89 | 5 essential tips to help you care for dogs with tetanus as a veterinary nurse

NursingPodcastEmergency and Critical CareNeurology
Written By Laura Jones

This week, we’re looking at another less common, but really challenging disease to care for - tetanus infection in dogs and cats.

The first tetanus case I ever saw was as a locum nurse at an out-of-hours hospital. The vet and I are examining this dog, who was starting to become stiff and had the classic tetanus grin, knowing we needed to refer them ASAP before things got a lot worse.

And now that I’m in referral practice, I see the other side of this. I see our ICU nurses working tirelessly to support these patients, using countless skills in the process, and making all the difference in how these patients recover.

Caused by the neurotoxin-producing bacterium Clostridium tetani, this disease might be uncommon, but it’s life-threatening, and it needs early recognition, aggressive management, and really intensive nursing to give patients the best chance of survival.

But to do that well, we need to understand how tetanus affects our patients, and the interventions they need to recover - and that’s exactly what we’re talking about today.

So, what is tetanus, and how does it affect dogs and cats?

Tetanus is a neurological disease caused by a potent neurotoxin called tetanospasmin, produced by the bacterium Clostridium tetani. 

This is an anaerobic, spore-forming pathogen that is found everywhere in the environment, including soil, dust, and even in faeces. 

When C. tetani enters the body (usually through a wound), it begins producing tetanospasmin.

This toxin enters peripheral nerves and travels retrogradely (in the opposite direction) along the axons to the spinal cord and brainstem, where it interferes with the release of inhibitory neurotransmitters, such as GABA and glycine. 

Without these neurotransmitters, the motor neurons fire uncontrollably, resulting in persistent muscle contractions, rigidity, and spasms.

The sensitivity to the toxin varies between species. Horses and humans are highly susceptible, which is why they’re routinely vaccinated. Dogs and cats are less sensitive, with lethal doses many times higher than those of other species. However, when they do develop tetanus, it can be severe (and even sometimes fatal).

In dogs, the most common presentation is generalised tetanus, where patients present with widespread muscle stiffness, dysphagia, and often autonomic complications. 

Infection is possible in cats, but the disease tends to be localised, affecting just the limb or area near the wound. So if you’ve got a nasty tetanus case in, chances are you’re dealing with a dog - and because of that, we’re going to focus primarily on canine tetanus infection in this episode.

Ok, so that’s what tetanus is. But how do dogs get infected?

In most cases, the source is a wound - especially one that’s deep, penetrating, or poorly oxygenated, because the anaerobic C. tetani bacteria thrive in that environment. 

In fact, a recent retrospective study found that around 89% of dogs had an identifiable wound at the time of diagnosis. Most of these were in the digits, footpads, or pelvic limbs, and many required surgical revision or even amputation due to osteomyelitis and infection.

Clostridial spores can survive in the environment for several years; therefore, even seemingly minor injuries, such as nail bed trauma or a small healing laceration, can serve as entry points. 

Some dogs have even developed tetanus following teething, others after surgery, and a few without any obvious trauma at all.

The average time from wound to onset of clinical signs is approximately 6 to 10 days, but this can vary from a few days to nearly a month.

What clinical signs do we see in dogs with tetanus?

The initial signs are often subtle and can be challenging to spot, but there are also some specific signs that we commonly observe in tetanus patients. This means that knowing what to look for is essential, so that you can treat promptly and minimise deterioration. 

Most dogs with tetanus initially exhibit oculofacial signs, characterised by changes to their eyes, jaw, and facial muscles. These signs include:

  • Trismus, or jaw stiffness

  • Risus sardonicus, (a quite creepy-looking fixed grin, from facial muscle spasm)

  • Prolapsed third eyelids

  • Stiff, pricked ears

  • Photophobia or hypersensitivity to noise and touch

As the disease progresses, we see more generalised clinical signs, such as:

  • Generalised muscle rigidity

  • A classic ‘sawhorse stance’ (where the limbs are ‘stuck’ in rigid extension)

  • Dysphagia, hypersalivation, and regurgitation or vomiting

Advanced cases often develop muscle spasms, rapid muscle twitches known as fasciculations, or even seizures. And in really severe cases, patients will develop signs of autonomic dysfunction.

The autonomic nervous system is responsible for regulating involuntary bodily processes. It controls functions such as heart rate, blood pressure, respiration, and digestion. Therefore, if patients develop autonomic dysfunction, bradycardia, cardiac arrhythmias, urinary retention, ileus, hypertension, or even respiratory arrest can occur.

Some dogs, particularly those recovering from infection, will display signs of REM sleep behaviour disorder. Patients may exhibit various behaviours during sleep, including paddling, twitching, running, vocalising, and even biting, with approximately 46% of tetanus patients affected in one study. Signs are usually transient, but can persist for up to 6 months in some cases.

So, those are the signs that we see, but how do we diagnose tetanus in dogs?

The biggest challenge is that there’s no single test that confirms tetanus.

For this reason, diagnosis is almost always made based on the patient’s presenting signs, along with documenting a wound (in most, but not all cases) on examination. 

Bloodwork and imaging may be unremarkable or show increases in creatine kinase (CK) and AST. Culturing C. tetani from a wound is extremely difficult and rarely successful, so it is not commonly performed.

Diagnostic imaging may be performed to assess for complications like aspiration pneumonia or megaoesophagus, and EMG or nerve conduction may be used to rule out other neuromuscular diseases that could explain the patient’s clinical signs.

Serum antibody titres to tetanus toxin can theoretically be measured, but values must be compared with a control patient, and this test is very rarely performed in practice.

What about treating tetanus - where do we come in as veterinary nurses?!

Treating the tetanus patient isn’t easy. They require intensive supportive care alongside treating the initial source of infection and reducing toxin production. The main goals of tetanus management are:

  1. To eliminate the source of infection

  2. To neutralise the circulating toxin

  3. To manage the patient’s muscle rigidity and spasms

  4. To support organ function and prevent complications

How to manage a tetanus patient with a wound

If a wound is still active, it should be surgically debrided. In many cases, this means amputation of the affected digit. Some dogs received local injections of antitoxin along the wound margins before surgery.

Alongside wound management, treatment includes antibiotics, antitoxin and supportive care.

Tetanus antitoxin (TAT) can also be administered systemically; however, its use is limited if the tetanus toxin has already bound to nerve cells. The earlier it’s given, the more chance it has to bind to the unbound toxin, but it isn’t risk-free, and there’s a chance of reaction - so many dogs receive a test dose first.

Antibiotics (especially metronidazole) are used to kill the bacteria. Often, a second antibiotic, such as amoxicillin-clavulanate, is added if there’s concurrent pneumonia or a wound infection.

Sedation and muscle relaxation are essential. Most dogs require a combination of sedative and muscle relaxant agents, depending on their clinical signs. These include CRIs of benzodiazepines, dexmedetomidine or even propofol, and methocarbamol - a centrally-acting muscle relaxant.

Sedation isn’t just for comfort in these patients, though, of course, that is really important. Movement, sound and light can very easily trigger spasms, so minimising stimulation and movement is vital.

And how will we support these patients as nurses and technicians?

Nursing care can make or break a tetanus recovery, and I am not exaggerating. These patients need intensive management, and they’re incredibly challenging - but also really rewarding - to nurse.

I want to leave you with five key nursing steps you can implement in practice to give better care to these patients: recumbency care, environmental management, nutrition, elimination, and airway management.

First up is recumbency management. 

Many of these patients are recumbent, so they need careful management of their mobility, including turning every 4 hours, using appropriate bedding and neutral limb positioning to minimise pressure sores, and physiotherapy to aid muscle contracture.

Second, we need to consider the environment in which these patients are housed.

These patients require quiet, dark areas with minimal disruption, while still ensuring adequate monitoring. Earplugs, cage covers, limiting patient interaction and handling, and preventing unnecessary movement are essential.

Third, there’s nutrition and hydration.

Most dogs with tetanus cannot eat or drink safely - due to a combination of recumbency, sedation, gastrointestinal dysmotility and an inability to open the mouth/swallow.

Most patients will require a PEG tube (or possibly parenteral nutrition in severe cases) to meet their energy needs, with oral feeding and water reintroduced only once the patient is stable and able to swallow.

Both feeding tubes and parenteral nutrition solutions need careful management (especially parenteral nutrition) - including careful aseptic technique and monitoring in administration to feeding.

Fluid therapy will be necessary to maintain hydration, depending on the patient’s enteral water intake. Their fluid balance should be closely monitored, and rates adjusted as required.

Fourth, we need to manage their bladder and bowel function.

Autonomic dysfunction means that ileus, constipation and urinary retention are common in tetanus patients. 

Bladder expression or catheterisation may be needed to prevent retention or overflow incontinence and soiling. Urinary catheters can be placed by nurses and technicians, and need to be managed carefully to prevent complications such as hospital-acquired urinary tract infection (UTI).

Patients with reduced gastrointestinal motility and/or those receiving sedatives are likely to be constipated, so monitoring defecation and administering enemas as needed is an important nursing consideration.

And fifth, make sure to protect the airways.

The muscle spasms associated with tetanus can affect the laryngeal muscles and the diaphragm, making breathing very challenging. On top of this, megaoesophagus, dysphagia and regurgitation are common, meaning patients are at a very high risk of aspiration pneumonia, laryngeal spasm, and hypoventilation. 

Oxygen therapy (usually high-flow oxygen therapy or mechanical ventilation) is often indicated, and with this comes a significant amount of intensive nursing care, including aseptic technique, oral care, specialised sensory care, humidification, and continuous monitoring.

In addition, tetanus patients need to be protected against aspiration by using postural feeding, appropriate positioning, and considering how (or if) the patient is fed.

Tetanus may be rare, but when we encounter it, we must act quickly - and it’s the care we provide as nurses and technicians that makes all the difference. From recumbent patient care to nutrition, minimising stimulation, bladder management, rehabilitation, and everything in between, we play an essential role in their recovery. 

We used to think that tetanus was a condition for which patients had a 50/50 chance of recovery, but a more recent study has shown that survival rates have increased to around 89%, in no small part due to the care we provide. 

That’s it for this week’s episode. I hope it has helped you feel more prepared and confident about caring for patients with tetanus, whether you’ve seen one before or not, and provided you with a list of skills you can use when doing so.

Did you enjoy this episode? If so, I’d love to hear what you think. Take a screenshot and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!


References and Further Reading

Laura Jones
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