Clostridial myositis, also known as gas gangrene, malignant edema, or clostridial myonecrosis, is an infection of skeletal muscle by any of several 

species. Pathogenic bacteria within the genus 

are anaerobic, gram-positive rods that can produce spores that are resistant to various environmental and chemical factors.

The key component for clostridial myositis to occur is the creation of a local anaerobic environment within the skeletal muscle, which can occur with tissue injury, along with the presence of spores or bacteria. There is still debate whether these spores may be introduced at the time of injury or reside within the skeletal muscle prior to injury, and both sources may be valid.

 Clostridial myositis is reported to occur most frequently secondary to intramuscular injection, particularly of flunixin meglumine; however, it can also occur because of wound contamination, perivascular injection, castration, foaling injuries, or omphalophlebitis.

 Rare cases have no history of open injury, and in these cases, previous seeding of the muscle with spores followed by blunt trauma is suspected.

Once the clostridial spores or bacteria have the correct environment for spore germination and bacterial proliferation, toxin production results in severe tissue necrosis, along with systemic toxemia and bacteremia. Malignant edema is when cellulitis is present without myositis, but it may progress to involve the skeletal musculature.

Clinical signs of clostridial myositis are typically seen within 6 to 72 hours of injury or injection.

 Systemic toxemia may develop very quickly after the onset of clinical signs, and animals may be found dead.

 Initial clinical signs include fever, severe lethargy, tachycardia, reluctance to move, and anorexia. The affected site becomes swollen and painful and develops crepitus and subcutaneous edema.

 Horses may become recumbent because of systemic toxemia and severe pain.

A presumptive diagnosis of clostridial myositis is often made based on clinical signs and history. Aspiration of the swollen, edematous areas reveals serosanguinous, malodorous fluid with or without gas. Gram stain of the aspirated fluid often reveals gram-positive, spore-forming rods.

 Exudate and/or affected muscle tissue can be submitted for fluorescent antibody testing, immunohistochemistry, anaerobic culture, and/ or polymerase chain reaction for confirmation and species distinction, which may affect prognosis.

 Clinicopathologic abnormalities are nonspecific and consistent with a septic process, and elevated muscle enzymes may be noted but often do not correlate with the degree of myonecrosis.

 Ultrasound and/or radiographs of the area will show areas of subcutaneous edema and gas under the skin (

Images courtesy of Erica Secor, DVM, MS, DACVS-LA

Rapid diagnosis and aggressive treatment are pivotal for the survival of horses with clostridial myositis and, even with appropriate therapy, may be unsuccessful. Surgical fenestration of the skin and fascia, along with debridement of infected muscle tissue, appears crucial to a successful outcome, both through the removal of bacteria and disruption of the anaerobic environment, which lead to bacterial proliferation and toxin production (

Figure 2A, Figure 2B, Figure 2C, Figure 2D, Figure 2E and Figure 2F

Typically, the skin overlying these areas will necrose and slough, resulting in large wounds requiring long-term therapy. Wound therapy is crucial following fasciotomy and should include continued debridement of infected tissue, hydrotherapy, topical wound care, and additional fasciotomy if needed.

Antimicrobial therapy includes high-dose potassium penicillin (44,000 IU/kg intravenously every 6-8 hours) with or without the addition of metronidazole.

 Susceptibility suggests that tetracyclines and chloramphenicol should be effective and may be considered for oral medication options following the discontinuation of intravenous antimicrobials.

 Antimicrobial medications should be continued for a minimum of 7 days following infection resolution.

Hyperbaric oxygen therapy is often used in humans with gas gangrene and may improve survival when used in conjunction with surgical debridement; however, this is not common equipment in most equine hospital facilities.

 Additional supportive measures may include intravenous fluid therapy, management of anorexia through intravenous or oral routes, and pain management. Additional complications can arise because the primary disease process includes hemolytic anemia

Complications secondary to systemic toxemia may include disseminated intravascular coagulation, multiorgan failure, and laminitis. Airway management by tracheostomy may be necessary in cases where the neck or head is involved because of severe swelling and edema.

Prognosis is guarded for cases of clostridial myositis, with reported survival rates of 31% to 73%.

 Rapid intervention, including fasciotomy, appears key in improving survival rates, with a nearly 40% improvement in survival in horses undergoing fasciotomy in the first 24 hours of hospitalization compared with those with delayed surgical intervention.

infections showing the greatest survival, whereas those with 

or mixed infections show lower survival rates.

 It is important to remember that therapy must be initiated before identifying 

Educating owners on the risks of intramuscular injections, particularly of flunixin meglumine, may help reduce the chance of clostridial myositis. These cases are best managed in a hospital setting, and successful treatment requires the owner’s dedication in time and finances. Although this disease is a rare outcome of skeletal muscle trauma, early recognition and therapy are essential for a successful outcome and, even then, can be difficult to attain.

MacLeay J. Diseases of the musculoskeletal system. In: Reed SM, Bayly WM, Sellon DC. 

Peek SF, Semrad SD, Perkins GA. Clostridial myonecrosis in horses (37 cases 1985-2000). 

. 2003;35(1):86-92. doi:10.2746/042516403775467513

Ortega J, Daft B, Assis RA, et al. Infection of internal umbilical remnant in foals by Clostridium sordellii. 

. 2007;44(3):269-275. doi:10.1354/vp.44-3-269

Uzal FA, Navarro MA, Asin J, Henderson EE. Clostridial diseases of horses: a review. 

. 2022;10(2):318. doi:10.3390/vaccines10020318

Wang C, Schwaitzberg S, Berliner E, Zarin DA, Lau J. Hyperbaric oxygen for treating wounds: a systematic review of the literature. 

. 2003;138(3):272-280. doi:10.1001/ archsurg.138.3.272

Jeanes LV, Magdesian KG, Madigan JE, Meagher D. Clostridial myonecrosis in horses. Comp Cont 

. 2001;23:577-587. http://assets.prod.vetlearn.com.s3.amazonaws.com/mmah/f2/68cc5be7ac420399a2bfe1244bbfe4/ filePV_23_06_577.pdf

Articles

This skeletal muscle infection is best managed in a hospital

Clostridial myositis in horses

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, discusses diagnostic techniques for dermatophytes

Diagnostic tests for identifying dermatophytes

, Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, offers an overview of the various diagnostic tests available for dermatophytosis—a common fungal infection in cats and dogs. In the video, Santoro discusses some pros and cons of each test, and explains what the best diagnostic technique is.

Below is a partial transcript, lightly edited for clarity:

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM: 

One of the common fungal infections is dermatophytosis, and with dermatophytes, there are different type of tests that we can do. The simplest test is called Wood lamp, which is a very sensitive test but not very specific, followed by hair plucking and trichography.

So trichography essentially implies that the veterinarian will take [a] hair sample, look at the microscope, and look for alterations of the hair shaft. This test is very specific, but contrary of the wood lamp, it’s not really sensitive because it depends [on whether] we collect the affected hair or not.

Then there is a dermoscopy, which is a new technique, relatively new, in which we use a magnified lens, essentially, to magnify the visualization of the skin and you can see specific alterations of the hair associated with dermatophytosis.

And again, as I said earlier, the best diagnostic methodology is a fungal culture. So a fungal culture [involves] the collection of hair, specifically the periphery of the lesion, and putting this hair or scales—or whatever material we have—in a culture medium and submitting it to the microbiology laboratory. This test is the best in terms of specificity and sensitivity, but also requires up to 3 weeks to kind of specifically isolate the organism.

Once the organism has grown and is present in the culture, the culture has to be followed by a microscopic identification of the organism. So the microbiologist will specifically look at what type of morphology the organism has, to identify the genus of the species of the fungus.

Domenico Santoro, DVM, MS, DrSc, PhD, DACVD, DECVD, DACVM, discusses diagnostic techniques for dermatophytosis

Shannon Bass, DVM, president of the North Carolina Veterinary Medical Association,and host Adam Christman, DVM, MBA,  to discuss the NCVMA's role in helping those impacted by disasters.

The Vet Blast Podcast presented by dvm360: Are you prepared for a disaster?

On this week's episode of The Vet Blast Podcast presented by dvm360, Adam Christman, DVM, MBA, welcomed Shannon Bass, DVM, president of the North Carolina Veterinary Medical Association to discuss preparedness and ways to help if you are in or near an area that was impacted by some type of disaster. Throughout the episode, Bass shared with Christman why professionals should not just self-deploy, where to access grants, and how much NCVMA has been able to give back to its veterinary community. 

The communities like to get involved too. So not just, I'm assuming, not just the veterinary professionals too, but pet owners and alike, they really want to get involved. So it sounds like it's a collaborative approach to disaster preparedness.

It really is, and we saw so many examples of a shelter might say, I need cat litter. And so pretty quickly, what we saw within a few days, they'd get cat litter, but then someone would find that social media post a week later and start to propagate it again. And then the shelter would get the second and third and fourth wave of cat litter that they didn't meet at that time, and they had no place to store it at that time.

So it was really tricky when you saw kind of this glut of supplies. And then on the non veterinary side, when I was there, a few times, you would drive by churches that had just tables of soaking wet clothes in their parking lot, because so many random clothes had been donated with no real destination that they were just going to get thrown in the trash.

It's unbelievable. And I know the AVMA has some resources through their website as well, right?

They have some great resources. And the AVMF, the American Veterinary Medical Foundation, they donated to the NCVMA. They were great partners. They have wonderful grants as well. And so any AVMA member, and I do think they even have a set of grants for non members. And so the AVMA is has been a really great partner for us. We were able to establish 2 different grants that were new just for this disaster, one [was] veterinary community grants, and those were $300 grants that were available to any veterinary staff member. All they had to do was prove to us that they were employed at a veterinary hospital on the day of the storm. They didn't have to have receipts. It didn't have to be for any specific expense. It was a community grant for those individuals, and that has felt really good. It's not a ton of money, but it's something to to help folks in that area

Podcasts

NCVMA president Shannon Bass, DVM, shares how veterinary teams can help and be more prepared for a natural disaster

Are you prepared for a disaster?

Gianluca Bini, DVM, MRCVS, DACVAA, describes how sedation compares to general anesthesia, including risks and benefits.

Insights on sedation vs general anesthesia

Gianluca Bini, DVM, MRCVS, DACVAA, owner and founder of the Safe Pet Anesthesia tele-consulting and training company and assistant professor of anesthesiology and pain management at Oklahoma State University, shared his expertise with veterinary professionals at the 2025 Fetch dvm360 Conference in Charlotte, North Carolina. During the event, he presented multiple continuing education (CE) sessions on anesthesia and pain management.

, Bini provided additional insights about his CE session. In this segment of the interview, he describes how sedation compares to general anesthesia, including risks and benefits.

The following is a transcript of the video:

: The benefit of sedation is definitely timing, right? We just give an injection. The patient gets sedated. We do what we need to do, and then can either reverse them or, usually, the synaptic drugs don't last that long. So…they can wake up. The risk of general anesthesia, of course, is always that when a patient is anesthetized, that they lose a lot of their physiologic functions, or like they usually lose their swallowing reflex so they can’t protect their airways. They hypoventilate, so they start breathing less frequently and sometimes with smaller breaths.

Sedation, though…although sometimes it seems very benign, in reality, sedation can be as dangerous as general anesthesia, right? So if your patient gets too sedated, your patient is basically almost anesthetized. So the fine line between sedation and anesthesia, for me, from an anesthesiology standpoint, comes into ‘is my patient able to swallow?’ And if it is, then, I carry on with my procedure. But if, if my patient loses the ability to protect its airways, then I need to intubate it and convert to general anesthesia. So there are pros and cons to both. Sedation seems like the quick and easy answer sometimes, but it could be more dangerous than you think.

Videos

Gianluca Bini, DVM, MRCVS, DACVAA, describes how sedation compares to general anesthesia, including risks and benefits, in a dvm360 interview.

Journal of the American Veterinary Medical Association 

), found that inhaled albuterol rapidly decreased blood potassium concentrations in cats. Study results offer a potential treatment option for cats with hyperkalemia undergoing surgery or other medical procedures.

In felines, a urinary tract obstruction is the most common cause of hyperkalemia. A ruptured urinary bladder can also lead to high potassium levels in these animals.

 Moreover, patients of any species with moderate to severe hyperkalemia can exhibit generalized muscle weakness, depression, and cardiac conduction disturbances that can result in life-threatening cardiac arrhythmias.

“Urinary tract disease is relatively common in cats, and decreased renal excretion of potassium in these conditions is the most common cause of hyperkalemia in cats,” the study's authors wrote.

In humans, inhaled albuterol is supported as a first-line therapy for acutely managing hyperkalemia, with the treatment lowering potassium concentrations within 15 to 30 minutes of administration. Effects of inhaled albuterol in humans can last up to 180 minutes.

-agonist that stimulates an intracellular redistribution of potassium through induction of endogenous insulin secretion and activation of membrane-bound Na/K-ATPase pumps in skeletal muscle and liver cells independent of insulin,” the study's authors wrote.

For the study, 20 healthy, spayed/neutered cats received albuterol sulfate at doses of either 90 µg or 360 µg through a mask that was placed over their muzzles. Fifteen were domestic shorthair, 3 were domestic longhair, 1 was a domestic medium hair, and 1 was a Sphynx. Ages of the cats ranged from 1.1

years to 7 years and the median weight was 5 kg.

Blood samples and heart rate from the participants were taken at baseline and at 10 time points following administration of albuterol sulfate, with the final sample taken 360 minutes after the tenth inhalation. Blood potassium and glucose concentrations were measured using a blood gas analyzer, while plasma insulin levels were assessed through radioimmunoassay.

Cats enrolled in the study did not have a prior or newly documented history of cardiac abnormality. Felines who had been administered any medications that may alter blood potassium—such as insulin, sodium-glucose cotransporter-2 inhibitors, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, potassium gluconate, and potassium citrate—were also not eligible for enrollment.

The results showed that inhaled albuterol rapidly decreased blood potassium levels in under 3 minutes, with peak effects happening at 30 minutes after administration and lasting for at least 180 minutes.

 The average maximum decrease in blood potassium concentration occurred in the cats who received the lower dose (90 µg) of albuterol, with the decrease being 0.52 mmol/L.

Additionally, plasma insulin levels increased rapidly after the administration of inhaled albuterol, peaking at 30 minutes and decreasing below baseline by 360 minutes. Time significantly impacted these levels but albuterol dose and the interaction of albuterol dose and time did not impact plasma insulin levels. Both low- and high-dose albuterol cohorts saw significant increases in plasma insulin compared to baseline, but there were no significant differences between the 2 doses.

Additionally, blood glucose levels rose after inhaling albuterol, peaking at 60 minutes for the low-dose group and at 120 minutes for the high-dose group, with both returning to levels below baseline by 360 minutes.

Conducted by researchers at Midwestern University College of Veterinary Medicine in Glendale, Arizona, and Michigan State University in East Lansing, the study’s findings suggest a more affordable and easily accessible treatment option for lowering potassium levels before surgery or other procedures, offering an alternative to other existing methods, according to the AVMA.

Study identifies possible treatment for cats with elevated potassium levels due to urinary obstructions. News release. American Veterinary Medical Association. March 27, 2025. Accessed April 2, 2025. 

https://www.avma.org/news/study-identifies-possible-treatment-cats-elevated-potassium-levels-due-urinary-obstructions?utm_source=delivra&utm_medium=email&utm_campaign=todays-headlines-news

Constable PD. Disorders of potassium metabolism in cats. Merck Veterinary Manual. September 2024. Accessed April 2, 2025. https://www.merckvetmanual.com/cat-owners/metabolic-disorders-of-cats/disorders-of-potassium-metabolism-in-cats

Jaffey JA, Cunha A da, Kushiro-Banker T, et al. Inhaled albuterol rapidly decreases whole blood potassium and increases plasma insulin concentrations, with peak effects 30 minutes after administration in cats. 

Journal of the American Veterinary Medical Association

. Published online March 26, 2025:1-8. doi:10.2460/javma.25.01.0054

A recent study explored the effect of inhaled albuterol sulfate in reducing blood potassium levels in felines, which offers a potential treatment option for urinary obstruction-related hyperkalemia

Inhaled albuterol offers more accessible treatment option for elevated potassium levels in cats

 scrapes the surface of the news you need to know, and the American Veterinary Medical Association’s latest economic report is packed with insights worth paying attention to.

Let’s look at the data from the previous year and break down what some of these trends mean for your practice.

Student debt is growing – corporate hiring power is, too

After a brief decline, student debt was back on the rise last year, with more new graduates carrying over $300,000 in DVM loans. That means corporate groups, with their ability to offer hefty sign-on bonuses, may regain the upper hand in hiring.

However, private practices aren’t out of the running—they just need to play to their strengths. While money matters, multiple studies show that workplace culture is just as important to job seekers. So, how can you stand out?

Define and market your employer value proposition. What makes your practice a great place to work? If you don’t know, start figuring it out—because nearly half of practices don’t have a mission, vision or value statement, and 83.5% lack an employee wellness plan.

 Fix that, and you’ll already be ahead of the curve.

Relief veterinarians are on the rise—with one concerning trend

 that 45% of veterinarians were either planning to switch to relief work or considering it.

 Now, 2 years later, we’re seeing that movement materialize – the percentage of relief vets in private practice has increased from 6% in 2023 to 9.1% in 2024.

What does this mean for you? It’s been said before, but it bears repeating, retention is key. Full-time veterinarians aren’t leaving just for the flexibility of relief work—they’re often driven away by workplace factors like administration, culture, and leadership.

 If you want to keep your team intact, make sure you’re not giving them a reason to look elsewhere.

At the same time, there’s a growing concern: relief veterinarians are the only group whose burnout has increased since the pandemic. They are also the least satisfied with the profession.

 What’s fueling the stress and dissatisfaction? These are critical questions worth investigating—especially for practices that rely on relief vets to fill staffing gaps. As the workforce shifts, the conversation around retention will likely need to shift, too.

Tech gaps, telehealth declines, and the push for efficiency

The report repeatedly emphasizes one critical takeaway: veterinary practices need to prioritize efficiency and make better use of technology. More clinics are adopting digital tools, but there’s still a significant gap. Shockingly, 23.5% of practices still don’t use a practice management system, leaving them without a central hub to manage appointments, records, and client communication. That’s not just an inconvenience—it’s a competitive disadvantage.

There’s also been a sharp decline in telehealth from 38% in 2023 to 29.2% in 2024, but online appointment scheduling is growing.

 Meanwhile, software innovations are exploding—just look at the new tools showcased at VMX and WVC 2025. Artificial intelligence scribes, inventory automation, virtual assistants—it’s all there to save time and money. If you’re not using these tools yet, why not? Most have free trials, so there’s no excuse not to explore what’s out there.

New veterinary practices are opening at a steady clip: total numbers grew from 32,634 in 2021 to 34,000 in 2022, with an 18.5% growth rate since 2009.

 Larger hospitals (20+ employees) are becoming more common, while sole proprietorships are shrinking. This likely points to more corporate ownership but could also mean more independent vets are incorporating for legal or tax benefits. Either way, the trend points to a move away from small, solo-doctor models toward larger, more structured veterinary businesses.

Clinic hours are stretching longer, too. In 2024, the average practice was open 10 hours on weekdays, compared to 9 hours in 2023.

 Extended hours and bigger teams suggest the industry is adapting to meet rising pet care needs – but here’s the catch: the number of available appointment slots hasn’t budged. A full-time veterinarian in companion and mixed animal practice is still averaging 13 to 14 appointment slots per weekday. So, what’s driving the longer hours? Could general practices be extending their hours to keep up with the booming urgent care market and attract pet owners after work, or simply offset declining revenue by maximizing service hours?

All practice types except companion animal predominant saw a slight decrease in gross revenue last year. However, when companion animal exclusive and companion animal predominant practices are grouped together, the overall revenue trends align more closely across the board. Not surprisingly, but certainly worth noting, is the substantial gap in median revenue: small animal veterinarians generate over $600,000, significantly outpacing all other practice types.

 Even with the highest ratio of full-time equivalent non-veterinarian staff per veterinarian, companion animal doctors are far ahead of their counterparts in revenue generation.

Here’s an interesting one: revenue for 100% brick-and-mortar practices took the biggest hit, while mobile practices experienced the most significant growth, highlighting a change in how and where pet owners are choosing to access care. Could mobile services be pulling clients away from traditional clinics? Definitely something to watch.

No survey is without gaps, and understanding the respondent pool helps put the results in perspective. Of the 524 practices surveyed, most were independently owned (93.9%) and 100% brick-and-mortar (56.6%). Meanwhile, the Mission Veterinary Partners and Southern Veterinary Partners merger just brought over 420 practices under one corporate umbrella. With groups estimated to own around 30% of US veterinary practices—and generating more than half of companion animal revenue—it’s fair to wonder if these numbers tell the whole story.

2025 AVMA Report on the Economic State of the Veterinary Profession. 

https://ebusiness.avma.org/ProductCatalog/product.aspx?ID=2215

Kogan LR, Rishniw M. Relief and mobile veterinary careers may offer a path towards improved quality of life. 

Javma-journal of The American Veterinary Medical Association

. Published online November 1, 2023:1-7. doi:

2024 AVMA Economic State of the Profession. https://ebusiness.avma.org/ProductCatalog/product.aspx?ID=2157

Wogan L. Veterinary relief practice is having a moment. Veterinary Information Network. Published August 1, 2022. Accessed March 31, 2025. https://news.vin.com/default.aspx?pid=210&Id=11050604&f5=1

Brick-and-mortar clinics are feeling the squeeze, mobile vets are thriving, and competition is heating up—veterinary practices are in for a dynamic year