VETSCOPE

The dose of ephedrine is 0.02 to 0.1 mg/kg IV. Personally, I would repeat 0.02 mg/kg IV until blood pressure comes up. The indication of ephedrine is hypotension with bradycardia. It is especially effective for animals that do not respond to atropine. Ephedrine works well in hypothermic small dogs and cats although atropine may be ineffective in those. Although dilution is not particularly necessary, you can dilute when the volume is low. There is also no particular rate of administration, but ephedrine should be given slowly. The duration of action would be around 20 minutes. Adverse effects include tachycardia, hypertension, tachyarrhythmia, and ventricular premature complex. As the duration of action is short, undesirable effects disappear quickly. Thus, you let it go unless they turn into fatal arrhythmias with hypotension. In addition, you should pay attention to the depth of anesthesia, because ephedrine increase MAC of inhalants.

It is important to give the loading dose of fentanyl before the CRI. Please consider the loading dose of 5-10 ug/kg Fentanyl. You may also need to increase the dose of CRI if you want to significantly reduce the amount of isoflurane. Depending on the case, it may go up to 30 ug/kg/h. If it comes to this point, isoflurane can be maintained at less than 1%. However, side effects become stronger on dosage dependency. Firstly, you need a ventilator because of hypoventilation or apnoea. Secondly, atropine, glycopyrrolate, ephedrine, etc. may be required depending on the blood pressure as it can cause severe bradycardia. Finally, a patient may get excited when awakening, or become sensitive to light and noise, so it is important to reduce the dose of CRI to the range of 1-5 ug/kg/h, just before the end of anesthesia.

Hypoadrenocorticism in cats is very rare but you can find some literature on this topic. Most of the cats have undergone the diagnosis of hypoadrenocorticism based on an ACTH stimulation test using 0.125mg of synthetic ACTH via IV while observing the flat line before and after the stimulation. In dogs, Addison's disease cannot be completely ruled out when the baseline cortisol is under 2 (you need to do the full ACTH stimulation test), while the baseline cortisol above 2 can rule out Addison’s disease. We currently do not have such a diagnostic protocol established in cats. Since Addison's disease is very rare in cats, it may be best to perform the ACTH stimulation test to confirm the diagnosis rather than relying only on a single value of the baseline cortisol. Please feel free to contact your local internists regarding patients with complicated endocrinopathy if available.

It is commonly said that agitated/fractious dogs and cats can show high levels of PCV due to the contraction of the spleen. It is also known that the contraction of the spleen is caused by the release of epinephrine. One study in the 80s on cats published in AmJVetRes demonstrates that the existence of the spleen leads to a false increase in PCV levels (compared to splenectomized cats). Your cases seem to fit with the evidence above. As you probably have been doing, it is best not to change anything but to monitor the PCV levels longitudinally to monitor the patients as long as the patients are stable. However, it is important to make sure that you are not missing any concurrent conditions that can lead to dehydration (hence false increase in PCV) especially when your feline IMHA patients are on prednisolone; diabetes mellitus, pyelonephritis, the progression of underlying kidney disease, etc. Please feel free to contact your local veterinary internists if available.

Thank you for that information. Is she clinically affected by the hip dysplasia? Is she overweight? I would focus on daily low impact activity (leash walks) and maintaining leann body mass. If she is not painful there is no indication for a NSAID at this time. Omega-3 fatty acids and Glucosamine/Chondroitin could be helpful in maintaining joint health. If she is able to be this active and run I think doing that and checking our my webinar here on VetScope about therapeutic exercises in rehab would be helpful. Surgery does not seem indicated at this time.

Hi, Metronomic Chemotherapy is a great option for certain tumours where the owner cannot pursue more intense forms of chemotherapy or the ideal treatment modality is not available - It will not cause remission, but can reduce tumour growth enough to influence morbidity and mortality - which is all we want! I really like it for cases where tumour margins may be dirty and the owners cannot purse radiotherapy, or for cases such as diffuse haemangiosarc where our goal is reducing further metastasis! Chat to your local friendly oncologist, but it is a great option to have for your clients!

The digit lesion is very severe, and likely the only way to improve quality of life would be to amputate. However, additional lesions will develop in the near future (especially since 2 digits are already affected). To obtain a diagnosis, you could also consider a fine needle aspirate or biopsy under anesthesia. In my opinion, even without additional diagnostics, this is very suspicious for lung-digit syndrome and the cat’s prognosis is guarded to poor. Amputation of the digits will temporarily improve the quality of life, but the cat may have mobility issues postoperatively. Prior to removing them, I would recommend radiographs of the rest of the feet to rule out other lesions. If other lesions are present, my recommendation would be pain management of euthanasia, unfortunately.

Since the melanoma vaccine is not an option, I would consider carboplatin chemotherapy. There is conflicting information in the literature about the benefit of carboplatin, but one study showed a benefit. In addition, an older study showed that some dogs with bulky melanoma had a reduction in size with carboplatin.

For dogs with GI lymphoma I typically treat with UW-19/25. I don’t substitute vinblastine for vincristine unless it is not well tolerated. If the dog didn’t respond to the first vincristine treatment, I’d skip the second and go right to doxorubicin. Elspar is reasonable, but it tends to become less and less effective with each dose. I try to “save” it for when I need it, but would definitely use it as my first treatment since most GI lymphoma dogs are sick at the time of diagnosis. If the phenotyping confirmed T cell lymphoma then I would consider LOPP. The majority of dogs with GI lymphoma have a poor prognosis, but I have had a small number of them live >1 year.

Glaucoma is an increase in the IOP- intraocular pressure. There are various causes of glaucoma. In purebred dogs this is usually primary glaucoma – ie an abnormal drainage angle is a cause without other diseases. There is also secondary glaucoma ie with other diseases most commonly secondary to uveitis – inflammation. So the best glaucoma drop to use depends on the primary cause. For primary glaucoma – ie no other disease eg uveitis or lens luxation – then the prostanoids eg Latanoprost or Travatan are the go-to drugs. They usually work within 90 minutes. However, in some cases, these drugs may only work for 4 to 6 weeks. In some cases, we swap between the Latanoprost and the Travatan. These drops are normally used two to three times daily. In primary glaucoma we would also use a topical carbonic anhydrase inhibitor (CAI), these work through a different pathway so are additive to the prostanoids. REMEMBER that in primary glaucoma the other eye will be predisposed, in such a case we would do gonioscopy to check the drainage angle – if the drainage angle is abnormal we would use a topical CAI e.g. Cosopt ( dorzolamide and timolol) or Azarga (brinzolamide/timolol) 2 times daily. For secondary glaucoma, we would use a topical CAI e.g. Cosopt ( dorzolamide and timolol) or Azarga (brinzolamide/timolol) three times daily. In my experience, I do not find Timolol strong enough in dogs and cats with glaucoma. There are no combinations that you cannot use. In my experience, Alphagan and Glanatec are not used in animals. Remember that glaucoma in cats is most commonly secondary to uveitis. So in these cases, I will use a topical CAI without timolol eg Trusopt (dorzolamide) for Azopt (brinzolamide)