Medicine

Dr. Andrea Eriksson De Rezende, veterinary cardiologist, joins Dr. Andy Roark to discuss a cardiology case. Dr. Roark has an 11yo FS chihuahua with a grade V/VI systolic heart murmur that needs a dental cleaning. The patient is reportedly starting to cough at home. Dr. Roark wonders if this patient is safe for anesthesia and what sort of diagnostic workup and treatment plan would be appropriate. Dr. Eriksson lends her expertise!

This episode is brought to you by CEVA Animal Health.

LINKS

Explore Free CE from Ceva: https://www.cevaconnect.com/ce/?utm_source=TheConeOfShame&utm_medium=podcast&utm_campaign=Susanne_cardio

Cardalis Info: https://www.cevaconnect.com/cardiology/products/

Skyline Veterinary Specialists: https://skylinevetspecialists.com/

Email: andreaeriksson@skylinevetspecialists.com

Dr. Andy Roark Exam Room Communication Tool Box Team Training Course: https://drandyroark.com/on-demand-staff-training/

Dr. Andy Roark Charming the Angry Client Team Training Course: https://drandyroark.com/charming-the-angry-client/

Dr. Andy Roark Swag: drandyroark.com/shop

All Links: linktr.ee/DrAndyRoark

ABOUT OUR GUEST

Dr. Andrea Eriksson De Rezende is a native of Eugene, Oregon and completed her undergraduate studies at Willamette University in Salem, Oregon. She received her veterinary degree from Oregon State University in 2005, which was followed by a one-year rotating small animal and surgical internship at Oregon State University. She then completed a three-year residency in cardiology at North Carolina State University. Dr. Eriksson De Rezende became a Diplomate of the American College of Veterinary Internal Medicine (Cardiology) in 2009. Until mid 2011, Andrea was an assistant professor of cardiology at Virginia-Maryland Regional College of Veterinary Medicine. Andrea then moved to Brooklyn, NY to join the Veterinary Emergency and Referral group. Currently, Andrea is managing partner at Skyline Veterinary Specialists in Matthews, NC. Her research interests include management of congestive heart failure with particular interest in the renin-angiotensin-aldosterone system as well as cardiac imaging. Personal interests include cooking, travel & singing.

EPISODE TRANSCRIPT

Dr. Andy Roark:
Welcome everybody to the Cone of Shame Veterinary Podcast. I am your host, Dr. Andy Roark. Guys, I got a great one today. I am here with my friend, Dr. Andrea Eriksson. Andrea is a boarded veterinary cardiologist in Charlotte, North Carolina. Man, she’s a wealth of information. I am super happy to have her here to talk to her about a case.
I have a little bitty, itty bitty… Pepita is an 11-year-old chihuahua who’s got a grade 4 heart murmur. And, owner’s report, she’s having a bit of a cough. Well, you’re not going to believe this, this 11-year-old chihuahua has got some dental disease and is really going to need a dental prophy here.
And I’m having some concerns about putting this pet under anesthesia. I’m wondering, “How safe is this? How do I need to work this up? Is it time for some medical management for Pepita beyond what she’s been getting?” Dr. Eriksson walks me through everything. So, guys, this is a quick, action-packed, pearl-packed, little episode that, let’s be honest, you’re going to see this case and you’re going to want to know what to do.
So, anyway, we get into that. We talk about a new drug called Cardalis, which you may or may not be familiar with. But, anyway, it’s great. We’re going to learn a lot. Let’s get into it. Gang, this episode is brought to you ad-free by CEVA Animal Health.

Kelsey Beth Carpenter:
(Singing) This is your show. We’re glad you’re here. We want to help you in your veterinary career. Welcome to the Cone of Shame with Dr. Andy Roark.

Dr. Andy Roark:
Welcome to the podcast, Dr. Andrea Eriksson. Thanks for being here.

Dr. Andrea Eriksson:
Oh, thank you so much for having me. I’m very excited to be here.

Dr. Andy Roark:
Yeah, it’s my pleasure. For those who don’t know, you are a boarded veterinary cardiologist. You are right up the road from me. You’re in Charlotte. You and your husband own Skyline Vet Specialists, where he’s an internal medicine specialist and you are a cardiologist. And then, you guys also have an emergency practice. Is that separate or is that together?

Dr. Andrea Eriksson:
It’s together with us.

Dr. Andy Roark:
Oh, wow, okay.

Dr. Andrea Eriksson:
Yep, I know, I know.

Dr. Andy Roark:
That’s amazing. All right, wonderful. Well, I am so glad that you’re here. I have a case that I want to work up with you. Is that okay?

Dr. Andrea Eriksson:
I love it.

Dr. Andy Roark:
Good, good, good.

Dr. Andrea Eriksson:
It’s my favorite.

Dr. Andy Roark:
Okay, here we go.

Dr. Andrea Eriksson:
Yeah.

Dr. Andy Roark:
So, I have an 11-year-old female spayed chihuahua named Pepita. I’ve had pepita for a while. She has got a heart murmur. It’s grade 4. I can hear it on both sides of her chest. It’s pretty significant. When I hold her in my hand, I can’t tell if I’m imagining that I can feel it, or it’s really… Is that her natural tremble? Anyway, so it’s about that. It’s not a tiny little murmur. But, she’s always seemed to be spry. Let’s be honest, her feet never touch the ground. Mom doesn’t put her down.

Dr. Andrea Eriksson:
As it should be.

Dr. Andy Roark:
Exactly right, as it should be. She gets carried around. She’s coming due for a dental cleaning. We’re going to need to make that happen. And she’s 11. And mom has mentioned to me that she’s doing a bit of coughing at home. Now, I’m not hearing coughing on the exam, but mom says that she coughs at home sometimes.
And so, what I’m coming to you with is this, is first of all, she’s not being medicated right now in any significant way for her heart condition. How do I look into that? I guess that’s the question. Coming up on a dental, are you terrified of this? Are you saying, “Don’t do this dental, Andy?” Or are you saying, “Why don’t you send this to me and I’ll do this dental?” Help me start to look at her holistically of what does medical management look like? What does risk assessment look like? Is anesthesia even possible? How concerned should I be? So, let me just hand it to you like that and say, Dr. Andrea Eriksson, how do you treat that?

Dr. Andrea Eriksson:
Yeah. So, I would say the most practical approach would be is that we’ve got to, like you said, we’ve got a little chichi that is living her normal life, doing her normal things at home. Probably the owners, at this point, are unaware of the fact that there’s things that we can look for at home, that going forward we can look for, in addition to a progressive cough or a change in cough.
That being said, if Pepita’s going to be anesthetized in her relatively near future, just because that’s what needs to have happen because she’s not eating as well or she’s definitely feeling the effects of having pretty significant periodontal disease, then it’s definitely not a no-go for her to have anesthesia. It’s truly on your physical exam, too, everything that you’re going to look at anyways, is that you’re going to be looking to see does she still have a sinus arrhythmia?
Now, that being said, our chihuahuas can definitely have a heart rate of 160 beats per minute, just because they’re there in the hospital in your hands and not at home. But, one of the things that we do tend to look for is that, as a dog progresses into more significant heart disease, their heart rates tend to actually increase just because it is a natural tendency of the heart to try to compensate to increase cardiac output.
But, the things that you can do, and that would be strongly advised for this particular patient, one, first and foremost in your hospital, would be to do thoracic radiographs. And so, making sure that we’re getting a vertebral heart size that, for that particular patient, seems reasonable. So, that number generally is around 10 for a vertebral heart size. It does vary a little bit between having a barrel-chested dog versus a little skinny thin-chested dog. But, in general, somewhere around 10 is about right.
Then, if we’re seeing something, you’re getting a vertebral heart size that is basically 12 to 13, you actually, at that point, it doesn’t mean you can’t anesthetize them. It just means that patient does need to go onto cardiac medications. And so, we’re thinking, at that point, especially if we interview the owner and the owner is saying, “No, I don’t really see any exercise intolerance or restlessness at night,” if they were savvy and looked up maybe, “What I should be looking for in my pet that maybe has a heart murmur,” if they knew, then they might look up, “sleeping respiratory rate”. It might come across somewhere in their Google search. And so, if they were savvy enough to say, “Hey, no, I’ve done this and it’s consistently below 30 breaths per minute,” then you thankfully have another piece of information. But, many owners don’t know that they need to do that yet until you tell them to do that.
But, say, if that vertebral heart size is 9.7, then that murmur, due to that leaky valve, is not causing any sort of cardiac decompensation at that point. And so, those are patients where you could feel pretty certain that if you use basically your protocol that you would normally use for an 11-year-old dog… So, you’re not going to wallop them with a bunch of medications that are going to change your pressures and their heart rate rapidly.
You’re using things like your midazolam and torodent for your pre-med. And you’re using something like propofol, alfaxalone for your induction. And putting them on a relatively normal rate of isoflurane with your normal five ml per kg per hour type of fluid rate. You’re going to be good.

Dr. Andy Roark:
All right. So, let me say this back to you. So, it’s funny. Yeah, I’m surprised, I think, at how much weight you put on the vertebral heart size. That’s a pretty significant line for you to go to, it sounds like. So, first of all, let me just say, real quick, can you give me a refresher on vertebral heart size just for people who are not familiar, who haven’t been in that position to use it before?

Dr. Andrea Eriksson:
Absolutely. So, it is basically a sum. So, on your right lateral thoracic radiograph, you’re basically going to take a… You can just use a piece of paper, too, where you’re going to take a line, and make a line, and measure this line from the carina down to the apex of the left ventricle. And then, you’re going to do a perpendicular line from the cranial edge of the cardiac silhouette to the caudal edge of the cardiac silhouette just underneath the caudal vena cava. Because you do want to be measuring the ventricles. You don’t really want to get the atria up in there.
So, you’re going to take those lines and you’re going to superimpose them over the thoracic vertebrae. And you’re going to start that line, the very beginning of that line, at the cranial edge of thoracic vertebra number four. And so, you’ll put that line. And then, the second line, which is that perpendicular line, same thing. Start at the edge and start measuring from thoracic vertebra number four, cranial edge. And you’re going to count how many vertebral bodies are in each line, basically, and you add that up. And so, that’s where you’re going to get that.
It’s one of those things that I have plenty of slides showing that. So, if anybody wants to reach out to me, I can shoot them an email super quick and easy. But, there’s plenty of resources out there, too, that show you that way of doing it, but that’s what…
And it’s one of those things that, yes, I get referred these cases all the time for me to echo. And it gives me additional information about that patient for sure. It gives me much more specific information. But, when we’re talking about you having to see 60 patients in a day, and you have 15 minutes to talk to an owner and say, “Hey, I’ve got to figure out if I can take out these teeth because they’re really bad,” that would be the thing that that family veterinarian could do within their hospital to get basically some really good information about that patient.

Dr. Andy Roark:
Yeah, that makes sense. Talk to me a little bit about what you’re looking for with a sleeping respiratory rate. So, I love the idea of getting the pet owner involved in this so they can look at it. Are you looking for trends here or are there certain… You mentioned 30 breaths per minute. Is there some sort of number that starts to give you pause? Walk me through how you use that tool.

Dr. Andrea Eriksson:
Yeah. So, I would say that getting them involved is key. Basically, I talk to my owners about having a triangle of care, which is myself, them being most important with their pet, and then with their family veterinarian. So, that way we can all have a good conversation about what’s going on with Pepita at home. And so, one of the things I’m talking to them about is, “Hey, what we have known about this over the past 10 years is that if we’re able to, whether you do it on an app, so there’s a number of apps, Cardalis has an app, but you basically can track what their sleeping respiratory rate is.” So, I talk to them about, “Hey, if you can get them while they’re completely passed out asleep, just absolutely snoring and sawing logs, then you’re going to watch a rise and fall of their chest, and that’s one breath. They should be, while they’re sleeping a good… nobody having any issues with their heart or anything, they’re going to have a sleeping respiratory rate that’s less than 30 breaths per minute.” Now some dogs, you just can’t catch them while they’re asleep. They know you’re stalking them.

Dr. Andy Roark:
Yeah. They crack one eye open. Yeah.

Dr. Andrea Eriksson:
They’re like, “What are you doing? You’re a creep.”

Dr. Andy Roark:
Yeah. Got you.

Dr. Andrea Eriksson:
So, yeah, they’re like, “You’re a creep.” And so, we allow those guys to get up to 40 breaths per minute because they’re going to change a little bit and fluctuate because they’re creeped out by you. Yeah, yeah. So, that’s what I’m looking for. Trends are amazing. So, if I have an owner that can give me at least data points of three to four per week, that’s like music to my ears. But, it is something I tell my owners that, “When I call you, I’m going to bug you, and I’m going to ask you what this number is, and it’s going to be annoying, so just if you do it will be less annoying.”

Dr. Andy Roark:
I bet they love it. I mean, I bet they love it. It’s something that they can actually-

Dr. Andrea Eriksson:
Yeah, because it’s involved.

Dr. Andy Roark:
… do and feel like they’re involved. Yeah, exactly. I think a lot of times the hardest part with disease, whether it’s you or whether it’s your pet, is a feeling of powerlessness. And so, just the ability to be like, “Yep, I am taking action here,” I think that that’s such a healthy, good thing. So, I love this. I’m on board with the vertebral heart score. I’m with the resting breathing rates. So, I’ve got Pepita here, and let’s say that she’s trending a little bit high, so her vertebral heart size is a little bit greater than 10, maybe up 10, 10 and a half maybe. I’m like, “I don’t know. We’re kind of on the far side of this.” How you do you start to manage that case?

Dr. Andrea Eriksson:
I would say veto. 10 and a half might be a little… We’d be still within a normal range. But, if we bump that up a little bit, say 11.3 or something, and on addition to that you’re starting to see maybe that little hump of a left atrium that’s up next to your mainstem bronchus, and you’re like, “Yeah, that looks a little bit big.” Then, those guys, I typically will say, “Hey, we need to put your pet on Vetmedin, on [inaudible 00:13:49] going to start [inaudible 00:13:50].

Dr. Andy Roark:
Now, we’re going to lay there and make them lay down. Yeah, exactly. Put a box underneath them.

Dr. Andrea Eriksson:
We’re going to have to put you on the box. I wish it worked that way. What we do know about patients that have mitral valve regurgitation due to chronic degenerative valvular disease, and their hearts are getting big, we know that they’re going to live longer and stay within that pretty much asymptomatic period much longer if we get them started on pimobendan.
And so, those patients, I typically will start anywhere from a quarter to a 0.3 mg per kg twice a day Vetmedin dose. It’s well tolerated. There are some patients that may have some GI side effects, so I usually tell them, “Hey, if you see something like that, just try to give it with some food, even though the package insert will say, ‘Give 30 minutes before food.'” It’s like we have to make sure that the patient can tolerate it, and so a lot of them do get it with a little bit of food.
Those are ones where if I have a family vet that’s like, “Oh, Andrea, I need to do that procedure today,” then that’s fine. They can actually have a dose even 30 minutes before they have their procedure because it does work fast. We use it as an emergency drug. So, it does have an effect. If you can wait, maybe having them on it for about a week or so, so that way you actually have that additional support for that cardiac, basically what we’re looking for is increasing the efficiency and decreasing the workload on the heart. So, if we can have it on board before we do the procedure, that’s even better.
And so, some of these guys will get it and they’ll get it about a week before or longer before they go. But, then they stay on it afterwards. So, I usually make that clear. We’re not just using it for the procedure, we’re using it for a long-term. This is going to be something, unless something comes up where the animal doesn’t tolerate it, we’re going to be on this for the rest of Pepita’s life. And hopefully it’s a long life for our little Pepita.

Dr. Andy Roark:
No, I like it. So, great. So, you open up with pimobendan and get them [inaudible 00:15:59]. It’s a miracle drug, in my experience.

Dr. Andrea Eriksson:
Yeah, it is. Yeah. No, it changes things for sure.

Dr. Andy Roark:
Yeah. Well, great.

Dr. Andrea Eriksson:
Yeah.

Dr. Andy Roark:
So, talk to me a little bit about stages and degrees with this case. So, I’ve got Pepita, an 11-year-old chihuahua, I’ve probably got a long way to go. We’re going to start out with management in this regard. She mentioned she’s got a cough at home, things like that. Are you thinking about a diuretic of some sort? Are you not? Are there triggers that are going to send you into action in that regard? Help me walk in that direction, if you don’t mind.

Dr. Andrea Eriksson:
The time where we’ll definitely say, “Okay, we’re going to need to start a diuretic,” is, whether it’s somebody who feels very, very comfortable with thoracic radiographs and say, “Oh, yeah, I actually do see…” Typically, on a radiograph, what we would see is venous distension.
So, on the lateral radiograph, you have an artery, a bronchus, and a vein, and those guys you can see pretty clearly in that cranial thorax. If you do a left lateral, what’s nice is that vein will pop out a lot easier. So, if you do a right lateral… I typically do DV so I don’t have to put them on their back and then I’ll also do a left lateral. The left lateral just shows up that vasculature to that cranial thorax just a little bit better. So, you can compare that vein to that artery.
And so, having a vein that’s plumper, bigger than that artery, that concomitant artery, is an indicator that we’ve got some kind of… that heart’s having a harder time handling its preload, or basically the volume that it feels that’s coming into it. Then, you’re going to be obviously looking for any sort of pulmonary pattern that’s more of a interstitial alveolar pattern. And that pattern, typically in our dogs that have mitral valve regurgitation due to degenerative valvular disease, it usually will start in the right caudal thorax. And so, if you have that DV or VD, and you look in that right caudal thorax, that’s usually where they start to dump the fluid. And so, I typically tell my family that, “Hey, if you can get that view, it’s extremely helpful for us to be able to tell if there’s edema there or not.”
Those patients, if we do see that, and we’re worried about that, and even if they come in and maybe the owners haven’t really… They’ve maybe noticed a cough, but you listen, and you’re watching the dog breathe while you’re talking to the owners, and you’re like, “Well, he’s kind of using his belly to breathe a little bit, too, in addition to those clinical signs,” and owners say, “Oh, yeah, I have kind of noticed that. Anything, from when Pepita tries to run up the stairs, we kind of have to stop and breathe kind of heavy, and I just thought Pepita is getting older. We know that.” And it’s like, “Well, it’s not just getting older. Unfortunately, we need to start some more.”
So, that’s when I will definitely say, “Hey, we’ve got a constellation of clinical signs and radiographic features that do support a diagnosis of congestive heart failure. So, that takes you into, from stage B2, which Pepita would’ve been at before, where she just needed Vetmedin, to stage C, which is basically congestive heart failure. And it may be early stage C. We’ve got a little bit of clinical signs going on. It’s not an animal that’s rushing into the ER, but we’re starting to see those features of edema as well as clinical signs at home.”
So, those patients, we’re going to start them on furosemide typically. So, Lasix. A little chihuahua that is 4.5 kilograms, and is showing us those types of more subtle signs of edema, but we’re convinced this is edema, that little one is going to probably get somewhere around 6.25 milligrams twice a day of Lasix. You might think some, if they’re a little bit more clinical, and you’re listening and the lungs don’t look great, you may start with a little bit higher dose. You might go one full 12.5 milligram tablet twice a day for a little bit and then back down to a half a tablet.
If we’re starting that, then you do need to start something that inhibits the activation of the renin-angiotensin-aldosterone system. What we do know now from recent studies, and this came out a couple years ago, is that dogs will live longer, in addition to having the Furosemide on board and the vetmedin onboard, is also inhibiting the renin-angiotensin-aldosterone system. That’s best done with both an ACE inhibitor and also a mineralocorticoid receptor antagonist too. So, that would be your spironolactone.
So, I usually will say, “Hey, I know it’s a lot of drugs, but your dog’s going to live longer if we get them onto the a lot of drugs.” So, there’s a number of ways of doing that, whether it’s separating them all out where you have Lasix, vetmedin, spironolactone, and an ACE inhibitor. So, that can be your prils. So, whether you like enalapril or benazepril. Personally, this is just… I like Benazepril because it’s once a day. And so, you can get spironolactone and benazepril together and cardalis. And basically you’re going to dose the cardalis based upon the spironolactone dose that you want, which ends up being around two mg per kg. So, for that spironolactone dose. So, that ends up being about two mg per kg for spironolactone and then a quarter mg per kg for the benazepril in that dose.

Dr. Andy Roark:
Talk to me about cardalis. Just talk to me because there’s a lot of people that haven’t used it yet. They don’t have it on their shelf yet. Just give me a high level overview of cardalis as a medication, and when that plays in, and just the benefits that you see in it.

Dr. Andrea Eriksson:
Yeah. So, the benefits that I see is, honestly, what I tell my owners, backed by studies, which is really nice. There are times where I have to say, “There’s this drug, hopefully it helps.” But, I’m not your cardiologist that really likes to do those things. I love having data behind it. What’s nice about cardalis, is it does have that data. And so, their studies show that if you use the combo of spironolactone and benazepril together, it was better than benazepril alone.
So, a lot of family veterinarians feel like, “Oh, I know Andrea. I know we use the vetmedin. I know we use the Lasix.” And then there’ll probably be 50% of them that say, “Okay, I feel comfortable using the ACE inhibitor.” Now, I’m hoping that people will feel more comfortable with also layering in the spironolactone. What’s nice about the cardalis is it is one pill. And so, Pepita, she would probably get 20 milligram and 2.5 milligrams. So, 20 milligrams of spironolactone, 2.5 of benazepril. And I would probably start her on about half a tablet once a day. And then, they’re done with that drug drug.
So, it’s nice just because you just have it and you don’t have to say, “Here’s two other medications,” remembering which one is which and when. And what’s nice about it, too, is that that’s the actual drug that was studied. So, there’s a lot to be said about saying, “Okay, this is what was actually studied versus other combinations.” And so, when I talk to them about things, I’m like, “If it’s me and my pet, I want the one that was studied.” And then, they did all the safety data to show that there’s… I mean, it’s more than unlikely. It’s really not going to happen where you’re going to worry so much about them becoming hyperkalemic.
So, a lot of people think, “Oh, God, Andrea, if I use both of them together, their potassium’s going to be nine.” It’s not going to happen. And so, if you are worried because you did prelim blood work before you started it, and their potassium’s 5.2, and you’re like, “Oh, God, if I get up to six, it’s going to be terrible,” then start them at a lower dose. And then, just recheck them, because you’re going to recheck them anyway because they’re in heart failure. So, that’s what I typically will… that’s what I recommend in counsel to my owners.
And when they talk to me about the cost, it’s a real thing because it is more expensive than you go into the Publix or Harris Teeter pharmacy and picking out the two. I talk to them like, “Well, this is what was studied though.” So, if it comes down to it that the cost is a really big deal, then okay, but I’m going to tell them what I recommend.

Dr. Andy Roark:
Yeah. No, that totally makes sense.

Dr. Andrea Eriksson:
Yeah.

Dr. Andy Roark:
Talk to me about monitoring of this case. So, you said, “We’re going to recheck it, we’re going to follow up because they’re in heart failure.” What does follow up for you look like in a case like this?

Dr. Andrea Eriksson:
Yeah. So, ideally what I will do, if the patient comes to me, when I see them back, I usually see them back somewhere between seven to 10 days after we’ve started all these medications. Now, the caveat to that is a patient that I’m a little bit worried. So, instead of Pepita maybe being 11 with normal renal values, I feel comfortable going seven to 10 days, even a couple of weeks before I recheck her.
And when I’m rechecking, it’s just I’m rechecking blood work. So, in particular, I want to know what her [inaudible 00:25:56], her creatinine, and her electrolytes are doing. And I check their blood pressure. So, for me, I’m a little bit crazy about checking their blood pressure. But, I check with the Doppler just because I’m making sure that there’s no extra workload on that cardiac muscle. So, yes, I worry about them getting hypotensive. But, I really do worry about them getting hypertensive. And their hypertension is not because they’ve got heart disease, it is because they can develop, just from RAAS activation, them having… them developing hypertension.
Then, you’ve got dogs that are 13, 11 that can also have things like Cushing’s. They have other things. And so, I’m making sure that I’m doing everything I can to unload that heart as much as I can. So, those are the two things I like to get at is their blood pressure and their, whether you call it a renal panel or whatever you use at your clinic.
If I have a patient that I worry that their creatinine’s on a little high end of normal, then I will see them five to six days. I won’t go… It’ll be like I’ll cut out half that time. I need a good five days for the drugs to actually have their desired effect, but also have truly when they get good blood concentration. So, we know that about five days, especially with the ACE inhibitor, is going to be a good landmark for us to be able to say, “Now I can see truly what you’re going to be doing with the ACE inhibitor and the spironolactone at that point.”

Dr. Andy Roark:
Dr. Andrea Eriksson, you are amazing. Thank you so much for being here and helping me with this. I really appreciate it. Where can people find you online? Where can they learn more from you?

Dr. Andrea Eriksson:
Yeah. So, if you just look up Skyline Veterinary Specialists in Charlotte, North Carolina, because we’re a small clinic, you just hit the Contact Us, it basically goes to me. But, you can also andreaeriksson@skylinevetspecialists.com.

Dr. Andy Roark:
Excellent.

Dr. Andrea Eriksson:
Yeah.

Dr. Andy Roark:
Perfect. Thank you so much for being here. Guys, thanks for tuning in. And that’s it. That’s our episode, guys. I hope you enjoyed it. I hope you got something out of it. Thanks again to Dr. Andrea Eriksson for being here and lending her knowledge. Thanks to CEVA Animal Health for sponsoring this and making it possible. Gang, be well. Take it easy. To talk you soon.

In this Hall of Fame Episode: Join Dr. Roark and the wizard, the legend “Uncle Mickey Schaer” as they talk about that case that terrifies us all – the venomous snake bite!

You can also listen to this episode on Apple Podcasts, Google Podcasts, Amazon Music, Soundcloud, YouTube or wherever you get your podcasts!

LINKS

Uncharted Practice Leader Summit: https://unchartedvet.com/practice-leaders-summit-2023/

Dr. Andy Roark Exam Room Communication Tool Box Team Training Course: https://drandyroark.com/on-demand-staff-training/

Dr. Andy Roark Charming the Angry Client Team Training Course: https://drandyroark.com/charming-the-angry-client/

Dr. Andy Roark Swag: drandyroark.com/shop

All Links: linktr.ee/DrAndyRoark

ABOUT OUR GUEST

Dr. Michael Schaer received his D.V.M. degree from the University of Illinois in 1970. He then went to the Animal Medical Center (AMC) in New York City where he served as an intern and then as a medicine resident between1970-73. After the residency, he remained at the AMC as a staff member in the Department of Medicine until 1977. He then joined a private small animal practice in New Jersey until late 1978 at which time he joined the faculty at the University of Florida, College of Veterinary Medicine where he has remained until the present time. He has published several papers and book chapters and he has lectured nationally and internationally. Dr Schaer is also the author of five textbooks: Clinical Medicine of the Dog and Cat – 1st, 2nd, and 3rd editions and Clinical Signs in Small Animal Medicine, 1st and 2nd editions. At the U of F, Dr. Schaer functions mainly as a clinician and a teacher. His previous UF professional duties included: Professor and Associate Chairman-Department of Small Animal Clinical Sciences, Associate Chief of Staff-Small Animal Hospital, and Service Chief-Small Animal Medicine. Dr. Schaer served as Interim Chair, Department of Comparative, Diagnostic, and Population Medicine from February 2017-September 2018. He is currently Professor Emeritus and Adjunct Professor in Emergency and Critical Care Medicine, while still doing active teaching in the classroom and in the critical care unit. Dr. Schaer is board certified in internal medicine (ACVIM) and emergency and critical care (ACVECC).

EPISODE TRANSCRIPT

Dr. Andy Roark:
Welcome everybody to the Cone of Shame Veterinary Podcast. I am your host, Dr. Andy Roark. I am back for you. It’s summertime, and that means the snakes are moving around. That’s right. This is the time of year where if you go out in the evening, you’ll see them on the road there. There’s a lot of snakey activity right now, and I recently came upon a copperhead walking my dog and it scared me and it scared the copperhead and my dog was super into it, but that was not helpful. And so anyway, these things happened.
Guys, I did an episode a couple years ago with someone that I just think the world of. He was that guy when I was in vet school, he was the mentor. I think every vet school has got this clinician that is just the clinician that everyone kind of looks up to. And at the University of Florida for a couple of decades, Dr. Mikey Scher was that guy. And so Uncle Mikey, as he’s known to us, Florida grads, came onto the podcast and talked about dealing with venomous snake bites and canine patients. And guys, it’s a great episode, super timely. Let’s get into it.

Kelsey Beth Carpenter:
(singing) This is your show. We’re glad you’re here. We want to help you in your veterinary career. Welcome to the Cone of Shame with Dr. Andy Roark.

Dr. Andy Roark:
Welcome Dr. Michael Scher. Thank you for being here, sir. Really appreciate it.

Dr. Michael Schaer:
Oh, you’re welcome, Andy. It’s a pleasure to be here.

Dr. Andy Roark:
I have a case for you from my … Some of our cases that we like to make are theoretical. This is not. One that I had recently and I want to go with it with you if you don’t mind. I sure have. And I know this is something that you do a lot of in Florida. I had a two-year old Boykin Spaniel, which I never saw in Florida. I never saw it in Gainesville. It’s the state dog of South Carolina, and now I see them all the time.

Dr. Michael Schaer:
Really?

Dr. Andy Roark:
But yeah, very similar to Cocker Spaniel for people who are listening who don’t see a lot of those, but the Boykin Spaniel I see a lot of, and this is a young Boykin Spaniel stuck his nose underneath the deck at the house, barking, head down, tail wagging. Mom brings me the dog and says he got bitten by a snake. And of course, I wait until presentation to decide how excited I’m going to get about this. Mom said on the phone she says a copperhead bit him in the face. It was a small copperhead. And the dog shows up and sure enough, this is, it’s probably been about 30, 45 minutes by the time I see the dog from the time of the bite and the left side of his lip, I can see those two small little draining tracks. I see the punctures and his lip is swollen. Not whole face, but you know what I mean? It’s probably the size of a large grape is the swelling. And I’m getting some ooze out of there.
And so I’m looking at this dog and this copperhead bite and a million things are going through my mind and I’m hearing don’t give him NSAIDs. And then other voices are like, “We’ve got to do something for pain control.” And what is my risk of tissue necrosis here? And then it’s on the lip. And so I’m worried about tissue death there, because it’s a fairly small area. And so I just want to put this to you and say, Dr. “Scher, where do I go from here?” Like I’m looking at this dog, it just happened. I’m thoroughly convinced it was a copperhead based on, I didn’t see the snake, didn’t bring it in. Dad killed it, but it didn’t come along. Well, let me ask this, how do you treat that? Where should I go from here?

Dr. Michael Schaer:
The fact that this is occurring in South Carolina, copperhead is certainly one to consider, but the water moccasin can sometimes extend that far up as well. And even the eastern diamondback in some areas as well. But as far as the frequency of encounter, I would say copperhead is probably the majority up there. The one thing that I try to teach all the time about snake bites, Andy, is that no two cases are the same, okay Because the victim is different and the snake might be different than another copperhead a mile away. Their venom composition might vary, okay? And depending on the pressures of the ecosystem as these animals evolve in nature, but the copperhead in general, it is a pit viper and it contains a venom that is necrogenic. It might not necessarily be toxic, it’s not neurotoxic. So with the copperhead, we worry more about local damage.
Now whether this is going to turn into something that’s just simple edema or some focal hemorrhage with edema, it might stop there. If necrogenesis is going to occur, what I have found here in Gainesville with the other types of pit vipers that I deal with, the signs of necrosis usually don’t occur ’til the end of day until around day three. So as long as that lip is spongy and it looks well vascularized, there’s not any change to brownish or blackish or black, there is a chance that the swelling’s going to go away. And as far as the timing of the disappearance of that, it usually starts by day three as well. Where it starts resorting. It might drop a little bit more dependently and then it will disappear. Now, the thing about tissue necrosis, especially with a snake like the copperhead, the tissue necrosis occurs very soon after the bite.
So during that 40 minute car ride, the collagenases and the hyaluronidase contained in that venom allowed that venom to spread, and get a fairly good seating as to whether or not, as far as into the surrounding soft tissues. So what you don’t know when you’re looking at that dog is will this go on to necros? The answer is you don’t know.

Dr. Andy Roark:
Okay.

Dr. Michael Schaer:
I don’t know. And you say that to the owner. So the next thing is, well what about treatment? So when you look at the spectrum of severity for the copperhead, at least in people in that part of the country, they’re usually more local wounds. They get their swelling and they’re out of the ER in maybe three hours. But there are some people who can actually go on to become coagulopathic and they’re the ones who are in harm’s way, and that’s when they start having to take in a whole bunch of anti-venom. Now, it is going to be up to you to decide whether or not you want to give anti-venom, and a lot of that is going to be dependent on the cost, whether or not the owner can afford it. My philosophy is that if there’s the possibility that this invemination can go beyond a minimal localized invemination, I’d rather be proactive and head it off.

Dr. Andy Roark:
Okay. I see.

Dr. Michael Schaer:
And I would suggest one vial of anti-venom.

Dr. Andy Roark:
All right.

Dr. Michael Schaer:
Now something like VenomVet’ll be fine. Or even the Boehringer Ingelheim, the one we used to call Fort Dodge.

Dr. Andy Roark:
Yeah.

Dr. Michael Schaer:
Okay, that’ll work as well.

Dr. Andy Roark:
Okay.

Dr. Michael Schaer:
And the chances at one vial causing anaphylaxis, I would say would be less than 10%. But the chances of that invemination getting worse is probably more than 10%.

Dr. Andy Roark:
Okay. Hey guys, I just want to step in real quick and let you know that on August 19th, my good friend Jen Galvin, who is a practice manager in Arizona and just an amazing, super fun, super funny person, is hosting a virtual workshop at the Uncharted Veterinary Conference. She’s doing her workshop called How to Have Fun and Engaging Meetings. Let me tell you Jen Galvin, I have seen Jen Galvin have Nerf gun fights at her practice. She has game shows for staff meetings. She does education in the most fun ways possible. She is so fun. And this is a workshop, which means you’re going to actually get ideas and you’re going to get to work on your own practice and come away with some tangible things that you can take back and do with your team to have fun and engaging meetings.
Guys, this is a great workshop. It is on August the 19th, so that’s coming up next week, from noon to 2:00 PM Eastern Time. That’s 9:00 AM to 11:00 AM Pacific time. So anyway, noon to two eastern time workshop. I’ll put links in the show note for you to register, check it out. It’s also a great way to see what the Uncharted virtual events are like, Uncharted Vet Conference is the conference that I started, I love it. I think that there’s … I don’t know that there’s a better, more fun engaging way to learn than things like this. So anyway, guys, I hope you’ll try it out. I hope you’ll take something back for your practice. That’s it. Let’s get back into this episode.
Can you unpack a little bit about anti-venom for me as far as, is it species dependent, snake species dependent? Because I had sort of thought that obviously I’m in the south, the eastern diamondback rattlesnake is what we really worry about the neurotoxin, as opposed to your more locally destructive bites of your water moccasins and your copperhead, things like that. Does the species of snake play into your choice to use anti-venom or not? And then also you say, go with a single vial. Is that size dependent on the patient at all? So if you could unpack a high level of anti-venom thought right now, I think that would be so helpful.

Dr. Michael Schaer:
Okay. There are a few types of anti-venoms available to us in the United States. We have VenomVet that’s made in Argentina that’s made from the South American, and I think the Central American pit vipers. VenomVet two is coming out, and when it gets cleared, it’ll be made from the venom of local snakes and then in North America. But the VenomVet that we use now comes from pit vipers from south of the border. The reason that it works for our snakes is because the pit viper venoms in this part of the world, in the Western hemisphere, share antigens. So using an anti-venom that’s against [inaudible 00:11:26] or one of the other pit vipers, that might very well still be effective against the eastern diamondback and the water moccasin and the copperhead.
So that’s good. Now the VenomVet is, and it’s called an Fab2, where the most primitive anti-venom that they used to use in people from [inaudible 00:11:49] has an FAB, an FAB, and an FC component. Remember the stuff is made in horses. So you’ve got the specific ground to air missile, the FAB, but they’re linked together with this FC, which is extra protein from the horse serum.

Dr. Andy Roark:
Okay.

Dr. Michael Schaer:
And that’s what contributes to its anaphylactic genicity.

Dr. Andy Roark:
Gotcha.

Dr. Michael Schaer:
Okay. Now BI or the Fort Dodge product has the FC component RTLR, the new anti-venom that comes in those plasma bags, that’s a large molecule as well. They have a tendency to load more extra antigen and to make the animal perhaps more hypersensitive to it. CroFab we don’t use because of the expense. So what veterinarians are going to use is RTLR, the Ford Dodge product, and the [inaudible 00:12:43]. As far as I’m concerned, they all work. The RTLR might have some extra antigen to it and some people might not want to get involved with that, but it’s still effective against venom.
As far as duration of the anti-venom in the blood, this is where you want your grout to air missile to get into the bloodstream, nuke out the venom protein and hang around for a while. The problem with CroFab, it’s out of there in six hours. The VenomVet hangs around for around 24 to 36 hours. The Fort Dodge product can hang around for as long as 48 hours. So that comes to an advantage to you because when the dog gets bitten by the snake, some of the venom will go into the system fairly acutely while the other amount of venom is deposited at the bite site and then it slowly infuses over the next several hours. Well, if you use a fast acting anti-venom like CroFab, those ground to air missiles will already be out of the sky. But if you use the longer-acting anti-venoms, they’re still there to intercept.
So that’s where VenomVet and the Fort Dodge products will work to your advantage. Now, as far as the dosage of anti-venom is concerned, it’s impossible to specify, for the reason being that we don’t know how much venom is inoculated. So I go by clinical science. The other question that goes along with the choice of the anti-venom is what snakes contribute to the manufacturer of that particular product. The Fort Dodge product is going to use several North American snakes. The VenomVet one, which is what’s available now, uses the South American snakes, but it’s still effective against the North American snakes. So I take advantage of the cross antigenicity.
The RTLR is made from North American snakes. Now the question you asked me, when there are several snakes in one geographic locale, how do you know which snake bit the dog? We can squeeze out of that predicament by using the polyvalent anti-venom. Now in Australia they might use monovalent, in other words, an anti-venom against the brown snake or the tiger snake or the Taipan snake. But they’re getting smarter now in Australia because some of their antigen detection kits might be inaccurate and they’re switching over to polyvalent and just covering the victim with all of them in that area. So here in the US we have traditionally always used the polyvalent vaccine. So like I said before, they all work, they differ in their molecular size, and the choice is going to be up to you as to which product you want to use.

Dr. Andy Roark:
Gotcha. Yeah, let’s go on from there. So anti-venom, your recommendation is much stronger than, I guess what I sort of gave [inaudible 00:15:45]. So I really love that we laid this out. So at least a single vial of anti-venom, I think that makes sense. What other sort of supportive care are we talking about? If it’s three days until I’m going to see signs of necrosis, do I need to have this dog on fluids for 72 hours? I mean, help me with that part.

Dr. Michael Schaer:
As far as the dosage of the anti-venom, that’s going to depend on a scale that we call the snake bite severity score. And that goes from one to 20 and it encompasses various pathophysiological things that we see clinically, whether there’s coagulopathy, neurotoxicity, cardiac arrhythmias, hemolysis. If we see all of those in that one victim, I’m going to start off with several vials.
And I’m going to make it simple. If the animal comes in walking wagging its tail, I might give one vial. If it comes in walking very slowly and it doesn’t look right and it looks like it’s going to get sick, I might start off with two or three vials. Now behind those guesstimates is the snake bite severity score going on in my head. If an animal comes in recumbent and trying to die on me, he’s hypotensive, he’s bleeding, he’s hemolyzing. That dog will probably start off with four to six vials, and then if they’re really severe, we will run an ACT, where normally the ACT is less than 120. If the ACT doesn’t normalize, I might repeat a couple more vials of anti-venom at hour six.

Dr. Andy Roark:
Okay.

Dr. Michael Schaer:
You see what I mean?

Dr. Andy Roark:
Yep.

Dr. Michael Schaer:
Okay. And it just goes on to assess and reassess, assess and reassess until the patient is stabilized. Now with the copperhead, I know a lot of times the animals get better without the anti-venom. You might just give them some fluids and they might get off real cheap and go home and everything’s going to be okay. A lot of practitioners will also use antihistamines and steroids. There’s no evidence-based medicine to show the efficacy of steroids and antihistamines. The only time I use them is when there’s a hypersensitivity reaction to the anti-venom. But if the blood pressure is kind of borderline when it comes in, I’ll give them [inaudible 00:18:08]. We don’t use anti-venom in every case here in Florida either. If I have a pygmy rattler and an animal comes in walking wagging its tail, but it hurts because it got bitten on the paw, we’ll watch it for 24 hours. That’s important.
We keep them in the hospital. If the people have absolutely no ability to pay the bill or anything like that, that’s the only time they will walk out on the same day. But they’re told to come back of course, if there is further decompensation. But I know that close to eight out of 10 practitioners want to use the antihistamine and the steroid. And I’ll give you some clarification on that. It depends on where you are in the world and whose country anti-venom using. If you’re in Pakistan or if you’re in India and you’re dealing with the snake bites out there, a lot of times they’re vipers or cobras. Their products might not be as pure as those products that we use here. And the incidence of allergic reactions are very high.
In those situations, they’ll give the patient antihistamines and steroids initially and then give the anti-venom, but in the western hemisphere, it’s not recommended in human medicine and I’ve convinced everybody here at the school on now hundreds of cases that you don’t have to use steroids and antihistamines, that my cases will get better just as fast as yours if those two drugs are being used. So I leave it, of course, to the individual colleague. If they’re using something that works for them, I don’t want to upset their apple cart. But if they were to ask me for, is there anything to document the efficacious of this, I would answer it in the way I just told you. Okay?

Dr. Andy Roark:
Perfect.

Dr. Michael Schaer:
Okay. Now as far as waiting for necrosis, there are times when dogs will be discharged from here at the end of the second day and it hasn’t actually been long enough for necrosis to make itself known. So we tell the people, look for any signs of discoloration and change in texture of the skin. If the skin changes from pliable to feeling like leather, there is a likelihood that that’s going to necrose. So they could tell, or they could send you a picture on their cell phone or a video and you could make a decision whether or not they should bring it back for debridement.

Dr. Andy Roark:
That makes sense. What is your pain control plan with these patients?

Dr. Michael Schaer:
All right, pain control initially on a severe case is minimal.

Dr. Andy Roark:
All right.

Dr. Michael Schaer:
Because I don’t want to knock them out with drugs when their level of consciousness is helping me decide on whether they’re trying to die or not. And we will use methadone and extend that for maybe the first two days on those who aren’t severe. Or we might, if the severe case comes in, we’ll hold off on the pain control until we get the patient stabilized and then we can monitor them better. But if you have a copperhead doggie that comes in after barking at something under the porch and the paw is swollen and then it’s obviously not weight-bearing and it hurts like crazy, then gabapentin works, methadone works as an injectable. Or you might start off with methadone and send them home on a few days of gabapentin, something like that.

Dr. Andy Roark:
That’s wonderful. Thank you. Thank you for doing this. I really appreciate. This has been so enlightening. Do you have any parting pearls, any last words of wisdom from me as I head off to take care of my snake bitten dog? Anything I should look out for? Anything like that?

Dr. Michael Schaer:
I know this is go going to sound silly, but I say to the residents, look at the patients and only the patients, so help you God. In other words, don’t walk in there. Oh, I know all about this. I’m going to do this, this, this, and this. It’s like driving your car on the road. You’re going to drive according to the speed limit and the safety conditions, and I’m going to assess that patient according to what that patient is telling me. And don’t be presumptuous. Interpret everything that you see with as open mind as you can, and I think that’ll get you out of trouble. And always remember Uncle Mikey’s maxims because they’re always out there to save you.

Dr. Andy Roark:
Thank you, sir. Awesome. Thanks a lot for being here. I really appreciate your time.

Dr. Michael Schaer:
It’s a pleasure indeed. You take care.

Dr. Andy Roark:
And that’s it. That’s the episode. That’s what I got for you guys. I hope you enjoyed it. I hope you got something out of it. Special thanks to Uncle Mikey for coming and sharing his wisdom. Guys, take care of yourselves. Enjoy the rest of your summer. Be well. Bye.

Dr. Tim Evans, a diplomate of the American College of Theriogenologists and of the The American Board of Veterinary Toxicology, joins Dr. Andy Roark to talk toxins! Dr. Evans tells stories from practice as a toxicologist as he walks through the most common nephrotoxins we see in veterinary medicine today. This episode is not to be missed!

This episode is brought to you by Hill’s Pet Nutrition and the Hill’s Veterinary Academy

LINKS

The Hill’s Veterinary Academy is a one site solution for educating the entire veterinary team. On the HVA, you can find FREE RACE CE from leading specialists and experts, patient-centric education beyond nutrition and flexible, on-demand content that fits your schedule. 

Hill’s Veterinary Academy: https://na.hillsvna.com/

To learn more about the nutritional management of pets with kidney disease, check out the Chronic Kidney Disease Inside Scoop video on Hill’s Veterinary Academy. This video shows you how Hill’s new Prescription Diet k/d ActivBiome+Kidney Defense uses the gut-kidney axis to help pets with kidney disease.

Chronic Kidney Disease Inside Scoop video: https://na.hillsvna.com/en_US/resources-2/view/87

ASPCA Pet Poison Control

Pet Poison Helpline

ABOUT OUR GUEST

Dr. Tim Evans is a diplomate of the American College of Theriogenologists and of the The American Board of Veterinary Toxicology. Dr. Evans was the Toxicology Section Head in the Veterinary Medical Diagnostic Laboratory at the University of Missouri for almost twenty years, until November 1, 2022, and he now wears several new hats at the University of Missouri, including Associate Professor in the Department of Biomedical Sciences, MU College of Veterinary Medicine Public Engagement & Continuing Education Coordinator, and MU Extension Specialist in Animal Health & Veterinary Toxicology. Dr. Evans received his DVM from the University of California, Davis in 1982, and he earned both his MS (1996) and PhD (2002) from MIZZOU. He has been described as “intimidatingly enthusiastic,” especially when it comes to teaching veterinary professional students, and he was recognized as the April 2009 Nerd of MIZZOU and Nerd of the Year in 2010. Dr. Evans was also recognized as a William T. Kemper Fellow for Excellence in Teaching in 2013 and was MIZZOU’s 2015-2016 recipient of the Governor’s Award for Teaching Excellence. Dr. Evans also has a superhero alter ego, THE ANTIDOTE, the enemy of ALL things toxic, who periodically makes appearances in the classroom. Tim has been married to his extremely patient wife, Debbie, for 41 years, and they have two adult children, Andreya and William.

EPISODE TRANSCRIPT

Dr. Andy Roark:
Welcome everybody to The Cone of Shame Veterinary Podcast. I am your host, Dr. Andy Roark. Guys, this is a fun, fun episode. I have the amazing Dr. Tim Evans with me. Dr. Tim Evans is a boarded theriogenologist and also a boarded toxicologist. He is a professor at University of Missouri’s College of Veterinary Medicine, and darn, he is fun. I think you guys are going to love this episode. I love getting to meet Tim and my team still talks about getting to work with him. So he is super fun and this is one of those episodes where there’s somebody who, gosh, they know their stuff and they’re just telling stories, and it is awesome.
And so if you learn from stories and examples and anecdotes and you soak that stuff up and it sticks in your brain, I got something great for you today ’cause you’re going to learn some stuff. This is my favorite way to learn. Anyway, this is a wonderful episode. It is brought to you ad-free by Hill’s Pet Nutrition and their Hill’s Veterinary Academy. Guys, if you’ve not checked out the Hill’s Veterinary Academy it is a amazing site for educating the entire veterinary team. Have a look at it, there’s some links down in the show notes you definitely want to check out. Let’s get into this episode.

Kelsey Beth Carpenter:
(singing) This is your show. We’re glad you’re here. We want to help you in your veterinary career. Welcome to The Cone of Shame with Dr. Andy Roark.

Dr. Andy Roark:
Welcome to the podcast. Dr. Tim Evans, thanks for being here.

Dr. Tim Evans:
Well this is great. I dreamed about being on the Cone of Shame.

Dr. Andy Roark:
Nightmares.

Dr. Tim Evans:
Absolutely dreamed about it.

Dr. Andy Roark:
Oh, my gosh, you are too kind. For those who don’t know you, you are a veterinary toxicologist. You are at the University of Missouri’s College of Vet Medicine, you are also their public engagement and continuing education coordinator.

Dr. Tim Evans:
Yeah, that’s a mouthful, isn’t it?

Dr. Andy Roark:
It is. I had to write that one down. I was like, “I’m not going to remember that.” But yeah, it’s great.
You are so much fun. I am super glad to have you here. It’s time for a quick refresher for me, and I realized this last night when I was having a cookout at my house. And I had a bunch of friends that were over and we were doing shish kebabs, and one of the kebabs hit the ground and my goofy dog snatched a big hunk of onion off the end of the kebab before I could get there. And I thought, “Oh, well, that’s not good.” But how bad is it? Let’s think.
And so I thought that you and I could get together and start to talk about some… We should get into toxins, is what I was thinking. So anyway, we’re due for a review on nephrotoxin. So that’s what I wanted to get in today, I was thinking about, let’s think about kidney disease. The A to B to C there is winding and convoluted, but that’s how I got here.

Dr. Tim Evans:
Yeah. Well on the onions, I mean, eventually if you have severe enough of a dosage… And again, a lot of it, in veterinary toxicology, I mean, everything is toxic. Okay? You watch the TV, you listen to the… Everything is toxic. Britney Spears is toxic, Taylor Swift is toxic, something’s toxic.

Dr. Andy Roark:
Something’s toxic.

Dr. Tim Evans:
But everything is toxic.
But I think it all really comes down to the level of exposure. How much is an animal exposed to? So that comes down to how much onion, how big the dog, and is it just a one shot deal? The dog counted to five, got what it was, ate it, probably not a problem. If that’s your daily routine that you have people come every day… I mean, we had some folks years ago, they decided they were going to grill steaks every evening. And they felt bad for their Great Dane. So they went ahead and grilled onions for their Great Dane. Now does that sound like a fair exchange? The dog wants a steak and they’re grilling onions.
So they gave it onions and for approximately a month, six weeks, two months, it got grilled onions every night. And then the dog started acting kind of lethargic. And they brought him in, the dog was anemic. And then incidentally they get this history. And all we’re trying to do when we’re talking about our patients is we’re trying to get a history, we’re trying to get… What’s the examination? We want to come up with, what are the problems? And then we want to figure out, how do we fix things?
Well this dog was anemic and then the story came up with the onions. And luckily onions will destroy red blood cells, as homolysis. That can cause hypoxia, it can also affect the kidneys. A lot of these things that are out there, and again, everything is toxic if there’s enough of it. You can potentially go ahead and get some adverse changes in the case with onions and the red blood cells, possibly in the liver, in the kidneys. But it all comes down to how much.
And again, this was a Great Dane. Usually when I get a phone call and someone says, “Hey, I got a Great Dane, it got into something,” I’m thinking, “Well it’s going to have to get into a whole lot of something to be a problem.” I mean, most of the time when we’re talking to our colleagues, if someone tells me they got a Shih Tzu or a tiny little Chihuahua or something like that and it gets into something, I start listening pretty carefully because the possibility of that being a problem goes much higher. Then when you’ve got a Lab, which goodness, they eat everything, or you’ve got a Great Dane. So…

Dr. Andy Roark:
Yeah. That makes sense to me. It still makes sense, your old nutrition history for the win is trying to tease that out. Do you have questions when you’re looking for toxins, ways that you like to ask questions to pet owners that you feel like get them to tip their cards a little bit? It’s amazing to me how often I’ll say, “Well what does she eat?” And they’re like, “Oh, nothing. Just regular stuff.” And 35 minutes later the onion story will come out and I’m like, “Well why didn’t I get this early on?”

Dr. Tim Evans:
Yeah, and I think that’s one of the things that makes it a bit hard in veterinary medicine sometimes, in that medicine generally have gotten to the point where you got 15 minutes to figure out what’s going on.
We had a situation over at the Veterinary Health Center where an owner of some really… A very good owner had, I believe, Retrievers, running dogs all the time. She brought this dog, the dog was acting kind of depressed. She thought maybe it was a problem with a dewormer that she had used and then they got some blood work. And then the dog, they found something that… It was an older Golden Retriever, they thought possibly there might be a problem like some type of cancer or something like that. You get into a referral center and we’re looking at everything in the world and trying to figure out what’s going on.
And so we got people working on this part of the dog and people working on this part of the dog. And they said, “She still thinks it could be some kind of poisoning, and she said she wanted to know if you’d come over and visit.” And a guy like me at the time, I was in the diagnostic lab, I mean, actually being allowed into the hospital… I mean that’s like, whoa, that’s like being on the Cone of Shame, Andy. That’s like being on the Cone of Shame.
So I got in and I sit with the client, we’re talking about it and she said, “Well the dog was acting kind of drunken and it just…” She thought that it could’ve been this dewormer. And then she’d had a lot of workers working around the house and they’d had a bunch of vehicles and all of this. She said, “Well what kinds of things can cause this kind of behavior?” And so I’m going down the list of things and there’s the ivermectins, the macrocyclic lactones, that class of drug. And then I’m getting in, “Well, and then there’s alcohol. There’s bread dough, yeast decides to rise in the animals so then you get ethanol.”
And then I said, “Well there’s always ethylene glycol. I mean, were there any dripping radiators or anything like that?” And she said, “Well they had a bunch of vehicles there.” She said, “Well how do we figure out if that’s the problem?” I said, “Well you got a complete blood count, you got a blood panel this morning. We went ahead, we got a urinalysis.” So we go ahead and we’ve got some blood work on the animal. We got a CBC, we got a chemistry panel looking at liver, kidney, a variety of different organ systems. And then we get a urinalysis. Okay, we can look at those results when we get them and that can give us some idea if we’re concerned about a possible exposure to ethylene glycol, maybe that could have occurred.
So we go ahead at the end of day, we get the blood work, we’re all thinking this chance of it being ethylene glycol is next to nothing. And all of a sudden what we do, we get the urinalysis and we’ve got calcium oxalate monohydrate crystals, we’ve got an increased anion gap. And this dog, and it was not something on the radar, had gotten into ethylene glycol. Excellent owner, breeder, made sure that everything was just right. But when you get a lot of people and a lot of things happening, who knows? And ethylene glycol is generally pretty sweet and it doesn’t take a lot. This was an older dog. And unfortunately this dog ended up going into renal failure. I mean, yeah, those are the kinds of things.
And so everything is toxic, but again, it depends on the amount. And sometimes it’s the simplest things. Years earlier I’m in the VHC, the second time they let me in it, and then there’s this Great Dane. And this Great Dane is in there, and the Great Dane had had surgery on its spine. They thought it was a wobbler, they were going… I was there for another reason, but they were taking the pictures and pinching it. And this dog all of a sudden goes ahead and he just takes his head, and it just kind of looked like this right at you. He looked like my roommates my first year of that school, on a Saturday morning. It just looked like that.
And I said, “Could this dog have gotten into ethylene glycol?” And the residents looked at me and they said, “Dr. Evans, you always think it’s an intoxication.” I said, “I can’t help myself.” So I was working on my PhD at the time, writing my dissertation. So I was working into the wee hours in my office, and so I’m running on this dissertation. And all of a sudden I get this phone call and it’s from the people over in the ICU and they said, “Dr. Evans, Dr. Evans, this is amazing. We went ahead, we looked at the blood work on the dog. The dog had an increased osmo gap, and just at that point in time he vomited and this fluorescent green fluid just was all over the floor. Dr. Evans, you were right.”
And I said, “Well, yeah.” He said, “Whoa, okay.” So they said, “Well can we test it to see whether it’s… It’s the fluorescent green.” I said, “Yeah, I’ve got a really expensive test for that. We’re going to take that vomit and we’re going to see if it freezes. Okay? And I’ll know pretty quick.” Didn’t freeze. Okay? That’s what it was.
So those kinds of things, I mean, we started out with a Great Dane and onion and now we’re a Great Dane with ethylene glycol. And it’s funny, when you talk about trying to go ahead and get a history you never know when that pearl of information is going to pop up that actually gets you thinking. A dog had surgery, so great, and it was a wobbler, had to be something was going like that. The fact that this dog had probably drank a half gallon of antifreeze seemed to not be in the cards.
So again, there’s a lot of things that people don’t recognize that are around the house, that are in our homes that potentially can be problematic. And again, oftentimes it’s just people’s natural to think that it’s somebody else possibly trying to poison their pet, when its actually just things that are around the home.

Dr. Andy Roark:
Yeah. Stepping back real quick, the frozen vomit test, is that written down somewhere? Can you look that up or is that an actual diagnostic test? Or did you just-

Dr. Tim Evans:
No, it’s a Dr. Evans. It’s antifreeze, does it freeze?

Dr. Andy Roark:
Okay, all right.

Dr. Tim Evans:
So there [inaudible 00:14:40].

Dr. Andy Roark:
My head kind of exploded for a moment. I was like, “I’ve never heard of this test.” And…

Dr. Tim Evans:
I think these cases are good illustration of things that we find around our house that are potentially a problem. Some of them you got to consume a lot of. Okay? For ethylene glycol, a dog has to consume about four to six mils per kilogram. And that’s pure ethylene glycol. So let’s figure, if it’s half ethylene glycol it’s got to be close to 10 to 12 mils per kilogram. Let’s figure you got a 20 pound dog, 10 kilogram, that’s close to 120 ounces. I mean… Yeah, close to 120, not ounces, 120 mils. We’re talking four ounces. Okay, got to do the math there. It’s four ounces, that’s a pretty good amount of ethylene glycol and that’s a 20 pound dock. Go ahead and take a 100 pound dog, you’ve got quite a bit.
And again, it’s the one thing. And students, vet students love math. They love math. So do veterinarians, actually.

Dr. Andy Roark:
So there’s a right answer, yeah.

Dr. Tim Evans:
Yeah. But again, we have to get the calculations. And so we add that all together and then we go ahead. When we talk about intoxications we talk about, how are we going to go ahead and treat it? Well we’re going to remove from the source, we’re going to stabilize, supportive care and then we’re going to try and prevent it. In the case of ethylene glycol what you’re left with most of the time with treating is, we’re going to use ethanol or we’re going to use 4-methylpyrazole. People call it fomepizole.
I had a student who one day in the parking lot said, “Dr. Evans, I want to do emergency medicine and you taught me about 4-methylpyrazole, 4MP, but you never taught me about fomepizole.” I said, “Okay, let’s just… 4-methylpyrazole, fo-me-pi-zole. There you go. Okay?”

Dr. Andy Roark:
“You were just taught about it.”

Dr. Tim Evans:
Yeah. But again, and you could get 4-methylpyrazole or ethanol, Everclear. I mean, I’m in Missouri, you go to your corner liquor store and there’s a variety of protocols you use. But you give the animal IV ethanol, a 30% solution, a bolus dose. Then you keep it on a continuous infusion for a period of time with, if you could get 4-methylpyrazole, fomepizole. You dose a number of multiple doses, but you’re doing that to prevent the animal from making some of the more toxic metabolites of ethylene glycol. Okay?
So that’s how we address that. But you got to get after it quick. And if the dog or the cat is already in kidney problems there’s not a whole lot you can do. That’s the unfortunate part. So that’s that aspect we kind of talked about. How do we work up a case? How do we talk about these things? How do we treat something like ethylene glycol? Let’s go to another common problem that would affect the kidney, let’s talk about grapes and raisins in dogs. Okay?
So for some reason never in my mind did I think, “I got a dog, I’m going to give it a treat. Let’s give it a grape.” I just never quite occurred to me that that was… Well a lot of people like giving grapes and raisins to dogs. I mean…

Dr. Andy Roark:
Oh, I get it. I totally get it. It’s a perfect little treat size. You’re there, you’re eating it. It’s mostly water. You go, “How could this be bad?” And I totally get it. I totally get it.

Dr. Tim Evans:
Yeah. Well see, that’s why you are where you are as the host of the Cone of Shame, and I’m a toxicologist.
So we’ve talked about for probably… I mean, it’s probably been close to 15 years where the animal poison control center brought attention to the fact that they were seeing problems with grapes and raisins. And some animals seem to be particularly sensitive. I mean, some animals, it takes a boatload of grapes, maybe less in the way of raisins. But some dogs, little dogs, you get a box of raisins and they go into renal failure. So that’s an interesting… In that case we’ve got different kinds of intoxications where we have differences in sensitivity of different animals.
And in this case some animals are much more sensitive dogs, it’s a dog thing. In my mind it’s a dog thing. You’ve got grapes and raisins, and particularly raisins, because whatever it is… We didn’t know what the toxin was but now the belief is that tartaric acid or potassium bitartrate are somehow involved in that. We don’t know how, and we don’t have really a way to test for it, but they can… What happens is the dog gets into it, they start vomiting and then they end up with the tubules in the kidney, which play an important role in what the kidney does, basically are damaged. And then we get into renal failure and kidney failure.
And so this is one of these things that I tell people, “Just don’t give grapes and raisins to your dogs.” And I was trying to get my hair cut yesterday ’cause I was coming on the Cone of Shame, and my regular barbershop, they were closing in 10 minutes. And so I went to a new barbershop and the lady there says… And I was dressed, don’t ask me why, but I had an emu shirt on and wearing my tiger striped pants, okay? Wearing my tiger striped pants. It doesn’t leave much to the imagination of where I work.
And she says, “I have a dog, I have a French bulldog.” And I said, “Wow.” And she says, “If you could tell me anything, you said you’re a toxicologist, if you could tell me anything, what should I not do?” I said, “Well, don’t give it grapes, raisins, don’t give it chocolate, don’t give it those kinds of things. It’s a dog, get dog treats for the dog, okay?” So then she asked about grapes and raisins, “Well grapes and raisins, I always think that…” And she said that, she said, “Well they’re so much fun and when they eat them they explode.” And I said, “No, that’s a less than ideal thing to do.”
Now again, how many times do we get phone calls from somebody who says, “Oh my gosh, my Great Dane ate one grape?”

Dr. Andy Roark:
One grape.

Dr. Tim Evans:
Well that’s probably not going to be a problem. But what we do need to recognize is, has that dog ever had that kind of poisoning before? Has that dog had grape and raisin intoxication? If it’s had it before then yes, maybe one grape, particularly multiple raisins, might be an issue.
And I think this brings us back to a lot of things, and you know, dealing with pets and with organ function, I mean, the kidneys, we don’t really know they’re not working until they’re really not working. And so we go ahead and we see an elevation in the blood urea nitrogen or the creatinine, and we go, “Oh my gosh.” But we don’t always…
And a good example of this grape and raisin analogy. You talk about in dogs, I believe it’s a dog thing. Anecdotally some people say, “Well there may be cats.” There’s been reports of cats having kidney problems and they’ve ate one raisin. Okay? Well as you and I both know, cats are basically chronic kidney disease waiting to occur. I mean, I love cats.

Dr. Andy Roark:
Oh yeah, no.

Dr. Tim Evans:
My best friend is a cat, but I’m not giving it… I’m watching out for his renal function. But what happens is a cat eats a raisin and then the cat’s not feeling well, and somebody goes ahead and does the blood work and they see the cat has renal disease. And now it’s got to be because it ate the raisin, not just because it’s a cat.
And that brings us to the point of going ahead, and when we get our patients that come into clinics I always think it’s a great idea to get baseline blood work. Dog’s coming in for a puppy check, or even a dog’s coming in for its annual shots, whatever, getting that blood panel and looking at, are we seeing any type of changes in the red blood cells, white blood cells? Are we seeing anything in the blood chemistry indicative of potential liver disease or kidneys? Something like that. That gives us some baseline information that we can go back and then go ahead and figure out.
So when I’m talking about cats and grapes and raisins, and I don’t think that’s a thing. On the other hand we’ve got cats and true lilies, that’s a thing. And so I think a lot of this is trying to organize those thoughts and put them in. And again, teaching veterinary students, I’m trying to get them to think in terms of a system of how do you look at things and put it together? And in the case of cats and lilies, true lilies… Lily is like Smith of the plant kingdom, okay? Everything’s a lily. But the true lilies, the Lilium genus, the Hemerocallis genus which is your Easter Lily, Asiatic Lily, all of those other lilies, and then your Day Lily, those potentially can be associated with kidney disease in cats. Even the pollen, even the pollen is enough to cause a problem.
We don’t know what the toxin is. We know that if the cat eats even a tiny bit that it’s a potential problem. You go ahead, you take it to the veterinarian, you go ahead, you put the animal on fluids. Usually we put it on IV fluids for about ideally 72 hours, sometimes we can get away with less. But it’s an emergency. I mean, it’s like the Great Dane and one grape, not an emergency. The cat who’s got yellow pollen all over its face from… And it just happens to be Easter or it’s prom, everyone at prom time’s got to have lilies, and then we go from there.
And so those are the kind of things that we take [inaudible 00:27:43].

Dr. Andy Roark:
All right. Dr. Tim Evans, you are amazing. Do you have any favorite resources before we go that you love for people who are like, “I want to brush up on toxicology,” or, “This is really an area of interest for me?” Anything that you like to point people towards?

Dr. Tim Evans:
Well, I would say that I think the poison control websites, particularly the Pet Poison Helpline and the ASPCA Animal Poison Control Center, great websites, phone apps. Certainly you can call for a consultation, but they’ve got lots of free resources that can answer a whole lot of questions. And there’s a number of pretty good textbooks out there that give us some good information. And yeah.
So I love what I do. I hope I met your requirements for maybe coming back to the Cone of Shame again. So…

Dr. Andy Roark:
The stringent requirements for return visit. I think so. I think you’ve far exceeded what I hope for. This has been wonderful. I appreciate the heck out of you. Guys, thanks for tuning in and listening, everybody. Take care of yourselves, be well.
And that’s it, guys. That’s what I got for you. I hope you enjoyed it, I hope you got tons out of this episode. Thanks to Dr. Tim Evans, he is so fun. I so enjoy getting to sit down and talk to him. Thanks to Hill’s Pet Nutrition for making this episode possible.
Guys, if you want to get into the actionable treatment steps coming out of this episode, if you’re like, “Hey, I really want to get into management of these conditions. Hey, I really want to get into the latest in therapeutic intervention for nephrotoxins.” I got you covered. Head over to Hill’s Veterinary Academy and check it out. They’ve got a video called The Inside Scoop, and I linked all this in the show notes. But guys, everything that you need to address these issues to get into treatment and ongoing management of the things we talked about today is right there for you.
So anyway, go and check that out. Links for all this stuff down in the show notes. Gang, take care of yourselves. I’ll talk to you soon.