Reduced incidence of tick paralysis cases in dogs and cats at two emergency clinics in South-East Queensland since 2015: new generation prophylactics as possible explanatory variables.

INTRODUCTION: This study aimed to determine the incidence of canine and feline tick paralysis cases presenting to two veterinary emergency hospitals before and after the introduction of new generation prophylactic acaricides. METHODS: This was a retrospective study, investigating the number of tick paralysis cases presenting to two emergency and critical care veterinary hospitals in South-East Queensland, from 2008 to 2021. A total of 10,914 dogs and 3696 cats were included over the course of the study. To assess if the introduction of new generation prophylactics in 2015 has coincided with any variation in case numbers, data for each species were analysed graphically and numerically in the first instance, then interrupted time series analyses were performed for the dog and cat data independently. RESULTS: Accounting for seasonal and climatic variation, we estimated a 54.8% reduction in dog (95% CI 45.3%-62.7%) and 44% reduction in cat (95% CI 19.5%-46%) tick paralysis cases presenting to these two clinics. This reduction corresponded with the timing of new generation prophylactic agents being introduced, including isoxazolines and imidacloprid/flumethrin impregnated collars. CONCLUSION: In the population studied, a significant reduction in the incidence of tick paralysis cases treated by veterinarians has occurred from 2015 onwards and was found to be associated with the timing of the release of new generation acaricidal products.

Acute kidney injury in 18 cats after subcutaneous meloxicam and an update on non-steroidal anti-inflammatory drug usage in feline patients in Australia.

OBJECTIVES: Acute kidney injury (AKI) is a well-known but poorly documented adverse effect of non-steroidal anti-inflammatory drugs (NSAIDs) in cats. We aimed to describe instances of NSAID-associated AKI in cats and survey Australian veterinarians on NSAID use in acute settings. METHODS: Medical records of cats that developed an AKI subsequent to the administration of meloxicam were obtained by searching the databases of seven practices in Queensland, as well as by contemporaneously contacting select veterinary colleagues of the authors in both general and specialist small animal practice. An online questionnaire was created for the survey, and the URL distributed to Australian practitioners. RESULTS: A total of 18 cases were retrieved, all of which received injectable meloxicam. The indication(s) for its use and the dosage prescribed were within the manufacturer's recommendations for Australian veterinarians. The majority of cases (13/18 cats) received the label dose of 0.3 mg/kg subcutaneously (SC) on the day of the procedure. In 12/18 cats, the injection was given in association with general anaesthesia or sedation. Fourteen cats survived to hospital discharge. Of 187 survey respondees, 89% routinely administered NSAIDs for surgery-related analgesia, with 98% prescribing meloxicam and 84% of these giving it SC. Ninety percent of respondees routinely administered NSAIDs for non-surgical-related analgesia, with 99% prescribing meloxicam and 35% of those giving it SC. CONCLUSIONS AND RELEVANCE: We strongly recommend that practitioners avoid prescribing meloxicam SC in cats. This recommendation is emphatic in situations where concurrent dehydration and/or hypotension are possible.

A review of 91 canine and feline red-bellied black snake (Pseudechis porphyriacus) envenomation cases and lessons for improved management.

INTRODUCTION: Most cases of red-bellied black snake (RBBS) envenomation in dogs respond favourably to treatment comprising of tiger-brown snake antivenom (TBAV), intravenous fluid therapy, analgesia and, if indicated, mechanical ventilation and/or blood transfusion. However, there remains a subset of patients who develop fatal complications despite intensive treatment and risk factors for these occurring remain unknown. Here we present a retrospective cross-sectional survey of 91 canine and feline RBBS envenomation cases. METHODS: Cases seen between June 2010 and June 2020 were retrieved from the databases of seven practices in South East and coastal Queensland. From the canine case population, logistic regression analysis was performed to assess the impact of potential risk factors at presentation on the likelihood of death. A final multivariable model was developed using a manual backwards elimination approach based on overall likelihood ratio tests and Wald chi-square P-values for each variable. Where model convergence failed due to quasi-complete separation, Firth's penalised maximum likelihood method was implemented. Such separation may occur when an outcome is completely predicted by an explanatory variable in one group. RESULTS: Of the 88 canine cases, 7 died (8.0%), all after prognosis-based euthanasia. Of the three feline cases, one died after unsuccessful resuscitation following cardiopulmonary arrest. Compared to survivors, dogs that died were older, exhibited pigmenturia, received antivenom later and had a higher total plasma protein (TPP), activated clotting time (ACT) and lower packed cell volume (PCV) at presentation.

Successful treatment of a potentially fatal eastern brown snake (Pseudonaja textilis) envenomation in a dog with tiger-brown snake antivenom with serial quantification of venom antigen and antivenom concentrations in serum and urine.

CASE REPORT: A successfully treated case of eastern brown snake (Pseudonaja textilis) envenomation in a Jack Russel Terrier dog is described with measurement of venom and antivenom concentration pre- and post-treatment. Early presentation, prompt administration of tiger-brown snake antivenom, hospitalisation and critical care monitoring lead to low morbidity and rapid recovery from a potentially fatal envenomation. Retrospective measurement of urine and serum venom and antivenom provided insight into the potential severity of the case and rapid efficacy of antivenom. CLINICAL SIGNIFICANCE: Potentially fatal brown snakebite cases may initially present with only mild clinical signs despite having high concentrations of venom and potential for fatal outcome. Prompt treatment with antivenom is essential to prevent the development of progressive and fatal coagulopathy and paralysis.

Severe metabolic acidosis due to acetazolamide intoxication in a dog.

CASE REPORT: This case report describes the clinical signs and case management of a 1-year-old neutered male Siberian Husky that accidentally ingested 635 mg/kg of oral acetazolamide (a carbonic anhydrase inhibitor). The dog presented with severe tachypnoea due to the development of hyperchloraemic metabolic acidosis and associated hypokalaemia that persisted for 7 days. Clinical and biochemical changes resolved with intravenous and subsequent oral supplementation of sodium bicarbonate and potassium. Complete recovery occurred within 9 days of presentation. CONCLUSION: To the authors' knowledge, this is the first case that reports overdosage of an oral carbonic anhydrase inhibitor in a dog and subsequent recovery with adequate supplementation and supportive care.

Red-bellied black snake (Pseudechis porphyriacus) envenomation in 17 dogs: clinical signs, coagulation changes, haematological abnormalities, venom antigen levels and outcomes following treatment with a tiger-brown snake antivenom.

BACKGROUND: This report describes 17 cases of red-bellied black snake envenomation (RBBS; Pseudechis porphyriacus) in dogs in south-eastern Queensland. Patients were prospectively enrolled for the treatment with a new tiger-brown snake antivenom 8000 units, (TBAV; Padula Serums Pty Ltd, VIC, Australia). CASE REPORT: Clinical diagnosis of RBBS envenomation was made by either snake venom detection kit, snake identification using scale counting, or owner observed dog-snake interaction in patients with clinical signs of envenomation. An RBBS venom antigen sandwich ELISA was used to retrospectively quantify venom levels in frozen serum and urine. Mechanical ventilation was required in 11% (2/17) patients, whole blood transfusion in 12% (2/17), tissue swelling at the bite site occurred in 53% (9/17) and facial palsy in 12% (2/17). One dog was euthanised, and overall, 94% (16/17) survived to hospital discharge. Clinicopathological changes pre-TBAV included variable haemolysis, increased CK, pigmenturia and mildly prolonged active clotting time with a median of 134 s (n = 13, range 91-206 s). Haematological profiles post envenomation revealed anaemia (6/6) and spherocytosis (5/5), which resolved without the use of corticosteroids. Pre-TBAV, median RBBS venom antigen concentration was 22.6 ng/mL (n = 15, range 2-128) in serum and 58 ng/mL (range 1-452) in urine; RBBS venom antigen was undetectable in serum post-TBAV in all patients. CONCLUSION: Some RBBS envenomed dogs required, critical care including mechanical ventilation, blood transfusion, additional antivenom and prolonged hospitalisation. TBAV was effective with excellent prognosis despite stated specificity for tiger and brown snake.

Tick paralysis in dogs and cats in Australia: treatment and prevention deliverables from 100 years of research.

This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all - a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.

Severe haemolysis and spherocytosis in a dog envenomed by a red-bellied black snake (Pseudechis porphyriacus) and successful treatment with a bivalent whole equine IgG antivenom and blood transfusion.

This case report describes a dog envenomed by a red-bellied black snake (RBBS; Pseudechis porphriacus) that experienced severe and life-threatening haemolysis. The dog presented with hypersalivation, facial swelling, mildly prolonged activated clotting time and the absence of neurological deficits. Envenomation was confirmed by positive identification of the snake and retrospective measurement of RBBS specific venom antigen (24 ng/mL) in serum. The dog was initially hospitalised, treated with intravenous fluids and one vial of tiger-brown snake antivenom which is recommended for RBBS envenomation in Australia. However, after 3.5 d the dog's PCV had declined to 15% and the dog was dull and tachycardic. A second vial of tiger-brown antivenom followed by a packed red blood cell transfusion was administered. A rapid clinical improvement within 12 h was observed. No free RBBS venom was detected in serum at any time point after the first vial of antivenom. Longitudinal haematology and biochemical profiling was performed to 62 d post-envenomation and revealed a gradual recovery in the haematocrit to normal reference range. Spherocyte numbers on blood smear were highest at 5 d post-envenomation and gradually declined to undetectable after 62 d. This case highlights the potential for unpredictable, severe and life-threatening anaemia resulting from RBBS envenomation in dogs.

Severe neurotoxicity requiring mechanical ventilation in a dog envenomed by a red-bellied black snake (Pseudechis porphyriacus) and successful treatment with an experimental bivalent whole equine IgG antivenom.

Snakebite in dogs from Pseudechis porphyriacus (red-bellied black snake; RBBS) is a common envenomation treated by veterinarians in Australia where this snake occurs. This case report describes the successful treatment of a clinically severe RBBS envenomation in a dog with an experimental bivalent equine whole IgG antivenom and mechanical ventilation, following its presentation in a cyanotic state. The cause of the cyanosis and respiratory distress was considered due to paralysis from neurotoxins in RBBS venom. The dog was treated with two vials of bivalent antivenom, each containing sufficient antivenom to neutralise the lethal effects of 40 mg of tiger snake (Notechis sp) and 40 mg of brown snake (Pseudonaja sp) venom. Hypoxaemia (Sp02 of 75%) and hypercapnia (PaCO2 of 61 mmHg) indicated the need for mechanical ventilation (MV) to prevent imminent death. The dog was anaesthetised using total intravenous anaesthesia and MV used for 18 h. Following discontinuation of MV, it resumed spontaneous breathing thereafter and made a complete recovery. Serum biochemistry revealed a significant myopathy with elevated CK and AST levels, peaking approximately 48 h post-treatment. Elevated liver enzymes, suggestive of hypoxic liver injury, were detected during the period of hospitalisation. The dog represented approximately one week after hospital discharge because of inappetence and mild hepatopathy, which resolved spontaneously by 30 d post-treatment. A mild coagulopathy was initially present which resolved within 24 h following antivenom treatment. At initial presentation, RBBS venom antigen was detected by sandwich ELISA in urine and serum. Free RBBS venom antigen was not detected post-antivenom treatment. Human cases of RBBS requiring ventilatory support are rare. This unusual case of RBBS envenomation in a dog highlights its potential clinical severity in dogs, and the need for early, aggressive, MV to achieve a successful outcome in cyanosed and clinically severe cases.

Eastern brown snake (Pseudonaja textilis) envenomation in dogs and cats: Clinical signs, coagulation changes, brown snake venom antigen levels and treatment with a novel caprylic acid fractionated bivalent whole IgG equine antivenom.

This report describes the diagnosis and treatment of 16 confirmed cases of snakebite from the Australian eastern brown snake (Pseudonaja textilis) in dogs and cats. The clinical signs, brown snake venom antigen concentrations, coagulation parameters, and treatment outcomes following administration of an experimental caprylic acid fractionated bivalent whole IgG antivenom are documented. A brown snake venom antigen specific sandwich ELISA was used to retrospectively quantify venom levels in serum and urine. The characteristic clinical signs of envenomation in all cases were neurotoxicity to a variable extent and coagulation disturbances. The median serum venom concentration at presentation was 122 ng/mL and ranged from 1.9 to 3607 ng/mL. The median urine venom concentration at presentation was 55 ng/mL and ranged from 3.3 to 2604 ng/mL. Mechanical ventilation was used to successfully support respiration in three severely paralysed cases for 1-30 h. In four cases where serum samples were available post-antivenom treatment, venom was no longer detectable. Coagulation parameters measured on citrated plasma samples collected prior to antivenom from each case were abnormally prolonged to variable degrees in all cases. Three cases (2 dogs; 1 cat) were euthanized within four hours of presentation for either cost based reasons (2) or poor prognosis (1). One dog developed massive and potentially fatal pulmonary haemorrhage and was euthanazed. In vitro testing of the venom procoagulant neutralising efficacy of the experimental antivenom demonstrated it was 9.6-72 times more effective when compared to two other commercial veterinary antivenom products. This is the first detailed report of a case series of P. textilis envenomation in dogs and cats. The envenomation syndrome in dogs and cats differed to that reported humans, dominated by neurotoxicity and coagulopathy; unlike in humans, where coagulopathy is of primary clinical significance.

Pregnancy outcomes after kidney donation.

The outcome of pregnancy in kidney donors has generally been viewed to be favorable. We determined fetal and maternal outcomes in a large cohort of kidney donors. A total of 2102 women have donated a kidney at our institution; 1589 donors responded to our pregnancy surveys; 1085 reported 3213 pregnancies and 504 reported none. Fetal and maternal outcomes in postdonation pregnancies were comparable to published rates in the general population. Postdonation (vs. predonation) pregnancies were associated with a lower likelihood of full-term deliveries (73.7% vs. 84.6%, p = 0.0004) and a higher likelihood of fetal loss (19.2% vs. 11.3%, p < 0.0001). Postdonation pregnancies were also associated with a higher risk of gestational diabetes (2.7% vs. 0.7%, p = 0.0001), gestational hypertension (5.7% vs. 0.6%, p < 0.0001), proteinuria (4.3% vs. 1.1%, p < 0.0001) and preeclampsia (5.5% vs. 0.8%, p < 0.0001). Women who had both pre- and post-donation pregnancies were also more likely to have these adverse maternal outcomes in their postdonation pregnancies. In this large survey of previous living donors in a single center, fetal and maternal outcomes and pregnancy outcomes after kidney donation were similar to those reported in the general population, but inferior to predonation pregnancy outcomes.

Deformation of the human brain induced by mild acceleration.

Rapid deformation of brain matter caused by skull acceleration is most likely the cause of concussion, as well as more severe traumatic brain injury (TBI). The inability to measure deformation directly has led to disagreement and confusion about the biomechanics of concussion and TBI. In the present study, brain deformation in human volunteers was measured directly during mild, but rapid, deceleration of the head (20-30 m/sec2 peak, approximately 40 msec duration), using an imaging technique originally developed to measure cardiac deformation. Magnetic resonance image sequences with imposed "tag" lines were obtained at high frame rates by repeating the deceleration and acquiring a subset of image data each repetition. Displacements of points on tag lines were used to estimate the Lagrangian strain tensor field. Qualitative (visual) and quantitative (strain) results illustrate clearly the deformation of brain matter due to occipital deceleration. Strains of 0.02-0.05 were typical during these events (0.05 strain corresponds roughly to a 5% change in the dimension of a local tissue element). Notably, compression in frontal regions and stretching in posterior regions were observed. The motion of the brain appears constrained by structures at the frontal base of the skull; it must pull away from such constraints before it can compress against the occipital bone. This mechanism is consistent with observations of contrecoup injury in occipital impact.

The anaerobic threshold in cystic fibrosis: comparison of V-slope method, lactate turn points, and Conconi test.

Physical exercise can improve sputum clearance in patients with cystic fibrosis (CF). To set up individual training protocols it is desirable to know the anaerobic threshold (AT). Established methods such as blood lactate measurements and ergometry can only be performed in specialized centers. Conconi showed that the heart rate threshold (HRT), i.e., the deflection point from the linear relationship between work load and heart rate, correlated significantly with the AT in healthy adults. To assess the reliability of the HRT in CF, we performed ergometry in 32 CF patients (mean age, 21.0 +/- 5.5 years; mean Shwachman score, 77.8 +/- 12.0) according to the Conconi protocol. The HRT was compared with the aerobic threshold (AeT) as determined by the V-slope method and with two turn points in the lactate performance curve (LTP1, LTP2). An HRT could be obtained in only 17 of the 32 patients (53%). In these 17 patients there was a significant correlation between HRT and the other thresholds, but the absolute values for the AT differed considerably: The mean HRT was 132% higher than the AeT according to Beaver, 107% higher than LTP1, and 19% higher than LTP2. Exercise protocols that rely solely on the HRT in CF will lead to excessive exertion during exercise training programs in these patients. According to these results the HRT of Conconi is not a suitable method to determine appropriate exercise levels in CF training programs and might even be harmful in CF patients. These results also indicate the need to test the reliability of a diagnostic procedure that has been developed only for healthy people.