Thanks, everybody, for joining me for this, webinar on boosting confidence in rabbit anaesthesia. Now, I know that there's a little bit of a reputation with bunnies in practise. And I'm not saying that that's not a reputation that they've earned, but hopefully, we'll be able to dispel some myths, have a look at the actual facts, and this presentation should hopefully give you some tools to go away, and put into practise.
A few more things that are going to safeguard our bunnies, pre, during and post anaesthesia. So for a little bit of who the hell is talking to me about rabbit anaesthesia. My name is Tawny, I'm an RVN that graduated in 20.
16, which is, longer ago than I actually, feel like it is. Still feels like 2 minutes. But I, I've worked in referrals for the last, I want to say, 6 years.
Not exotic specific, but my, experience in anaesthesia is, is quite focused and has been, especially over the last 6 years or so. In terms of exotics, I've always, had an interest in exotics. Rabbits in particular, mostly because I really enjoy anaesthesia, and I also really enjoy, sort of the research side of evidence-based nursing, where we're looking at the, OK, well, hang on a minute, how is this patient receiving care differently?
Why do they need to receive care differently? Or even do they need to receive care differently? So, that's a little bit of my, nerdy interest.
So, I, I've completed my, nursing certificate in exotics, nursing certificate in anaesthesia. I've got a master's in Endangered Species recovery and Conservation. And, basically, I'm just a, a giant nerd for anything exotic, anaesthesia related, or generally veterinary nursing.
So, hopefully, I'll be able to answer any questions at the end. But if, for whatever reason, if there's a question that you've thought of that I haven't been able to answer during the presentation, just let me know, either drop me an email. I think my email's at the end.
Or you can drop me a message on Instagram. I'm the veterinary nerd, so yeah, you can, you can always get in contact with me afterwards. So, when my screen decides that she wants to work, there we go.
OK doke. So when we're looking at anaesthetic risk statistics, I prefer to use what is probably the most renowned, study, so the, the most well known study, when we're talking about anaesthetic, per-anesthetic mortality rates. And that's the Broadbelt 2008 study.
So I know that, yes, this was a 2008 study, which was longer ago than any of us would care to admit. But what we're actually looking at here is one of the most extensive, inquiries into perioperative, mor mortality and morbidity rates. So.
That's why I tend to lean on this study. There are more up to-date studies, involving various species, some with cats, some with dogs, some with rabbits, some with an amalgamation of all of them, but none of them have got the, extensive, broad and robust data set, as the Broadbelt 2008 study, because that was such a huge, huge undertaking. And having done.
My own research, I genuinely cannot imagine, going through that amount of raw data, that would make me want to cry. So, given that we know that we're looking at this study with a reasonable, like, confidence interval, we know that this is, a reliable paper. The statistics, dogs and cats, we know.
Are at a slightly, well, they're at a fairly. Reduced per-anesthetic mortality and morbidity rate than rabbits. Now, rabbits, the, so the, the ASA score, I'm hoping that everybody is doing in practise.
So sometimes I say ASA score, sometimes I say ACES score. What I'm actually talking about is, the American Society of Anesthesiologists, which they have sort of, well, they, in humans, would score, 1, I think it's 1 to 6 in humans, but 6 is more like organ donation level, which obviously is not something that we entertain in VettMed, . But what you're basically looking at is, the lower the score, in theory, the lower the perian anaesthetic death risk.
And the higher the score in theory, the higher the per-esthetic death risk. So, when I'm talking ACES score 1 to 2, I'm talking your routine procedures, like, it's a cat cast rate that's come in with no other history. Or I'm talking, you've got, I don't know, a dog that's come in for a dental, and it's got nothing other than dental disease and a little bit of, I don't know, gingivitis or something, very mild disease that isn't actually, causing a bother.
Anything that is 3 and above, that's where you're looking at things that have got, significant disease, but they're compensating, significant disease and they're not compensating, or like an ASA 5 would be something that this patient's gonna die, whether we anaesthetize them or not, or is at risk of death if we anaesthetize them or not. So, I'm talking sort of gastric torsions, anything that's, I don't know, heme abdomen or anything like that, lung lobe torsions, things like that. So, with rabbits, ASAs 1 to 2.
Statistically, as per this 2008 study, we're looking at 1 in 137, so that's one patient in 137 would experience a perianesthetic morbidity or mortality event. Once we get to ASA 3 and above, you're drastically, drastically changing that. You're looking at 1 in 14.
So we're looking at 0.73% will die, or, or at risk of death in the first two categories, but 3 and above, you've times that by 10. Like, that is such.
And you would also assume that that is exponential growth, so you would assume that if you were to survey this on every single rabbit that's ever had an anaesthetic from this 2008 study. Until today, you would assume that there's exponential growth there, but. Will, will go into it.
Dogs, again, dogs have got such a, a drastic, difference in how many we anaesthetizes per year. And the same with cats. And so sometimes those figures might look a little bit more diluted.
But once we get to ACE score 3 and above for dogs and cats, we're looking at very similar figures. So 1.3%, 1.4%.
You're looking at similar figures. I will say that for me, one of the most important things, despite the fact that this study is obviously extremely robust in its methodology and its data set, one of the most important things for me is the fact that this was, and I know that you're all gonna hate me for saying it, but this was almost 20 years ago. And I would like to think, I know that 20 years ago was obviously the 1980s.
I know that, you know that. But it wasn't. It was, it was actually, it was 2005.
But anyway. I think the way that we approached exotics and veterinary medicine in general, 20 years ago, is different to how we approach exotics and veterinary medicine now. That's not me saying that it was wrong then, but what I'm saying is that we have got more information.
We have developed, our methodologies. We have worked on the experience of the last 20 years, and that has presented us with where we are now. So, I would like to think that if we were to carry out this study again in exactly the same hospitals, exactly the same way, etc.
Etc. I would like to think that maybe the dog and cat figures haven't changed particularly much, but I would like to think that the rabbit ones would have. Mostly because I think in 2005, we were probably, the vast majority of people were probably still scruffing cats and thinking that that wasn't a stressful thing to do for them.
So there's quite a lot of, changes that we probably take for granted. Because we just haven't thought about it for a while. And actually, those sorts of changes, are what are potentially reducing the stress in our patients that's then gonna save their life because they don't already have this windup of stress before we anaesthetize them.
So These guys are a prey species, so unlike our, predators are dogs and cats, we have got prey species, so they function a little bit differently. Those of you that, also work in farm will understand that that makes a bit of a difference in how things, react to you, and it's not. It's not to say that you won't get some extremely bolshy rabbits.
It's not to say that they're not, triggered in the same fight or flight response or freeze, as other species, but just, they have different requirements. So as prey species, they are naturally wired to assume that everything is here to eat them. And that includes us.
Oh, sorry. That includes us. They assume that, we're gonna hurt them, we're gonna kill them, whatever.
And obviously, we're not. But it takes a certain level of trust. So everything with these guys is wired to, don't die.
And I know that everybody, myself included, at some point has probably said or participated in a conversation where somebody has said that rabbits just like to die. These guys are actually They're, all right, they're not quite as evolutionarily advanced as, I don't know, a cockroach or a crocodile or a crab. Like, they're not as robust as that, but they are designed to stay alive until they absolutely physically can't anymore.
They will, they will make it through. These guys are underdogs, so as much as they might look soft and cute and fluffy on the outside. And you think, oh yeah, they're just a bit pathetic.
They just sort of, they get a bit of a tummy ache and then they die. No, what actually happens is they are so fantastic at compensating and compensating and compensating that you won't see anything on the outside until it's too late. So they do have different requirements to cats and dogs.
One of those main differences is that unlike cats and dogs where they go into shock, and they can potentially end up with some kind of gastrointestinal upset, or. Any, any kind of, oh I, I'm a bit nervous, I think I might just nip the toilet kind of reaction. Rabbits don't have that.
Rabbits have, effectively their lungs will just fill with fluid. So they're sort of shock organ, if you like. Is their lungs, and that can lead to right side of heart failure in the face of extreme stress.
So when I say extreme stress for us, that would probably be a very different situation to a rabbit experiencing extreme stress. So a rabbit experiencing extreme stress might be. That they've been sat in the waiting room, where there's a Rottweiler barking, there's a kid running around in circles.
Everything's really noisy. They've been put on the consult table. They've been tipped out of their box because they were too frightened to come out.
They've tried to jump off the table because they genuinely thought they were gonna die. Then they've been grabbed because they almost jumped off the table and they were stopped. And then they've been tipped upside down in order to be examined.
And worst of all, somebody's taken their temperature. So, obviously, that all of that, it might be. Just a rabbit consult to us, but that's an extremely stressful stimulus for them.
So, what's gonna happen in the face of this stressful stimulus is they're obviously gonna secrete catecholamines. So adrenaline's gonna be secreted. That will increase the heart rate.
That means that, I mean, these guys already have a high heart rate. But that means that Eventually, you are going to get a decrease in cardiac output. Because cardiac output is your heart rate times by your stroke volume.
And if your heart rate keeps going up and up and up and up and up, your ventricular fill time is being reduced. So that means that your stroke volume is being reduced. Now, the only way that the body can compensate for that if you are producing less of something.
Is to do the same rate, so you pretend that you can't increase the amount of what you're producing. So we can't improve that ventricular fill time to kick out more blood per contraction. The only way that the body is going to be able to compensate for that is by increasing the heart rate again.
But that then, again, reduces your ventricular fill time, reduces your stroke volume, and it's just a perpetual cycle. Until eventually, you're basically struggling to oxygenate the important bits of your body. And you end up with a myocardial ischemic event and probable cardiac arrest.
So, that is how something that to us doesn't seem that stressful. But to a rabbit that probably already lives with a, a level of chronic stress, which I'll talk about later. This is how it ends up with, oh well, it just came in for a claw clip and then it screamed and died on the table.
So this is how, this, this sort of cycle of stress works and how it can impact these guys, and much like. We would say, in a, in a dog that, I don't know, was, was growling and, progressed to crocodile rolling, we would say, yes, that is, that dog is stressed. Equally, a cat that you've managed to successfully burrito, but then she starts open mouth breathing, we can recognise that stress.
But in a rabbit, aside from the fact that they already have a high respiratory rate and a high heart rate, and they're already a bit flighty as a species anyway. At what point are we saying, no, this rabbit is stressed. It's incredibly, incredibly difficult.
And so for me, I, I can't foresee a situation where a rabbit would be completely stress free in a veterinary practise, so there's no reason not to treat them as if they are stressed. And so for that reason, I want you to have a think about how these guys are being processed through your hospital. And I know that some of you have probably sat there thinking, I'm sure she said this was an anaesthesia talk.
It is. I promise you it is. But the art of this is not the, the art of.
Anaesthesia, particularly in exotics, is that we are making sure that they are well catered for, is in as close to their normal, like, homeostatic and husbandry requirements as possible. So that then we are not altering that sort of normal range too much. We want to keep everything as normal as we can.
Because once we start pushing them to extremes, that's then when we start to put their body in trouble, and that's then when we have per-anesthetic mortality. So, where are they in the waiting room? Do you have a specific exotic section?
Do you send the rabbits to the cat side because it's quieter? Do you, not have enough room? And so they're in with all the rest of the rabble, and you've got two dogs barking at each other, or two little cockapoos bouncing up and down, and this, poor lady with a rabbit sat under the chair between them.
And the rabbit's fearing for its life because it doesn't understand what's going on. So, if you've got a separate exotic section, amazing. It, obviously, if you've got, I don't know, a rabbit coming in and somebody is bringing a ferret in, maybe just have a think about the fact that that ferret will definitely be able to smell that rabbit.
And that ferret's actually probably gonna chill out because you're gonna think, Oh, this is amazing. That's really interesting. I'd like one of those.
OK, cool. But the rabbit is gonna walk in and immediately panic because it's basically just been sat in a room with it's one of its biggest predators. And it knows that.
So. In terms of where they are in the waiting room, if you can keep them completely separate from anything that is potentially gonna eat them in the wild, because we know that they're not as domesticated as cats and dogs, then, ideally, we'll do that. If that means that they have to wait with the client in the car or in the car park, then that's fine.
But just have a think about where they are in the waiting room. Where are we housing them? So I absolutely, it drives me up the wall to, if I, if I'm on a locum shift and I come in and they, they find out that I, I like exotics, I'm like, yep, no problem, I'll have the rabbit.
And it drives me absolutely insane to then find out that the rabbit's been put in an upstairs kennel. And I know that for some, there isn't really any other option. Maybe you've, like, you've only got one ward or whatever, but what we should be doing is housing these guys, preferably away from everyone else, in as quiet a space as possible, and in a downstairs kennel, so a bottom kennel.
These guys spend their entire life no more than a few inches above the ground. They spend their entire life on the floor. So, unlike Daxis who, when they spend their entire life on the ground and then you pick them up and they think they're king of the world, and they start, like, having a, having a look at stuff and they actually stop kicking off, rabbits are the opposite.
They're gonna find it extremely stressful. If somebody, so if you didn't feel well and you. Went to the hospital and they were like, Yeah, no problem.
We'll get you hospitalised. We'll make you feel better. And you're already a little bit white coat, you're already a little bit frightened of doctors, and you were already a bit nervous.
They're like, Yeah, no problem. We'll get you sorted out. We'll get you on some medication.
The bed that we've put you in is on the roof. Obviously, you would have a little bit of a, a, what? And you wouldn't be able to relax because that, why would you want to be on the roof?
You don't want to be on the roof. You wanna be in somewhere that is normal to you. So think about where you're housing them.
Following on from that, where are we handling them? So I again will do my absolute. Utmost to not handle rabbits on the table, because one, it's stressful for them.
I don't want to be hospitalised on the roof, I also don't want my clinical exam doing on the roof of the hospital. So if we can do it at a normal level, that's absolutely fine by me. So I don't want my rabbits to be on the top of the skyscraper in their heads.
I want them to be. At and what is an, an acceptable stress level, not a normal stress level, but an acceptable stress level for them. So where I'm handling them, I'm gonna do that on the floor, even if the client comes in and puts the box on the counter.
I will have already, before I've called the rabbit in, put a towel on the floor, and whether they listen whether the client listens or not is obviously different. But I will tell the client, just pop the box on the floor and open the door, and we'll see if he wants to come out. And that's my plan.
And then whilst I'm getting a background and a history from the client, that's then when. Hopefully, the rabbit will be interested and, and come out. But failing that, it's given him a minute to sort of adjust to his new surroundings.
So, the other reason I'm handling them on the, on the floor is because when they're on the table, if they decide that they're gonna eat themselves off and you fail to catch them, they are going to break something, potentially their spine. So if I'm handling them on the floor, not only is that less stressful for them, but if they do heat themselves out of my arms, they haven't got very far to go. I know that, I mean, it's probably a bit more of a rarity, but I know that there are obviously some clients, who might be a bit more elderly.
Who might not, want to, or might not be able to, sort of sit on the floor with you whilst you're handling them. But I actually have had quite a lot of clients, be very grateful that I'm handling their pet on the floor, want and very understanding and very, Oh, no one's ever done that before. Oh, right, yeah.
OK. That makes perfect sense. And that then builds you a little bit of rapport as a rabbit savvy nurse or rabbit savvy vet.
So how are we keeping their normal routine? My practise has a, a pre-admit questionnaire. So if they are being hospitalised, do they, are they outdoor?
Do they just toilet wherever? Do they have a litter tray? Are they, do they drink water from a bowl?
Do they drink water from a bottle? So how are we keeping their normal routine? Ask the clients to bring in a, a packed lunch and just, try and keep everything as normal as you can.
Our clients aware of stress and bunnies is such a big, big topic that I genuinely could do you another hour on, but. I very obviously don't have time. But all your clients wear stressed bunnies?
These guys, so, rabbits are quite often housed in not ideal situations, particularly those that are just kept in a hutch at the bottom of the garden because they were an Easter present for a kid some years ago. But these guys will live with some level of chronic stress, and then bringing them to the practise is an acute incident on that, and that is what can then tip them over the edge. Something that I should have mentioned when we were talking about handling, but the tonic immobility, so the tipping them upside down, that is not an acceptable method of restraint.
What's happening there is the equivalent of a giant picking you up by your hair, tipping you on your back, and you panicking with such extreme, like, such extreme, intent of, Oh my God, I think I'm gonna die. It's the fact that you freeze, you completely freeze. So that's tonic immobility and it's not an acceptable method of restraint.
So in the same way that scruffing cats is not an acceptable method of restraint anymore, tonic immobility, isn't either. So, this is what you actually wanted, rather than me yapping on, about stress in rabbits, but it's the, probably the leading cause of per-anesthetic mortality. So, pre-anesthesia, so I've got my ASA classifications here for you, but pre-anesthesia, we want informed consent.
Speak to clients about rabbit anaesthesia and about the potential risks and speak to them about, are these guys a do not resuscitate. Now I know that that's not necessarily. Something that's on all of your consent forms, but if you can get to the point of, Being able to have that conversation and.
Talk about it, not to frighten the client. But just to be able to talk about it in a way that they. They have informed consent for you to anaesthetize that patient, I think that's important.
Making sure that you've got the correct patient and the correct procedure, so that's something that I will always, always, always, get the client to identify this is this rabbit, particularly if they've bought in two. I have, worked at a practise where there was an era whereby we anaesthetized the wrong rabbits, because the client had, well, basically, the, the client had written on the consent form, grey one is fluffy. And then there was, obviously, there was a, a greyish one.
And, well, a grey and white one with more grey, and a wine grey one, and basically the client had mixed them up. So. Make sure.
So, in that situation, what I would have done, and it, and it wasn't my mix up, but I, I was part of a compound of mistakes that led to the error. But what I would have done is, in the case of two patients, I would have got both patients out and said to the client, right, which one is fluffy? Got the client to say, this one is fluffy, and in front of the client, I would have clipped their ear ready to place the IV.
We want today's weight, because that's gonna, indicate a little bit toward their hydration status. So we do want today's weight. And I would find that more important than doing, a temperature, definitely.
TPR, if we can. If not, just have a quick listen to the heart. If you are gonna struggle to count their heart rate, just count over 5 seconds and times it by 11.
If nobody's taught you that trick yet, then there you go. And handling, as I say, we're not doing tonic immobility, we're not tipping them on their back. We wanna make sure that these guys are in as normal a situation as possible.
So venous access, the most commonly used one, it is not the only option, but the most commonly used vein is the lateral ear vein. So the marginal or lateral, aricular vein, that's the most common. As you can see on this picture, this rabbit's obviously got really good vas vasculature in her ear.
Don't let anybody tell you that you can go for this middle one, because the middle one is the central orricular artery. So unless what you actually want is an arterial blood sample or you want to establish, arterial access for invasive blood pressure monitoring. You don't want that central vessel, because any drug that you give into that central vessel is basically going to go straight to the heart.
And it's going to hit hard. So, marginal lateral auricular vein is the one that is most commonly used. You can also use the cephalic in these guys.
So, a 22 gauge or a 24 gauge catheter, so a blue or a yellow, usually works quite well. The only thing I will say about the cephalic is that these guys are obligate nasal breathers. So just be very Aware in terms of how you're handling them, particularly in patients that might have come in with drocystitis or rhinitis or something like that, if they're already going to struggle to breathe and their respiratory rate is already up because they're stressed, maybe picking a cat maybe placing a catheter somewhere where you have to be quite close to their face is gonna stress them out a little bit more.
So just consider that. Lateral sepfius, if I, so if I can't get an ear, I would then choose lateral sinus. And the way that I would do this, I do actually need to get a picture of this, but effectively, this is one of the few times that I would put a rabbit on the table.
And I would stand them, so the person holding would have them supported against their body. But basically, they, I would let one hind limb drop off the table. So rather than doing a lateral sinus where you literally have to make them lie down on their side, because that's very stressful.
And also requires a lot of manhandling or whatever. But I would get them to stand as normal on the table, closer to the edge, but with somebody holding them. And I would let the, the hind limb sort of drop off below the table.
That does mean that I'm then placing the IV probably one nel on the floor, but. What is veterinary nursing, if not learning to do all sorts of contortionist activities and still manage to get that blood sample. But also it means that, the rabbit is in as normal a position as possible.
So, it's quite a decent vessel. It's good for blood samples, because it's, it's quite robust. I prefer it to the cephalic because it's bigger and I'm not in their face as much.
But that's not me saying I wouldn't use the cephalic. If we're taking bloods and we can't hit any of those, then I would consider the jugular, but I would just be very aware of the fact that if you, induce a hematoma in the jugular. Sorry, in, from a jugular stick, what you are potentially risking is, impairing the lymphatic drainage from the back of the eye, and that can lead to ocular proptosis.
So just be very aware that if you are using the jugular, make sure that we haven't got anything, weird in the way of coagulopathies. But also, I would be using a, a cold swab, to encourage vasoconstriction, after that jugular, venal puncture. Fluid therapy, are we doing a bolus every however many hours, or are we doing a CRI?
So are we doing it with a giving set, and a drip pump? For me, I prefer to do a bolus every couple of hours. I try to split it so that I'm doing it every 4 hours because that's when I would, at the very least, want to do my more invasive, patient checks.
But equally. If it's just something that's in for a routine, then we'll just work out a, a fluid bolus whilst they're, like, for, their per-anesthetic period, and give that over the course of whilst they're asleep. And then, let them, let them wake up.
The only reason why I have a slight hesitancy, with putting them on, a drip is that they will try to chew through it. There are contraptions and things, and there are little DIY makeshift things that you can create and concoct to try and stop them from doing that. And that's absolutely fine.
That's not me saying that you shouldn't be putting them on, on a, a CRI of, of fluids. But it just a, just a thought that comes into my head. That's all.
So subcut fluids, somewhere between 30 to 60 mil divided into two sites. It very much depends on the weight of your rabbits, but also we want to make sure, I mean, these guys do have a fair amount of subcutaneous space but in anything that is dehydrated. I mean, I had one a few weeks ago where the subcutaneous space, I think I needed to get 70 mLs into this rabbit.
It was a, it was a decent amount. But basically, he also had some respiratory compromise, and so I ended up, rather than just covering his entire back in all of these, oh, I've stabbed you, or I've stabbed you again, or whatever, I didn't want to cause any, Any further pressure, or any further insult to, his respiratory system by trying to cram more fluid, between his skin and the outside of his rib cage. So, but I did, I was slightly less and then a few hours later came back and did the rest.
Oral fluids, some clients, especially, cat and dog clients, but some clients are obsessed with when their animal stops drinking. But then they'll say that, oh, yeah, he's actually on 12 packets of wet food a day. But I've been syringe feeding him water and he didn't want it.
And like, yes, obviously. It's like me having soup every single day and somebody asking, why don't you want a, I don't know, a drink of water? Because he, he's on a liquid diet anyway.
But there is a risk of aspiration. So just be very aware of the fact that if you are syringe feeding these guys, that we're making the, consistency up to what it says on the packet. One for the reason of the calorific content will then be correct, but also there is a risk of aspiration if it's too liquidy.
IO, we can do, but maintenance might be difficult. IO is something that I've only really used in emergency situations. And intraperitoneal, again, we just need to be very aware of the fact that there is going to be greater pressure on the diaphragm.
And it's not gonna be particularly comfortable, to, to receive intraperitoneal fluids in a conscious animal. There's also quite a lot of guts in there. So, if you are gonna have to go IP, just be very, very aware, that there is a lot more gut in there than you probably suspect.
So induction and maintenance pre-med combination is going to influence a lot of what happens from here on in. So for me, the way that I would prefer patients to come into the hospital is we would admit. We would clip the ear, and apply Emler ready in the consult room, so that then the client is like, Yes, this is definitely this rabbit, blah, blah, blah.
And sit them in a kennel. I, will put something non-absorbent over the EA cream. So, I don't know, a little bit of syringe wrapper, and I'll tape it on.
I will write the time on in which I applied it, and then I know that I can't jump the gun. So I would wait 30 to 40 minutes before any attempt to being a puncture, and go from there. .
I only really use EmLA out of habit. I don't have a significant preference of that over the freeze spray. But I do think that with the freeze spray, because you're gonna get a little bit of vasoconstriction, I think you're probably giving yourself, a slightly more difficult task, than if you are using ELA because the EA's gonna cause a slight vasodilation.
And so in something small like a rabbit, you're gonna have a little bit of an easier time with that. So, Pre-med combination, it's very, very much gonna depend on what you're using, what you're used to. And this, I'm not gonna sit here and say, this is what you should be using to anaesthetize your rabbits.
However, what I will say is that gassing rabbits down, just using volatile agent, and just putting them in a, a box is an excellent way to kill them. So, if you, if that is your protocol, you definitely need to review that, in my opinion. Because it's anything that, smells bad, like Io or even Sivo, and anything that is gonna cause them significant stress, like being shut in a little box, that is potentially gonna cause them to breathhold, and that is then going to basically shorten your desaturation time.
And Potentially just encourage the rabbit on his way out. So once they've come in. And they've, hopefully had the IV placed.
I will try to reduce how many injections, I'm giving to these animals that they are actually going to feel. So, if I can get an IV in, everything that can go IV, I will be giving IV. I don't want to be doing, I know there's obviously, there's a lot of, drugs off licence and things, and there's a bit of a a grey areas, oh, OK, what are we doing pre-op meticca, are we doing pre-op metoclopramide, are we, and there's obviously everybody has their own different protocols, but for me.
The more injections we're giving to these animals, the more stressful that is. So, I prefer some kind of combination of an alpha 2 and an opioid, which I would like to give IV, and then some kind of, dissociative agent in the form of ketamine. Now, either I would give, all those three as, as IV, when I'm ready, so effectively a triple.
Or if for whatever reason we couldn't get an IV, in the rabbit because he was too stressed, then I would do the, opioid and the alpha 2 as an IM. And then once they are asleep from that, then I would do the ketamine, either IV or IM, and as the induction agent, almost. You can use propofol, but you are potentially inducing, bradycardia, which is, it's.
They're gonna struggle to compensate for the bradycardia, effectively. Whereas if we are using alfaxolone, you still, maintain, the, the cardiac reflex of, oh, OK, well, hang on a minute. Everything's going to sleep, my blood pressure's dropping.
Let's increase my heart rate. So you still have that. So, induction agent wise, again, I don't really have a preference, but just be very aware of whatever you're using, just have a think about.
How are we impacting this patient? We absolutely have to pre-oxygenate these. Guys, so for me, once I've got the Emma cream on, if I know that it's a patient that is gonna go straight through to theatre, then they can sit and chill in the oxygen tent.
Just be aware of the fact that the oxygen tents often. So as soon as you open that door, all of the oxygen floods out. Imagine that you are filling that tent with water, and every single time you open that door, you are, all the water is just spilling out.
So just be very aware of, yes, you can put them in the oxygen tent. But don't leave the door open and assume that that's gonna be OK for them. Temperature management, we don't want them too hot.
We definitely don't want them too cold. So temperature management, they're gonna lose a lot of heat, from places like their ears, from their feet. And so just try and keep them as warm as we can, but just be very aware of the fact that they don't have sweat glands in the same capacity as we do, or in the same capacity as dogs and cats do.
So just make sure that if they are getting a little bit on the warm side, that we're very aware of the fact that they will struggle to cool themselves down again, and that can also be fatal. Positioning wise, we are wanting their chest up in order to maximise their thoracic capacity. We don't want, .
We don't want them laid flat because basically all of their guts are gonna put pressure on the diaphragm and then they're gonna struggle to breathe. So thorax up by 30, 45 degrees, something like that, just so that we are maximising, that intrathoracic space. And then something that I get asked a lot is, do you prefer intubation versus a V gel versus a mask?
For me, it depends. So if it is a patient that is, I, I'm pretty confident that I will be able to intubate, whether that be via blind technique, whether that be using a, what do I mean? Like a, an in-ear, little video otoscope thing that, you know, the things that you get off Amazon that are designed to clear out your ear wax and stuff.
You can use those, those are pretty good. They're also very good for examining the backs of mouths. So for me, I would prefer intubation.
A V gel is something I would only use if I had capography. I would not consider them safe without capnography, but that's just me. If for whatever reason I didn't have capnography and I couldn't intubate the patient, then a tight fitting mask will suffice.
So, again, even in, in CPR situations, a tight fitting mask is where I would go with this. I wouldn't be faffing about with trying to intubate, a, a rabbit that was, in cardiac arrest. A tight fitting mask, will be good enough.
But just be aware of the fact that if you are using a mask, the environmental contamination and the potential health and safety risk for the staff. So just have a Have a little bit of a, a way up of what, what you can do. So monitoring Pulse oximetry, we're not gonna be able to see cyanosis until we are at way past life-threatening levels of hypoxemia.
However, what we're looking for with a pulse ox, I'm just gonna double check that I haven't, yes, I have. OK, fine. I'm not gonna yap too much then.
But what we're looking for with the pulse ox is a nice trace, and I'll talk to you about that on the next slide. Capnography, 35 to 45 millimetres of mercury is what we are aiming for. That's in a, a conscious patient.
Quite a lot of the time in rabbits, you will see that, that number is lower. That's probably because if we've intubated them, we're using an uncuffed tube. You can use a cuffed tube, but a lot of the time, it's, I don't know, it'll be like a 2.5 or something.
So, they don't have a cuff in those sorts of sizes, or the practise doesn't. But you'll end up, with some, environmental contamination and some, dilution of that carbon dioxide. So it might be that it looks like your readings are lower than that.
But the same as in cats and dogs, we do have the permissive hypercapnia up to about 50 to 60 millimetres of mercury. Non-invasive versus invasive blood pressure with these guys, I've very rarely done invasive on rabbits, but when I have, it's the central orcular artery that I've used, . Sorry, the Doppler, ideally preferred to the oylometric, mostly because you can actually hear it and the occiometric might struggle because the pulse is, in something so small, it's not, it's not necessarily designed for that.
Or calibrated to something as small. ECGs, a second degree AV block is fairly common, especially if we, have got something with, where we've included an alpha 2 in our protocol, and I'll talk to you about that, in a little bit. And then reflexes, these guys have slightly different reflexes that we would be looking for.
So, that is also one of the other reasons that I think rabbits get a bad rep for just dying under anaesthesia. I think sometimes we are genuinely looking at the wrong things. So, we'll have a look at pulse oximetry.
I'm not, because I'm gonna run out of time, I think. I'm not gonna have time to go through the ins and outs of how it works and all of that sort of thing. But pulse oximetry.
It works, the probe works really well on the tongue, or on the toe or on the ear. It might have a little bit of an issue with, a rabbit's really high heart rate. But what you are effectively looking for is this kind of, like, bi-lobed double mountain looking thing, on this picture.
And what you are looking for. So that, that would indicate that I've got a good trace. I know that some people would prefer it to just look like molehills, but that's not, an accurate representation of how, how good a contact we have.
So if you've got, a trace that looks like this one, I've got a picture of, that very obviously I drew on clip art, then, sorry, on, on paint, then that shows that you have got a good trace. It will be affected by LED light. So if you've got a rabbit in for a dental and somehow you've managed to find enough room to put the, the probe on their tongue, but then you've got an LED light shining straight at their head, it probably will be double or triple counting, and it probably won't read.
So just make sure that, I mean, I, I've got a picture somewhere of, the dental table has a heart rate of 200 and something. And it's literally just because I've left the probe on the table, as I've taken the pet back to his bed. And the LED light from, like, the overhead dental light is shining on my, on my probe, and it's just decided that that's what that is.
OK, fine. Whatever. My table has a heart rate, no, no stress.
But just be aware that these clips, if we have only got one size SBA 2 probe clip, sometimes the clips are a bit big and the spring is a little bit too forceful, and so it can cause vessel compression, so you can get a dampened wave form over time, and you can get a slightly less reliable trace over time. So, just to make sure that we're moving it so we're not accidentally causing any ischemia. Topnography, as I said, I would always, always, always use with a V gel.
I won't have time to go through the ins and outs of, the, the different traces and things, however, what you are likely to see is either re-breathing because these guys are breathing round the tube, or because they are, tiptnick, so they're hyperventilating. Or you would potentially see, rather than your nice castle turrets, you would potentially see more spikes, and that's because if they're not positioned correctly, spikes or shark fins, if they're not positioned correctly, you're more likely to see, that impact in their reduced, thoracic capacity. So.
You'll see a difficulty breathing in, and potentially even a difficulty breathing out depending on the positioning, but certainly a difficulty breathing in because there will be pressure against their diaphragm. If there is a lot of dead space, you can increase the sampling rate, of your capnograph depending on what monitor you have. It will be in your manufacturer instructions for your monitor, because I, funnily enough, I don't know off by heart every single, .
Monitor. And so I don't know, how you would change that on your specific machine, but you can do that. And just being aware of, when I talk about dead space, what I mean is anywhere where there is bidirectional flow of gas.
And when we're talking about anaesthetizing something as small as a rabbit, we are probably using a non-rebreathing circuit. So we've probably got a T piece on. And so we need to make sure that, one, the fresh gas flow rate is at an adequate, level.
And remembering that our fresh gas flow rate will increase if our patients respiratory rate increases and can decrease if their respiratory rate decreases because of how we calculate fresh gas flow. But Despace, if you've put any additional connectors in, so that I don't know, your capnography attachment or you use a HME or whatever, just be very aware that that instantly creates turbulence within the system and can also make it more difficult for that patient to breathe. So, just having a think about.
How much dead space there is and how we can adapt to that. So, as I said, so this top one is hyperventilation. I'm just gonna call myself out here, neither of these, are rabbits, these are both dogs, but these were good examples.
So, this top one, is hyperventilation, and so we've got rebreathing, we've got, hypocapnia. And that is quite common in one, in rabbits where they are struggling to, breathe properly because of, the pressure from their guts on their diaphragm, but also in the instance of pain. So just because these guys are asleep doesn't mean that they aren't going to be able to exhibit no susceptive responses.
So no susceptive responses are, that's the physiological response to pain, whereas pain itself, is, that's the emotional experience that comes alongside it. And then this bottom one, this bottom one is, again, this is a dog, but we've got difficulty breathing in, difficulty breathing out, when actually what's happening here is this patient's breathing round their ET tube with such significance, that it looks like my end title is 9. So in this case.
I, I cuffed the ET tube and we came back up to normal. But just so that is quite common. The bottom, trace shape is quite common in rabbits, because there's probably gonna be a little bit of, dilution and contamination, purely because we've been able to get a little tube in, that's all.
Blood pressure, so when we are fitting the cuffs, we wanna make sure that they either are 30 to 40% of the circumference of the limb, or that when you are folding them over, they fit within that little index line section. There's a couple of papers, that sort of talk about the ins and outs of, obtaining accurate oscillometric blood pressure measurements in rabbits. The most reliable paper that I could find, was talking about using the occiometric cuff, above the elbow.
And that's great in a lab setting where you have pretty much got all the same species, all the same breed of rabbit, and they're all a similar size. Whereas here, I've got some kind of dwarflop, and there's no way that that cuff was ever going to fit above her elbow. So, that cuff is below her elbow.
. And what we're looking at is trends. So, in the same as dogs and cats, we're not looking at one value. We're looking at trends.
So these guys, we would consider hypotension in rabbits to be below 80 millimetres of mercury. That's when we would start, considering treatment. And whether that be with an anticholinergic because they're bradycardic, or whether that be, with, what do I mean?
Reducing the volatile agent, or whether that be, with a fluid bolus because we're suspicious of dehydration. That's obviously situational. But, yeah, dogs and cats, we would consider hypotension at 60 millimetres of mercury, for a map and, for rabbits we're looking at 80.
The ECGs, you can use the atraumatic clips, but sometimes it means that you have to completely douse your patient in spirit, and obviously we don't want to do that. You can put the crocodile clips on a needle as it goes through the skin, which is what I've done in this picture here, because then you don't need to douse your patient in spirit. But obviously just be very aware of the fact that you've now basically created a porcupine.
So please, if you're doing this, either put the cap on the needle the wrong way round. So you're stabbing through the, the roof of the lid. So that you, I'll, I'll find you a picture, but yeah, you're either stabbing through the roof of the lid, so that the needle tip is covered, or please only do it when they are fully positioned, and not when you're having to wake them back up onto that, little dental table contraption thing all the time.
You can use the sticky pads. I prefer not to use the sticky pads because, one, they don't really get that good contact. I prefer sticky pads in dogs and cats, but for rabbits, I found that they don't get that good contact.
And if I am using the sticky pads, I'm basically having to clip, to, to place them, and I don't want to clip the bottom of their feet because then that's leaving them open to podo dermatitis, because they don't have the same keratinized pads that, dogs and cats do. So this was a video, that I blew up, obviously quite big, which is why it's blurry, so I'm sorry that it is a little bit blurry. But, basically, I just wanted to point out that rabbits, that, I mean, again, I've cheated, and this is a dog.
But, rabbits that. 70% of domestic rabbits have an enzyme called circulating atropinase. Now.
That means that when if you were to give atropine to these rabbits, it will be broken down by this atroponase by the time it has even got to where it needs to go, so it effectively won't work. However, glycopyrelate, they don't have any enzymes that's gonna break that down. And so in the face of a second degree AV block where you've got bradycardia and you've got hypotension.
You would be more inclined to use glycopyrolate to treat this in a rabbit rather than atropine. However, not every practise has glycopyrolate. I can count on one hand the number of practises I've worked in with glycopyrolate.
And yeah, not everywhere will have that. So if you have a rabbit that is bradycardic and hypotensive, has a second degree IV block or it's crashed, and you don't have glyco. It is OK that you use atropine, because you don't know if that patient is in the 30% that actually, will respond to the atropine.
You don't know that. And so, giving it a go is the best thing that you can do. So, that's just why I wanted to mention, glyco or, or atropine in that context.
Reflexes. So, I'm not gonna give you, cause you can take a picture of this or screenshot or whatever. But I, I'm not gonna go through everything on this, but obviously, the writing reflex is the first thing that they tend to lose.
The palpebra reflex is not particularly useful, because sometimes it's there and sometimes it's not. Swallowing reflex, you're not gonna be able to assess, jaw tone's gonna be difficult to assess. Corneal reflex shouldn't disappear.
I really hope it doesn't disappear. Ear pinch is what I would use, and I would also use the hind limbedal reflex. So the ear pinch is literally where you would pinch the pinna, and if they're not at a surgical plane of anaesthesia, they will shake their head.
Pedal reflex, I don't know why I've asked neurologists. I've asked exotic specialists, I've asked anaesthetists. Nobody can tell me why, but the forelimb pedal reflex retains its, ability to, it it basically is still present at deep plains of anaesthesia, whereas the hind limb.
Doesn't tend to do that. So the ear pinch is what I would be using, combined with the hindliedal reflex. An eye position, because we've got ketamine involved in a lot of these protocols, we will not be able to use eye position as a particularly useful, what do I, a particularly useful indicator of anaesthetic depth because ketamine causes centralization of the eye.
So for me, it would be ear pinch and hind impedal reflex, combined with a little bit of respiratory rate, heart rate, etc. So this was just a quick slide to show you, the monitoring, and how I've managed to adapt it in different situations. So this first one is a rabbit that, we've anaesthetized and, we couldn't intubate.
We didn't have, V gels in her size, so we've used a tight fitting mask in this case. And I've just put the capography line inside the mask. I just want to draw attention to the fact that the mask does not encompass half of the rabbit's body, because that is a ridiculous amount of dead space.
They don't need that half of their body inside the mask. They're obligate nasal breathers, and so arguably even this mask is a little bit big, but. It was the smallest one that we had.
The blood pressure cuff I've already spoken about, and the fact that this one was placed below the elbow, because we're looking at trends with these guys. And then this video is just me demonstrating the hind liedal reflex in a rabbit that is waking up from anaesthesia. So she pulls away as I squeeze, and she's she's waking up nicely.
So a little bit on post op, oh sorry, a little bit on post op, these guys have, as I've said previously, they don't have any sweat glands, so if we're making them quite warm, they are going to struggle to cool themselves down, so we need to keep a close eye on their temperature if they have become cold. These patients, if they are comfortable, will not be interfering with their wound. You can put a buster collar on the ones that are particularly mischievous, but it does mean that they will not be able to perform, kika trophy, so we will be, preventing one of their natural behaviours.
So just something to think about. Intervention if, they're not eating, for 4 hours post-op, whether that be due to pain, whether that be due due to drowsiness, we need to be thinking about how are we going to intervene. So either through syringe feeding, again, make sure that we are reconstituting the syringe feed to the correct, like to the manufacturer instructions so that then we know what the caloric content is and we know how much they should be having.
You can place an NG tube in these guys. But again, they're obligate nasal breathers. So they just have a think about, are we putting in the biggest tube possible, and then we've just blocked an entire nostril and wondered why the poor rabbit's stressed.
And then faecal monitoring for me, is one of those things where if I locum, and I, I'm monitoring a rabbit with gut stasis or post GA or whatever, and I asked where the sandwich bags are. I always get a bit of a weird look, and effectively what I do is I will collect faeces for that patient. Over the period of my shift.
And so, I don't know if I'm day shift 8 to 8, then, I will, this, this is sandwich bag for day shift 8 to 8. Then I'll ask the night team to do the same, and then when I come in the next day and I, and, and you can see the progression of not only, the quantity of the faeces, but also the quality. So, is it dehydrated little pellets?
Is it diarrhoea? Is it improving? Has it gotten worse?
So if they are staying in and they're hospitalised over a period of time, that's definitely something that I would be doing. And I know that it makes you seem like a mentalist, but it definitely, definitely, does help and does work. And also, if you've got, some, quite involved rabbit clients, they will also be interested, and it means that you can show them, sort of the evidence of, no, no, no, look, he is improving because this, this and this.
So In summary, If I was gonna pick one main point, it would be stress reduction is the main thing with these guys. They are not just little dogs. They are not just little cats.
They are their own species and need to be treated as such. They have species-specific idiosyncrasies as well as patient-specific idiosyncrasies, and we need to make sure that we are able to adapt to them because as nurses, we are their voice, and that is what we are here for. So, stress reduction is a huge, huge thing.
We can mitigate anaesthesia risks. And realistically, that's all we're doing with dogs and cats, is we're just mitigating the risks. So making sure that we are prepared, making sure that we are able to use the monitoring equipment and troubleshoot it appropriately.
Making sure that we're able to monitor the reflexes of these patients in a way that is suitable for them. There's no point saying, Oh, yeah, well, he's, I can't tell what, what his jaw tone's like. OK, use a different parameter.
So just being able to use the monitoring equipment, but as an adjunct to you, is, is hugely, hugely important. Considering the effects of your drug combinations, so. Giving things, whacking doses, and wondering then why they're hypotensive or bradycardia or whatever.
So just consider the effects of your drug combinations before you've given them. And if that means that you go away from here and you have to consider, I don't know, a, a staff meeting to talk about what your current rabbit anaesthetic protocol is, or, I don't know, vet one does this, vet 2 does this, vet 3 does something completely different. Just sit and have a think about, what did I like about vet one's protocol?
Or what do I like about vet and why does vet 3 do that one? And just start a conversation. About why, why are we doing it this way, why are we doing it, because if the answer is, oh well, we've always done it that way, it might be that there's room for a little bit of sort of critique in there, because have we always done it that way because it's the right thing to do, or have we always done it that way because we don't know any better?
Post-op care and monitoring, pain relief, please, please, please. So analgesia, analgesia, and one more time, if you didn't hear me, analgesia. So post-op care, there is no world in which we will be able to, or at least not, probably not one that I'll be nursing in.
In which we'll be able to accurately assess low grade pain in rabbits, because they are so, so adept at hiding it, because that's what they are biologically designed to do. And so I think it's probably fair to say that if we assume that they're in pain, if that's something that would be painful for a dog or a cat, then let's give that analgesia. Let's not withhold analgesia because they look a bit too flat to receive it.
So. Just make sure that we are appropriately pain scoring and using our nursing knowledge and nursing know-how, in order to provide adequate post-operative care and analgesia. So I'm more than happy if you guys want to drop me a message on Instagram with any questions, or you can, send me an email.
It's literally, the veterinary nerd at Hotmail.com. But I'm hoping that I've answered all of your questions.
But I would be more than happy if you wanted to send me a message, and just let me know, how I can help. Thanks very much for listening.