[00:00:02] Introduction: Welcome to All Cats Considered, a podcast from the Feline Veterinary Medical Association.
Here we interview professionals from across the veterinary world and take deep dives into the latest evidence based research, developments, studies and guidelines that improve feline health and well being.
We are the home for veterinary professionals seeking to enhance the care of cats through high standards of practice, continuing education and evidence based medicine. In each episode you'll hear interviews with a variety of experts in our field covering a wide range of topics and the latest developments in feline health. We'll share the key points you need to know to improve your patients care.
Let's dive in and listen to this week's experts.
[00:00:45] Gómez-Mejías: I'm Yaiza Gómez-Mejías, iCare Veterinary Community Coordinator. And today we're diving into something that often gets that heart racing medical emergencies. We are incredibly lucky to be joined by Nicki Reed, a feline specialist and the author of a fantastic JFMS Spotlight review series on this subject.
Very welcome Nicki.
[00:01:10] Reed: Thank you Yasia. And thank you for inviting me to do this podcast.
[00:01:13] Gómez-Mejías: So your first article tackles everything from that initial "oh no" moment to the full workup of very complex cases.
So we got a few questions about this article. Emergencies can turn up at any point during the day and how can receptionists, nurses and assistants contribute to an efficient triage while we speak to the owners?
[00:01:40] Reed: As you say, they can turn up at any point and sometimes we get forewarnings, sometimes the owners will phone in, which means that the team can get a little bit of preparation.
Sometimes they just turn up on the, on the doorstep. I think the role of the reception staff, obviously they're the first kind of friendly face they can reassure people as they, as they walk through the door and put a call out to get the medical team there to a nurse and a veterinary surgeon available to assess the patient and then just chat to them, get some details as much as possible whilst the nurse and vet are triaging the emergency patient.
[00:02:17] Gómez-Mejías: It's so important, isn't it? I noticed that a lot in practice. One day when you go to a clinic, like we were talking before about being where you work, when you change clinic and you find a place where the receptionists are particularly good and you have the information you need to start with the consult, that makes a huge difference.
Most of us don't have a dedicated feline intensive care unit.
Are there any simple ways to optimize a shared dog and cat treatment area to reduce stress for fragile emergency patients?
[00:02:53] Reed: Yeah, I think this is a real challenge because even in referral hospitals, very few have a dedicated area specifically for cats.
Obviously there are guidelines under Icatcare, how handling of feline patients, how to make your environment as cat friendly as possible.
But that doesn't. It can be hard to apply those to a busy area such as an ICU type area or an emergency, such a triage facility.
I always try and get some Feliway on the blankets if we're going to be putting the cats onto that. Try to put visual barriers up so a kind of sliding curtain or screen can be useful if that's feasible. If possible, if we have got any noisy dogs in our ICU that can be moved elsewhere, you know that they're often noisy because they're getting better. We move them out as much as possible.
We try and keep cats to separate side away from the dogs as much as possible, but they will still unfortunately be able to hear the barking dogs or noisy dogs. They will still be able to potentially smell them as well.
And just trying to make sure that everybody uses calm and quiet voices as well. So it isn't ideal but we just try and make the best of it where we can.
[00:04:16] Gómez-Mejías: Thank you. Yep, that helps a lot, I think. And there are multiple resources from international cat care where tips are shared to make the practice more cat friendly, regardless of whether it's for different species. You mentioned that sometimes for cats with respiratory distress we need to do the physical exam in stages. I think you call it like the piecemeal or something like that. Piecemeal exam. What are the most important elements of the clinical exam in those first few seconds?
[00:04:51] Reed: I don't think you can underrate a visual observation.
So you know, these cats can either be getting oxygen by flow by in a table or if you have got an oxygen kennel, they can be put in there and you can just visually watch them for a minute or two, observe their pattern of breathing, get an indication of just how distressed they are whilst they're getting that, that oxygen supplementation.
Then I would focus on auscultation as my next stage. Try to do that as quickly as, as possible and then give them a break while they again are getting some more oxygen before maybe moving on to something like so a thoracic or TFASTs, thoracic ultrasound, assess for things like fluid.
I'm a little bit hesitant to be doing things like open, opening the mouth and checking color. Maybe immediately you can get sometimes get an idea of the color from the planum nasale if it looks pink or if it's looking pale. But I don't like fighting with them, opening mouths. I will delay things like abdominal palpation the first instance until I feel that that breathing pattern is a little bit better controlled.
[00:06:01] Gómez-Mejías: Yeah, I feel that sometimes when you feel that we have to do a lot because the more urgent the case, the more we have to do, and there's a tension in the room and every member of the team is kind of rushing and trying to do something when sometimes you feel kind of weird if you are not doing anything at all. But just observing and actually observing is a lot, is a lot.
[00:06:27] Reed: That lets you know, is it upper respiratory tract, is it lower respiratory tract? And that degree of abdominal effort that lets you know, you know, are we getting paradoxical breathing, you know, where the chest is almost moving in and the abdomen is moving out because of that increased effort? That's an indication of a severely distressed cat. So that doesn't even rely on a stethoscope. That's just your eyes that are telling you that.
[00:06:51] Gómez-Mejías: The vet's eyes. Yeah, we have to value our eyes, I think. It's not the same if any random person looks at the animal, but if we are looking at the animal, we are obtaining some more useful information, probably.
The 2024 RECOVER guidelines introduced some changes in the approach to cardiopulmonary resuscitation. What compression techniques should we now be training our teams to use on cats?
[00:07:17] Reed: Yeah, so previously the guidance was effectively one position with your four fingers of your palm underneath the cat and your thumb used for compression.
And that can actually be quite a fatiguing technique to use. I would struggle to maintain that for a minute, which is the recommended time, before swapping out.
You now have an option if you can use a kind of single palm to compress the chest whilst using your other hand to kind of steady the back to stop the cat moving away from you, which can be another issue.
Or you can use both palms of the hand or forefingers of the hand underneath the cat and both thumbs on top of the cat to compress down. And that, again, is a little bit less fatiguing. Still, not to use that kind of double palm compression that's often used in dogs, because that will compress the thorax too deeply and you're risking causing trauma, fracturing ribs, etc. in cats, because their chest just can't take that pressure that you can apply if you're using both palms on top of each other like you would for a dog.
[00:08:21] Gómez-Mejías: Cats are famous for hiding things. What are the main differences between cats and dogs in shock?
[00:08:27] Reed: Yeah. So one of the big things that we don't see is we don't see that kind of compensatory or hyperdynamic phase of shock that we get in dogs, where we often have tachycardia, tachypnea, maintaining a normal temperature, for example. Often when we see cats presenting in shock, they've progressed to the stage where they can actually be bradycardic, very often hypothermic, altered mentation, reduced blood pressure. And I think bradycardia is very often underrated in cats. I often see reports where cats have got heart rates reported in their clinical notes of 140, 160, and nobody thinks that's abnormal. I get very twitchy at a heart rate of 140 or even 160 in a cat because most cats that are alert and aware in a veterinary clinic environment are going to have a heart rate of at least 180. So, yeah, bradycardia is something that we need to put on the alert. And hypothermia can be associated with a poor prognosis as well. So we should be taking these temperatures and warming them where we can and improving their circulation to get that perfusion better so their temperature comes up.
[00:09:42] Gómez-Mejías: But talking about temperatures, this reminded me of a question I got from somebody the other day about where do you measure the temperature? Because we have a paper called axillary temperature. Where do you measure the temperature in these cat?
[00:09:58] Reed: I think when they're in shock, you know, I think your rectal temperature is probably going to give you the most accurate reading. The axillary temperature, we tend to reserve more for cats that get distressed by that.
You could certainly consider it in cats that are in respiratory distress, for example. But if you've got a cat who's in shock, and particularly if their mentation is altered, then I think the rectal temperature would give you a more accurate reading.
[00:10:24] Gómez-Mejías: Very good, thank you. Yeah, I think we all feel more confident with the rectal temperature because we've been doing it for our entire life as well.
[00:10:33] Reed: I don't think we're familiar enough with our conversion rate of, you know, the axillary temperature is always 1.5 degree less than a rectal to be using it reliably in that respect.
Yeah. And just going back to the other thing that you said about the difference between cats and dogs in terms of shock, I think the other thing that we need to be mindful of is the fluid volume that's given for resuscitation.
I think over the last 10 years or so, we have moved steadily away from shock doses into more boluses to potentially reach up to a blood volume of fluid over a period of an hour.
But people sometimes forget that cats have a smaller blood volume, typically 60 mils per kilogram, compared to a dog of 90 mils per kilogram. So we need to adjust our volume doses down the way to compensate for that. So we're looking at kind of 10 to maybe 50 mils per kg bolus compared to 20 mils per kilo in a dog. And giving that over sort of 15, 20 minutes.
If that doesn't work, give another incremental bolus, but typically stopping maybe after about three boluses rather than aiming to get up to that total volume of 60 mils and just monitoring their parameters and assessing for blood pressure coming up, heart rate coming up, as well.
[00:11:55] Gómez-Mejías: That was actually my next question. So thank you so much for participating.
Yeah, I was reading the review. I was taking notes because I found it very practical.
I always read these things. I've been practicing for over 20 years. I always forget all the numbers. And so I was taking notes of it and, and thought, okay, so way to remember it quickly when you're in a, in a moment of stress is like, I think the last WSAVA guidelines on intraoperative intravenous fluids and cats was 3 mls/K per hour or something like that, then you would reduce it, if I'm not wrong. So I thought, well, shat she's saying is like approximately 4 mils per kilogram per hour.
So sorry, but given in 15 minutes and then you do that three times.
Well, three times if you're doing 10 mils per kilogram, or two times if you're doing 15 mils per K. Because the maximum you recommended in the review was a sort of if you don't see any changes, but when you've already infused those two.
[00:12:59] Reed: Because sometimes what happens is your bolus does improve things, but it's not sustained, you know, and you may find after an hour, blood pressure is starting to decline again because that fluid has redistributed out of the vascular system into the, into the tissues. So you're probably fine at that point to give another bolus. You know, that patient has been fluid responsive. But if after 30 mils per kilo, the patient hasn't been fluid responsive and blood pressure isn't coming up, then that's where you need to be thinking about other things, such as inotropes, for example, or Noradrenaline, just to try and get that blood pressure up, rather than continuing to give your fluids.
[00:13:39] Gómez-Mejías: And continue with the with the heart when, when a cat presents in shock, what point of care tools can help us quickly rule cardiac disease in or out before we reach for the intravenous fluid?
[00:14:02] Reed: Yeah, so I, I think the ultrasound is emphasized a lot by emergency care practitioners, and obviously they get very good at doing TFASTs and evaluating some of the more unusual signs, like shred signs for pneumonia. I think for your average practitioner who maybe isn't doing a POCUS two, three times a day, these more subtle things can be challenging. But I think the right parasternal view to assess the size of the left atrium is a very good starting point because if that left atrium to aorta ratio is enlarged, it's fairly easy to get that view, it's fairly easy to measure it. And that is an indicator, if it's more than 1.5, that you need to be kind of cautious with your fluids because heart failure could be contributing here. And certainly if you've got pleural effusion, you also have to be a wee bit cautious with your fluids until you've established whether that pleural effusion is cardiac in origin or, or some other cause. Arrhythmia, generally, you're maybe going to get an indication from your auscultation. Murmurs are not always easy to find, and not all cats in heart failure are going to have murmurs as well. You can't entirely exclude it. You also obviously are thinking about aortic thromboembolism, in which case you're evaluating your pulses and your limb extremities.
So, yeah, I think the category that's maybe a little bit more challenging is the pleural effusion cases, because what I would probably do in those cases is maybe be a wee bit more judicious with my fluids until I've drained the chest, got an idea of what that fluid is, and potentially evaluated whether that could be cardiac in origin. Obviously, if you're getting turbulent fluid out, then that's unlikely, but if you're getting a modified transudate, again, that's where you want to pay a bit closer attention to your heart. And if you do have the proBNP test in house, I quite often will use that. If I'm on at the weekend and I haven't got a cardiologist available, I'll use that just as a little bit of backup to convince myself that it isn't cardiac in origin That's how we use one, if you're not confident about ultrasound as well.
[00:16:23] Gómez-Mejías: That's very reassuring because nowadays you feel like you have to be an expert on ultrasound almost because you have the ultrasound available and it's like especially junior vets are so keen on using it, and me too. Obviously it saves lives. You know, it's very helpful.
You can have it on the side and it's very helpful, but at the same time it kind of. You feel the pressure of having to interpret every single image. So what you've said about I think the other thing you mentioned in the review was the B lines, the beta lines.
[00:16:59] Reed: So these are like hyperechoic reverberations that you see when you're evaluating the lung tissue. It's a kind of bright parallel line that reverberates down and you will commonly pick up maybe two or three when you scan the thorax. But if you're picking up more than that, it does suggest what we call wet lung, which can commonly be associated with pulmonary edema. But you can't rule out that that isn't also associated with inflammation in that lung as well.
[00:17:33] Gómez-Mejías: Yeah, there are other differentials. So it's much more, much more practical to assess the aortic. The left atrium aortic radio for sure. So thank you for that tip.
Let's pass on to sepsis, which can be subtle in cat. Which clinical parameters should make us suspect a cat is septic rather than just in severe dehydration?
[00:18:01] Reed: Yeah. So I think these are the patients that often don't respond to fluid resuscitation.
We've effectively got a kind of distributive shock. So we've lost tone in the blood vessels. So although you're giving a good volume of fluid, often that is not restoring your blood pressure and it can actually leak out of the vessels and start to build up in the. In the interstitial tissue. And that is a challenge actually, in terms of assessing when you have over hydrated these patients, we're often seeing a poor response to food resuscitation.
We've got our hematology, we can see neutrophilia, but we can also see neutropenia. And I think there we need to remember that when we get neutrophilia in cats, it's rarely as marked as we get in dogs. So I've seen dogs put their neutrophils up to 80 to 90 times 10 to the thousand.
We frequently will get values of 30 to 40.
With a cat, it's much more subtle. You know, if I get a neutrophil count of kind of 20, 22 in a cat, to me that that's quite significant.
And similarly, in a peracute stage, we can get neutropenia because the neutrophils have all migrated to the septic focus.
And then there is the challenge of identifying where is that septic focus and what samples do I need to take.
But we also rarely get the pyrexia, the that we will see in the dogs. As I mentioned earlier, the cats tend to do hypothermia.
So you have to maybe rely a little bit on your history at this stage. You know, has the cat been unwell for a couple of days? Has it shown any evidence of urinary problems? For example, has it had difficulty breathing for a couple of days? That might suggest a pyothorax, for example, could it have eaten anything that might have penetrated and given you a septic abdomen as a result of intestinal rupture, for example?
The problem that you have is in terms of trying to get your investigations done to identify where your septic focus is can take a good couple of hours, maybe even longer. And some of them you can't do until your patient is, is stabilized.
So I think, you know, if you do have a little, any kind of suspicion of sepsis, this is where you're playing a balancing act between the antimicrobial stewardship of not using antibiotics unnecessarily versus the sepsis guidelines, which, you know, in people, the surviving sepsis guidelines show that there can be a significant worsening of sepsis if you delay starting antimicrobials.
And then also if I start antimicrobials, is that going to affect my ability to get a diagnosis in terms of culture results?
So it very much is a little bit of a challenge. But I think if you've got a very sick cat in front of you, you potentially have very little to lose in terms of giving some intravenous amoxicillin-clavulanate or cefuroxime, for example, maybe some metronidazole, at least to buy you some time for an hour or two while you try and figure out what is going on with that patient.
[00:21:17] Gómez-Mejías: That's very helpful too, because nowadays the use of antimicrobials is also very challenged due to all the new approaches of the new regulations. Thank you for that. I was thinking you were talking about the neutrophilia and how it's different from dogs than cats are stoic, even in the way they reflect their health status on the blood. Because it seems like you have to take more seriously any increase in the few parameters. Like ALT if you see a dog, it's. Oh, if it's in a cat, like, you have to pay attention to it. If it's the neutrophils, it's like, it's so funny, isn't it, how their external behavior can translate to the interpretation of the bloods.
[00:22:02] Reed: The other thing, it isn't in the article, but we should remember that bilirubin can be a marker of sepsis as well, because, you know, we often think of bilirubin as just being an indicator of gallbladder or biliary pancreatic disease, liver disease. But actually what happens in sepsis is the cells, sort of the transporters in the cells effectively get paralyzed by the presence of sepsis.
So it does build up and the movement of the bile gets inhibited and that's why we get elevated the bilirubin. And that's why we can see it with things like FIP, for example, which can also be a kind of form of sepsis as well. So that can be another marker on the blood panels to give you an indication as well.
[00:22:48] Gómez-Mejías: Very helpful marker. Thank you. Going on to respiratory, upper airway noise is often obvious, but for cats with rapid, sallow breathing, how do we differentiate the underlying problems? We.
[00:23:03] Reed: Yeah, so if we've got rapid child breathing, we're either thinking of pulmonary parenchymal disease or pleural effusion, for example, that's restricting the expansion of the lungs. So you can rule out that category quite easily with your focused ultrasound. But if we're looking at pulmonary parenchymal disease, yes, we can get some information from ultrasound, but we've already discussed the kind of challenges of it.
And getting your definitive diagnosis again can be a little bit challenging. So we can look at trying to stabilize these patients again with our oxygen. Butorphanol can be quite good for just calming them a little bit as well, because it is called respiratory distress, because these patients do get distressed by not being able to breathe.
And these are a category where we probably may need to consider thoracic radiographs rather than trying to get a diagnosis from ultrasound.
And I think people do shy away a little bit from anesthetizing these patients where they think sedation is safer. But actually, sedation could be a bit more stressful to the cat who is dyspneic. So I think you can consider anesthetizing them in order that you can get an endotracheal tube in which is going to facilitate their oxygenation, get you some good quality images and get say a bronchoalveolar lavage which may improve your diagnostics.
But if these patients are too fragile to deal with that, then you have to kind of think about what could be underlying this. What are the chances of this being a parasitic infection for example? And you can consider giving them a wormer that's going to cover lungworm. Are they hunters? Could this be toxoplasmosis? Do you need to maybe thinking about adding in clindamycin into that?
Is it viral? And that could be a challenge in terms of getting some information about that because again, you're often just looking at supportive care with those.
Is it severe asthma? So asthma technically is an airway disorder rather than a pulmonary disease.
And the clue to that might be that it's more, you may be getting more of a prolonged expiratory phase as the patient is trying to breathe out against a constricted airway.
So you can consider your bronchodilators such as terbutaline in that situation and potentially steroids.
But I will hold my hand up and say that, you know, we've often had these severely dyspnoeic cases and we don't know what's causing it and we feel they are too fragile and they will often end up getting a murmur. They'll get some steroid and they'll get a bronchodilator and potentially get, get an antibiotic as well. If we don't feel it's cardiac in origin. And you know, a lot of cats that we see as well come in and they've got an antibiotic and a steroid because people are just trying to cover, cover all, all resources for all potential causes. But I would say that hopefully the cardiac aspect can be ruled out fairly easily out of that category of things that could cause parenchymal disease because you're going to have that big left atrium if you've got pulmonary edema causing dyspnea.
[00:26:22] Gómez-Mejías: Yeah, it's amazing how vets have got to manage the flexibility of their tolerance.
Not the flexibility, but we have to be adjusting our tolerance to uncertainty all the time because in this case our uncertainty will be great.
We still have to do something about it.
[00:26:41] Reed: I think, you know, the problem Is that the, if there's pneumonia present, if there's a bacterial pneumonia present, giving furosemide for cardiac disease could actually worsen that because it inspissates that mucus and inflammatory material that's there and makes it harder to be, to be cleared. You could also argue, well, if there's infection there then maybe steroids are going to make it worse. But I think an anti-inflammatory dose of steroids actually may not be that harmful in the case of pneumonia because you have got inflammation there, it's not immunosuppressive, whereas I think that the furosemide could potentially make pneumonia a little bit harder to clear. So I think if you can rule out the pulmonary edema, the antibiotic steroid combination is maybe not as bad as it sounds. But I think lungworm is something that we, we often forget about actually as a, as a cause of, of severe respiratory signs and cancer as well.
[00:27:38] Gómez-Mejías: But there's no quick way to, to rule that in or out.
[00:27:42] Reed: There isn't, you know, often by the time they're stable enough for investigations, if they've had two or three days of antibiotics, we don't often get an answer either.
Yes, I wish there was an easy, an easy test for it. Sometimes we have to just keep the patients alive and just accept that we maybe didn't absolutely get the answer as to what was going on.
[00:28:07] Gómez-Mejías: Yeah, I think that's a very clear goal that we should keep in mind. That's very helpful.
Our purpose in that situation is to keep the patient alive, not necessarily get to the bottom of the diagnosis.
In cats with arterial thromboembolism, what other drugs besides analgesics should we consider to prevent the clots from progressing?
[00:28:32] Reed: Technically we should be using something like warfarins or heparins.
If we don't have the sort of clot-busting streptokinase-type drugs which, let's face it, few of us do have in the timeframe that we have.
Because these are arterial clots, drugs like warfarin and heparin may be more effective at breaking down the clot rather than clopidogrel and rivaroxaban, which may be more appropriate for venous thrombosis.
However, these drugs, particularly warfarin, are very, very challenging to manage in terms of dosing accurately because obviously if too higher doses given we have very serious consequences of excessive, excessive bleeding.
You know, heparins, the low molecular weight heparins, when they first arrived, everybody thought that they were going to be better than unfractionated heparin. But what was shown was that there can be quite an individual dose tolerance with them. So that. So it was really difficult to know what was going to be the ideal dose for that patient without monitoring.
And the monitoring that we needed to do was antifactor 10A, which is not really readily available. I know Cornell do it, but I'm not actually aware of a lab in the UK that does it.
So we tend to use these antiplatelet drugs instead.
So clopidogrel and rivaroxaban have found sort of favor over aspirin, again because they do seem to be a little bit more effective, shall we say.
Initially there was thoughts about combining aspirin and clopidogrel. We're now moving towards combining clopidogrel and rivaroxaban.
The challenge, as always, is getting doses particularly of rivaroxaban small enough that can be tolerated by cats. Because I'm not aware of compounding pharmacies offering them as yet.
They're not particularly quick acting, although we probably don't want them to be particularly quick acting because then we could end up with issues of reperfusion issue problems and, you know, high potassium as a consequence of that. It's more about preventing the clot from getting worse, allowing collateral circulation to evolve, just trying to let the cat's body deal with the clot that is there and try and buy them some time if you like, while that happens.
[00:30:59] Gómez-Mejías: Yeah, well, thank you. Very, very useful advice as well.
A last question to finish with this first part of your review series.
When we think of a transfusion, when we think that transfusion may be needed, how should we interpret the PCB and the hematocrit valleys?
[00:31:23] Reed: Yeah. So I think we have to look at two things. We need to look at the figures and we need to look at the cat because it isn't always an absolute value. It can depend on how quickly that has happened. You know, some cats who say, have been hit by a car and their PCV has dropped quite dramatically within a matter of hours.
It may not have dropped that low, but if it has gone down from 40% to 20% in two hours, that cat hasn't had time to adapt from that and will potentially be affected by it more than a cat who has, say, a non regenerative precursor haemolytic anemia and their PCV has dropped from 35 to 15 over a period of 2, 3 months.
That 15% sounds like it maybe needs a transfusion, but that cat is probably coping with it quite well. Whereas the cat sitting at 20 isn't coping so well because it hasn't had time to adapt with that. And that can be things like upregulating release of oxygen to the tissues from the red blood cells.
So we need to look at things like what's the heart rate doing, what's the respiratory rate doing, what's the mentation doing to decide whether or not that patient is clinically compromised by it. If we've got an acute blood loss situation, some of those signs may just be due to perfusion and hypovolemia and you then need to reassess them once they've had some fluid resuscitation and see what's happening there.
So it isn't as clear cut as this cat's PCV is at 14%, it needs blood. This cat's PCV is at 15%. It'd be fine. You need to take on board what the cat looks like as well.
[00:33:14] Gómez-Mejías: Nikki, thank you so much for writing this very practical review. It's very reassuring to know that even with limited resources, a calm, methodical approach can make a world of a difference for these patients.
I would also like to thank our listeners and suggest you check our part one of Nikki's review in the Journal of Feline Medicine and Surgery. In July, we will have the opportunity to discuss part two. We will tackle blocked cats, fissures, kidneys and diabetes. See you there.
[00:33:44] Conclusion: Thank you for listening to this episode of All Cats Considered. We hope you enjoyed this interview. For more information on the topics discussed in this episode, please head over to catvets.com/podcasts and explore the links in the show notes. Don't forget to subscribe to this podcast on your platform of choice so you won't miss any episodes as we release them. Have thoughts or ideas about the interview you heard today? Share them with us by leaving a comment on our Facebook page or shoot us an email
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