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Previous Issue: Issue 16: January 2013
CONCURRENT MEDICAL CONDITIONS AND LONG-TERM OUTCOME IN DOGS WITH NONTRAUMATIC INTRACRANIAL HEMORRHAGE
Lowrie, M., De Risio, L., Dennis, R., Llabrés-Díaz, F. and Garosi, L. (2012), Veterinary Radiology & Ultrasound, 53: 381–388
Non-traumatic intracranial haemorrhage is one form of cerebrovascular accident (“stroke”). It usually occurs due to rupture of a blood vessel. This paper reviews the MRI characteristics of 75 dogs which had this condition. In 72 cases, the lesions were found to be intraparenchymal, with only 2 being subdural and one being intraventricular. A concurrent medical condition was identified in 33 cases. Angiostrongylus, lymphoma and meningioma were noted in dogs with solitary lesions, and in cases with multiple lesions, concurrent conditions included Angiostrongylus, metastatic neoplasia, septicaemia and hypertension. Of five dogs diagnosed with hypertension, two had hyperadrenocorticism, two had chronic kidney disease and one had hypothyroidism. Four of these cases died within 12 months. Of the other cases, many had a favourable long term outcome, especially those that had concurrent Angiostrongylus.
Bottom line: Non-traumatic intracranial haemorrhage is often associated with a concurrent condition. Long term outcome can be favourable in some cases.
Medial Humeral Epicondylitis in Cats
Streubel, R., Geyer, H. and Montavon, P. M. (2012), Veterinary Surgery, 41: 795–802
This prospective cohort study of 60 feline cadavers aimed to describe medial humeral epicondylitis in cats. Radiographs were taken of both elbows of 60 cats that had died or been euthanased. Those that showed evidence of new bone formation were examined histologically. 10% of cases were found to have evidence of bilateral new bone formation at the medial humeral epicondyle. Cartilage damage and tendinosis were also found in some cases. Two cases had signs of displacement and compression of the ulnar nerve.
Bottom line: This study suggests that medial humeral epicondylitis is common in cats, and can cause clinical problems.
Comparison of acetate tape impression with squeezing versus skin scraping for the diagnosis of canine demodicosis
Pereira, A., Pereira, S., Gremião, I., Campos, M. and Ferreira, A. (2012), Australian Veterinary Journal, 90: 448–450.
Demodicosis is a common parasitic skin disease, which is diagnosed on microscopy of skin samples. This study compared two techniques for detecting the mites, skin squeezing with an acetate tape impression versus deep skin scraping. 100% of cases studied had Demodex canis detected using the skin squeezing and acetate tape technique, compared to 90% with deep skin scrapings. This was significantly different.
Bottom line: Skin squeezing with acetate tape impression is more sensitive that skin scrapes in the diagnosis of demodicosis.
Nicotine hair concentrations in dogs exposed to environmental tobacco smoke: a pilot study
Knottenbelt, C. M., Bawazeer, S., Hammond, J., Mellor, D. and Watson, D. G. (2012), Journal of Small Animal Practice, 53: 623–626.
There is some evidence suggesting that exposure to environmental tobacco smoke can affect the health of pets. This study investigated whether dogs are exposed to significant amounts of environmental tobacco smoke in the home by testing the nicotine concentration in dog hair. Hair from 23 dogs exposed to environmental tobacco smoke was compared to 15 dogs which had been reported to have not been exposed. Hair was washed first to remove adhered nicotine, then nicotine concentration was measured. The results showed that dog hair nicotine concentration was strongly associated with reported exposure to environmental tobacco smoke. The levels of nicotine were similar to those reported in children. The authors suggest that analysis of dog hair could be a good way of estimating environmental tobacco smoke exposure in dogs and children.
Bottom Line: This study showed that dogs exposed to environmental tobacco smoke have significant concentrations of nicotine detectable in their hair.
The impact of acepromazine on the efficacy of crystalloid, dextran or ephedrine treatment in hypotensive dogs under isoflurane anesthesia
Sinclair, M. D. and Dyson, D. H. (2012), Veterinary Anaesthesia and Analgesia, 39: 563–573.
Acepromazine is commonly used in premedication protocols prior to general anaesthesia, or as part of a sedation protocol. This prospective, blinded, randomized, crossover study of six healthy adult dogs assessed the impact of acepromazine on the treatment of hypotension during anaesthesia. Anaesthesia was induced with propofol and maintained with isoflurane. Dogs randomly received acepromazine or saline, and end tidal isoflurane concentration was adjusted to induce hypotension. The dogs were then treated randomly with either dextran, lactated Ringer’s or ephedrine, and blood pressure was measured. Each dog received six treatments, which were separated by at least five days. The end tidal isoflurane concentration to achieve hypotension was significantly less in cases that received acepromazine. Lactated Ringer’s initially worsened hypotension due to vasodilation, and dextran led to minimal improvement in hypotension. Ephedrine adminstration led to an improvement in arterial blood pressure, cardiac output, oxygen content and delivery, but was associated with extremes in blood pressure that prevented the authors from recommending it at the studied dose.
Bottom Line: Acepromazine worsened the hypotensive effects of isoflurane, and administration of lactated Ringer’s significantly worsened this initially. Pre-treatment with acepromazine minimised improvement of blood pressure with all treatments studied.
Phase II clinical evaluation of lomustine chemotherapy for feline vaccine-associated sarcoma
Saba, C. F., Vail, D. M. and Thamm, D. H. (2012), Veterinary and Comparative Oncology, 10: 283–291
Feline vaccine-associated sarcoma is a rare but aggressive tumour which has been associated with injection sites. It has a high recurrence rate even after aggressive surgery. This study examined whether the addition of lomustine to the treatment regime could be effective. 28 cats with measurable vaccine associated sarcoma were treated every three weeks until the disease was noted to progress. Response rate was 25%. The median progression-free survival was 60 days. Haematological side effects were common, necessitating dose reductions and treatment delays.
Bottom Line: Lomustine may have a role in the treatment of vaccine-associated sarcoma, but safer dosing protocols are required.
Traumatic corneal laceration with associated lens capsule disruption: a retrospective study of 77 clinical cases from 1999 to 2009
Paulsen, M. E. and Kass, P. H. (2012), Veterinary Ophthalmology, 15: 355–368
Traumatic injuries to the eye can result in corneal laceration with disruption of the lens capsule. This can cause potentially vision-threatening complications. This study aimed to assess the prognostic factors in case of corneal laceration with disruption of the lens capsule, to help indicate whether lentectomy is indicated. 10 cats and 67 dogs with this injury were included in the study, 47 of which had acute injuries. 15 of these acute patients were treated with corneal repair and lens removal, 9 with corneal repair and no lens removal, and 23 with medical management only. Those cases treated surgically had a significantly greater rate of vision loss compared to those managed medically. After controlling for age and cause of injury, this was still significant in the cases that had corneal repair and lens removal compared to those treated medically. Delay between injury and referral, and length of corneal laceration were also prognostic factors. The authors conclude that medical management is an appropriate treatment in animals presenting with perforating corneal injuries with lens capsule disruption. Injuries warranted severe enough to require surgical intervention were associated with around 4 times the rate of vision-threatening complications compared to those treated medically. Good corneal wound apposition, lack of continued aqueous leakage and lack of uveal prolapse were considered to be good indications for medical management.
Bottom Line: Many cases of perforating corneal injury with lens capsule disruption may be better managed medically than surgically.
UNIQUE TOPOGRAPHIC DISTRIBUTION OF GREYHOUND NONSUPPURATIVE MENINGOENCEPHALITIS
Terzo, E., McConnell, J. F., Shiel, R. E., McAllister, H., Behr, S., Priestnall, S. L., Smith, K. C., Nolan, C. M. and Callanan, J. J. (2012), Veterinary Radiology & Ultrasound, 53: 636–642.
Meningoencephalitis is commonly encountered as a cause of neurological signs. Greyhounds suffer from a fatal idiopathic breed-associated form of the disease. Definitive diagnosis is by histological analysis, often at post mortem examination. This study describes the magnetic resonance imaging (MRI) findings in the disease. Four cases with confirmed greyhound nonsuppurative meningoencephalitis were included in the study. Lesions were found predominantly in the olfactory lobes and bulbs, the frontal and frontotemporal cortical grey matter, and the caudate nuclei. Lesions were hyperintense on T2 weighted series and isointense on T1 series, with minimal contrast enhancement.
Bottom Line: This study describes the MRI findings with greyhound nonsuppurative meningoencephalitis.
Ventricular response during lungeing exercise in horses with lone atrial fibrillation
Verheyen T, Decloedt A, Van der Vekens N, De Clercq D and van Loon G Equine Veterinary Journal
43 horses diagnosed with lone atrial fibrillation (no evidence of structural cardiac disease and otherwise healthy) underwent electrocardiogram examination during a standardised exercise test. Disproportionate tachycardia was noted in all horses with maximal heart rates ranging form
248-492 beats/min. QRS broadening and R on T phenomenon were common findings which may be regarded as a risk factor for exercise associated collapse or death. These findings were noted even at low levels of exercise and in some cases at rest. In this study the R on T phenomenon was common but did not progress to ventricular fibrillation suggesting a possible aberrant cause rather than ventricular ectopy.
Bottom Line: The bottom line: Dysrhythmias are common in horses with lone atrial fibrillation even at low levels of exercise which may contribute to weakness, exercise associated collapse and sudden death in horses with this condition.
Antimicrobial prescribing practice in UK equine veterinary practice
L.A. Hughes, G. Pinchbeck, R. Callaby, S. Dawson, P. Clegg and N. Williams Equine Veterinary Journal
This study determined the antimicrobial use patterns in horses in the UK.
Results from a postal questionnaire which posed clinical scenarios to veterinary surgeons in equine veterinary practice were used. It was found that less than 1% of respondents had a practice antimicrobial-use policy.
The most commonly prescribed antimicrobial was trimethoprim sulphonamides; 83% of respondents overdosed with this drug according to guidelines. Overall 56% of prescriptions were for a dose higher than the recommended rate. 11% of prescriptions were for antimicrobials not currently licensed for horses in the UK. The most common source of information regarding antimicrobial use was stated to be the NOAH compendium. Third and fourth generation cephalosporins were used less frequently and were more likely to be prescribed by those in referral practice. The majority of respondents failed to assess the weight of a horse using a weigh tape prior to prescribing an antimicrobial.
Bottom Line: Inaccurate dosing of antimicrobials is common in UK equine practice, even if the weight of the animal is known. Practice policies on antimicrobial use are uncommon but may improve antibiotic use in practice if introduced.