Veterinary Vertex
Veterinary Vertex is a weekly podcast that takes you behind the scenes of the clinical and research discoveries published in the Journal of the American Veterinary Medical Association (JAVMA) and the American Journal of Veterinary Research (AJVR). Tune in to learn about cutting-edge veterinary research and gain in-depth insights you won’t find anywhere else. Come away with knowledge you can put to use in your own practice – along with a healthy dose of inspiration to remind you what you love about veterinary medicine.
Veterinary Vertex
Blocked Cats, Clear Choices
Hyperkalemia in a blocked cat can feel like a five-alarm fire—until you remember what actually fixes the problem. We sit down with Drs. Stephanie Maciorowski and Elizabeth Rozanski to unpack fresh evidence showing that the simplest path is also the strongest: start IV fluids, give calcium gluconate to stabilize the myocardium, and prioritize rapid unobstruction. The headline finding is liberating for busy ERs and general practices alike—insulin with dextrose, terbutaline, or sodium bicarbonate did not outperform the foundational approach in lowering potassium or improving outcomes.
We walk through what this means at the cage-side level. Potassium often falls quickly once urine is flowing, so the early hours matter most. If a catheter won’t pass, decompressive cystocentesis can reduce pressure and buy time. We compare sedation choices, discuss monitoring strategies, and highlight which lab and ECG changes deserve your attention. The conversation also tackles a bigger theme: replacing ritual with proof. Many of us learned to stack drugs out of habit or anxiety; this study suggests we can streamline, reduce risk, and still deliver excellent survival—especially when teams move decisively to address the cause rather than chasing every downstream sign.
Along the way, we cover client education essentials—how to spot a block early, why immediate care matters, and what prevention looks like after discharge. For clinicians, we sketch out future research that could refine timing, trend analysis, and case stratification, including earlier potassium checkpoints and ionized calcium tracking. If you care about better outcomes, safer protocols, and fewer medication complications, this conversation offers practical, evidence-based steps you can use today.
If this episode helps you rethink your protocol, share it with a colleague, subscribe for more data-driven conversations, and leave a quick review so others can find the show.
JAVMA article: https://doi.org/10.2460/javma.25.04.0258
INTERESTED IN SUBMITTING YOUR MANUSCRIPT TO JAVMA ® OR AJVR ® ?
JAVMA ® : https://avma.org/JAVMAAuthors
AJVR ® : https://avma.org/AJVRAuthors
FOLLOW US:
JAVMA ® :
Facebook: Journal of the American Veterinary Medical Association - JAVMA | Facebook
Instagram: JAVMA (@avma_javma) • Instagram photos and videos
Twitter: JAVMA (@AVMAJAVMA) / Twitter
AJVR ® :
Facebook: American Journal of Veterinary Research - AJVR | Facebook
Instagram: AJVR (@ajvroa) • Instagram photos and videos
Twitter: AJVR (@AJVROA) / Twitter
JAVMA ® and AJVR ® LinkedIn: https://linkedin.com/company/avma-journals
From the makers of FET recommended Green East Dental Treats comes an easy way to support your dog's wellness. Green East Smart Essentials Dry Food delivers complete balanced nutrition with science-backed recipes. Green East Supplements, developed by a team of PhD animal nutritionists, offers options to help support healthy joints, digestion, and more. Whether it's meal time or mobility support, Green East helps you care for your dog from the inside out. Learn more at greenies.com.
SPEAKER_01:This is Veterinary Vertex, a podcast of the AVMA Journals. In this episode, we chat about how pharmacological therapy for hyperkelemia and feline urethral obstructions has no additional benefit over intravenous fluid and calcium gluconate therapy and prompt on obstruction with our guests, Stephanie Makarowski and Elizabeth Rosansky.
SPEAKER_04:Welcome, listeners. I'm Lisa Fortier, editor-in-chief for JAVMA. I'm joined today by Associate Editor Sarah Wright. Today we have Stephanie and Elizabeth joining us, and thank you guys so much for taking time out of your busy schedule to be with us here today.
SPEAKER_02:Excellent. We're happy to be here. Thanks for having us.
SPEAKER_01:All right, let's dive right in. So today we're talking about an always timely topic: blocked cats. So, Liz, your JAVMA article compares the effect of IB fluids and calcium gluconate alone or with insulin dextrose tributylene or sodium bicarbonate on hyperkelemia and male cats presenting with urinary obstruction. Please share with our listeners the background on this article.
SPEAKER_03:Sure. So in the emergency room, as everybody's familiar, we see a lot of block cats. And the sicker block cats tend to come with very high potassium levels. And there's always been kind of internal debate over what's the best treatment for that. And we noticed that a lot of people at some point learn to run for the insulin and dextrose. That's probably the most common thing. And then you hear about cats that got insulin that then people forget to give them dextrose and then they're having hypoglycemic problems, or they don't remember how much glucose to give or how much insulin to give. And so when we were looking at that, that was kind of our driving question was does it really help to do that? The kidneys are pretty smart. You know, they're not the best organ, but they're a good organ. And they're really good at figuring out stuff. So our thought was, gosh, if we can get them unobstructed, I bet they're going to take care of it pretty quickly on their own. And if we could show that, um, that would be something that would be really interesting to help people in practice and to help people not worry about the insulin and how much um dextrose they're supposed to get. But at the same time, we um because we do a lot of dogs, we also see the dogs that bite on the albuterol inhaler and they drop their potassium really, really low. And then when you look into that a little bit more in human medicine, there's some work using the beta-2 agonists, so like turbutylene and albuterol for lowering the potassium. And I know in in JAVMA earlier this year, another article came out talking about um albuterol in cats. Um, we have terbutalin for our asthmatic cats. I wonder if this would be an easier, safer, effective choice as well, uh, mostly because you don't have to follow it up with anything. And then we wanted to add bicarbonate because that in some of the older textbooks gets a lot of press says, oh, you can do this by changing the pH. This will help as well. And so as we're talking about that, we're like, well, let's try to set up something where we try to take these head to head to see if we can show if one is really better or is really just on blocking them and giving them fluids and calcium. Is that going to do the trick? So that's how we got to it.
SPEAKER_01:Yeah, super interesting. I think it's good to just remember all the different options. And now we have evidence too, right? Behind different recommendations. So thank you for that. So, Stephanie, what are the important take-home messages from this Japan article?
SPEAKER_02:I think there's two really big take-home messages. The first one is that we always kind of thought that they would have a worse prognosis, these cats, when they came in with this higher potassium. But the studies show that all of our cats survived despite having some really high potassiums here. So even if you recognize that in lab, we're still giving these guys a shot with treatment is very reasonable. The other big takeaway is like we mentioned, all these treatments seem to have similar outcomes where they all did well. And statistically, we didn't see any significant difference between the decrease in potassium over time. So any of these treatments could be helpful. But again, the big priority is getting them unblocked and giving them IV fluids.
SPEAKER_04:Yeah, very important point. You know, we see this in a lot of human and veterinary medicine. Add another drug, add another drug, add another drug. And just because you can doesn't mean you should. And then it just adds up, right? And there every time you add a drug, there's another side effect, and then you have to give another drug for a side effect. So I really applaud this effort. Liz, what sparked your interest in this not the best organ? I'd like to know what you think that is the best organ since you don't think so highly of the kidney.
SPEAKER_03:I I do like the kidney, it's it's absolutely an important one. But we spend, I spend a lot of time preaching the major body system, so the heart, brain, and lungs. And so those are the organs that are going to kill you. So when I think as the heart, the brain of the lungs, I would say they're equally important. The kidneys you can go a little while without working, but you you honestly want good kidneys. Um I am always impressed at how well the kidneys sort out things. And when we have in other debates in emergency medicine, do you give lactated ringers or plasma light or sodium chloride? Um, really, all the investigations have shown with normal kidneys, give something and they'll be okay. Um, so I do like the kidney from that standpoint. Um, it's just not a the best organ out there.
SPEAKER_04:Well, in this specific topic of comparing all these medications head-to-head, uh, what what what what was the impetus for for this study? What sparked your interest in this topic?
SPEAKER_03:Oh, what sparked our interest is again, uh years of block cats that come in with hyperkalemia. And one of our co-authors, um, uh we call him VK because we can't pronounce his last name either. Steph might do better with it.
SPEAKER_02:Um, do you want to give it a try? Oh gosh, I can't. I still got my VK.
SPEAKER_03:We call him VK. Um, and he is a bit of a curmudgeon. Um, and he is one of our co-investigators. He was a resident here a couple of years ago, and he was constantly fighting with us for what the right answer was and where was the evidence. So, really um, really intellectual um as well as combative, but in a good way. Um, and it was really his idea as far as can we try to look at these things because we are having a lot of um when we think about fun things in emergency medicine, there's so much that we still don't really know. It's kind of fun to have good debates over what do you think you should do? What would we do? Um, and then a lot of the block cats, because they're so common, people learned something in veterinary school or in their first year or two out, and they never really questioned it. Um, and so there's been, you know, how do we um like flushing the cat's bladder out? Is that really helpful? Is there other things that that we kind of do out of tradition rather than evidence? And so VK was great for let's look at some evidence. And we had had a run of really badly hyperkalemic cats. Um, and we're always upset where different places people say things like, oh, these guys are never going to survive, like you should just euthanize them. Um, and so we were really like, I think they do pretty well. Let's see what we can do with that. Um, and then we spent some time trying to make sure they were as matched as possible. Um, because obviously different people use different drugs or different fluids. So we it took a little while to make sure we didn't miss a cat, um, as far as doing something different. But yeah, that's the really interesting part about where's the evidence.
SPEAKER_04:Yeah, I'm a large animal surgeon. We have the same thing in block goats. You know, they're they're frustrating, they can be expensive, and then they recur. And yeah.
SPEAKER_03:Uh, we're doing a project with our um large animal folks looking at block goats as well, um, just as kind of for that same thing that you're talking about, kind of that overlap between species and how we can work together.
SPEAKER_04:Yeah. Yep. All part of probably what we're doing is feeding them it was a Western diet. I doubt all those goats out in nature get blocked. There wouldn't be any goats. Every time, uh, Liz, that we do a study, and you know, this is this is a fabulous study with all the different groups, um, but we're always surprised by something. And I think one of the surprises I've heard is that the animals do better regardless, or they do well regardless of a high potassium. What are some what are some other surprising findings?
SPEAKER_03:Um, what did you want to? I think to me, other surprising findings was um that it they potassium falls fairly quickly. Um, and I think that that's something where um from a clinical standpoint, um, when you if you recheck laboratory work 24 hours later and it's not better, you really should be anxious over that. And we don't really have a lot of good data over like what does creatinine or potassium do every half an hour or things like that. So I think we need a little more looking at that. So I was pretty impressed within a couple of hours that the cats were back to what we would consider a cardiovascularly safe range. Um, the other thing that's probably important to note is and we did on we gave the cats a food bowl is pretty quickly, and we also unblocked them pretty quickly. Um, and I think sometimes people talk about trying to make them more stable. Um, and I think to me it's really important that the thing that's gonna make them more stable is unblocking them. And so, you know, in our hospital, certainly a not sick block cat might wait 15, 20 minutes to get unblocked, but these guys are, I think, a bit pretty big all hands on deck because they're gonna be fixable. Um, this is a disease we can we can improve the outcome, they're gonna do well with that. Um, so that's that to me is something I'd like us to kind of focus on as a profession is these guys come in, get them some fluids, get them unblocked. Um, so I don't think yeah, I don't know what stuck would add to that.
SPEAKER_02:Yeah, and I would say that along with the concern for mortality going into these cases, all these cats did really well. But I think the big thing was getting them at least some fluids and the calcium glutinate, and then just getting them unblocked as soon as possible is again just the most important thing to get these guys on the road to recovery.
SPEAKER_04:I think the exact same for the goats. We'd have these debates from surgeon anesthesia about we need to stabilize them cardiovascular for surgery. We can anesthetize them with that calcium. And I was like, Well, what do you want me to do here? Exactly.
SPEAKER_03:You have something we can fix. So we need to work on that.
SPEAKER_01:Yeah, I do feel like sometimes we get so caught up with uh trying to treat the clinical signs that we forget the underlying root cause. And sometimes if you address that root cause head on, then you can fix everything else, it'll resolve. So, Stephanie, what are the next steps for research in this topic?
SPEAKER_02:So I think a little bit of what Liz alluded to was seeing exactly how quickly this potassium drops. We only looked at the one time point four hours after. If we were able to check that more often, I think that would be really interesting to look at as well. Um, another thing to consider would be looking at other lab work changes. We had looked into the creatinine, but also maybe looking at their ionized calcium as well would be really interesting in these cases. And maybe even looking at ECG changes in these cases as well. We all know kind of the the classic ECG changes, but actually seeing clinically how that correlates with the patients coming into the ER would be really cool.
SPEAKER_01:Yeah, I definitely look forward to that. Sounds really interesting. Well, we hope to see some of your manuscripts then across Stardust. And Stephanie, do you see a role for AI in this area of research?
SPEAKER_02:That's a great question. I feel like that's the hot topic nowadays, as so whether AI could come in. And I think, you know, maybe it could come in to help go through different treatment options. But I think at the end of the day, we have so much knowledge and experience that I don't think AI will ever really replace that in our veterinary expertise.
SPEAKER_04:Elizabeth, you talked earlier about a uh resident that you had that was maybe a bit challenging. I think those folks are fascinating. Oftentimes it was students from me that would say, Do we know that for sure? Is there evidence for that? And so sometimes that sparked some of my best studies. So, how did your training or even the train you being a mentor, how did that prepare you to design this complicated experiment and then write this article?
SPEAKER_03:Oh, yeah, that's a great question. And so to be clear, we love VK, but he is a curmudgeon. Um, I think that what you're looking for in you know, in any veterinarian or veterinary technician is intellectual curiosity. And so certainly there's times to uh like for as a from a surgical standpoint, we always tell people you should never ask, is it supposed to bleed that much? Um, like that's a bad question. Um, but asking questions about things that you learned, um, I think one of the interesting debates that's really hot right now is when do you span neuter dogs? Like, how do we answer those questions? How do you answer the question? We do a lot with GDV as well. And when you look at the history of um dogs with bloat or GDV, it was, you know, we figured out finally, you know, 50 years ago and give them fluids and maybe we could take them to surgery. And you know, so each little widget gives us more information. Um, so to me, um, we at Tufts, we end as well as a lot of the other veterinary schools, of course, have a pretty active student summer research project. Um, and I love seeing what they come up with as their ideas. Um, and so from uh from an ER standpoint, there's really a million unanswered questions. Um and I think it just keep picking away at each little question is really fun. So we love the people who come up with what do you think we should do? We had one student this summer who was looking at um do the dogs sleep more if the lights are off in the ICU? Um, and so um, and this is perhaps one of our best statistical findings is that using our light meter, it's significantly darker when the lights are off. Um so that's what she found as her project. Um, but the rest of it, she found that um dogs didn't really care if the lights were on or off or how loud it was. They were happy to sleep no matter what. And so that was really um those type of questions that seem kind of common sense really aren't sometimes common sense. And so I think as a profession, as we keep kind of picking those off, those are great. And we love the students and house officers who come in with, hey, I'd like to question what I think we should be doing and try to answer that a little bit better. So those are fun questions.
SPEAKER_01:So now this next set of questions is going to be really important for our listeners. The first one's going to revolve around the veterinarian's perspective. So, Elizabeth, what is one piece of information the veterinarian should know about resolution of hyperkalemia in cats presenting with urinary obstruction?
SPEAKER_03:To me, the most important thing is give fluids, give calcium, and unblock them. That is the and do it quickly. I think that we um stratified our anesthesia sedation protocol, but using drugs that you're comfortable with and using uh conservative doses of them and unblocking them quickly. If you can't get them unblocked, luckily, um as you remember, potassium kind of lowers muscle tone. So most hyperkelemate cats are actually easier to unblock than some of the other cats. But if you can't get them unblocked, you can also do a decompressive cystocyntesis where you actually get rid of all the urine, not just a five mil sample, but like hook up a uh inch and a half um 22 gauge needle and take off 100 or 250 mils. And if you can't get them unblocked, that will help as well. So to me, the biggest take-home is these cats are absolutely fixable, but you need to act quickly. Um, and I think we need to make sure you talk to the owners about what to watch for and making sure that they're aware that this could happen with their cat.
SPEAKER_01:My sister-in-law just adopted a male cat and she's already asking me. She's like, So I heard they need to drink a lot of water. I'm like, all right, we have some, we have some things to discuss here. So, Stephanie, on the other side of this relationship, what's one thing clients should know about this topic?
SPEAKER_02:I think the first and most important thing is knowing that this is a problem. If your male cat is going in and out of the litter box a lot, you're not seeing regular urinations or some stressful event, like keeping an eye on that and getting them into the vet as soon as possible. Like I would much rather have the cat that the owner is concerned they're blocked and they're not actually blocked than the one that's coming in, you know, peri-arrest really sick. So I think the biggest niche is client education about this problem. Because then from there, you know, discussing we can treat this, the different environmental modifications, things we can do from there are all education points that we can work with on the clients, but they first need to know that this is a problem that they should just be aware of to try to help out their little kitties at home.
SPEAKER_04:Very good point. Thank you again, you guys. Uh, such a timely and always a timely and important topic for veterinary medicine. Um, as you wind out, we'd like to ask a little more of a fun question. So, Liz, uh, we'd like to know what was the first concert you attended?
SPEAKER_03:Uh, first concert was Billy Joel at the Rosemont um outside of Chicago when I was in high school. That was very cool. A good concert.
SPEAKER_04:Yeah, he he was still very, he is still very good. And Stephanie, uh, you're an ER doc. I'm not sure what the answer to view of this. We Sarah and I have a hypothesis, and we're gonna do a little study on this question. When you complete a puzzle, Stephanie, do you begin with the middle or the exterior? Or do you do a pattern? How do you approach a puzzle? You have to always do the edges first. I feel like that's chaos or in the middle. So what's what's panning out is anybody who has like a uh surgeon mentality does the exterior, and medicine folks usually do the interior. Oh, really? So you're you're as an ER doc, you're kind of a hybrid.
SPEAKER_03:Yeah, absolutely. Yeah, I I would I can imagine not starting with the edges.
SPEAKER_02:Right. I totally more surgery than medicine, too, anyway. So that seems to fit. Right.
SPEAKER_01:It's awesome. Yeah, we're gathering a lot of data for this, Lisa. We might have to do something with it at some point. Evidence. Yeah, exactly. Exactly. Well, thank you so much, Stephanie and Liz. We appreciate you being here today and also for sharing your work with Javma. Of course. We're very happy to be here. Thank you guys so much for having us. And to our listeners, you can read Stephanie and Elizabeth's article in Javma. I'm Sarah Wright with Lisa Fortier. Be on the lookout for next week's episode, and don't forget to leave us a rating and review on up a podcast or whatever platform you listen to.
