So thank you very much for joining us. Today we're going to talk about analgesia options for dental surgery. We're all performing dental surgery, quite likely on a daily basis, and I think we can get stuck in this is how we do things, knowing that we could do it a little bit differently, potentially a little bit better, but not really knowing what our options are, and we're so busy that trying to find these answers can be difficult.

So hopefully if going through this webinar together we'll give you some more options and a bit more confidence, then that's fantastic. So thank you very much for the webinarve for having me. I'm very grateful to speak for you once more.

So webinars can be a little bit strange because you can't see me and we're not face to face, but hi, I'm Stacey Parker. I'm a registered veterinary nurse and I qualified in 2014 in the UK. I have achieved my ISFM certificate in feline nursing, my NSA in anaesthesia and dentistry, and I'm currently halfway through my advanced anaesthesia certificate.

My official job role is a referral, anaesthesia and dental nurse, and I also work out of a few emergency clinics, and I provide in-house and external CPDs such as this and lots of learning aids and patient warming packs. You're very welcome to contact me directly or obviously through the webinar vet at any point, if you'd like anything further explained, or if you just wanted more information or just to chat about an interesting case, you're very, very welcome to contact me in any of the above ways and there'll be a contact page at the end as well. So I work at the moment predominantly at Perry Referrals, a specialist veterinary dentistry and oral surgery business, and we are very, very busy with lots and lots of dental cases.

So I'm hoping that my experience and chance of the education I've had by working with lots of anaesthetists and dental specialists, to really give you an insight as to what we do and why to open up your options and clinic. So Perry Referrals currently works out of North Down Specialist Referrals, which is a multidisciplinary referral service in Bletchingley, which is in Surrey in the UK. And we're super lucky to work within such a varied team there.

So let's get started on the reason that you're here. Let's talk about pain. We're not gonna get too scientific.

I really want you to be able to walk out of this lecture knowing more about what you can do for your patients and really have more of a practical element of how you can improve things. But pain basically is an unpleasant sensory and emotional experience, and we've all had it. It's not pleasant, so we definitely want to stop our patients having it where possible.

There's also chronic pain in our patients the dentistry are quite likely to have been in pain for some time. Perhaps the wait lists for dental surgery was quite long. Perhaps the owner wasn't aware that dental was needed until they came in for a vaccine, or perhaps the owner took quite some time to get their head around the fact that their animal would need this anaesthetic to have this dental.

There's lots of things that can cause pain in dentistry, so mobile teeth, resorptive lesions, fractured teeth, tumours, even when we're just scaling the teeth, it can be quite painful. Fractures again, but more so fractures of the jaw, abscesses, exposed roots can be painful, and the procedure of root planing can be quite painful. And obviously when we're performing surgical extractions or our vets are, that's painful too.

So you can see there's a really long list as to what can cause pain with dental, . Procedures and dental disease processes, so we really want to make sure we're on top of that as soon as possible. There's many reasons why we want to alleviate the pain.

Being in pain can actually delay healing. It's emotionally distressing. It can cause our patients to perform self-trauma, which will cause even more problems that we then need to try and fix.

They may have the inability to eat if they're very painful or if they've been left painful after surgical extractions. And also being in pain really does make you feel miserable. We've all been painful, it's not a nice experience and it really does lower the quality of life and they don't understand that they're feeling painful just because their tooth hurts.

And also, if your patient is in pain, it really makes for a really difficult anaesthetic. So if we can alleviate pain, we're not gonna need so much inhalants. We're not gonna be needing so much anaesthesia drugs, so our anaesthesia is actually going to be much more pleasurable, and not as challenging.

There's many signs of dental pain in our patient. They could be favouring one side when they're eating or carrying their toys. They could be hyper salivating, they could have haliatosis, so really smelly breath that isn't normal, you shouldn't just have doggy or cat breath.

They could go to eat and want to, but be refusing because they know that every time they do it just hurts and they no longer feel like it's worth it. Conversely, they can actually eat very fast, and particularly with cats, they just really quickly eat the biscuits and they're not actually chewing them, they're just launching them with their tongue to the back of their mouth because they know they need to eat to survive, but they don't want anything touching their teeth, and quite often those cats will then vomit quite surely shortly after eating. They might not move around as much, I don't know if you've ever had dental pain I have and it's miserable your whole head feels heavy and it really affects everything, so you certainly don't want to be jumping around.

They could be pouring at their face, they could have a change in character, and sometimes they can have the most horrific mouths that need multiple extractions, and actually there's not many clinical signs, it's only the owner afterwards says oh they're actually much brighter, I hadn't realised and they're a lot happier. Pain scoring is super important. We need to be able to quantify what we're doing.

So this is one of our patients that came in for a consultation, referred to us for gingivo dermatitis, and we see many, many of these cases, and I think you agree that this handsome boy, as handsome as he is, he doesn't look happy at all, and we do utilise our pain scoring charts, so I thought maybe we could go through one together. This is him prior to any pain relief, we're gonna give him a pain score, and then we're gonna give him some methadone and we're gonna have a look at him afterwards and we'll pain score him again. So let's go through this together.

So question one, obviously I need to help you with this one, but is the cat silent, purring, meowing, or is he vocalising in any way now, he was very, very silent, he wasn't growling at us. He was just completely silent and withdrawn. Would you say he's relaxed or licking his lips, restless, caring at the back of the cage?

Is he tense or crouched, or is he rigid and hunched? I think we agree that this guy here is rigid and hunched. That already gives us a pain level score of 4.

Question 3, are we ignoring any wound or painful area? Most cats won't scratch at their mouth. It's more when it's nerve pain that they're scratching at their mouth, or if they've had extractions where roots have been left behind.

Commonly that's going to cause them to scratch. Peridontal disease, they don't tend to rub at their mouth because they're quite clever and they know the more they do that, it actually hurts more. So this guy isn't actually paying any attention to the wound.

But bless him, he's not really paying attention to much else. So looking at our caricatures at the bottom, which would we say depicts the cat's ears position the best, and I would say this would be #2, he's got really flat down ears. And B, look at the shape of the muzzle.

He's got a very, very tight muzzle with his whiskers really drawn close, so again I would be on 2. We're gonna approach the cat, call him by name and stroke along his back, and does he respond to stroking, stroking, or is he unresponsive or aggressive? He didn't respond, he, was just completely unresponsive, even though he was very uncomfortable.

He didn't become aggressive. So it then says if the patient has a wound or a painful area, apply gentle pressure around the site. So we had a look at lifting his lips to see how he felt about that.

And he did cry when we do that, so that's at least a 2. The general impression of this cat, I think you agree is that he is very depressed or grumpy, potentially dull. Either way, this pain score is coming out of a total of 20.

Of at least 12+, and with this pain score we should be having an analgesia intervention of a score above 5. So this guy needs some pain relief quite quickly. So we gave him some post IV, he's a very good boy, and we gave him 0.2 mg for methadone slowly intravenously, which is off licence, but all our patients are signing consent forms for the use of unlicensed medication according to the cascade.

So this video will show our handsome chap after he's had some methadone, and then we can repay and score him. So you can see his ears are up, his whiskers and muzzle are more relaxed. He's even making little puddings as you can see with his front paws.

He looks a bit nervous, but I think I would too, within the veterinary clinic, but he's even holding his whole body up more as well. So we've repainscored him and he's at a 2, so his intervention is, been a success. We don't feel the need to add in any more analgesia right now, but we will of course prior to his anaesthetic.

There are other pain scores that you can use for dogs as well. There's multiple ones out there and we actually use them for all patients and we have them laminated, so we can reuse them and put them on the front of the patient's kennel. So let's talk about the drugs that we can use.

There's multiple drugs, you may not have them all, you may not be used to them all. You may have them but have never used them, you may have vets that really dislike particular drugs. But we're gonna talk through a lot of them, we're gonna talk about doses, duration, reasons to use them, reasons to avoid them, and potential side effects.

Now you may think if you're a nurse watching this, that if only a registered veterinary surgeon can legally prescribe and choose these doses and routes of administration, then why do I need to know? Ultimately, we are the ones monitoring these patients, yes, under the guidance of the registered veterinary surgeon, but I still like to know what to expect from my drugs and also to work well as a team and to understand the drugs and the potential side effects and benefits for our patients will only improve our patient care, in my opinion. So I think it's really important anyone handling, using or monitoring patients with these drugs should have as full understanding as they possibly can.

We're gonna start with an alpha 2 agonist, so that's your Meatomidine and Dexedatomidine, and you may be thinking that that's a cesacean. What are you talking about? It actually has really good analgesic properties, both meatomidine and Dexedatomidine.

We use the two of them. It's quite an anaesthetist dependent. I'm quite happy with both of them.

I will always draw up the antecedent, the Atipa for any alpha 2 that I'm using, just in case I should need it. Now alpha 2 will cause a dose dependent sedation, muscle relaxation, and an element of analgesia, and combined with an opioid, it offers improved sedation and analgesia. And that's another reason why we like to use quite low doses of alpha 2.

We don't need to reverse it, and that means the analgesia is still on board as well. We use very low doses in our clinic.As 2 to 5 mcg per kilo IV.

It's very, very low. It will last about 45 minutes to an hour. I remember you can top them up very gently, and we don't go anywhere near the big doses that you'll see in the data sheets.

Dogs 1 to 3 mcg per kilo IV. Of course if you're giving it IM we all need slightly larger doses. We tend to use 10 to 15 mcg per kilo in aggressive patients, and if they just need a bit more of the edge taken off and I just need to be able to get an IV because they don't want to give me their leg, or they're a bit worried, and then it's 5 to 10 mcg per kilo IM for us.

And the duration is actually dose dependent, the higher the dose, then actually the longer the duration. But that doesn't mean we should be giving hefty doses just so it lasts longer. We can repeat it when needed, it's much easier to add something in, than to keep trying to reverse it.

And I think when you reverse an alpha 2, you're just heading for a really rocky road of an anaesthetic, and we tend to only reverse it if we've been a lot shorter than we thought we were going to be, and our patient needs to wake up and then we, we reverse it, in ramustically only. We never give this IV. It's too much workload for the heart.

But otherwise we don't tend to need to reverse it at all. There are side effects with any drugs, and we'll go through this for every drug we discuss. So your alpha 2 side effects are bradycardia, reduced cardiac output, and when the side effects is positive in that your mean alveolar concentration to how much inhalant you need to keep your patient asleep, will can be reduced by up to 70% depending on what other drugs you're using, what you're doing, and what dose of alpha 2 you used.

Now that's a good thing, but if you're not aware of it, you could very easily overdose your patient on your inhalants. Alpha 2s are not recommended in some cardiovascular disease, diabetic, pregnant patients, you do not wish to vomit, such as a head trauma, so think about your cases that it's appropriate for. And we've already discussed whether we reverse it or not.

So are youioids and mu agonists. So what does this mean? This means they have a high a pure mu agonist will have a high affinity and intrinsic activity for mu receptors.

So the affinity means the extent of which the drug will want to bind to its receptors, so a high affinity is good. That drug is gonna bind really nicely, which is what you want. The intrinsic activity is the ability of the drug receptor to produce a maximum response.

So we want that to be high too. So that's why we like the pure mute agonists such as fentanyl and methadone. We'll start with methadone, I think that's quite commonly used, particularly here in the UK.

This is, as we said, a good pure mute agonist. It's gonna work well when it gets to the receptors and it's gonna hold on well as well. It's really good for moderate to severe pain, and I feel like dentistry really does always fall into the moderate, closer to the severe pain elements, and we can't quantify it, we can't ask our animals how much pain are you feeling, 1 to 10, so I think we do have to really make sure we're covering them.

Doses for us, dogs and cats, 0.1 to 0.3 MB IM or IV every 3 to 4 hours, but it can become a little bit cumulative after a while, so make sure your pain's growing first so that you don't have a super high patient on your hands.

The potential side effects of methadone are respiratory depression and bradycardia, particularly if we're giving this intravenously as a top up under anaesthesia. But don't let that put you off, dilute it if you need to, give it slowly and remember that it will be quite transient and that you can reduce your inhalant once you've given an opioid under anaesthesia. If you give it to a patient when they're conscious, conscious, sorry, then they can start panting the way it works in the brain they then start to think they're a little bit hot, so, your dogs will start panting even if they're not actually hot.

So we don't like to give it when they don't need it, of course, and that's why we pain score first, so we're not just giving it because we think we should and then realising we're a bit stressed with panting, and we give our premedications intravenously where possible so that we avoid having too longer. Portion of time between pre-med and induction where they could start panting and become a little bit distressed. Fentanyl is another pure mute agonist.

It's 50 times more potent than morphine, so it works very, very well, providing profound intraoperative analgesia. It's a really rapid onset with a short duration of just 20 minutes. And you can either give it as a little bolus dogs to cats, 1 to 5 mcg per kilo IB or as a constant rate infusion, and that drug dose will follow.

Transdermal patches are also available, but you need to be super careful because we need to be keeping our patients nice and warm under anaesthesia, particularly for dentistry, and we can't make this patch hot or place it on any heat pads because it will vasodilate your patient and then they're going to absorb the fentanyl too quickly, which can be dangerous. The only thing with fentanyl, and I do like it as a drug, we don't tend to need to use it too much in dentistry because we are utilising local nerve blocks, which I will discuss with you shortly. You can see profound bradycardia with fentanyl, which can give you some brady arrhythmias, so just be careful, and they can also be quite sedated or a little bit high on recovery, so we just need to bear these things in mind.

With a constant rate infusion, you must be using an accurate syringe driver or if you don't have that, using a small bag of saline to add your fentanyl into and then using a drip pump, you mustn't just be pushing this through. The loading dose is 1 to 5 mcg per kilo IV, and then the. Constant rate infusion rate is 6 to 10 mcg per kg per hour IV during surgery.

That can then be reduced into the postoperative period. I normally reduce it about 1015 minutes before we're turning off the inhalant, to 1 to 5 mcg per kg per hour. We've discussed some of the side effects, but mainly respiratory depression, as with any opioid, bradycardia or even asystody, if you do give it too quickly, IV, which is why you need to have an accurate way of administering these CRIs.

Bradycardia can be overcome with the use of an antichonyogenic such as atropine or glycopromium. So it's not a reason not to use a fentanyl CRI, but it does highlight why we should be aware of the potential side effects and how we can counteract those. Now buprenorphine, we do use for post-op pain, we never use it preoperatively personally.

This is a partial mute agonist, which means it's appropriate for mild to moderate pain. However, unlike the methadone, you can't actually top this up, and it has a really high affinity, so it means it's gonna hold on real tight to those receptors. So if we wanted to use a better or stronger pure you, Agonist, after this, it's gonna be really difficult to expect say that methadone to work to its full potential because the buprenorphine's gonna be holding on too tight to those receptors to let it in.

Potential side effects of buprenorphine, it can be painful or on IM injection and it will be a larger volume than if you're using methadone, and it can cause mild sedation in cats. Dose wise, you're looking at 0.02 meg per gig, IV I am, I've put subcut with a question mark.

I'm not particularly a fan, and we can give it transmucosally in cats only, not with dogs. The pH in their mouth is different. You'd have to give quite a high volume, and even then it really isn't shown to be as effective as it is with our cats.

Duration is 6 to 12 hours, which is great. We often send our post-op, patients home with buprenorphine. And they have that, trans mucos every 12 hours for our cats.

Regardless of how you give this drug, it does take 40 minutes even if you're giving it intravenously to have its onset. So just bear that in mind if you have a high surgical case load, you do need to be planning these appropriately, to make sure that you're not in, you know, giving the pre-med, waiting 10 minutes, and then inducing them, because that 1st 30 minutes of surgery, the patient doesn't have its analgesia on board. Another drug you can use and it's quite commonly used, and we use this a lot as well is ketamine.

Now this is a dissociative anaesthetic with profound visceral and somatic analgesia. So it's really good for the tissues, and obviously there's lots of inflamed tissues in the mouth. Well you're looking at doses of 0.3 to 0.5 mg per kg as a bolus intravenously.

Now this will last for about 45 minutes of analgesia under anaesthesia. And we go slightly higher for using it as a co-induction of 0.5 to 1 mg per kg.

If you're giving it intramuscular, remember you need to use it with a muscle relaxant such as methotomidine or a benzodiazepine, such as diazepam or midazolam, and higher doses can be used for iron injection, particularly for aggressive cats. It does sting on injection, so just be aware, and the duration is quite short of 30 to 40 minutes. The side effects are given it intravenously, it does cause transient apnea, particularly if you're giving it quickly, and these doses will come to small volumes, so it is easy to give it quite quickly.

But don't worry, it is transient, so just be again aware of your side effects and be ready to perform a short dose of IPPV. It's max bearing, which is great, but again, just be aware you're not gonna need as much inhalant if you're using ketamine. There are some rare cardiovascular effects, so you mustn't use it for patients with HCM.

And it's also not appropriate for patients with raised intraocular pressure. It can cause muscle rigidity, so again, use it with a muscle relaxant, it shouldn't ever be used on its own. And it can also make your patient a little bit dysphoric or excited on recovery.

So just make sure that you're not waking them up too quickly. If you reverse an alpha 2, for example, 20 minutes after you give them a meatomidine ketamine, combination, then you're gonna have a cat or a dog that's incredibly high and quite difficult to manage. We often use ketamine CRIs if our blocks aren't working as well as we would like them to.

So that's 0.3 to 0.5 MB per gig as a loading dose IV and then 2.5 to 10 mcg per kilo per minute.

IV, as the CRI and again, this must be used with an accurate, accurate administration piece of equipment such as a syringe driver or a fluid pump, and again, 10 to 15 minutes prior to waking my patient up, I am going to reduce that ketamine down to the 2.5 mcg per kg per minute, so they're not feeling quite as dysphoric and the pain stimulus has stopped, so we don't need to have it quite as high. Non-steroidal anti-inflammatory drugs were all very familiar and there's several drugs out there.

They have a long duration of effect, so we just have to give them once a day, which is super helpful, and we can also give it orally, which works really well. However, if we've performed oral surgery, we don't want big chunky oral tablets going down, so our preference is normally the syrup version. It's an anti-inflammatory with no behavioural modification and no respiratory or cardiovascular side effects, which is great, and they're super easy for the owners to administer once you've shown them how.

You mustn't use this in combination with steroids and hopefully you've reduced or stopped steroids before surgery and realise that steroids have no analgesic effect anyway. If you're going between one non-steroidal and another, then you need to allow a washout time, so you need to have a look at the data sheet for your medication as to what that time will be. Of course there is the potential for gastrointestinal side effects.

This is why we have to direct the owner to give it with a full meal and to definitely stop it if they have any vomiting or diarrhoea. And I'd just like to say just because they had a reaction to one doesn't mean they're definitely gonna have a reaction to another. And I find that if they've had a reaction to say Rimido or Metacam, I found that Onsure actually seems to be kinder to the tummy, but that's just sort of one personal experience that I've found with my own cat and with other patients.

Do be careful using non-steroidals with patients in renal disease. You may need to reduce the dose and avoiding patients in shock with coagulopathies, risk of haemorrhage or dehydration or hypovolemia. And also speak to the owner, have they had a negative reaction to any medication in the past?

Have a look through their history because you really don't want to be sending them home, having injected them with Metacam, for example, and as you're giving the pot to the owner, they say, oh no, we can't have that, it makes him really sick, so make sure you've investigated that before. And we give our non-steroidal anti-inflammatory drugs postoperatively, once the blood, hopefully the blood pressure's OK, we need to make sure it's OK throughout the anaesthetic and support it. But for that very reason, we ensure that our patient has the anaesthesia has ended, they remained normotensive, and then they will be given their non-steroidal anti-inflammatory drug.

Something that is getting quite popular and we do use very regularly now is paracetamol. This is only for dogs, you must never give this to cats, they don't have the metabolite to be able to metabolise this and you will just cause toxicity. And also make sure that owners are aware that this must never be given to cats because you're sending a dog home with paracetamol and then the cat hurts their leg the next week, and then they think, oh yeah, you know, if Bluffy the dog had some paracetamol, I'll just give it a smaller dose of that.

So just reiterate and make sure it's on the label never to administer this to cats. And also just to be careful and let them know that this is a special doggy size paracetamol perhaps, and that it mustn't have any additives either. We use it as a dose of 10 to 15 mg per kg every 8 to 12 hours in the hospital, we give it intravenously, particularly obviously if they're under anaesthesia, and we can then send them home on 10 to 15 mg per gig every 8 to 12 hours orally.

And you can get the liquid formula for smaller dogs and also smaller strength tablets, teeny tiny little ones, are available for small dogs which cut really nicely into quarters as well. And it's very cheap. There's not many side effects, but you do need to be careful with patients with any co-existing liver disease.

Now Gabapentin's a personal favourite for me for my patients. It's really good for neuropathic pain, but it also is a really good anxiolytic. And we give it to a lot of our patients pre-operatively for their owner to be giving at home.

It allows us to place IVs easier, it allows us to reduce our premedication drugs, it allows us to reduce our inhalants, and it allows for a smoother recovery. I will say your recovery will be a little bit longer because there's sedative properties of gabapentin, but I feel if they're stable, that's absolutely fine for me. Dose wise we're looking for dogs 10 to 60 mg per kg every 8 to 12 hours, and cats slightly lower at 5 to 10 make per kg 8 to 12 hours, particularly if they have any renal disease, then we need to be looking at the lower dose of, of that megapa kick.

If you're trying to sedate a very fractious cat then higher doses are of course required, and we only give gabapentin orally. Potential side effects are sedation, ataxia, and the absorption is actually affected by antacid, so if your patient sits on them, then do dose them 2 hours apart. As I said, this is a really good drug for pre-operative care, and it's really good at max sparing, which is only a good thing in my opinion.

So there's lots of drugs available in practise that we use a lot, but we need to remember do not offer any form of analgesia such as ACP steroids, midazolam, diazepam, propofol, alfaxolone, Sivaflo, isoflo. Obviously we rely on a lot of these drugs, particularly the. Inhalants and the induction agents, but you need to remember they're just immobilising and causing muscle relaxant.

They're not actually offering any form of analgesia, they're just stopping your patient from telling you you're moving that it hurts, and, and the more we use of that, we know that the more negative side effects we have. I've added these guys in kind of under the drugs of maybe, are they good, maybe they aren't. I'm not a fan of either and we don't use them, but just in case this is all you have in clinic, and also to explain why we don't like them.

Tramadol is a weakm agonist, so we've established that being a weak mew isn't a good thing, only suitable for mild to moderate pain, and we've established that dental surgery is more than mild pain. It's really bitter tasting, particularly for cats, it's not an easy drug to give, and the side effects can be vomiting and dysphoria and sedation. Be careful in patients that are epileptic, and also be careful using this drug alongside trazodone, buprenorphine, fentanyl, or atriptyline, as you can cause serotonin syndrome.

Have a little research of that if you're unaware of that, and it can cause potential seizures which lead to death. We don't really use it, and personally I don't recommend it. Buttrophenol is sorry about the spelling there, is exactly the same.

I don't really recommend or use it. Yes, it's a very good sedative and it's very good if your patient has a cough. It's a very, very poor analgesic, but you may have just sedated your patient so heavily it can't tell you about the pain, but that doesn't mean that's appropriate.

It does work really well with the alpha 2 if you do just need to state your patient, how, so if you really are just going to take X-rays, I wake your patient up then it may be appropriate, but if you're planning on charting or scaling or polishing, I personally don't feel like that's OK. It's a new antagonist, so if you give this to them want to give methadone on top, it's actually gonna start reversing the effects of the methadone, so that's not going to work. So the gold standard of dental analgesia is of course local nerve blocks, the same for any surgery.

Local nerve blocks will stop the transmission of that pain, and that is the best way to prevent your patient having any form of of pain. They can be scary, for sure, and I can understand why people aren't giving them, and we definitely want to be trying to educate people more about how you can give them. We have a lecture coming up on local nerve blocks, so please email me directly if you'd like to be part of that, I can let you know.

Who can place these dental nerve blocks? Trained veterinary surgeons can, and trained veterinary nurses, certainly within the UK, but I know this can vary around the world, are allowed to place them with sufficient training and under the guidance of a registered veterinary surgeon, and local nerve blocks are often referred to as regional anaesthesia. So the main aims of local nerve blocks are to reduce the depth of anaesthesia and therefore control the pain as well after the procedure.

So we've kept them safer. We know the inhalants of the anaesthetic are the problem, and they will cause phassodilation and hypertension and bradycardia. So if we can reduce the dose that we need, then the side effects.

Also reduced, and also when they wake up, if they can't feel the area that you've performed surgery on, then, you know, there's very little pain that we need to be looking after after that. And bear in mind these do wear off, but you'll have a patient that wakes up very comfortable and hasn't gone through a stressful anaesthetic. You're also, as a team going to be less stressed because you would have had a much nicer anaesthetic experience.

So as we said, reducing the depth of anaesthesia is great, because it minimises the general complications that we see of general anaesthesia, as I said, such as hyperventilation, hypertension, and bradycardia. This is as scientific as I'm going to get with you today, and this is how the local blocks work. The nerve cells work by sending small electrical currents through adjacent nerve cells, and these currents are caused by the exchange of sodium potassium ions.

The local anaesthetics will work by blocking the channels that the sodium ions use to get into the nerve cell, so basically we're turning that current off. Therefore, no messages of pain can get through. I'm aware, I'm aware that's a very simplistic way of telling you, however, I think you can reach for many textbooks and articles and literature.

We'll give you the scientific version, but today we're looking at hands on knowledge that you can then apply and go, oh, OK, easy, that's how it works. So the benefits of local nerve blocks are that we're blocking the transmission of noxious stimuli before the incision. It's important that we're replacing these local nerve blocks before you start causing any pain, because remember we're blocking transmission.

So if we place a block and we wait the appropriate time and cause some pain. Those messages, as we said here, the current is cut off. No messages of pain can get through, however, if you cause a painful incision, those messages are already on the way to the brain, so if you try and block them, then those messages have gone, so it's easier to prevent those messages going off.

Their max bearing of up to 23% in one study, and it will give you a smoother anaesthesia. You're also gonna have a much better recovery, and this is what we call a true multimodal approach. And by using a local nerve block, you can reduce your drug doses for your opioids, for your post-op analgesia, and for your inhalant as well.

There's many papers out there. This one's a nice one which will tell you all about why it is such a good idea to be placing local nerve blocks. Of course with any procedure, everything we do, even taking the patient's temperature, placing an IV catheter, there's a risk, but we do it all the time because we know we need to, and we do what we can to mitigate those risks.

So for the risks of local nerve blocks, we could be damaging other tissues such as glow perforation, which would probably be one of the worst ones, or we could inadvertently numb the tongue. Cardiovascular effects will be seen if you've inadvertently administered the local anaesthetic drug into arteries or veins, and also we could have a hematoma form. You could cause damage, excuse me, to the neurovascular tissue, and you could of course like using any drug if you haven't calculated appropriately, you could cause an overdose.

But we can mitigate all of these risks, so training, obviously you wanted to learn more, so you're here, that's great. Practising on cadavers, know your anatomy, know your landmarks, and you can practise again once you've got to know your anatomy and landmarks and label all your drugs. So you're not giving them in the wrong place.

And make sure you calculate your dose for the overall dose for your patient and once that's drawn up, you know you can't have any more. So instead of thinking, oh, I gave, how much should I give here, how much should I give there, you don't have that. You've already calculated your overall dose, so you can't be tempted to give more.

And also be kind to yourself and have patience. Everything we've learned comes in stages and steps. You can't expect to just instantly get everything right in the first instance, which I know we'd all love to.

A lot of the profession are hard on themselves and perfectionists, and I understand that. We just take a moment to realise you're learning something new, which is going to be great for you and your team and your patient, but it just sometimes takes a bit of time. To make sure we're not giving this drug intravenously, we're always going to aspirate back and check there is no blood prior to administration.

If there is, you're gonna get a new needle and you're gonna try again. Consider the length of the canal for all your patients, so take your time, don't feel rushed, and keep a wide range of length and width needles for dentistry. So we have, 1/2 inch.

Length needles and 30 gauge needles, and then we go right up to larger needles such as 1.5 inches and a wider gauge. The most important thing, as well as having patience for yourself, is having patience for the time of onset for these drugs.

You can't expect to just give buppicaine and start cutting 5 minutes later. Like I said, the messages haven't been blocked off yet, they're all gonna get through. So, label drugs very, very important because if you give bupivicine, for example, intravascular, you could actually cause the death of your patient.

It doesn't have to be fancy fancy labels at the top, it can be handwritten blank labels at the bottom left, or if you really are just drawing it up, don't want to leave your patient, you can just use anything, paper, tape, and that's actually a thermometer cover that I've put over the the syringe. It's not ideal, but it's better than nothing in the moment. So there are lots of different nerve blocks, but the three that we're gonna discuss a little bit are nerve blocks of the infraorbital, maxillary and the interior alveola, which is also known as the mandibular.

We have a video here of Rachel Perry performing an inferior alveolar for an incisor removal of a patient who and she will talk you through how she's doing it. We don't have time within this webinar to show you all the ways of doing it, but we. I've got that in our webinar, so just email me if you want to join us.

It'd be lovely to have you. So let's play the right inferior alveolar nerve block to block the right mandible for extracting this second incisor too. It's got a complicated crown root fracture.

So I use an intraoral technique. My landmarks are the angular process of the mandible, which I'm gonna palpate with my left index finger. It's just behind that notch in the corner mandible, so here.

And then the last molar tooth, the 3rd molar tooth, and on a line that connects those two, roughly halfway along, on the inside of the mandible is our foramen, and we want to deposit the local anaesthetic at that foramen. So I open the mouth, get the ET tube and the tongue to the opposite side, approach from the opposite side to the one I'm blocking and that ensures that my noodle stays nice and close to the bone. They're just behind that molar tooth on the medial aspect of the mandible.

So he advanced the needle. Pointing it towards my index finger, when I'm at my estimated halfway point, I aspirate. If there's no blood in the syringe, I can slowly deposit.

The local anaesthetic, and I'm going about 0.1 of a mil, 0.15.

So you've seen Rachel placing a block that was what you might feel as a minimal procedure, one lower mandibular incisor. But it doesn't matter if it's one small incisor or a large carnasse, we should still be performing local nerve blocks. Sometimes it might not work, it might be because you've got a deformed skull on the patient, such as brachycephalic and teacup breeds.

If the patient's tissues in the mouth is inflamed or infected, it actually changes the pH which would change how well that drug will work. The oral, if there's any oral tumours in the mouth, it could obviously mess around with where the nerves are running and sort of make it anatomically quite difficult. The same with any recent trauma.

You may not have placed them correctly, and don't beat yourself up about that as long as we haven't caused any trauma, then that's OK. We don't always get things right the first time. So if it didn't work or I just can't place it because some anatomical difference, first thing, don't panic.

Also, please don't feel disheartened. You can do a local infiltration or splash block. They're not going to be that effective, but you could do that.

We've already discussed the benefits and how to give a ketamine bolut, or CRI. The same with fentanyl, so you can reach for one of those, which is what we do if our blocks aren't effective and even within the specialist. Hospital, it's not always effective, so don't beat yourself up.

The main thing is that you want to do them and that you're trying. Evaluate premedication given, when was it given? Do I need to give a bit more methadone perhaps, or is it due again or has my alpha 2 worn off?

And remember, we don't get things perfectly right every time. So what volume can I safely administer within the site. So cats and small dogs up to 6 kg, we say 0.1 mL per site, and then that increases in dogs 6 to 25 kgs, 0.3 to 0.6 mil per site, larger dogs 0.5 to 0.8 mL per site.

Remember that these meals cannot exceed the maximum mg per kg per patient, and this will vary depending on obviously the size of your patient, but also the drug that you choose. So your options are lidocaine, or two of your options we're gonna go through, one of them is lidocaine. The maximum total dose for your patient should be 2 me gig.

A really quick onset, which is why people quite like this one of 2 to 5 minutes. However, it doesn't last that long, so you need to be super careful with your post-operative, . Pain scoring and attention to your patients, so it will be more labour intensive in recovery and also if it only lasts 30 minutes and you've given full quadrant, lidocaine nerve blocks, you're not gonna get round the helm in 30 minutes.

So think about when you're placed in them. Potential side effects are CNS effects and of course a hematoma. We use the cane personally.

Rachel likes a lower maximum total dose for cats because some papers have reported that there's been toxicity at 1 mg gig, so we won't go higher than 0.75 mg per gig, but I do know of anaesthetists that are happy to go a little bit higher. With dogs it's 2 MB per gig.

Onset is 10 to 20 minutes, and duration can be 4 to 6 hours, and now anecdotally we've seen this last up to 12 hours, particularly in cats. So we really like this one, if you're planning your case correctly. And we just love that they wake up really comfortable, and it's much less labour intensive in the recovery period, we're not prodding them as much because they're less uncomfortable.

They don't have to have repeat injections of potential side effects of more opioids. Potential side effects of using buppivicaine is inadvertent intravascular. Injection will cause severe cardiac arrhythmias that are refractory, meaning they will not work to treatments.

They don't respond to treatment, which can lead to death. So please make sure that this drug is kept completely separate. I have a separate induction tray.

I have a separate premedication tray, and I have a separate local nerve block tray, and that little tray will be on the opposite side of the room, heavily labelled so that it's not inadvertently given. People ask me every time, can I mix adrenaline, can I mix buprenorphine? Can I mix n2?

Can I mix the two drugs together? There's no significant studies of any large proportion that have, shown that significantly proven that mixing two local nerve agents or adding in buprenorphine or an alpha 2, or indeed adrenaline have any outstanding benefits, but actually by mixing, buppivicaine and lidocaine, you're changing the pH so you're actually prolonging the onset and shortening the d. Which isn't ideal.

You also don't know how much exactly the kick you've given of each one to each patient. Adding in, alpha 2 or adrenaline that causes vasoconstrictions, so you may feel it's working better because you're keeping the drug in the area for that bit longer. And there's actually some really good receptors to buprenorphine in in the sort of bones and gum area, which is why that could work, but it's not something that we do or feel the need to do.

I'd love to see bigger studies of this done because it seems to be such a big subject, but at the minute, this is our personal current thinking. So is your patient still painful, you could consider a nerve block if you haven't done it. Topping up the analgesia, but only to a certain point, if you topped up the methadone, we're still not only better.

There's no point giving any more methadone, you're just gonna wake up with a dysphoric implanting patient, to try something different. Surgical technique may be out of your control if you're not the one doing the surgery, but a gentle and appropriate surgical technique with sharpened, up to-date and appropriately sized tools, trust me, makes all the difference. And let's think of this pain, or have I changed my premedications, and that's better for my patient, but I'm not used to the duration being shorter, so I need, do I need to top up an hour for tea?

Patient positioning can come into it if they're arthritic and a lot of our patients are older or they don't have much muscle mass, or maybe they just need a wee or they're trying to do a poop, that can all come across as being painful under anaesthesia. So just try and rule out the whole patient and remember it's not just about the face. They may have other problem areas.

You may know that they are, have a sore spine or sore hips, so we should be looking at supporting and cushioning them. So finally we're just gonna go over to cases that we've seen together, one's a cat and one's a dog. So this is a 6 year old neutered male domestic long hair, has gingivose dermatitis and requires multiple extractions.

His pre-op bloods were unremarkable. His clinical exam, apart from being a bit nervous, was clear, and he has had a reduced appetite. So I'm thinking in my head and then I'm writing some notes down about what I might be thinking we're gonna be doing, and then I take my case to the anaesthesia team.

So don't be afraid to do this, have a think, jot down some notes, you know, make a little mind graph of what you're thinking this patient might need. So I'm thinking, are they gonna need some antibiotics afterwards, if so, is my patient going to take this orally? With gingerface dermatitis, sometimes the inflammation can go down into the oesophagus, so we'll always give them aropotent, and there's lots of studies out there about Moropotin actually offering a little bit of analgesia.

Are we gonna have some ketamine, or going to use bivicine blocks? Are we going to use any IV antibiotics? Am I going to be going onto a CRI?

What am I going to send this patient home with? What has he had this morning? Would he take metacam?

Having all these thoughts in my head, so I'm putting them out there. We're making a precise plan, and we will tailor that to every patient. So for this guy, he was so uncomfortable, he said no to having an IV placed, which is fine.

He's had a little bit of gabapentin that morning, but not too much, and he still, wasn't happy with his leg being extended, which is fine. We don't like to push our patients at all, we won't do any form of heavy restraint, we'll go for chemical restraint instead. So this guy had methadone 0.2 MB per gig IM.

Meatomidine, we've gone for 10 mcg per kilo, because this is IM. Midazolam to add in a little bit more of a muscle relaxant there of 0.2 mg per kg IM so being really multi-modal.

And once he's got an IV we are going to give him that morepotin. So the IV's in, we're now ready to induce our patient and we're using propofol. Some, our anaesthetists prefer faxon cats, but I think it's all up to what you have, what you're comfortable with, and we're definitely going to do a coinduction because this mouth is so sore, it bleeds just by looking at it.

So we're adding in some ketamine because there's no co-existing disease that's gonna tell me not to, one Mg kick. We're gonna pop in 4 quadrantbpica nerve blocks as soon as possible. Make sure you clean the area before you're placing, so even if you're using a a hexainse little swab, to clean the the tissue area before you're placing your blocks.

So a patient on the left prior to extractions and then once the extractions have happened, and they're all sutured because if you're leaving patients unsutured, they're going to be painful. The sockets will get full of rubbish and get infected and it's sore and they won't you want to eat. So yes, you should be suturing your surgical extractions.

Here he is afterwards, looking much more chill about life. He's owner says that he won't eat metacam, and he also can't hold him to give him metacam. So we've gone for Onsure to try and hide it in food, because he seems to take tablets, OK, in food, and we're gonna continue his gabapentin.

You shouldn't stop gabapentin quickly anyway, and then we're also managing his care, not just in the drug wise, we're thinking of the whole patient. So anything hard going in his mouth is going to hurt, so soft food for 14 days. And then for our ginger dermatitis patients, we will see them back in 3 days, 10 days and 6 weeks.

And normally we would send them home with buprenorphine, trans mucosal or sublingual, alongside a non-steroidal and gabapentin. However, the owner just cannot handle him to do that, so unfortunately that wasn't an option, but it would be in the more handable caps. Number 2 is this gorgeous dog, 3 years of age, no coexisting disease, had a mandibular, carnassial extraction as it was fractured by him eating an antler, which we do not recommend.

Anything that they can dent, you, if you can't dent it with your thumbnail, it's too hard to go in their mouth, and then the owner needs to make the best benefit benefit for themselves as to whether they're going to allow them to have it. But unfortunately, he had one and this caused a fractured tooth, and a tooth root abscess, which is super painful. He was a nice friendly guy, so he had methadone 0.2 megig into his, catheter, so IV meatomidine much lower because it's IV 3 mcg per kilo, a propofol induction.

We knew that it was more of a singular area and not so much inflammation and that we were gonna get the block on board ASAP so we didn't feel the need for any ketamine at this point. We did place an inferior alveolar, also known as a mandibular nerve block of bpivicaine. And we did give him paracetamol, 15mgbiic IV during the surgery, and then after surgery he had Metacam.2 Mgbaic subcup.

He went home to continue some Meacam once a day and paracetamol 10mg BID for 3 days, and again, soft food for 14 days, and more so for our dogs who are out and about, maybe off the lead, just make sure they're not known to pick things up if they are, maybe they need a basket muzzle for a week or so, and not to encourage any playing with rope toys or picking up any hard items or chew toys or pebbles or if they love to chew on sticks and things like that. That will rip through the stitches that you've placed and that will be painful, so again it's not just about the drugs, it's about what to do to prevent any further pain. Post-op care within the hospital, we should definitely be pain scoring them before they go home and into recovery and that will depend how often as to what drugs you gave them and also what local nerve blocks you're using.

Offering them some warm, soft food, nothing hard to eat, chew, or to carry, and also recovering in a warm, calm, quiet environment. If you're cold, you're gonna shiver, that's painful if you have any areas of of any inflammation or surgery. It's particularly if you haven't used any local nerve blocks and they're shivering, it's actually really uncomfortable.

And if you just wake up somewhere and you're feeling scared, it just exacerbates every other feeling you may have such as pain. So it's about treating the whole inpatient and the environment appropriately. Again, I cannot explain how using pain scoring will really really help when there's multiple ones out there.

Sometimes they do need extra drugs and sometimes they just need some love. This little guy with a feeding tube and had a fractured jaw on the left. He was more comfortable with having a cuddle.

That's how he lived his life at home. He didn't like being in the cage, he didn't like hospital life, so for him, he was comfortable and happiest when the. Had a cuddle and the gorgeous one in the middle, he was used to being on the sofa and having duvet days, so that's what we supplied for him in his recovery.

And he was quite happy to stay there until it was time to go home. So sometimes they do need more drugs, but sometimes they just need a little bit of our time and some love and some creature comforts. So don't forget that.

Make sure that the owner is aware that you've done a really good job in the hospital, you know, you've learned how to do blocks, you've been multimodal, you've had a lovely anaesthetic, the blood pressure was fine, your patient's so comfortable, you've pain scored and kept an eye on everything. The owner now needs to take this on at home, so make sure that that medication guidance is very clear. This will help with the correct care and calm the owner.

Tell them when to start the medication, what each medication will do, because I used to find a lot of people when we did our post-op phone calls were like, oh yeah, I didn't need the Medicare, and you seemed fine. If you explain it's gonna help with the inflammation, like when you cut your arm and you just get that horrible heavy burning feeling and it stops that, they're more likely to give it when they understand what it does and show them how to give each one, particularly, physically show them with something like Metacam. This is where you go on the syringe.

We've all seen the patient that's had a syringe full or 10 syringes full of Metacam instead of the 10 kg mark and explained to them to only use that syringe. And follow up where you can, and this doesn't need to be a medical person. Anyone in the admin team can call and say, hi, how's Mr.

Sparkles feeling after his dental extractions yesterday? Is he eating OK? Has he had any vomiting?

Have you any questions and have you been given your medication? And I find that really helps and clients really like it. And I also like to know how our patients are doing, and it stops any potential postoperative issues such as, oh, I haven't eaten for 5 days, but I didn't feel I had to tell you.

Oh yeah, no, he looked a bit uncomfortable, but I didn't give the drugs and. You know, or they've picked up something hard and they've now got a bit of an infection, I feel like it just stops. Future potential heavy workloads.

Thank you very much for having me. All of our, items that we currently have, such as Caography guides and patient warming kits, are all on my Etsy store in memory of my cat Bertie under Bertie's boutique, and we will be having lots of poster guides, local anaesthetic guides, ECG posters, hypertension, and, next year we'll be releasing a dental pocket Bible. So if you're interested, have a look, and if you would like to be on the waitlist for any of our coming soon items, then we have, some waitlists going on as well.

So thank you to the webinar vet, and thank you to you for listening. As I said, there's anything I haven't been clear about, you want to know more about, or you have something interesting you want to chat about, then you can contact me in any other ways on there. I hope you've taken a couple of things away from this lecture that you can instantly apply to feel better and to help the standard of care for your patients.

So thank you very, very much for having me.