able to run around on a relatively warm day, chase a ball and, and not be affected. So, I think we, we just need to, to bear that in mind. And performing an exercise test, it, it, it, it's always a little bit tricky because you don't want to push these dogs too hard because potentially you'll make them collapse, you'll make them cyanotic, and then you're in a worse state than where you started.
But again, this is something that Cambridge do, so they, they basically exercise these, these dogs for up to 3 minutes, but obviously stop sooner if the dog is not coping. And after 3 minutes of kind of a steady trot, if they're still exercising and they're not really affected by their boas, then hopefully that they're, you know, they're not too badly affected at all. And obviously, then you can determine if you need to stop after 30 seconds, etc.
Then, you know, they evidently have boas and, and it's clinically affecting them. Now, obviously, as only we can really assess the area, then we need to anaesthetize these patients to then be able to have a a good assess of the the extent of that patient's condition. So to be able to look at the size of the tonsils, to look at the soft palate, to see if they've got laryngeal collapse, etc.
So unfortunately, I don't think my sound is working. I'll play this video anyway, but this was a, a very obese, cavalier King Charles Spaniel called Bertie, who I, anaesthetized last year. And this basically, this video, I'm really sorry if you can't hear the sound, but I heard this dog before I saw him.
He had very, very, very loud sturter. And for me, if I can see a, a, a brachycephalic, sorry, if I can hear a brachycephalic dog before I see it, for me, it's not always a great sign. So he's just making this really kind of gasping sound.
Always having to breathe through his mouth, he didn't have any airflow through his nostrils at all, and I literally heard him before I'd even entered the ward, so I kind of knew what was coming. So a few years ago, a survey was carried out by the Royal Veterinary College, and amazingly it found out that a staggering 58% of brachycephalic breed owners did not recognise the signs that their dog was struggling to breathe. And for me, that's amazing and and quite concerning.
So, I think we need to be really, really careful when we take history from these owners, because actually, if they, if they're just oblivious to the, to the patients struggling to breathe, they may give us a history that actually their, their, their dog is completely normal. And evidently that, that may actually not be the case. Now, this clip is of a pug that is silently refluxing.
So what I mean by silently refluxing is that they're reflexing, but they don't actually produce anything. And again, I think this is where we need to be really cautious with history taken with owners is because again, if They don't perceive this to be a problem, and they think it's just normal for the dog to sit and kind of lick the air or gulp excessively. They, they will never report it to us.
But this is, this is what silent reflux looks like. So as I said, it's kind of this excessive gulping, swallowing, this licking the air. Now, obviously, if, if a dog reflexes and produces material, that's obviously very obvious to the owners and, and hopefully then they report that to us, but this is, I think is a lot more subtle.
So yeah, just be really cautious when you're talking to owners about these breeds. So what are the risks? Obviously, right at the top of my list is gonna be that airway.
Now, if possible, before we go on an anaesthetize this patient, I want to try and pre-oxygenate them if possible. You know, some people will say one minute of oxygenation will allow you one minute of faff time. Now, when you pre-oxygenate a patient, ideally, that should be done with a, a tight fitted mask, because kind of just wafting oxygen in front of their, in front of their face doesn't really make a, make a massive difference.
I find, however, that most brachycephalic dogs will not tolerate me ramming a tight fitting mask on their face. So I often don't find pre-oxygenating these, these, these dogs. Often, often works and actually by pre-oxygenating them and making them immensely stressed, it it it's detrimental.
So give it a go, but if the patient starts to become stressed then just stop. Now, with regards to premedication, I never ever leave that patient unattended when it's received its pre-med. And actually, sometimes if they don't tolerate pre-oxygenation, we can post oxygenate.
So post oxygenation is when you start giving them oxygen via a mask, when they've been premedicated, they're a little calmer and hopefully more tolerant. Now, with most premedicants, you'll get loss of normal muscle tone, obviously leading to muscle relaxation, and this can then contribute to this patient's respiratory obstructions. That's why it's really important that these patients are never ever left unattended.
And to be honest, when I pre-med my patient, I tend to have my vet there with me because obviously I, I work, under the direct supervision of a veterinary surgeon, but I literally have everything ready to go. We give the pre-med and then we pretty much start induction straight away. So with induction, we aim for this to be very rapid and smooth.
We find that a deeper plane of anaesthesia tends to aid an easier intubation. Now, sometimes people think actually having these dog, you know, these dogs that are lighter plane of anaesthesia. Surely that makes your intubation easier, you know, that they're able to help maintain their own airway.
But actually, I think it makes it a lot more difficult because you have this dog fighting your laryngoscope. You have them fighting trying to get the ET tube down into their trachea. So I find actually a deeper plane when there's no resistance, there's no coughing and gagging and wretching.
I find it makes it much, much easier, much quicker and much smoother. I also keep the head raised, and when they'll tolerate it, the neck extended and the tongue pulled out, very much like this image here. And having them in this position really helps to open up the airways and, and can try and rectify any, any respiratory obstruction that may occur during premedication and, and hence in the time of induction as well.
So intubation. Obviously, this can be really difficult. So we have a few reasons why this can be hard.
So we have this excessive facial skin and the pug at the top at top right. This is an extreme lot of excessive facial skin. I mean, the dog can barely see because of the, the, the rolls of skin coming off its forehead.
And this facial skin can just simply get in the way. They also often have these very bulgy eyes, and these are very prone to ulcers and trauma. They have this abnormal dent and I wish I could say that word, abnormal teeth.
And so it can make it very difficult to secure that ET tube into place. Having all this excessive soft tissues inside the oral cavity and down around the airway just makes visualisation sometimes very, very difficult and hence intubation very, very difficult. They then have this narrow trachea, and so you you need often a very small ET tube in in relationship to their body size.
And these dogs are always at risk of regurgitation as well. So I always keep the head elevated from the moment I pre-med this patient, I don't let their head fall. I always keep it up, just in case they regurge.
I want to think about the fit of my ET tube. Again, I think this is a little bit, down to personal preference and personal opinion. In my mind, I often will always use a cuDT tube in these guys because of the risk of regurgitation.
So I want to protect the railway. And so actually, for me, with regards to ramming a big ET tube down these guys, there's, there's no price for size. As long as you've got a cuffed ET tube and you can get a good sale of that airway, I think sometimes if you try and ram the biggest ET tube down, you can, you're potentially actually, when you extubate that patient, then gonna be suffering with tissue swelling and inflammation, which then will contribute to their boas and, and make it worse.
So, you know, sometimes I'll just drop down a size, a size smaller than I, I think to try and just be really gentle with those tissues and, and not make the situation worse. Now, I blindly inflate the ET tube, so get them intubated. I then just put in some air into the, into the cuff of the ET tube and make the little pilot balloon taut.
And the reason I do that is in case they regurgitate or, or produce any on any regurgitant material as the head is lowered, ready for me to then kind of get that ET tube tied in and connected up to, to oxygen. I want to protect my airway from the moment that I get it. I really, really don't want these patients to regurg and then hence get aspiration pneumonia.
I'm always prepared as well, so I have suction on standby. I have a very pessimistic selection of ET tubes. I always have smaller than I think I'm gonna need, and I sometimes have a urinary, a stiff dog urinary catheter as well.
And I'll show you it on an image in a moment what I can use that for. We also have a difficult airway box as well, so I always have that nearby. And I, I want my intubation to be as rapid as possible.
It's not something that I'm just gonna stroll off and answer the phone and then come back. I, I want to get this dog's airway secured. So obviously with regards to recovery and an airway, I want to extubate this patient as late as possible.
I want to think about using agents and drugs that are probably short acting or maybe that I can antagonise or reverse. I never ever leave these patients until their head is up, they're able to maintain sternal and then normothermic. I also then just partially deflate the ET tube cuff just prior to extubating them.
And I'll go on and explain why I do this in the next little section of the talk. I'm also very, very cautious with their temperature, so I definitely don't want these guys to get cold, but I also really, really don't want to risk overheating them. I don't want these dogs to wake up and then feel they have to pant because they're hot, because again, that's really not gonna help from an airway point of view.
So I personally try and keep them around 37 degrees if I can, if I can help it. And always, always, I'm prepared to reintubate these patients because it's always sod's law, you don't have anything ready to go into respiratory. Distress or arrest, and you need to reintubate them very quickly.
So I have a slightly smaller ET tube than the one I've just placed, because again, I may have caused a bit of inflammation and swelling and so may not be able to get down the same size ET tube as I, as I did at the start. I, you know, have induction agent. I let my supervisor and anaesthetist know that I'm getting ready for recovery.
So if I call them urgently, they know they need to come and reinduce that patient for me so I can reintubate it. I have tie, I'm near oxygen, etc. You can see the bulldog in the picture as well.
This dog's got its head up. However, it's tolerating that ET tube in place, so I won't remove it until that dog really starts to resent having that ET tube in. So, this is Sally.
She's an English, an English bulldog who came in for a laparoscopic stay. And this video is just to try and show that she is absolutely wide awake. She's not got her head lifted, but actually just prior to me starting this video, she was lifting her head.
She's got people stroking her, she's looking around the room, she's swallowing, however, she's absolutely loving having that ET tube in. So I'll leave it in for as long as she wants it there. And I actually ended up extubating her when she started to kind of throw her head around and try and spit the tube out.
At that point, I extubated. So when I talk about being prepared, I have a really varied selection of ET tubes, again, often smaller than you think. So the image on the top right, they're kind of, ET tube sizes that I would get out for most pugs and, and French bulldogs, and even some English bulldogs as well.
To put it into context, a few years ago, I had a 30 kg English bulldog. Now, he wasn't fat, he actually had a really, really good body condition score. He was a genuine 30 kg, quite large, English bulldog.
He was a really difficult intubation and I got a 3 cuffed ET tube in that dog just. So that just puts it into perspective sometimes how tinier ET tube is compared to their body size. I also as well, may have a selection of laryngoscope blade lengths, and sometimes, you know, you get one and then it turns out that it's too short and then it's pretty much useless.
So there's no harm in having a few sizes available to hand. Again, if you've got a difficult airway box, I have that on standby. I make sure as well that there are adequate staff available.
So if we run into problems, I'm not just me and a vet on our own, that there are enough people around that we can call for assistance quickly. And again, you know, I have suction on standby. Now the the image at the bottom is a an ET tube with a stiff dog urinary catheter fed through the lumen of the ET tube.
So if you end up faced with a very difficult intubation, perhaps the, the, the dog's got grade 2 or grade 3 laryngeal collapse, you can advance the tip of the urinary catheter just through the larynx, just into the trachea. You then hold that urinary catheter in place and then you can railroad the ET tube off the top of the urinary catheter and that can really help with making that intubation a little bit easier. On the top right image as well, we do have some, silicon spray that you can spray onto the ET tubes.
It just helps to lubricate them and can again aid with your with your intubation and make it a little bit easier. Just one little tip, do not spray the ET tubes with the silicon spray kind of spray in the floor, you will make a colleague slip over and potentially hurt themselves. So try and spray it over the sink or something.
I've definitely learned the hard way. So a difficult airway box, if you don't have one in your practise, I think it's a good idea to just put one together. It doesn't have to be very fancy, just a little B&Q or home-based little toolbox with a few bits in it.
So what should it contain? Well, I've just put a list there, so. We should have some suction catheters.
As I said, some urinary catheters are really helpful. You can put a few three-way taps in there, some swabs, and sometimes it's really hard to grasp the tongues on these patients. They can be quite slimy, full of saliva and stuff.
And also sometimes you need to swab out the back of their oral cavity if there's a lot of mucus and, and, and froth. Some scalpel blades, some tube tie, a laryngoscope with various laryngoscope blade lengths, some in be potentially, various size cuffed and uncuffed ET tubes. You can have various gauge catheters, also a selection of LMAs and LMA is a laryngeal mast airway.
I am personally, I'm not a huge fan of using a laryngeal mast airway and a brachycephalic, because my concern is, one, if they regurgitate, you're not actually protecting the airway, so they still, you know, they're, they're at risk of aspiration. And also if they have any form of laryngeal collapse, you're, you're not getting a patent airway because the laryngeal mask is sitting. Kind of rustral to the, to the, to the problem, if that makes sense.
So I think it's good to have them in the box just in case, but they're not my routine go to in brachycephalics. Have a catography line and connector, think about having a tracheostomy kit, maybe a TP, some suture tape, and a cuff puff. And basically you've got hopefully most things there for difficult intubation and potentially an emergency tracheostomy as well.
So the, the second thing on my consideration list with these dogs is, is regurgitation. So they often will have a hiatal hernia. Now, some of them are are congenital, so they're born with them.
And some of them a little bit dependent on which surgeon you talk to, we wonder whether these dogs may actually acquire hiatal hernias over time. A hiatal hernia is where the cranial portion of the stomach enters the distal oesophagus, and the image on this slide is a fluoroscopy image, and I've just put a little red arrow pointing to the portion of the stomach as it's entering into the distal oesophagus. That's, that's quite a nice example of that.
Now the hiatal hernia is there due to the increase in negative pressure as these patients breathe. And Again, this is a little bit dependent on kind of surgeons, but also some owners do report that they feel the regurgitation in their dog improves after boas surgery. However, we feel that there's, you know, more studies required looking into this.
But, but some owners definitely do say that they, they notice that their dog regurgitates less after it's had airway surgery. These dogs can also have poor esophageal motility. Again, this is due to the increase in negative pressure.
There is a study currently underway to determine if airway surgery does improve the motility of the oesophagus or not. Again, some owners do report improvement in symptoms and some not, so we're still a little bit unsure at the moment. Acid reflux.
So, again, they get acid reflux due to the increase in negative pressure. This can cause esophagitis and also can cause aspiration pneumonia as well, which obviously can be really, really troublesome. And I've said it again and again and again.
I always have suction available or on standby and someone ready to grab it for me quickly if I need it, or I have it all plugged in, ready to go if that's possible. This is just a picture of our suction unit here on the, on the slide. So the other thing I'm really cautious about is any ocular trauma or damage to these patients.
So often their eyes are very, very bulgy and they really protrude. They often have difficulty closing their eyes as well, even when they're asleep, sometimes you look at a brachycephalic patient and it, it can look awake, and it's just simply because their eyes are so bulbous that the, the eyelids just simply don't, don't meet and they don't close. The other issue as well is if you accidentally press on the eyeball, you can cause that patient to suffer with vagal stimulation and, and that could cause a severe bradycardia which can lead to cardiac arrest.
So we just need to be really cautious not to do that by accident. Here at here at my clinic, we lubricate the eyes immediately post induction, just whack loads of lube in there and then we lubricate them regularly throughout the anaesthetic if possible. I'm also really cautious with warming devices, things like bear huggers.
So I try and position the hose to come from the the dog's bum end and not near his face. I just don't really want warm air blowing onto those bulging eyeballs causing the corneas to get a bit upset. Also, if you're holding for intubation yourself or you're intubating and you've obviously got someone holding that patient for you, just really take care about how you're holding them and that you're not accidentally pushing on the eye or, or, or touching, rubbing the cornea.
And again, I think it's just good to pay really close attention when securing the ET tube in. As you know, as I work in a teaching hospital, we work with students a lot, and sometimes you'll see that they've just tied it in in a bit of a panic as they're quite flustered and sometimes the tie can be very, very near their eye or even on the surface of their eye. So I think it's just something to be, to be very cautious of.
So let's talk about case management. So ideally, if possible, I really like an IV catheter to be in place prior to pre-medication. Now, obviously, sometimes this isn't always achievable, and at the end of the day, we have to prioritise our staff's health and safety, and we also have to think about our patient as well.
There's absolutely no point pinning a patient down, especially a brachycephalic one, to try and get an IV in if we're going to cause it to collapse and make its airways worse. So, If, if an IV is, is not possible, obviously, we're gonna have to sedate this patient IM to make IV placement, you know, possible. So, if that's the case, I pre-medicate the IM with either an opioid plus or minus an alpha 2 agonist or ACP.
I have everything ready for a potential rapid induction and intubation. The patient is never left unattended, and I have everything ready on standby to include the difficult airway box as well, just in case. As I said, it's really, really important that we don't stress these patients out.
So if they won't tolerate IV placement, we have to go down the IM route, and it's really important we try and keep these dogs nice and calm. So if they've got an IV in, great. So, pre-med IV for me, my, my choice is gonna be of my opioid is definitely dependent on procedure.
So if it's non-painful, I tend to go for something like borphenol. If it's painful, we've got drugs like methadone, buprenorphine, fentanyl, which is a potent but very short acting analgesic, etc. So immediately pre-induction.
I administer the, the, the pre-med. So, I think sometimes there's there's a, a couple of ways of how you can pre-med these patients, and it depends a little bit on how concerned I am about their airway. If I'm very, very worried about the airway, I may just give them the opioid as their pre-med.
I may then ask my supervisor and anaesthetist to induce them so we can get a nice secured airway, and then I may think about giving them the sedative. However, if I'm not too concerned, I may give that that sedative and the opioid as the pre-med induce, get the airway, and then on to oxygen. So there are a few ways of managing these cases, depending on how concerned you are about them.
So As I said, we've, you know, if you can pre-oxygenate them, great. If not, if the patient becomes stressed, stopped, you know, stop doing it. And then, you know, you can, you can start post oxygenation after you've got that pre-med on board and they're a little bit more relaxed.
I personally, tend to pick alpha 2 agonists for except, you know, example, Dexamedatomidine. For me, it's a shorter acting drug, but I can also antagonise if I run into any problems. ACP is definitely an alternative choice.
However, it's long acting, 6 to 8 hours, and we can't antagonise that. So I think we really need to consider that when we're thinking about our, our pre-med protocol. So induction, I think in most patients, we can either use propofol or faxol alone.
Obviously, this drug is administered to a to effect to allow intubation and sometimes to allow an airway exam if that's required. And obviously that's done by our supervising vet. As I said as well, that a deeper plane of anaesthesia will make your intubation much, much easier.
You don't want these dogs and cats fighting against you to try and get an ET tube in. Now with maintaining anaesthesia, I often will pick Sivaflurane over isoflurane, because it's been shown that Sivaflurane can have a faster recovery, and that's what I really want in these guys. I, I want them up and about as quickly as possible.
I want them to look after their own airway. However, if you've only got isoflurane, I think that's absolutely fine as well. It's, you know, that'll be fine.
But, you know, we've, we're lucky we've got the choice of both, and so I, I tend to go for cedarflurane in my brackycephalic patients. Also as well throughout the anaesthetic period, these guys might require ventilatory assistance. I often find that they don't tolerate being on their back particularly well, you know, that they're quite barrel-chested and often they're they're overweight as well.
So that can, you know, put pressure on the diaphragm. They may not be able to ventilate as well. Sometimes we need to give them IPPV or pop them on a mechanical ventilator.
So recovery. I will often chat to my supervising anaesthetist and will consider whether we antagonise that Dexedatomidine or the alpha 2 agonists that I've used in the pre-med, and that will be a little bit dependent on the patient's temperament, how long the procedure's been, and how concerned I am about their airway. I will leave the patient intubated, as I, as I've said until their head is up, and they're no longer tolerating that ET tube.
I partially deflate the cuff on the ET tube, so take about half of what I've put in. And the reason that I just partially deflate the cuff on the ET tube is if that patient has regurgitated under the anaesthetic, you, you, you may see they've evidently regurged and sometimes they silently reflux and, and so you have no evidence of that. Now, If they have regurgitated, the risk is that some of that fluid has, has gone down the trachea and is now sad, being stopped going into the airways by that cuff on the ET tube, which is obviously part of its purpose.
Now, my concern is that if I deflate that cuff completely, I'm letting any fluid just go straight past down, down into the lungs and then that patient's gonna aspirate it. So the thought process like behind partially deflating the cuff on the ET tube is that hopefully you drag out any fluid or any mucus, etc. With the ET tube as you extubate them, but hopefully leaving their trachea and the larynx obviously in place and not ripping that out with your ET tube.
Now it's really important in recovery that if these patients become stressed, or very anxious and they're fretting, we really need to consider sedating them because it's, it's gonna be in their, in their, in their best interest actually to sedate them, to calm them down because they'll just make the airway worse. So for me, I think the ACP works really well in this particular. Scenario.
So we use often a low dose of 0.01 mg per gig or even lower. So you can use 0.005 mg per gig.
And I find this helps to calm the patient but without over sedating them. And I think it reduces their panic response and it allows the patient to breathe more slowly and more effectively. But it's really, really important that then this patient is very closely monitored.
And we're really lucky in my clinic where we have an ICU. So our BOAS patients go back to ICU and hence, and if they get stressed and they require a bit of sedation, they're monitored 24/7 just in case something goes wrong. I think it's really important as well that we talk to the vet to find out actually, do we think giving non-steroidals is a good idea or not?
Again, this will all be down to a little bit of personal preference. And sometimes again working with different surgeons, they, they have different ways of doing things, which obviously is completely fine. Some surgeons are very happy for me to give a non-steroidal, for instance, meloxicam at the start of the procedure, because they may personally not use steroids if there's a, if there's a problem with the airway.
However, some surgeons asked me to hold off given a non-steroidal, just until they're at the end of the procedure in case there is any airway inflammation or swelling, and, and then they may want to give steroids to try and prevent obstruction on recovery. So I think that's just a discussion that's very, very good to have and just see where, where your opinions lie. So I don't think you're, you're getting any sound, unfortunately.
So I'll, I'll just kind of try and describe what's going on in these videos. This this is Lola. She's a French bulldog, and she's just had an airway surgery.
So she's had her nostrils done, she's had a palate done, she had her tonsils removed and also, her inverted laryngeal saccules removed. So she pretty much had the full works. Her recovery to me was was just textbook, really what I wanted.
So I extubated her late when she stopped tolerating the ET tube. She's able to hold her own head up. She's looking around, but she's very, very calm, very relaxed.
She's taking nice, slow, really effective breaths. So for me, I was really, really chuffed with with Lola's recovery. That to me is textbook and, and kind of perfect.
So this is Sally who was in a, a video previously with her ET tube in wide awake looking around. So this is her after her laparoscopic procedure. She's evidently now recovered, she's very, very bright and happy, you know, she's really interactive.
However, I didn't feel she needed sedating because actually she wasn't being silly, you know, she wasn't stressed. She was just a young dog, quite excited and pleased to see me, but actually she wasn't getting herself into, into any bother. So I found that tolerable and fine, but the ICU staff were keeping a close eye on her in case we did need to intervene.
Now, unfortunately, this is poor Hoch a staffageable terrier. He had his nostrils and his palate resected. His recovery, unfortunately was awful.
When I extubated him, he became very, very, very stressed and anxious. He was howling and whining. And with this degree of vocalisation, he unfortunately then started to make the palate site bleed where he may be kind of dislodged a blood clot.
So then he was spraying blood all over me. So it's a little bit stressful. So Hooch was a prime candidate where I, I went and grabbed my supervisor and anaesthetist.
I said, I'm really not happy. He's very, very stressed. He's very agitated.
He's not really breathing very well because he's just vocalising continuously. So Hooch received a low dose of ACP IV. We popped him in a kennel.
We kept it nice and calm. He was continuously observed and actually the ACP really helped. It took the edge off him.
He calmed down and then he, he went home the next day and was much, much better at home. So this is a video of a French bulldog that I anaesthetized for MRI. This is just to show that that our brachycephalic breeds can obstruct in recovery completely silently.
They don't have to make a big song and a dance about it. It doesn't have to be overly dramatic. They can do it completely silently and then you can turn around and find that they're, they're practically dead in their kennel.
So what I want you to do in this video is to look at the patient's chest. So hopefully here you can appreciate that it's got this paradoxical breathing. So the dog tries to breathe in, it's obstructing, its chest wall is getting sucked in and the abdomen is flaring out.
So what we're gonna do here is just if the dog will tolerate it. I lift the head up, extend the neck to try and help open up its airways, and then hopefully in a second, you'll see that this chest movement becomes much, much better. It's now got, it's got patent air flow through its airways, and then it's, it's breathing pattern is much more normal.
So on inspiration, the chest is, is, is expanding rather than getting sucked in. And then when we drop it down again. The dog then re-obstructs.
So even though this dog's extubated, because actually it stopped tolerating its ET tube, it was flinging its head around, it's now started to obstruct again. And this is why it's really, really important that we don't just extubate these patients and then walk away. So what to do when things go wrong?
I know it's very, very easy to say, but I think it's really important that we just try and stay calm. We all know when we get flustered, we just don't work as well, you know, we, our processes, our thought processes are all over the place. We, we start to faff, we start to drop things, things start to go wrong.
So we just need to remain calm. It's really important that you get help. OK, so you get assistance as quickly as possible and you need to make a judgement call.
And there's absolutely no harm in waking that patient up if it's not an emergency procedure. If you anaesthetize the patient and their airway is far, far worse than you ever anticipated, there is absolutely no harm in antagonising or reversing what drugs you can and allowing that patient to wake up. So then you can actually sit down as a group and discuss actually, OK, this was far worse than we ever anticipated.
We now need to think of a plan. So when we, you know, are faced with this next time, we have steps in place to follow. We kind of have an algorithm of things to follow to hopefully then make that that patient as safe as possible.
So don't ever think waking up and walking away from these patients is a bad thing. So I, I, I don't think it is. I think that should definitely be considered.
We need to think actually, so with that French bulldog in the, in the last video, do we need to reinduce and reintubate this dog? And I think that needs to definitely be thought of. And again, as I've said, if you've got all of that equipment ready on standby, then that that shouldn't be too much of an issue for you to achieve.
And also then we have, you know, do we perform a tracheostomy? Hopefully you, you practise, you know, if you've got a tracheostomy kit ready and sterilised, ready to go. Sometimes I have patients where, you know, we're very, very concerned about their airway, and if they tolerate it, we may preclip them for a tracheostomy, an emergency tracheostomy just in case.
We definitely don't do it with every brachycephalic, but we do it with some. And I think for me sometimes. If you have to perform an emergency tracheostomy.
Do not worry about, about asepsis. You know, don't worry about furiously trying to get this patient clipped and prepped. If your patient is going to die, you somehow need to secure an airway.
And if that means just doing an emergency tracheostomy without clipping and prepping, then that has to be done, OK? And then we can think about the, the, the antibiotics and, and the possible infections afterwards, but Again, I think a tracheostomy definitely should not be taken lightly and I'm not suggesting we just ram tracheostomies in without clipping and prepping these patients, but I, I think, you know, at that time, you have to make a very quick call, obviously your vet does as to, as to what route you take. This is just an algorithm that is used in human hospitals when there's problems with difficult airway.
So just take a few minutes to just have a look through and you'll see basically their steps of, of in humans when we go into hospital, what happens if, if we're difficult to intubate. Humans actually are, we are quite difficult to intubate. We're not a very easy species and often in in most big hospitals is actually someone employed who runs around the hospital with a with a a difficult airway backpack, and then they're called if the anaesthetist is struggling to to intubate that patient, they arrive, they whip open their backpack, and then they're there to help assist with the difficult intubation.
But it might be worth having this algorithm or something similar in your practise. So obviously feel free to take a picture of it. And you can discuss it with your vets and, and see whether it's actually worth having, having one of these available in case you do run into problems with your brachycephalic breeds.
And then hopefully, if anyone's got any questions, please feel free to ask them. Great. Thank you.
And, and that was a really, really interesting talk, and I especially like the sort of videos and photos that we got to, see all the way through. I'll encourage people to type in any questions, but in the meantime, Helen, I've got a question for you. You said about, the vagal stimulation, these dogs are vulnerable to you when you're handling their eye.
If you are doing something like an eye surgery and they have got that bradycardia, is there anything you can do for that? So the first thing, because often with the vagal stimulation, the, the bradycardia is, is, is very rapid and, and often very severe. So I just ask my surgeon to stop.
I just asked them immediately to stop what they're doing. And often if it is a, a, a vagal induced episode, then the, the bradycardia should resolve itself, hopefully. If not, you need to think about giving a drug to speed up the rate, so maybe something like atropine or glycoylate.
Lovely. Thank you, Helen. We've had some questions coming in, and actually, both Zoe and Emma have got very similar questions.
They've asked if our vets, give any antacids before the surgery or post-surgery in these patients. Yeah, so again, I, I find this is, is quite a, a personal preference thing from surgeon to surgeon. We don't give every single brachycephalic kind of things like omeprazole or ranitidine.
We do in some. So I think sometimes if there's evidence that that patient is regurgitating and they're often on antacids already. However, you know, if it's not reported in the history, then maybe they won't be.
Our protocol here is if a patient regurgitates under anaesthesia, we tend to give them a dose of omeprazole. And then obviously it's kind of down to the clinician in charge of that case as to how long then they keep that patient on omeprazole and or other antacids for. So it's not something we do routinely, but it, it, it, you know, it's a bit kind of clinician dependent, I find.
That's lovely, thank you very much, Helen. It looks like those are the, the, oh, we've got one more question. Do you often have to place the IV post pre-med?
And if yes, do you, do you do this after the opioid or do you wait until induction after the sedative has been given? I find actually, probably most of our brachycephalic breeds do have IV catheters in already. However, I am definitely faced with brachycephalic patients that I have to anaesthetize that, that, you know, I have to sedate IM.
So what I tend to do, unfortunately it's very much a, a patient dependent thing and, and it depends kind of what their procedure is, how stressed they are, and also, well, you know, if they're fear aggressive and, and they're very difficult to handle. So it, it's very much a, a patient dependent thing. I tend to in, in most patients, give them an opioid, with a combination of something like Dexedatomidine IM to kind of make them amenable enough to handling to have an IV placed.
But often we will give them a lower dose of Dexedomidine, I am compared to, you know, your Labradors, your colleagues, etc. Because actually, in most cases, I don't really want to profoundly sedate these dogs because of the risk of their airway and regurgitation. But what I want to achieve is just to take the stress away, just to allow them to, you know, have an IV placed without really resisting it.
So that's kind of commonly how I approach them. I hope that answers the question. Yeah, that's great.
Thank you very much, Helen, and thanks again. That was a a lovely talker I'm sure you'll all agree.
