Hi everybody, my name's Sophie McMurra. I'm a registered veterinary nurse and a veterinary technician specialist in small animal internal medicine. I work at North West Veterinary Specialists where I'm the head nurse of the internal medicine department, and today I'm going to talk to you about feline blood transfusions.

So blood transfusions can be a life saving therapy, and they can be used for a multitude of different conditions. The most common being anemias and sometimes coagulopathies, depending what you're faced with. However, there's certainly not a benign procedure, particularly cats more so than dogs.

So complications can occur. But it's our role as veterinary professionals to have an awareness of how to minimise those risks so that we can make these the transfusions as safe as possible. And we can do that by having a good knowledge of the careful donor selection, understanding the different blood types and why they're important, and also knowing what to do when it comes to monitoring the patients during the transfusion.

Now, cats, unlike dogs, have 3 different blood types. They have Type A, Type B, and AB. The most common in around 70% of cats is type A.

B is a little bit less common. However, it's more common in certain pedigree cats. And then finally we have AB, which is only in a tiny percentage of cats, and it is rare in all breeds.

Now there has been a more recent discovery of another blood group in cats, and this is called Mic. So cats can be Mic negative or MIC positive. And if you give a transfusion to these patients, they can have a reaction.

They can occur, however, because it is still quite new, we're unaware of the frequency of a reaction or the severity. Because we just haven't seen many cases of it, so we don't have much data. And the some of the complications that we have seen have been quite severe.

So this is again, another reason why cross matching is so important in cats and we'll delve into that a bit deeper in a moment. Now with any species, it's really important to find out the blood type before we go and give a blood transfusion, but specifically in cats, they are at greater risk of a transfusion. And the reason for this is because they have naturally occurring aloe antibodies to the other red blood cell types.

So for example, if you have a type B cat and you give a transfusion of type A blood, they will already have antibodies that will attack those red blood cells of the type A blood. So it's really important that we find out the blood type of the cat and we give them the correct type to match their blood. Because even a few mills can have a fatal reaction in cats, and we don't want to cause more harm than good when we're given a transfusion.

So for this reason, they should always, always be blood type and cross-matched prior to every transfusion. So when we look at the 3 different blood groups in cats, type B is the most antigenic. So this means it has a high number of naturally occurring anti antibodies to type A blood.

Whereas type A is less common, less commonly found to have naturally occurring antibodies against type B. So type B is the most antigenic, the most, the one that carries the higher risk. And then we have also type AB, and this is less likely again to have naturally occurred in antibodies.

And when we look at giving a transfusion to a type AB cat, it should be type AB that we give it, which AB doesn't mean that it can receive Type A or B. It's another specific group, so it needs A B blood. And if you're absolutely stok for options, you don't have many options to choose from.

You can give type A to any cat if it's an absolute emergency. Obviously it does carry a risk of having some antibodies against that blood type if it's not the correct type. But it's the the least antigenic type and it's the more commonly available.

We said that 70, around 70% of cats are type A, so you have the best chance of trying to gain a type A sample and it's not very common that it has a naturally occurring aloe antibodies. So you've probably got the best chance of success with a type A blood. But if you can, you should always blood type first in the ideal situation.

Now if you haven't seen the blood typing kits before, this is an example of one of them that we use in-house called the Quest. They're available in dog for dogs and cats. And this is just a really quick, easy blood typing in-house kit.

It's done within about less than 5 minutes and they're really easy to use and it just tells you it gives you this this little. Little device here which will tell you whether it's A or B or AB. And then you also get a little card or like a certificate that you can give to the owner so that they can always be aware and they can keep it for their records.

Once you've blood typed your patient, put it on the clinical records and it's there for life in case you ever need it in the future. So when we look at cross matching, this is a really, really important tool that we can use and I would say to use it in every single cat for every single unit of blood. And it helps prevent any, the risk of transfusion reactions.

And it just tests, tests the donor blood with the recipient blood, and it will tell us what is likely to happen in that patient's body if we were to give this donation to this recipient. And it will allow us to identify any of those naturally occurring antibodies that we've talked about in cats. And remember, if you do give one unit of blood and then you have to open another unit or you have to get it from a different cat in the future, you do need to cross match each unit.

Because they're coming from different donors. And if you don't cross match the patients, we're just increasing the risk to our patients for giving a transfusion. And it's a greater risk.

We're going into the unknown, so we don't know what the patient is going to do and how they're going to react to this donation. So it's really important to, we'll talk about the criteria in a moment, but it's really important to get an owner, thorough owner history to know whether they've had a transfusion in the past, because if they have, they can build up antibodies. This is an example of the cross matching kit that we use.

So you can see in the, in the middle, that's the donor blood. And you've got two clear tubes either side. So on the left, you've got an example of a positive reaction.

So if you were to use the recipient blood with this donor blood, it is likely to have a reaction if your cross matching looks like that. Whereas you can see the tube on the right, the blob of blood is down at the bottom, and that's an example of what a negative cross match looks like. And you can see that our donor blood is negative because it matches that tube.

So that tells us it's negative for a reaction, so we should be safe to go ahead. Now there can be some limitations with cross matching kits and particularly for patients with IMHA if they have a really strong agglutination, sometimes that can make it almost impossible to cross match these patients because it just doesn't, it just doesn't work properly. It doesn't give you an accurate result and it just gives you a positive cross match for every, every blood that you that you try.

And in this instance, if you do have an IMHA patient, I would still say to do this because it's only in the really severely agglutinating samples. But if you are coming across this issue, you can send the blood externally to the lab, and they will do things like washing the cells, and they can, they can perform an external cross match. Now, sadly we don't tend to have feline blood banks available, readily available in the UK.

We don't have a a feline blood bank. We have a canine blood bank. And this is because the red blood cells of cats have a limited storage time.

So, especially in the emergency situation, it can be really difficult to find a suitable donor in a short space of time. And some some practises do have a list of donor cats, and you can pop up a little advertisement in your waiting room. Some owners will be happy to add the cats to the list.

You'll bring them in, you'll screen them and then if they're compatible, you'll add them to the list. And other practises, this is less common, but other practises do keep some in-house cats, and they are used for blood transfusions. So there are a couple of options.

So when we find some patients that are willing to become donors, or the the owners have signed them up. There are some specific sets of criteria that they need to match. So we want them to have a calm temperament.

We don't want a nervous, scared, worried patient coming in. Remember that cats can't consent to this. This is us consenting on their behalf, so we want to choose the most calm patients if we can.

We don't want to cause any unnecessary stress to these patients. We need to do a full health check, so they need to be healthy, fully vaccinated, worms and fleas. They should have a lean body weight of 4.5, and I say lean because they shouldn't be 4.5 and be overweight.

They should be between the age of 1 and 8 years old, and ideally they need to be an indoor cat because if they are going outdoors, they are a higher risk of being exposed to infectious diseases. We wanted them to have a no travel history outside of the UK or on any medication. They can't have had a transfusion in the past and they can't be currently pregnant.

We used to say that they can't have any previous pregnancies. We now say that that's OK as long as they're not currently pregnant. OK, so if they've passed all of those, we need to get them in and we need to do a full TPR.

We want to run bloods, check biochemistry, haematology, check there's no underlying conditions like liver disease or chronic kidney disease. Check your PCV and your total protein, we want the PCV to be a minimum of about 30%. And we need to do an infectious disease panel, so FIV FELV and mycoplasma hemophilus.

Mycoplasma hemophilus is a PCR, so that would need sending off. But if you are putting the patient on a donor list, then we should have time to do that. They should be negative for any vector-borne diseases, so if they're from a particularly endemic area of a certain infectious disease, we should be screening for that as well as an additional test.

And on the list is an echocardiogram, so you might see this and think, oh, that's a little bit. That's a little bit too much. However, the reason for that is because 30% of cats with cardiac disease have no murmur.

So you can have 30% of cats who have cardiac disease, if they are undetected, you can withdraw 10% of their blood volume, and that change in blood volume can tip them into showing signs of cardiac disease which can help unmask heart disease. And by performing an echocardiogram beforehand just helps. Be aware that we are clear that they were sure that there's no cardiac disease and we can Reassure the owner as well that we're not likely to unmask anything.

However, if you don't have this available, there are some clinicians that will say, I've listened to the patients, it's a regular heart rhythm with no arrhythmias. There's no gallop rhythm and there's no murmur. So for that reason, I'm going to go ahead and go ahead and use this as a patient to donate blood.

And that's absolutely fine, as long as we just, we're honest with the owner to say, you know, we can't absolutely rule out cardiac disease which does carry a greater risk. And then if all goes well, we can go on blood type and cross match the patient to see if they are compatible with our recipient. So when we've got the suitable donor, we should be sedating the patient for the blood collection.

And the reason for this is, even if you've got the most chilled, relaxed cat, they now need to have a needle in their neck for 20 minutes. And even the most relaxed cats, that's not a very nice experience, and we want to prevent any negative experiences as much as possible. So a sedation allows them to be nice and relaxed, they're still, so less likely to have any risks from movement.

And if you do have any brachycephalic cats like your Persians, you may need to anaesthetize them so that you can secure the airway. So this just minimises any risk of complications. If you think of a jugular vessel in a cat, it's quite small.

And especially when you look at the size of the large bore needle that you need, you don't have much room for movement without causing trauma to the vessel. It minimises stress for them, for the owner, and also for us as the veterinary team. And it will also improve your own satisfaction.

So if they've brought in a nice calm cat and you send them home and they're tachycardic, tachypneic, open mouth breathing, looking really stressed, we know how sensitive cats are to stress, so we We need to do our role as a veterinary team to reduce that as much as possible, because if they've had a nice sleep, they've woken up, they've had a meal, they've gone home, they're oblivious to anything happening. That is a much nicer experience for the cat and also for the owner. And for us So I won't talk too much about the sedation, but it needs to be a quick onset, whichever drug you choose, such as like an alpha 2, a quick onset, it needs to provide an adequate level of sedation, and ideally it needs to be short-acting or something that you can antagonise.

You can also use local anaesthetic creams such as ELA cream and pheromones that you can spray just to make the environment a little bit more feline friendly. And treat this sedation the same as you would with any other sedation or anaesthetic. They need oxygen via a mask.

You need to link up if you have a multiparameter machine, link it up, use your ECG, your blood pressure so you can see any rapid changes if they occur. Pulse oximeter can go on the, it tends to work quite well on the toes of cats. And you need to be performing your temperature, pulse, respiratory, mucous membrane, and pulse quality check every 5 minutes as you would for any other patient.

And we know that cats like to get cold straight away as soon as we give them any drugs, to prevent hypothermia. I tend to use a bear hugger with cats because I think they lose temperature really quickly, even with a a heat pad. So a bear hugger if you have one, and we tend to use children's socks on the limbs of cats because they're the perfect fit and it's just that extra level of of warmth to keep their extremities warm with a blanket over the top.

OK, so before we go ahead and take the blood from the patient, we need to prepare. So gloves may seem a very obvious one, but the amount of people who wouldn't think of using an aseptic technique for something like this, you would be surprised. So gloves, if you have surgical gloves, that's even better.

We're dealing with a cat, so quiet clippers if you have them, and we need to do a nice big surgical clip. So the last thing you want is your beautiful aseptic area. Everything's prepared really nicely, and then you've got this tiny little clip on the cat's neck as if you were just taking a blood sample, because then you're at greater risk of passing the needle and or the syringe and your glove through fur.

So do a nice big clip so that at least the needle and syringe doesn't have to sit or go near any fur and you can just keep your hand away from the cat. And you're using a butterfly needle, so you can do that. We need to prepare the skin with a surgical skin solution and surgical spirit, and then you choose the appropriately sized syringe.

So if you're going to get 50 or 60 mLs, you might want to use a 50 or 60 mil syringe, but I personally feel that my hand gets really tired with those strong plunges, so I prefer to use multiple 20 mil syringes if I'm going for an open collection technique. The butterfly catheter should be 19 to 21 gauge with a three-way tap. And you can use a blood collection bag.

You can take the CPDA out of the collection bag and put it into your syringe and just mix it along the actual body of the syringe to coat it with an anticoagulant, or you can just withdraw the CPDA volume from the bag and then drain, leave the remaining amount inside the bag and drain the blood directly into the bag itself. And this is called a closed collection method, and I'll talk about the pros and cons of both of those methods in a moment. And then for afterwards, once you've finished your collection, you want a dressing material for the neck just to add a little bit of pressure for 5 or 10 minutes.

You should have an IV cannula in every sedated patient in case of an emergency. And donations over 10 mL per kg, some clinicians say they don't give fluid therapy to resuscitate because it's a small volume, but others like to use IV crystalloids 2 to 3 times the volume withdrawn, and they will give that back over 1 to 2 hours. And also remember we do need to provide oxygen and we do need to lubricate the eyes.

So we need to calculate how much blood we're going to withdraw from our patient. So we tend to say the patients can donate 20% of their blood volume every 4 weeks. Now we estimate a cat's total blood volume to be anything between 50 and 60 mL per kilo as a rough figure.

With the maximum volume that we want to take, being 10 to 12 mL per kilo. Now to put that into context, if we have a 5 kg cat, for example, We can take up to 20% of their blood volume, but to keep the maths easy, let's say we'll take a 10% donation. So 5 kg, we need to work out the total blood volume 5 times 60 mLs.

Gives you 300 mLs. So 300 mLs is the cat's total circulating blood blood volume as a rough figure. 10% of 300 is 30 mLs.

Divide that by the patient's body weight and you will get 6 mL per kilo. And we've just mentioned that the maximum volume should work out of anything between 10 to 12 mL per kilo. So 6 mils per kilo is way below that range, and we know we're absolutely fine to go ahead with that.

You want to be given a citrate-based anticoagulant, 1 mL per 7 mLs of whole blood. And this is some can be something like CPDA which is found in the collection blood bags. You can just use that, which is absolutely fine.

And if you are using 20 mL syringes, that works out as 2.85 mL per 20 mil syringe. So I would draw that up and pull the plunger back, coat, mix that syringe so that you coat in the wall of the syringe with an anticoagulant, and then just push the plunger back in to get rid of any air.

We don't want any air in that system at all. And if you are using the blood collection bags, so the closed method, you can, it should say on the bag how much anticoagulant is in there. So just remove any excess volume, leave the remaining dose in there and withdraw the blood directly into the bag itself.

And when we look at whole blood, we tend to say 2 mL per kilo. Of whole blood will increase the recipient's PCV by 1%. Whereas if you are lucky enough to get hold of Pachter blood cells, we say we halve that because the blood cells are much more concentrated.

So it's 1 mL per kilo, we'll increase the patient's PCD by 1%. And the ideal PCV that we want to achieve is around 20%. Now these are rough figures.

If you don't achieve 20% exactly. Don't worry, we're just trying to get this patient into a more stable zone away from such a low PCV so that the body can cope. We can get our red blood cells up, we can meet our oxygen demands so that we know there are red blood cells, deliver oxygen to our tissues, and we're just getting them into a safety zone.

So you don't need to achieve a normal PCV because that will be quite a large volume to administer. And if you just look at this image that I have here, this is a cat PCV of 6%. And I tend to find that with cats when they present, they can go down to something like the lowest I've seen is 5 or 6%, and they will be sat quietly.

Sometimes they may be collapsed depending on the rate of the, the anaemia that's the onset. If it's acute, they're more likely to be dyspneic or you know, not coping quite so well because they haven't had the time to compensate. Whereas chronic anaemia as they can cope really well with and they'll be quiet, they'll be tachyneic, tachycardic, but they don't kick up much of a fuss.

Whereas a dog, they will be dyspneic, completely collapsed at around 10, 11%. Maybe that's just because a dog's PCV sits much higher than a cat. A dog's is anything from 35 to 55, whereas a cat is naturally much lower, to around 27 to 45, depending on the textbooks that you read.

So they need to lose less to get to that smaller volume, but it's absolutely You know, common to see a cat's PCV in the range of 5 to 6%. I've seen that many, many times. But I don't think you'd ever see a dog with a PCV of 5 to 6 because they tend to be, they tend to cope.

Less well than cats do. So when it comes to collecting the blood, you can either lay them in lateral recumbency or you can get an assistant to hold them as if you would for a blood sample, depending on what your preference is. I personally think they're sedated.

Let them relax and you can relax, lay them in lateral recumbency, and we always use the jugular vessel. You want to insert your butterfly catheter with the bevel up as you would with any other needle, and ideally you want to be doing this clean stick, so one go straight into that vessel. We don't want to be stabbing around in the dark.

If you can't see the vessel or feel the vessel before clipping and preparing this patient to check the other side, have a good feel to see which side is better. And I tend to find when you're raising the vein rather than using your thumb upwards, which is just a small area that you're raising, use it laterally, and that will just allow you to put pressure on a larger volume, larger area, and you may well see your vessel a little bit easier if it's slightly off to one side. But have a look, have a feel.

Before you go stabbing, because then your greater chance of getting a nice clean stick one go into that vessel and you're not traumatising around the area. You need an assistant to hold the syringe and aspirate the blood nice and gently. Any excessive pressure on that syringe can collapse the vein around the needle and prevent the blood from flowing.

So if you do notice that the blood has stopped or slowed down, just ask the assistant to slow down that pressure. And this is another reason why I prefer to use 20 mL syringes rather than the 50 or 60 mLs because they have quite a large volume and there's a lot of pressure on such a small vessel. And as the assistant is aspirating the blood, ask them to rotate the syringe to mix the anticoagulant with the blood as it comes back into the syringe.

And I mentioned before, the open and the closed collection system. So the open system can be used within 4 hours, ideally of collection, or if you keep it in the fridge, it can be used for 24 hours. Another bonus of using multiple 20 ml syringes because you can have one open, giving it to your patients while the other two are in the fridge, and they're perfectly fine, they're not at room temperature and then they're not at a higher risk of contamination.

It's really important that we don't allow any air into the system, no matter what system we're using because that can encourage bacterial growth. And the closed system, which is where you drain it straight into the collection bag, they say can be OK up to 35 days. However, some studies have shown bacterial growth in the closed systems on day 35.

So both the open and the closed technique carry a risk, and we think that it's more down to the aseptic technique, the handling of the blood and the patient, and also the experience of the veterinary staff. So I personally prefer the closed method. I think it's neater, it's easier, and it allows you to use smaller amounts while there's more in the fridge that can be used at a later date.

And you can also do this just by withdrawing some into a syringe from the bag, but I just prefer to use the open technique where you will find your preference. So before we go ahead and administer the blood, once it's collected, we need to do a few more things before we go ahead. If you have a multi-parameter monitor, put one on the donor, and this will allow you to just check the donor is OK and it will allow you to regularly perform your monitoring that you need to do during the first half hour of the transfusion.

We'll talk a bit more about that in a moment. We also need to warm the blood to room temperature, if you've got it out of the fridge. And to do this, you should ideally put it in a warm water bath, which is about 20 degrees, degrees C.

I have seen people put them in the microwave, which is an absolute no go. It will destroy the red blood cells. I've seen them put them on the radiator as well.

Again, too hot, don't do it. Just put it in a nice warm bath. If you can't do that, just warm it in between your hands.

And actually, the pet blood Bank have done studies to show that by the time it gets from that syringe or bag down the given set and into the patient, it will be room temperature anyway. So it's up to you. It depends on how quickly you need to get this blood product in.

As a nurse, everything about that is telling me to warm the blood up. It just feels so wrong to give a refrigerator product to a cat, especially. But the Bank have said that it should be OK, so it's good to be aware of that, for if it is an urgent situation.

You will also need need a hemic blood philtre, which you can see on this image here, and you can see this is being put on the ends of the syringe and then the given set or the extension set is at the end of that. I personally would prefer to put that as close to the patient as you possibly can. So if you have connected your extension to a T connector on the IV cannula of the cat, I would put it there.

So it just prevents any coagulation or anything happening after that philtre, and it means that just before it's getting to the patient, it's filtering everything out. So I prefer to have it as close to the patient as possible. And your method of administration, if you have a syringe driver, that's perfect.

You can get really tiny volumes, especially for your introductory dose. And if you've drawn it up into syringes, then a syringe driver is perfect for them. If you are using an infusion pump, you do need to do this with caution because there have been studies that have looked at the red blood cells after using an infusion pump versus without and there have been some destruction to those red blood cells.

If you have no other option and you are using an infusion pump, what I would say is clear off all information on that set, on the given set on the infusion pump, put in your rate of administration, your volume to be infused, and your volume infused. Now that volume infused is the important one because I've had it before where I've set the infusion rate. And then after an hour it should have administered just as an example, 10 mLs, and I look and think, hm, it doesn't look like 10 mLs has gone out of that syringe or out of the bag rather.

And then if you check the volume infused, it's a much smaller dose than what it's set to. And that's because they're not calibrated for blood. Blood is much more viscous than fluid therapy.

So they're just not calibrated and more errors can occur. So if you look at that volume infused, keep a close eye on whether that's correct according to the rate and check that it's going in at the correct rate. And blood should be kept at room temperature for less than 4 hours, ideally to prevent bacterial growth.

However, in certain patients, you may want to give it over 6 hours if heart failure patients or heart patients with cardiac disease as an example or elderly patients. But again, that's the beauty of having it in multiple syringes. And we shouldn't be using any calcium containing fluid therapy alongside blood products.

If we're giving whole bloods, then you may not need any fluid therapy anyway, especially in cats who are at higher risk of volume overload. Whole blood contains the plasma. It's the full product, so you may not need to give fluids alongside because you are just increasing the risk of a volume overload for the patient.

And the reason why you can't give calcium containing fluids such as Hartmann's condition is because the citrate is an anticoagulant. As part of the coagulation cascade, that collates calcium so that it can't clot the blood. But if you're given a calcium containing fluids, it can overwhelm the citrate and stop it from being able to act as an anticoagulant as effectively.

So you can get small micro clots occurring in the the given set. So administration should be between 4 to 6 hours, 6 hours if you need to reduce the risk of circulatory overload or heart failure to the patient. It can be given if your patient is collapsed, tachycardic, tachypneic, hypotensive, you may want to give it a bit quicker, so that can go in over 1 to 2 hours if needed.

And the signs that we need to look out for while we're administering this blood product are things like vocalisation, tachycardia, tachypnea, restlessness, hyper salivation. We know how much cats love to hyper salivate, vomiting, diarrhoea, they can get facial swelling or urticaria. I've seen this happen in a dog once where they had a transfusion and within the 1st 5 minutes you could see its face swelling up instantly, particularly around its eyes, and it got hives all over its body.

And then it was just rubbing its face on the floor of the kennel, it's bed in the the cage door because it was just so itchy. You can see a change in blood pressure, again, another reason why a multiparameter multiparameter monitoring machine is perfect. But if you don't have that, you can notice the changes in the pulses.

They may become weak. You can also see pyelo erection, which is where the blood stand, sorry, the, the hairs stand on end. And you can see respiratory distress.

And if you do see any of these signs occur, it could be the sign of a transfusion reaction, so you need to stop the transfusion straight away and Assess the patient and seek help. OK, so now we've got the blood, we've got everything ready. We need to monitor the patient while we're administering.

And you may think, oh, I've done a million blood transfusions in dogs. How can this be much different? But they really are.

They are a higher risk and we do need to treat them. Obviously you need to be careful with any blood products or any transfusion, no matter what the species. Cats are just that little bit carry a greater risk.

So if a reaction is going to occur, it's likely to happen within the first half an hour. However, it can happen at any point. So, before we go and take any monitoring or start any monitoring or start the administration, we need to do a baseline TPR.

Temperature, pulse, respiratory rate, blood pressure, ideally, especially if you've got that multiparameter on, then that's great. Look at our oxygen saturation if you can, and look at our mentation as well and make a note of all of those things. We have a sheet in our hospital and we have all of these things on there so that we can regularly check and just make a quick note if we see any of those abnormalities on there.

And it's really important to say that the baseline TPR should be done immediately prior to the transfusion. It's not good enough to say, well, I did a TPR at 8 a.m.

This morning. The cat's been in the hospital for 6 hours and it's now 2 p.m.

We want to get the most accurate figures that we can so that we know if there are any alterations or any changes, we know that it's happened since we've started that blood, and it's not just because the cat's been in the hospital and become stressed for the last 6 hours. So get that baseline TPR straight away before you start any observations. And of course we need to constantly observe these patients for the for quite some time when we're given the transfusion.

And for the 1st 15 minutes we need to do a TPR every 5 minutes and look out for those signs of reaction, and this is the time when we just give a tester dose. So we're given 0.5 mL or 0.5 mL per kg per hour.

It's a really tiny dose. And the reason for this is it, it just allows us to trickle in a really small volume so that we can intervene quickly if anything happens and reduce the risk of anything becoming fatal. If after 15 minutes, you're absolutely fine, and you're happy with everything, there's no signs of reaction and TPR is all OK.

You can double that dose. So increase it to 1 mL per kg per hour for another 15 minutes. You're not out of the woods yet.

The first half an hour is the most dangerous, so we need to continue the monitoring just with a slightly higher rate. If no signs of happens within that 1st 15 minutes as well, you've passed your half an hour, you can go and give the remainder of the dose over 4 hours from the start time. We still need to monitor our TPRs every 15 minutes until at least we're past the first hour of the transfusion, and then you can go hourly as long as you're comfortable with that.

And if you do need to give this more rapidly, then you can give it over 1 to 2 hours. Ideally, if you can still start with that tested dose of 0.5 mL per kilo, because we still want to know if any dangerous reactions are going into a care, we want to be able to stop that before we've administered mills and mLs to this cat.

Because that's when we may start to see fatalities. If you can't, and the cat is really collapsed and we need to get it in quickly, then fine, we can't do it. But let's take every precaution that we can if we can.

And then once the transfusion has finished, we want to repeat the PCV at the end to see what difference our blood transfusion has made. And if the patient does have a reaction, Then there could be two different types and a multitude of reasons as to why this has happened. And we categorise them into immunological and non-immunological.

So an immunological reaction is caused by the patient's antibodies. They've reacted to the recipient's red blood cells and they have destroyed the red blood cells. It will, it may well have an acute onset and it will result in hemolysis of that transfusion.

So it will attack the red blood cells of your nice fresh donation of the blood and it will get rid of them, which is really sad. And then we have non-immunological, so this could be caused by us. So this is caused by incorrect handling or storage of the product prior to it being transfused.

So maybe we have warmed the blood up in a microwave, and we've caused hemolysis of all of those red blood cells, we've destroyed them all and then we've gone and given them to the patient. Of course that's gonna cause a reaction. This could also be due to the administration of stored products to a patient, especially if they have things like liver failure.

And there have been studies to show that with certain conditions such as IMHA for example, if you give a fresh blood sample or blood product to a patient that's within 7 days of of taking it, then it has a better prognosis. And the longer it goes over 7 days, the poorer the prognosis is. And this is because those red blood cells are alive.

They're still producing ammonia and waste products, and then if you go and give it to a patient, say with liver failure or in cases like IMHA they're not in liver failure or they don't have liver disease, but the liver becomes overwhelmed because of. The IMHA. So it may not have the capability of getting rid of that ammonia and converting it to your ear so that it can be excreted by the kidneys.

So you can then start to see other issues. So the fresher the sample, the better. And then we can also see one of our reactions that we can see is volume overload.

Maybe the patient has cardiac disease and we've given it a little bit too fast, or maybe it doesn't have cardiac disease at all, but we've given fluid therapy alongside it. So with a whole blood transfusion. It's everything, it's the plasma as well.

So you don't always need, unless you have a really dehydrated hypovolemic volume depleted patient. You shouldn't really need to give any fluid therapy alongside a whole blood transfusion. Now I will just mention that you can occasionally get acha blood cells.

These are more recently available and they can be imported from Portugal or from different parts of Europe. It's become a little bit more tricky to get these since I assume it's because of Brexit, and now you need to order them specifically for the one patient, so it's, it's ordered on prescription for one patient rather than being able to just order in a load of them to keep in storage like you would for a dog blood products. And if you do give red blood cells, you can then give fluid therapy alongside more safely.

And that's because it just contains sorry, it just contains red blood cells. It doesn't contain any of the volume to go with it, so any of the plasma or serum. So you are much safer to give fluid therapy alongside without having a greater risk of volume overload.

Once you've given the transfusion, you can go on the International Catcare website and it's absolutely full of really useful information. Now this leaflet is available and this is on blood transfusions in cats, and this is for the owner. But the website is full of things for veterinary professionals and for the owner as well, and this particular leaflet is really useful because it will just help the owners understand what we've done, what the process is, what the risks are, and why we've given a transfusion.

And it's also really useful to, I think owner education is a vital part of our role as RVNs or that. Because we need them to understand, and they can be really, really helpful if we do get them involved and they feel involved in the care of their their pet. After all, it's not just us who do all of this important, these important things.

It's the owner wants that pet is back at home. So the more we can get them on board and to understand why things are so important, like what we've had to do for a blood transfusion, the better. And it will just help them understand small things like why it's important that if the cat ever needs a transfusion again in the future.

We need to know that it's had one in the past, if it goes to a different, maybe an out of hours vets, they need to know that information because they may not think to mention that because it's irrelevant. So the more we can educate the owners, the better, and this leaflet is really useful, but there's absolutely tonnes of information on there for. Cat owners and for veterinary professionals as well, so I would encourage anyone to go and have a read and it's all the most up to date and it's where the, the consent, a lot of the consensus statements come from as well.

OK, so that's all from me. I hope you've enjoyed it. Thank you very much.

And if you do like things internal medicine, you can go on my Facebook or Instagram page and it's called Veterinary Nurse Medicine Geek. So follow me for any veterinary nurse medicine updates. Thank you.