Liz Bode

Replying to Sybil Dryburgh 23/10/2022 - 23:14

Hi both

Yes, this group originally did a retrospective study on this (although I’m not sure how you do a retrospective study about applying pressure and the presence or absence of a murmur!). They then went on to prove the concept with this prospective study.

In some cats, usually older and thinner cats, it is possible to place your stethoscope on the right parasternum and cause a low grade systolic murmur. The same goes with echo in some cats. When looking at the right ventricular outflow tract from the right side you can cause a dynamic obstruction due to the pressure of the probe. Another study (before we knew that some of these could be iatrogenic) back in 2004 showed that cats with dynamic right ventricular outflow tract obstruction didn’t have associated pathology or heart disease that would cause it. So, putting two and two together (and hopefully making 4) I think it would be safe to say that these cats probably don’t have pathology but due to their chest conformation you can push the heart against the opposite wall of the chest and deform the right outflow tract resulting in a murmur. When you release the pressure the murmur should disappear. Obviously, if it doesn’t disappear then another cause of the murmur might be present and if you’re not sure then echo is indicated.

I don’t think we know about dogs but I think the majority of dogs have too big a chest for this to be an issue (think how narrow cat chests are compared to a chihuahua even!)

Hopefully this answers your question but let me know if there are any others.

Liz

Replying to Kathryn B. 17/10/2022 - 16:19

Hi Kathryn,
Ooh drainage of big dogs like this can take AGES!!! I’d use a Mila chest drain in these cases as you’ll find them much faster and should reach further into the chest cavity as it probably was the length of your needle that was the limiting factor. You can suture them in for a few days. However, if you’ve drained the chest and it keeps recurring for longer term management I’d use a pleural port ideally (depending on the source of the effusion). A haemorrhagic effusion in a golden retriever doesn’t sound great 🙁

Replying to Emma Holt 06/10/2022 - 15:49

Hi Emma,

The cut-off for myocarditis is unclear, but I would be more suspicious if the cTNI was >1. I think most cardiologists go by this too. Generally they are well above this in the acute stages. It is good to be mindful that chronic myocarditis (at least in people) may have normal or only mildly elevated cTnI, but they usually have a DCM phenotype.

Liz

Replying to Kelly M. 27/09/2022 - 09:17

Hi

Thanks for the great questions and sorry for the delay in replying.

I think mediastinal disease is very difficult to identify too. If there’s fluid you get the Christmas tree appearance but solid masses either cause distortion of the mediastinum in specific regions or move things like the trachea (big lymph nodes for example). I’m afraid I don’t have any examples, I rarely encounter this probably because we CT most chests.

When laryngeal paralysis is secondary to hypothyroidism the signs may improve slightly with treatment but would rarely resolve completely. I don’t think we know enough about the mechanism of the disease to understand the relationship. I’d treat the hypothyroidism and monitor the laryngeal paralysis (unless very severe) but warn the owner it’s unlikely to resolve and may still get worse.

Historically we would have chosen metronidazole as part of a ‘four quadrant’ approach to severe AP. These days covering with co-amox will be sufficient for most pathogens and if severe cases or very poorly we would add in a fluoroquinolone. We rarely see pure anaerobes infecting the airways hence the lack of need for metro.

Hope that helps 🙂

Liz

Fab question!

There is no confirmed link in dogs but it is suspected and there are large scale studies in the USA currently.

The thoughts at the moment are that, for unknown reasons, some dogs on grain free diets that are high in peas, pulses or legumes may cause a DCM-phenotype. This is obviously not in all dogs that are consuming these diets, and we probably aren’t encountering it as frequently in the UK and Europe. However, if we are diagnosing a DCM phenotype in a dog that is on a grain free diet then one of our first recommendations is that the diet is changed to non grain free and a diet like Hill’s, RC or Purina etc that we know are complete and high quality. We would then expect to see improvements in systolic function over 3-6months.
If dogs are a breed predisposed to DCM that are on one of these diets then I’d still change the diet but the DCM phenotype is more likely genetic.

Liz

Replying to Kathryn B. 20/09/2022 - 13:21

Hi Kathryn,
Thanks for the lovely questions, I’ll do my best to answer but some of the areas are probably better answered by Scott, a gastroprotectant knowledge king! Sorry also for the delay, I’ve been away and just getting chance to answer now.

– in terms of antibiotic choice this isn’t a combination that I would be familiar with. In uncomplicated aspirations I would tend to stick to co-amox and then consider adding a fluoroquinolone if not as straightforward. Doxycycline does penetrate the airways really well and perhaps they were concerned about Mycoplasma as it is effective for that? Scott might also be able to shed some light here.

– In terms of omeprazole in brachys to reduce aspiration pneumonia I wouldn’t generally use it for this. However, I don’t think it’s straight forward at all and again Scott said he would put his thoughts here and might use it at the Q and A session.

– my preferred choice initially in dogs, if I knew they could be fidgety or slightly aggressive would be trazadone. In cats it would be gabapentin as you suggest. Then, for dogs it would be butorphanol IV or IM at 0.3mg/kg. This can work quite well. If wanting to do rads you’ll like need to add in alfaxalone IV. Cats don’t tend to respond as well to butorphanol so if use butorphanol and alfaxalone IV if possible but if not IM. See my answer to Viktoria for doses. Our anaesthetists tend to avoid midazolam for the reason you give, recovery can be bad and it isn’t very reliable. I think alfaxan has taken its place now and is much more reliable.

– I rarely perform inflated radiographs, I think we can see quite a bit of detail on digital images BUT there is often always interstitial pattern in under inflated rads so if the disease process is mild we might miss it. That being said if possible I would always follow a radiograph with a BAL and cytology which would pick up mild disease better than radiographs. If I were to use anaesthetic in this case for either a well or unwell dog I’d still choose butorphanol and alfaxalone. Although if you have to extubate for a BAL I would use propofol to maintain anaesthesia and so would then not use alfaxalone. We

Hope that helps 🙂 I’ll look forward to hearing Scott’s point of view too.

Liz

Replying to Mariska H. 15/09/2022 - 05:47

Hi,

This is a great question! Heart failure can be defined by the presence of fluid (as this is when the heart can no longer meet the requirements of the body), whether that’s pulmonary oedema or effusion. When an animal has heart failure they usually (with a few exceptions) have survival times less than a year and will have elevated respiratory rates in association with a cough.
Heart disease is progressive so over years the heart can have heart disease but mechanisms in the body, such as RAAS, are upregulated to maintain the efficiency of the heart and in reality it is only a very small percentage of animals that develop heart failure. So I would only ever use the term heart failure when there is fluid present.
In terms of the coughing dog, as I mentioned in the lecture furosemide might improve the cough as it has anti-tussive properties and may even shrink the left atrium by reducing blood volume and therefore left atrial pressure for some time (pimobendan will do the same). If owners finances would stretch to a point of care ultrasound to assess heart size and lungs then this would be preferable before starting furosemide ot pimobendan. If not, and the dog is coughing without an increase in respiratory rate, you could trial a course (10 days) of doxycycline. This is obviously antibacterial but also anti-inflammatory. If no improvement, or cough recurs, then again diagnostics are warranted but if not a short course of prednisolone at 1mg/kg for 2-3weeks could be initiated. Then inhaled steroids if an improvement to that.
Hope that clarifies things and helps.
Liz