So hi everyone, thank you so much for joining me, and choosing this webinar. We do have to anaesthetize a large amount of geriatric patients, and I know it's something that used to make me feel quite anxious. So I'm hopeful that by the end of this webinar, you'll be feeling much more comfortable about your options and can take some talking points back into practise as well.
So as you can see, the title of this webinar is managing anaesthesia for the geriatric Patient. My name's Stacey Parker. I work at Perry Referrals, which is a dental referral specialist company.
And we work out of North Down specialist referrals at the moment, and we occasionally go off to Marwell Zoo and treat some of the animals there. So it's a little bit strange sometimes on webinars if you haven't met me. I think it's nice to put a face to a name.
I'm the one on the right at the front with the sort of burgundy scrubs, and that's my boss behind me, Rachel Perry. So I qualified as a veterinary nurse in 2014. I then did my feline nursing certificate, which I really enjoyed, and then my EA in anaesthesia and dentistry.
I'm now starting this year my EA in advanced anaesthesia. My official job title, if you like, is a referral, anaesthesia and dental nurse, and I also provide in-house and external CPD such as this, and we also supply learning aids and patient warming packs. You can get in contact with me, if you'd like to, if there's any questions that come up from this webinar, then feel free obviously to contact the webinar vet, or you're very welcome to contact me directly on those details.
As I said, these are the two companies that I am attached to. And thank you again for having me. So let's get started.
So our learning objectives for today is to understand the physiologic and anatomic differences in our geriatric patients opposed to our healthy younger patients, and we also need to look at understanding common coexisting disease processes that are more likely in our geriatric patients. We'll cover the per anaesthesia anaesthesia considerations together, and I hope that you'll leave this webinar feeling confident that you can create an appropriate anaesthesia plan within your team for your geriatric patients. We're also going to discuss how commonly used drugs used in practise could affect our geriatric patients and how we may want to tweak how we use them.
So our geriatric patients can come in looking a little bit geriatric, I suppose, like there's some beautiful lady on the bottom left, or they might just look a kind of bit middle aged and you might be really surprised. So we mustn't judge a book by its cover, and it's the same with dogs. They often get that grey muzzle and you can appreciate their age, perhaps, but sometimes in some breeds, they really don't slow down and you just wouldn't know by looking at them.
So it's really good that we have a look at their age, make sure that's correct on the system. So we talk about geriatric patients, but what does that mean? And why does this even matter that they fall into this category?
So a geriatric patient is defined as a patient that has reached 75% of their average life expectancy. Now that is going to vary between species and breeds, which is why we haven't just said, right, 1/10 is geriatric, or 1/7. It does vary between species and breeds.
And old age isn't a disease in itself, and as a referral clinic, we do get a lot of geriatric patients sent over to us because the primary clinic, or perhaps the owner isn't happy having the anaesthesia performed there. And you know, if you feel it's not within your remit to do that, or they have too many coexisting diseases, and that's perfectly appropriate. What's such a shame is when you see that some owners and some veterinary practises are just too scared to anaesthetize these patients and say, no, no, no, no, don't, don't treat that because they're too old.
And it really is about quality of life. So I think if we can become confident and comfortable managing these geriatric anesthesias, then we can prolong their life but keep the quality as well. Although it's not a disease in itself, old age patients are more likely to have a hidden underlying disease process, and we'll talk about what those might be later.
We're not going to be able to talk about the ins and outs of every single disease process, that would be another couple of webinars in itself, but just to give you an eye, it's what you need to be keeping an eye out for, really. And it may only show its face this underlying disease when you challenge the body by anaesthesia. So it's about really being to catch these things before they become a problem and being aware of what might occur.
Therefore, every patient should be evaluated individually, and age-related physiological changes should be evaluated carefully prior to agreeing to any anaesthesia. And the reason we need to make an individual assessment is we can then talk through the risk benefit one on one with the owner and every patient and every owner and every situation will be very different. So we'll start with the main thing that I think we worry about and in the top of our brain when we think of our older patients is those cardiovascular differences.
You know, that's the one system that we really, really don't want to be upsetting. Now, our older patients do have a decrease in functional cardiac reserve, and this means they can't cope as well with cardiovascular changes that could be caused by stress, anaesthesia, analgesia or sedative drugs, and we obviously have to use all of those drugs, and there is an element of stress coming into the hospital. So having a reduced cardiac output and contractility, a decreased blood volume and a decreased blood pressure, and a decreased ability to auto regulate blood flow and maintain blood pressure will all contribute to a reduction in cardiac reserve.
And those 4 points next to that arrow are all relating to our geriatric patients. That will be what's happening with their cardiovascular process. And this is really important to bear in mind as they may need more blood pressure support, and they may need that from quite early on during the anaesthetic episodes.
So we need to be prepared that our monitoring is on and ready to go from the very beginning, and that we have everything we might need to support or make any changes to their cardiovascular system. It can also cause an increased circulation time, which is an increase in what we like to call an arm to brain time, meaning that we inject those drugs normally into one of their legs into the catheter to make them go to sleep for the anaesthetic or sedate them. And those drugs can take longer to take effect, so the time it goes from the catheter of you injecting to their brain can actually take a little bit longer because of their difference in their cardiovascular system.
Therefore, it's actually a lot easier to overdose our geriatric patients because you may have given your propofol at the usual speed. Hopefully, that's not too fast, but even at your usual slow speed, you may then think, my goodness, this isn't having any effects. And perhaps you didn't use an alpha 2 because they're geriatric, and you just think, oh, that's why I didn't give them a heavy pre-med.
But actually it could just be that their circulation time is that bit longer. So we must be really careful not to inadvertently overdose our geriatric patients by a administering drugs too quickly. And I do actually have a video of the speed at which our anaesthesia team inject propofol in our patients.
So we'll play that now. There isn't any sound on the video. So our patient has already been pre-medicated and is having free oxygenation, and that's something we recommend for every single patient, particularly our geriatric patients.
The catheter's just been flushed with some saline there, and the patient is already wearing a jacket. It's on a nice fleecy bed and it's got a blanket on. The ECG is also already attached and if it wasn't a black cat, I would have the SPO2 probe on a toe or an ear as well.
So this is the propofol, as you can see, making sure there's no bubbles, you can see the ECGs there in the background. We're not overhandling the cat. These cats are normally quite arthritic.
They don't wish to be pulled about. And we really need is feeling the pulse there. So far they've had 0.2 mL of propofol.
That's a 4 kg cat and that's 0.4 mLs of propofol altogether. That's 0.5.
So we'll stop, he's gonna have a look if he's happy that he's given enough of an induction agent, there's no how people blink there. So you can see we really do give our propofol or if we use alfaxolone, that's perfectly appropriate to very, very, very slowly into effect. So if you can slow down how quickly you're getting your induction agents, especially with your geriatric patients, you should find that you don't need as much and therefore you won't have such cardiovascular effects from it.
Ale is on the hypotension. And hypertension under anaesthesia is classed as a mean below 60, although I don't like it to drop below 70 millimetres of mercury, and a systolic below 100. And it's so important to maintain their blood pressure.
If the main is allowed to be below 60 or the systolic below 90 for more than 15 minutes, we will. Be seeing reduced tissue perfusion and the accumulation of lactic acid, which will cause acidosis. We can damage the kidneys and this might not be seen immediately.
They may come back a few months later with chronic kidney disease and that may have been caused by an anaesthesia episode, or we should see worsening of chronic renal failure. Severe hypertension will provide reduced coronary blood flow, and this will cause arrhythmias and could lead to cardiac arrest. And also hypotension, so low blood pressure, can be the cause of a prolonged recovery, which can lead them to death.
In order to safely treat hypertension, we must first understand what is causing it, and we all really want a one stop fix of the hypotensive, what should I do? And unfortunately it just doesn't work like that. We need to understand why they're hypotensive in order to correct that.
The incorrect treatment could cause more harm than good, and I think we're very used to just giving them a bolus or we're then upping their infusion rates, but perhaps it isn't what they need. So if they've had fluids lost, we may need to correct that. Dehydration should be corrected ideally prior to anaesthesia, but obviously that can't happen in emergency or urgent situations.
If they have a low heart rate, they're gonna need an anticholinenogenic, such as glyco or atropine. No amount of fluid for a bradycardia-induced hypertension is going to correct that. You will just cause more damage and overload that heart.
Think about what drugs you've given, could they have caused hypertension? Did I use a high dose of ACP? Are they cold?
Your patient can be more hypertensive if they're cold, and we should be preventing hypothermia rather than just treating it. That's something we'll cover a little bit later together. Are they too deep under the anaesthesia?
Do you have the inhalant on too high? Did you give too much propofol? Did you give it too quickly?
And do they have a reduced cardiac output? And is that because of the drugs you've given, or do they have a coexisting cardiac disease process going on that you did or didn't know about? So cardiovascular differences with our patients, they can be chronic or degenerative valbular disease is much more likely in our geriatric patients in comparison to our younger patients.
They're more susceptible to arrhythmias. Therefore, we should be avoiding or using very low doses of drugs that may change the heart rate either up or down substantially, such as ketamine or alpha 2s. We won't be able to go through every single drug that you may be reaching for within your clinic, but I have chosen three of the most popular ones that we may be reaching for with our geriatrics, and we will cover them together later on in this webinar.
The respiratory differences in our geriatric patients, there'll be reduced thoracic wall compliance and decreased lung elasticity, and there could be atrophy of the intercostal muscles, and that's because they're a little bit older, they're not gonna have as strong muscles. The lungs are gonna do that. Thoracic wall compliment.
All of those effects contribute to a decreased respiratory reserve, which means that our elderly patients are more susceptible to hypoxia and hypercapnia when placed under anaesthesia. So we must be aware of that. So make sure we keep them safe, regardless of the fact that those things are happening.
We must monitor the catography and the oxygen saturation very carefully from as early on as possible and into their recovery, and we must immediately investigate any abnormalities. We should never place anything on their chests, such as a really heavy blanket or a clipboard or the blood pressure machine or an elbow or any instruments from surgery. When you think about positioning, they may not do as well on their back, they may not do as well on one side to the other.
We must be prepared that they may need IPPV, so breathing for them, or they may need mechanical ventilation. But we must be careful if we're performing IPPV because remember those lungs are a little bit stiff and not as elastic as our younger ones. They may not have such a high tidal volume that they need.
And the same with mechanical ventilation, we'd usually go a higher restrate with a smaller volume. So as soon as you've given any medication, we must watch them closely to see if they're struggling at all with their respiratory effort. And we should be pre-oxygenating all of our patients no matter what their age, as long as it doesn't cause any extra stress, but particularly with our geriatric patients.
We should have everything ready for intubation, it should be right there at hand. And same as pre-op, post-operatively, those drugs will still be in the system. They may be raising their head, they may be excubated.
But this is why this is the most dangerous part of the anaesthesia process. When they did the big sepsis study quite a while ago, but I feel it's still current. They found that in recovery was the highest chance of death, and that's because we've gone from having all that close monitoring on.
They're taking it off and they may not be having that one on one monitoring, but the drugs are still in their system and they can go back to being very, very sleepy, particularly our geriatric patients. They may put themselves in a position that compromises their airway. We'll move on to the hepatic and renal differences with our geriatric patients, and both the hepatic and renal mass can be reduced in our elderly patients.
And this is likely secondary to decrease in the cardiac output as we covered earlier. And this means that they have less functional organ reserve causing a decreased drug metabolism and clearance. So drugs may therefore not need to be repeated as often.
Perhaps you're used to having to give your methadone every 4 hours on the dot. They may not need that as often. Always assess them, administer any drugs slowly into effect, and start at a lower dose.
We can always add in more drugs. It's much easier to do that than to remove them. And I would also recommend that we avoid drugs that cannot be reversed easily or that are particularly long lasting.
So focusing on the renal differences to start hypoxia and hypertension and hypovolemia can all exacerbate an already reduced renal blood flow and must be avoided. And we should be looking to avoid that in all of our patients anyway. We just need to be hyper-aware with our geriatric patients.
And this is due to the decrease in reserve, our elderly patients will have less tolerance for excessive fluid administration, so we need to be careful how much fluid we're giving them. Hypovolemia, hypertension, dehydration, and blood loss. And again, we should be looking to avoid that in all of our patients.
So if we have these 5 concerns, then let's have a look at 5 ways to avoid or treat those concerns. So we don't want to give them excessive fluid administration, so we should be using judi judicious fluid therapy doses. 3 mL per kg per hour is what we use in our otherwise healthy cats, 4 to 5 mL per kg per hour in dogs.
Also be quite careful with the amount of flush you're using in small dogs and cats as that can really add up and that's your intravenous flush. They're hypovolemic, we need to replace lost fluids over time preoperatively where possible. If they're hypotensive, we want to try and avoid that to start, but if we do fall into that hypotension sort of situation, then we can use appropriate drug and maintenance protocols to correct that.
You should be assessing hydration preoperatively and we can start in interviewing this fluid therapy overnight in the appropriate cases, of course, when it's not in an emergency. And be prepared to replace blood loss with blood products if significant blood loss is deemed a risk or is likely to be expected, then we should have it on hand and have them blood typed. With regards to our hepatic differences, a reduced hepatic function can cause impaired clotting function, hyperproteinemia, hypoglycemia or hypothermia.
Again, let's talk how we can try and avoid those. If we have established those concerns with the liver, then we can run further tests. Do we need to run clotting factors, and do we need to do a BMBT test?
With the hyperproteinemia, we could be replacing proteins if required, and again, that's why we would recommend for our geriatric patients that they've had a full blood profile in the last month or so prior to anaesthesia. We like to have a haematology and a full biochemistry and perhaps a PCV total solids and definitely electrolytes as well. Hypoglycemia, we should be checking our blood glucose preoperatively and during the surgery and postoperatively for our geriatric patients, and perhaps they don't need such a long starvation period, 4 to 6 hours after a small meal of wet food is OK.
Supplement that that hypoglycemia if it occurs, and that's best to be done intravenously. Hypothermia should be avoided where at all possible. It's much better than having to treat it.
We can treat it, but it's so much easier if we can avoid it happening. I agree it's very difficult in some cases, particularly for abdominal surgery where there's a lot of fur removed, the skin's being cleaned so it's. Damp and then we're opening the abdominal cavity, usually flushing it out.
The theatre is probably quite cold. It's a lengthy procedure. They may have started off cold.
So I agree that sometimes it's quite difficult, but if we can do everything we can to prevent them getting too hypothermic, at least, it will be easier. Ways of keeping our patients warm. Obviously I work predominantly in dentistry, so some of these will reflect that, but you can use a lot of these options for other surgeries.
So for dentistry, we will use a kennel liner such as what my colleague is holding there on the left, and the hole will be cut with the the face of the muzzle, and then the muzzle will be placed through that hole, and any water used for the oral surgery will be collected by that kennel liner or puppy pad or whatever you want to call them, and not going on the patient's face. You can use the forced warm air blankets and you can get reusable covers now that go through the wash. They're a lot more environmentally friendly.
Nice blankets, fleecy blankets are good, they're not too heavy on the chest, and they're also gonna provide really good insulation and you can layer them up. You can see how that kennel liner is working there to absorb that blood and fluid. Smaller patients can be placed into nice snuggly beds, you can sit them into those.
You can use a heat moisture exchange on the top right, the green disc on the Labrador there between the ET tube and the breathing circuit. And all of our patients have fleece jackets and padded jackets, and socks, and then they're placed on. A warmer, not a warm buster bed, but the buster bed will collect their warmth and stop it just evaporating and keep them nice and toasty.
And obviously we would place a bear hugger and then a blanket over them as well, but that's just so you can see, what we do. I appreciate that you can't wear a jacket for all types of surgeries, but perhaps they could be wearing one preoperatively to get warm postoperatively and particularly for CTs and MRIs where the rooms are normally kept quite cold and so that the machines are happy working. So baby socks are great, you can always try baby growth.
They're the buster beds that we have that just stop all the, the warmth from leaving their body as quickly. And if you're doing oral surgery, then you also need an absorbent mat over there under their head so the fluid isn't accumulating either. And these are lots of different guys wearing all the different types of jackets that we have and we find that we keep them nice and warm and it's tolerated really well by our patients.
So let me know if you'd like to look into those. Yeah, very cute. When we're looking at keeping our patients warm, we need to be careful though.
We can cause harm by keeping them too hot. Hypothermia does kill, but also we can cause burns depending on what we're using. So I don't like hot hands.
I feel like that's when there's, you put warm water in gloves. You could burn yourself quite easily by creating them. You could burn your patient, but equally they get cold quite quickly, and then I feel like they just take the warmth away from your patient and make your patient cold.
You mustn't use the forced warm air blanket machine without a suitable cover as you can cause thermal burns. And as I discussed earlier, using heavy blankets on smaller patients, particularly when they're geriatric, will actually make it quite difficult for them to breathe. I don't like the hot microwavable discs on unconscious patients because they can get hotspots.
And heat pads, we don't use them on patients over 5 kg. And when I do use them, I have the heat pad and then a thick wet bed, and then I have the buster bed, and then the patients in a jacket. So there's 3 layers between the two.
Because I have seen patients get burnt, particularly heavy patients with abdominal surgery where a lot of water is used, so we must be really careful. And we should be replacing them and checking that they're working well with no hotspots if we are using them. You can also use the hot sort of circulating water blankets, but you really must follow the manufacturer's guidelines.
The patient must be in contact with the sensor. We shouldn't be using the top level of the heating, and they do need to have parts replaced quite regularly. Other ways of keeping patients warm that I haven't mentioned, sort of bubble wrap, the fluid warmers as well, but they must be placed near the IV catheter, otherwise, the fluids will be cold by the time they get down there.
And I know there's lots of other imaginative ways that people do keep their patients warm. So let's move on to the nervous system differences that we might see in our geriatric patients. They're likely going to have an altered sensory motor, cognitive and autonomic function, and they may have reduced cerebral perfusion, which potentially is then causing enhanced effects to anaesthesia drugs.
So we just need to bear that in mind, and that's another reason we may use lower doses for some of our drugs, so we don't see such extreme reactions. And this all boils down to the fact they're also going to be a little bit senile, bless them, that's sort of the less fancy way of saying nervous system differences, and that's something we'll cover in more detail shortly together as well. The patient is quite likely to be on more medication than a healthy younger patient.
I mean, there may be a healthy geriatric patient, but they may be healthy because they're being kept on some sort of medication, just like humans, I think my nan's on the multitude of drugs and I feel like her geriatric patients are more likely to be too. Therefore, it really is imperative to investigate what medication the pet is on, when they last had it, how often they have it, how stable their condition is, when are they next do it if they're due to stay in the hospital. And this is where our pre pre-planning really comes into play.
We should be reading their histories prior to their admit into the hospital, and ideally, if it's a planned procedure, kind of the week before in case any drug protocols need to be tweaked, such as if they're diabetic when they need particular heart medications that we may need them to be weaned off on. And this gives us time to really collaborate with the vet that be doing the case and the owner to make sure that we're doing the best thing. You know, if they're having afternoon surgery, they should probably have a light breakfast.
And I think the better we can we can tailor, our anaesthesia plans for our geriatric patients, the more the owner feels included, there's less stress and it's more likely to run a little bit more smoothly. And I understand that's not ideal in a very busy practise as well. It can be difficult to schedule that in.
And equally if they're having surgery that you just didn't see coming, then you're not gonna be able to be as prepared. So let's cover some of the common pre-existing conditions that our patients may have, but remember you may read through that 100 page of history and not see anything about it. But perhaps that just hasn't been diagnosed yet.
Cats in particular are very good at hiding what may or may not be going on. Dogs can too, so just remember we really need to try and move between the lines as well. So some of the common preexisting conditions that are definitely going to be more likely in our geriatric patients are chronic renal disease or acute renal disease, hyperthyroidism, Cushing's, Addison's, diabetes, cardiac disease, hypertension, hypotension, it could be quite senile, and then.
Most likely going to be struggling with some form of arthritis as well. Now, this list is not exhaustive. I, completely admit that.
But these are the most, some of the most common conditions that we may see, and we should be aware of them because it will change how their body is going to cope with the anaesthesia, how you treat them, how you might rescue them in a difficult situation. And also the owner then has a really informed consensual conversation with you about the risks of what we may be doing and the benefits of doing so, and what we're doing to mitigate those risks. So we're going to focus on the most what we might call common.
I feel like most patients over into the geriatric age, will be having likely some sort of cardiac disease or their heart, you know, is just that bit older, it's been working quite hard for a long time. They're likely going to be senile, and I do think all of our geriatric patients will be arthritic. So we did touch a little bit on cardiac disease and more sort of the physiologic part of it earlier.
So the more practicality side is we would recommend that an echo is offered for any heart murmur that is heard or an arrhythmia that is noted. And we would inquire with all patients, cats and dogs, that's any change in their exercise tolerance, any changes or coughing, and we'd be asking this regardless if we heard an echo or if they had a preexisting heart disease that we already knew about. We would delay any non-urgent surgery to allow a workup if the owner is wanting that workup.
This is why we would look into it sort of the week before if I'm reading a history and seeing that a heart murmur's been noted, but an echo hasn't been offered, then I will be calling the owner and suggesting that we squeeze an echo in prior to any surgery if it's optional. If that echo or work up for cardio is declined, make sure the owner is aware that there is an increased risk. We can treat all patients if they do have a disease process, but different cardiac diseases will need different treatment, different rescue, different drugs to be avoided or used under anaesthesia.
And so you're working a little bit in the dark if the owner doesn't wish to have an echo. That's their decision, and it might be frustrating, but it is their decision, and there may be different reasons why they're declining that. But we just have to make sure they're aware that it was an option and if they don't want it, and it does increase the risk a little.
If we're worried about cardiac disease, then we do need to keep the stress levels down as much as possible. And if they do have an ongoing cardiac disease, just make sure that you have a recent enough echo so you have a recent idea of what's going on with that heart. The same as if you had a renal patient, you'd be looking for recent bloods.
It's the same with the cardiac disease as well. In cure all medications given normally leading up to surgery. There are a few exceptions to this rule, as always with veterinary and anaesthesia.
So if you're giving them clobugel due to the risk of clotting, always consult your cardiologist if you're not sure, as there are beliefs that we should perhaps be stopping that for a few days leading up to elective surgery, as we don't want the patient to bleed out, or we might need to give them different medications so that we can handle their situation a little bit better. We should be paroxinating all patients, as I said several times, but particularly if you're aware they have cardiac disease, and we should be using medication and doses that will keep the heart rate around the same. We don't like these big swings of change of heart, heart rate for our cardiac patients.
They don't cope well with that. We want the stress free induction, as you saw with the video earlier. We also want the stress free recovery, and that would include very close post-op monitoring.
We will be careful with the use of intravenous fluid therapy. We do not want to push that heart over the edge if we give them too much fluid, and we'll be using very careful drug selection, depending on the type of cardiac disease present, which is why, as I said, ideally we will have that echo. A lot of our patients will be quite senile, especially as they get that little bit older.
They're spending more time at home. They like their routine. They get up, they have breakfast, they go for a walk, then they have a little toilet trip, and then they sleep and they probably have a favourite spot that smells what they like, they get the sunshine, and that's their day.
They don't like being removed from it. And I always give our patients, owners, the heads up of geriatric patients that it probably will take a couple of days for your pet to feel comfortable and completely settled at home. And they often worried that they've gone home painful, but we've covered that with analgesia.
But it is just that they had a really odd day out that they didn't understand was coming because we can't verbally talk to them in such a fashion, and they just didn't understand. It totally threw them off. And I think that can be seems quite normal for our geriatric patients.
So if we can do everything we can to reduce the level of stress when they do come to us, they can go home feeling a bit more settled and get back into their routine as soon as possible. So therefore, we'd recommend to recommend the amount of time they spend in the hospital. Not always possible for our very poorly patients who undergo big anesthesias and surgeries, but something to bear in mind if we can.
A nice padded kennel so they don't harm themselves and it's good for their arthritis, calm and quiet environment, perhaps some gentle soothing classical music, having the hormone and calming diffuses and sprays around and items that smell of home, going nice and slow. Remember they may not see or hear well. Medicate them to help reduce stress levels where needed and allow long times of rest between medication if you can once they've finished the anaesthesia they're in the hospital.
And if they have a routine at home, find out what that is and see if you can keep as close to it as possible. You may wonder why I'm talking about this when this is an anaesthesia webinar, but they all need to have that kind of holistic approach. If I've got a patient that comes for anaesthesia and they've been kept out of routine, they've been uncomfortable in their kennel, it's been loud and stressful, they haven't been handled with much patience or care, they're gonna be incredibly stressed.
And an incredibly stressed patient is not something we need for anaesthesia. It's going to give us a rocky road for us, the surgeon and for the patient, they're gonna wake up stressed. The recovery will be longer, their healing will be longer.
They're more likely to have issues under anaesthesia, and that's why we need to think about the whole project, not just the fact that they're having this drug. We're gonna do this surgery, and then we're gonna wake them up. It's a whole picture that we need to be looking at, so it is why I've added these points in.
Again, if they're arthritic, we should be having them on thick mattresses in theatres and in prep rooms and in their kennel. Nice thick bedding that's also nice and soft and absorbent. And once they're awake, I like to give them a pillow to sleep on, and they're probably used to doing that at home or finding sort of the arm of the sofa to sleep on, or those dog beds have normally got sort of the outside rim is higher, so they like to sleep how they're most comfortable.
With regards to being under anaesthesia, they're obviously limp once they're asleep, so we must be very careful how we handle and move them. Ideally they should be moved about on trolleys and not just in your arms, and think about positioning of their limbs during surgery. Do you really need to hyperextend it as much as you are?
Do they need to be crossed over? Sometimes, yes, they do. Other times, do they need to be just as much?
Think about how sore they could be when they wake up. And think about this in your analgesia plan, not just about the surgery that's being performed, but have you put them in a position for a long time that could be uncomfortable? Do they need a little bit of physio afterwards?
Do we need some post-op analgesia to cover that exacerbation of any arthritic pain they may have? Gentle handling, careful when moving we've covered, and pre-operative analgesia prior to handling. These guys may not want to have an IV placed right away.
They may be quite sore and just need to have that uncomfortable edge taken off and reduce the stress with an iron pre-mer prior to placing a catheter. Another way we find works really well is using a hind limb intravenous catheter. They don't tend to mind that as much.
It does take a little bit more skill and practise, so I offer more practise with my patients under anaesthesia already, that look like they've got a good vein and then that gives me more confidence that we can then try it with our arthritic older patients, and they do tend to tolerate that quite nicely. If you're arthritic and you shiver, that's gonna be painful. So you need to keep them warm and avoid hypothermia, as we mentioned.
And a lot of studies have shown that 60 to 90% of cats do have arthritis, and that number is gonna be in the higher quadrant when we look at our geriatric patients. We must weigh our geriatric patients on the day of surgery. The weight can fluctuate quite quickly.
Particularly if they're poorly, and you're having to do sort of emergency surgery or, you know, just dentistry perhaps where not just dentistry, but dentistry where you know they're coming in but they haven't been eating as well and you know weighed them last week, but we should be wearing them on the morning of surgery. We should be taking their blood pressure preoperatively, knowing what it is preoperatively will help guide you as to what to expect during the surgery and you've got that baseline as well. So we'll talk about some medications now, and do you change your dose of pre-medication or your induction agents when you have a geriatric patient?
I know some clinics that I've been to and help teach have a chart on the wall, and a 5 kg cat or a 10 kg dog may have such and such of a sedative, such and such of a. Analgesia, and that's done by a chart on the wall, and then they say, oh, it's geriatric, so instead of being a 10 kg dog, we'll just drop everything to be an 8 kg dog. And it's good that you're starting to think of reducing doses, but we need to have a look further into that.
We're now reducing potentially the analgesia, which they're probably going to need. We should be making individual plans, particularly for our geriatric patients, not just of a chart. Do you know what Mpag that chart says on your standard cases, and do you understand the potential side effects of each drug on that chart?
And do you know the benefit of each drug on that chart? And this is where research and education is key. And never ever be afraid to ask questions and advocate for your patients.
When I was first starting as a student, I had no idea what ACP and TAub were. I had no idea that if you just reduced it from a 10 kg to an 8 kg dose that I'd be reducing my pain relief. I didn't know what ACP did.
I didn't know what Torcuic did. I didn't know that there were better analgesias out there. I didn't know the side effects of hypertension and hypothermia and the prolonged sedation that you may see from ACP.
And we need to ask these questions and help educate one another, so when we're training our new nurses, we say this is the drugs we use and this is what this one does, and this is what this one does, and this is what we need to look out for. And then we have a better idea as to what drugs we're using as to what drugs we might need to tweak or change for specific cases, and in this case for our geriatric patients. We need to be really careful with our drug doses.
Use drugs that you can titrate, and it's better to start a little lower and add more and if needed, especially with regards to our sedative drugs. Think multimodal. Smaller volumes of several appropriate drugs will carry less side effects and will work quite nicely together as well.
As I said, ensure you have a current patient weight from that day. We're going to cover 3 drugs which I find a reach for quite often, opioids and benzodiazepines for our geriatric patients, and alpha 2 agonist, which I think are used quite a lot in patients, and sometimes avoided quite a lot in patients because we're scared. So I thought I'd cover those three, and we'd talk about ACP very, very briefly.
It's not something I reach for very often in my geriatric patients. So opioids provide analgesia. In our geriatric patients, they also provide a degree of sedation.
There can be some respiratory depression, so we must always keep an eye on them closely once it's been administered. They are metabolised by the liver, so we should be using lower doses and we shouldn't need to dose them as frequently if we know from their blood work and their history that they may have issues with their liver. We would recommend using the full new opioids for painful procedures, such as methadone, but the form you may have a higher degree of respiratory depression, but we've already said we're gonna keep a close eye on them once it's been administered.
The full view is also more likely to have a side effect of bradycardia, but like we said, we've educated ourselves. We know that could happen. That's not a surprise.
We were monitoring our patient, we're aware it's happening. So we may use a lower dose if we're worried it's gonna happen. We can use a titratable CRI or you know, varied rate infusion, and or we could be adding in anticonnogenic to counteract the bradycardia if it's having a physiological effect such as bradycardia-induced hypertension.
I don't mean that you give an anti-chologenic as part of a pre-med. That's sort of an old wise term and not recommended anymore. What we do recommend is having it calculated and having the drug close to you.
And then if you do find that your patient becomes bradycardia and that is causing hypertension, you can have it with you and you can treat them. We like to use glycopromium, 5 to 10 mcg per kilo IV, we can repeat, the 5 again. If the original 5 mcg per kilo IV hasn't been effective.
I find that's a little bit more gentle than the atropine, so the glyco would increase the heart rate, which will bring your blood pressure back up. Takes a little bit longer to work than the atropine, as in it takes about 60 seconds opposed to 10 seconds, but it is. Longer acting, and it doesn't cause the eyes to be dilated postoperatively and be extra light sensitive as well.
It's something that we just couldn't be without and I use it very regularly. So I'm quite comfortable to use my full new opioids with our geriatric patients. It provides excellent analgesia, so therefore less stressful, much more smooth recovery.
And I know that I can rescue that bradycardia quite safely should I need to. Benzodiazepines, which is the posh fancy name for diazepams and midazolam. Diazepam is a licenced product for dogs in the UK, so that's what we'd use for, reach that for, but we would give that IV.
Midazolam can be given IM or IV and it's actually our choice for cats on a personal level. So minimal cardiovascular and respiratory effects can be noted. It's very, very minimal.
Therefore, it's deemed safe drugs to use. They have quite a short duration of action and we can titrate the dose accordingly, especially if it's a shorter procedure. Just be careful because if you give them a benzodiazepine and then wake them up 15 minutes later.
They can feel quite crazed. It is metabolised by the liver, so reduce the dose as we've recommended with other drugs if you know they have hepatic concerns. And you can reverse it with flail, Flamazenil.
I don't have to say that very often. I don't have to reverse it very often, but I would recommend you having the reversal in stock if you are holding these drugs. Also, I quite like, using these benzodiazepas, particularly for oral surgery or patients that haven't been eating very well.
Any surgery, cause it can actually have a side effect, making them feel a little bit hungry when they wake up, which can sometimes push them into eating that first kind of bite. And I think we all agree after surgery, once they've had that first couple of bites, it can really tempt them to get going and, and eating that bitch better. Alpha 2 agonists, I think people either love them or hate them.
They think it can be a drug for the brave, and I think you must be well educated prior to using these drugs. They will cause, dose dependent depression of the cardiovascular and respiratory systems, and it does require extensive hepatic metabolism. We don't tend to use them in our very geriatric patients.
Obviously, if they're incredibly aggressive, it might be something that we might add into our multi-modal approach. We will consider them if they're absolutely required, if we have to do a rescue sedation postoperatively, but we use a very, very, very low dose, much lower than any of the product sheets will tell you to, or any of your charts will recommend. Intravenously, we would use 1 to 2 mcg per kilo, so that's 0.00.
1, make per cake, very, very low. And we will give that to effect. Often we dilute that even further.
So we draw up the 1 to 2 mcg per kilo, and then we'll place it in the middle to the saline, give it a good wiggle around, and then we'll give it very slowly to effect. So we don't sometimes even use that much. Sometimes it's literally 0.5 a microgram per kilo.
If we have to go IM, we'll probably go up to 5 mcg per kilo, but we would be using that in conjunction with other drugs so that we have the motorous synergistic effects. Always, always all your patients, not just geriatric, please have the reversal agent drawn up to hand. You do not want to be trying to calculate and find that in an emergency situation.
And finally ACP, not a big fan for our geriatric patients because it does, it's very long lasting, we can't reverse it. It will cause hypothermia and hypotension, and it can be much harder to treat hypertension when you've already vasodilated the body, which is now getting cold. And so it just, it's really difficult to treat with your drugs and becomes much more laborious for you and stressful.
So I feel like there are other options for our geriatric patients. I'm not slating ACP as a drug. I'm not saying we shouldn't stock it or use it for appropriate cases.
I don't feel like our geriatric patients tend to fall into the cases that it would be appropriate to use it in my opinion and from the experiences that I have. So we're gonna finish up on a case example. Thank you very much for bearing with me, and I hope it has been helpful.
We're gonna talk about a, 11 to 15 year old domestic short hair, who has been owned for 10 years and was a stray prior to that, has mild hypertrophic cardiomyopathy, which has had an annual echo for the last 8 years with no changes. Blood work of biochemistry and haematology was clear. Otherwise healthy, had dental work 3 months prior, and we had read through all of the notes, to ensure that everything was fine and to look at what drug choices were used, how the recovery was.
I do this for all of my patients that have anaesthesia, but particularly the geriatric patients, see if they had any concerns under the GA and then you can see, oh, you know, they really struggled with their blood pressure. They used ACP. So perhaps I'm going to keep away from that.
Or they didn't use ACP, but there was an issue with hypertension, but they were bradycardic. I can see they use some glyco that worked nicely. So you're, you're better armed to go ahead with the anaesthesia.
But for this chap, he'd had dental work 3 months prior to being presented to the clinic, and no blood pressure concerns on the GA and no adverse events, events were recorded. The cat was coming in because it's tachyponic and slightly dyspenic, and a mediastinal mass was found on ultrasound. Due to being so dyspinic, IVC placement was not possible and pleural effusion had been noted on the ultrasound as well.
So this cap now needs a GA, for draining of the effusion, a biopsy of the mediastinal mass and the CT scan. So he is geriatric. So he is more likely to have concerns, but by having regular recent blood work, which was taken that morning, we know that we are not worried about the liver and kidneys.
We know he's got HCM, but the recent echo has established that everything's fine and nothing has changed. We are aware that he coped really well under anaesthesia 3 months ago. So we're gonna be looking at repeating some of those drugs, but they were given intravenously at the dental work and we've just established that this IBC is not going to be placed.
So we need to think holistically and the drugs, what do we need to do for this guy to get him stabilised, to get him with an IV to get him safely anaesthetized so that we can make him more stable by draining that. And then do our diagnostics and then be able to wake him up safely as well. So he's high risk for his pleural effusion and he's geriatric.
So he's classed as an ASA grade 3. And we will ASA grade all of our patients. Being geriatric doesn't pop you into a higher ASA grade as such, but as we've established, they're more likely to have something going on.
And that might be something that you didn't even know was happening, such as this guy. So for him, he was placed in an oxygenated incubator. We have incubators at the hospital which are great because they're see through.
You can really closely monitor your patients, and he was monitored for any further difficulty breathing, and an incubation tray was kept with him. The environment for him was kept nice and calm. He's older, he's stressed, it's an unexpected day out, and he's struggling with his breathing.
The last thing he wants is to feel stressed. We had to go for an intramuscular premedication because of the stress caused even when we tried a backlim IV. So we went for methadone, 0.15 meg the kick.
Now remember you can go any number between the numbers you wish for our drugs. We're very used to saying 0.1, 0.2, 0.3.
We can go 0.1, 2, make the kick, 0.15, the gig.
We don't want to give too much of this respiratory depression happens too strongly with this cat. He's already struggling, but he's likely to be painful. We do have to drain that effusion, and he is quite arthritic, so we do want to offer decent, pure new.
I look. We're going very multimodal here so we can use low doses of multiple drugs to try and reduce those side effects, and we're gonna try and use the drugs that have the least cardiovascular side effects and respiratory side effects because that's this, this is the main problem for this guy. So we've chosen midazolam 0.2 mg per kg, I am.
We've also chosen, and it will all go in the same syringe, alfaxolone 1 mg per gig, and that will go iron as well. Now, yes, for a 5 kg cat, this is a larger volume. You can split it over a couple of injection sites, but I think it's better to have a slightly painful iron injection in this instance with drugs that are going to keep them safer than to reach the metatomiline because we think it would work quicker and it's a smaller volume and it won't sting as much.
Yes, that's true, but had we given this guy an alpha 2, we would have been in quite a pickle with a respiratory depression and cardiovascular side effects that we would have seen with regards to the fact that he was struggling to breathe and he already has HCM. The sedation worked very, very nicely. It was given and then he was kept in the dark, quiet room, being monitored the whole time.
As soon as he got sleepy, he had a face mask placed with oxygen and an IV placed, and that IV tray was ready and close. The IV was placed and he was then induced using intravenous alfaxolone. The intubation tray had been with him the entire time, and once he was intubated, we were then able to perform IPPV should that be required.
We make sure that the appropriate breathing circuit was ready and checked and that we had emergency and supportive drugs calculated in place. The main thing you can see from here is how prepared we get for every single case. It doesn't matter what they're having, we will be prepared for them and we will look into their history and look at their disease processes and what they might need and have it.
And I'd much rather have 10,000 things to put away at the end of the day that I didn't need than be scrabbling around for the one thing I need and not getting it to my patient in good time. So there's lots and lots of different cases of geriatric patients. This is the one we had recently, and you can see that being prepared really is going to reduce your stress levels and give both you and the patients a better ride.
The full monitoring was ready with catography and temperature, oxygen saturation, ECG and blood pressure, warming aids, the CT machine is gonna be, it has to be quite cold, the room would be chilly, and obviously he couldn't wear a coat for his chest to be drained, but once it was drained, we placed that on. Soft mattress to lay on, both in the ultrasound room and in recovery. We're thinking about those hindlimbs for recovery, we're keeping that front end nice and sternal because anaesthesia doesn't end the minute you switch off that inhalant.
It continues into that recovery period, and it's not just about the drugs. We're gonna closely monitor them in the recovery, in the incubator for oxygen and warmth, and this guy will be regularly pain scored and his respirate obviously monitored. Temperature was also monitored and warming aids utilised, and he did very well.
So in conclusion, and thank you so much for staying with me, our animals are living longer, which is just amazing for owners, our, our pets are just the best things for us. I think we can all agree, those of us who got pets, we will happily have them live forever, but only if they're comfortable and happy. So as they're living longer, therefore we do need to expect to be performing anaesthesia on geriatric patients more often, and owners are gonna have those expectations that we can handle them safely.
But I do think with correct education, which is great that you're here listening to this webinar because you want to educate yourself and be more comfortable and offer a really good service. So with that education and preparation, we can manage them safely and offer them a continued quality of life, which is what's most important, and also to reduce your stress levels when anaesthetizing geriatric patients. These two books I find really, really helpful, and I keep them at work with me, or if I know I've got a big case coming up, I will read and I use them for this lecture too.
They are really insightful. They have different opinions from different people across the world about how we can manage our geriatric patients or patients with any other coexisting disease as well. So I do enjoy these books personally.
Thank you very much again for having me. I really enjoy teaching for the webinar vets and hopefully you can check out other webinars that I supplied to them and also they have so many and many other speakers of all subjects, so I'm sure there'll be lots of things on there to take your fancy. Please don't hesitate to get in touch, as I said at the beginning.
Although predominantly we are doing dental surgery, I do get involved with other surgery and we're anaesthetizing all types of patients with all sorts of disease processes. So if you have any concerns or any questions about particular cases or just wanted to chat. Or if I haven't been clear about something, feel free to email me or give me a call or WhatsApp.
We do talk about anaesthesia a lot, as well as dentistry on our Facebook and Instagram. And if you wanted to look at our anaesthesia support guides that are coming soon or our patient warming packs, you can do so on Etsy. And if you're interested in having, you know, webinars or face to face lectures at your practise, then just feel free to get in touch and it would be lovely to chat to you all.
I hope that you've enjoyed the webinar, and you've taken some notes to take back into practise. And thank you very much.
