Influence of ketamine, propofol or isoflurane on intraocular pressure, heart rate and blood pressure in healthy dogs premedicated with medetomidine and midazolam.

BACKGROUND: According to the findings of several studies, sedatives and anaesthetics have different effects on the functioning of the cardiovascular system and intraocular pressure (IOP). For accurate diagnosis, treatment and surgery with minimal complications, it is necessary to be aware of the effects of sedatives and anaesthetics on the cardiovascular system and IOP. OBJECTIVES: The aim of this study was to evaluate the effects of sedatives (medetomidine and midazolam) and anaesthetics (ketamine, propofol and isoflurane) on IOP, heart rate (HR) and blood pressure in dogs. METHODS: In this study, 10 dogs participated in three treatments using a randomised cross-over design, with a 1-week washout period between each treatment. Dogs in all treatments were premedicated with medetomidine and midazolam. Anaesthesia was induced using ketamine, propofol, or isoflurane and maintained for 60 min with the appropriate doses of each drug. The cardiovascular variables (heart rate, and systolic, diastolic and mean arterial pressures) and IOP were measured at different timepoints: before premedication (baseline values, T-Bas), 15 min after medetomidine administration (T-Med), 20 min after midazolam administration (T-Mid) and at 15 (T-15), 30 (T-30), 45 (T-45) and 60 (T-60) min after anaesthesia induction. RESULTS: Medetomidine significantly reduced the IOP and HR and did not significantly change the mean arterial pressure (MAP). Midazolam significantly reduced the IOP while did not significantly change the HR and MAP. Ketamine and isoflurane significantly increased the IOP and HR while did not significantly change the MAP. Propofol significantly increased the HR, but did not cause significant changes in IOP and MAP. CONCLUSIONS: Considering that anaesthetics are typically administered in conjunction with pre-anaesthetic drugs, the increases in IOP induced by ketamine and isoflurane are not important, as the IOP did not exceed the baseline values. However, further studies are required to investigate these effects in patients with elevated IOP.

Prevalence of canine distemper in dogs referred to Veterinary Hospital of Ferdowsi University of Mashhad, Mashhad, Iran.

Canine distemper virus (CDV) is responsible for high morbidity and mortality in dogs worldwide. Epidemiological study of canine distemper can help to control and treat the disease in any area. This study aimed to investigate the prevalence of CDV in dogs referred to the Veterinary Hospital from September 23, 2018 to September 22, 2019. Dogs with at least two clinical signs of canine distemper underwent blood tests, rapid test kit from the eye and cerebrospinal fluid (CSF), and RT-PCR from whole blood and/or CSF samples. Out of 1212 referred dogs, 112 dogs were suspected to have canine distemper of which 90 underwent RT-PCR and rapid test kits. The disease prevalence was 4.04% (49/1212) and 7.44% (49/659) according to the total number of referring dogs and number of referring sick dogs, respectively. The distemper fatality rate was 69.57% (32/46). Seventy percent of distemper positive cases were under 12 months old and 52.08% were under 6 months old. Female dogs were more susceptible than males; however, the fatality rate of males was more than females. Of distemper positive dogs, 91.84% were unvaccinated. The highest prevalence (71.43%) of dogs diagnosed with CDV occurred during the cold seasons. It is concluded that canine distemper is endemic in the geographical area of Mashhad and its prevalence rate in dogs referred to the Veterinary Hospital of Ferdowsi University of Mashhad is 4.04% and its fatality rate is 69.57%. This indicates that a significant number of dogs may die if they develop distemper despite treatment.

Ultrasonographic measurement of the adrenal gland-to-abdominal aortic ratio as a valuable method of estimating normal adrenal size in rabbits.

A wide range has been reported for the ultrasonographic measurements of the normal adrenal gland in rabbits. Therefore, having sufficient information about the normal measurements of the adrenal gland and their relationship with indicators such as weight, sex and the diameter of the internal abdominal aorta will be of great help in diagnosing diseases of the adrenal gland. In the present study, 21 healthy adult intact rabbits were selected. The abdominal cavity of the animals was examined using ultrasound; adrenal gland parameters such as length, width, height, circumference and area on the right and left sides were measured in both sagittal and transverse planes. Additionally, the diameter of the abdominal aorta in the sagittal plane was imaged. After statistical analysis, the parameters of the adrenal glands on the right and left showed a positive significant correlation with the weight and the diameter of the abdominal aorta, although no significant correlation was found between these parameters and sex. The ratio of adrenal gland parameters to abdominal aortic diameter was calculated and the statistical analysis of the values showed that, except for the ratio of left adrenal area to aortic diameter, the other ratio of adrenal gland parameters to abdominal aortic diameter was not significantly related to weight. Therefore, these ratios can be used as suitable indicators for assessing the change in size of the adrenal gland of rabbits of different sizes. Knowing the relationship between normal adrenal measurements and the indices such as weight, sex and diameter of the abdominal aorta can help clinicians and researchers evaluate the changes in the size of the adrenal gland.

Effect of medetomidine, midazolam, ketamine, propofol and isoflurane on spinal reflexes in healthy dogs.

BACKGROUND: Sometimes it is necessary to use sedatives or even general anaesthetics to examine animals with spinal cord injuries. These drugs may affect spinal reflexes, alter the outcome of neurological examinations, and make it difficult to diagnose location of the lesion. OBJECTIVES: The aim of this study was to evaluate the effects of five pre-anaesthetic and anaesthetic agents commonly used in clinics on spinal reflexes in dogs. METHODS: Ten native adult dogs were participated in three groups. In all groups, the dogs were premedicated with medetomidine and midazolam; then, in the first group, ketamine, in the second group, propofol and in the third group, isoflurane were used for induction of anaesthesia. The spinal reflexes were evaluated before injection, 15 min after medetomidine, 20 min after midazolam, and at 15, 30, 45 and 60 min after induction of anaesthesia. RESULTS: Medetomidine did not reduce monosynaptic reflexes (patellar and cranial tibial reflexes) but increased them while it had no effect on the polysynaptic limb withdrawal reflexes. Midazolam had no effect on the spinal reflexes; Ketamine did not affect the patellar, cranial tibial and extensor carpi radialis reflexes, but reduced polysynaptic pain-related reflexes; and propofol and isoflurane abolished the all spinal reflexes. CONCLUSIONS: Medetomidine, midazolam and ketamine have no effect on reducing monosynaptic reflexes (patellar and cranial tibial reflexes) and may be used for neurological examination of restless animals in the clinic. Propofol and isoflurane eliminated all spinal reflex responses and are not suitable for neurological examinations.

The effects of age, sex, breed, diet, reproductive status and housing condition on the amounts of 25(OH) vitamin D in the serum of healthy dogs: Reference values.

BACKGROUND: Optimal amount of vitamin D for the proper functioning of the immune system is different from the required vitamin D amount for bones to prevent rickets. However, reports on vitamin D reference values in dogs are minimal, and there is still not enough information regarding the relationship between vitamin D and various variables such as disease, age, breed, diet type, and so on, as well as its relationship with haematological and serum biochemical parameters. OBGECTIVES: The present study aimed to determine reference values of 25(OH) Vit D in dogs and its concentration in different groups, categorized based on age, sex, breed, housing conditions, and diet, as well as 25(OH) Vit D relationship with hematology and serum biochemistry parameters. METHODS: In this study, 90 healthy dogs were selected to determine the reference value of 25 (OH) Vit D of serum after evaluating of their haematological and biochemical parameters to assess their general health. Dogs were divided into different groups according to above-mentioned variables. Serum 25 (OH) Vit D was subsequently measured by the ELISA method. RESULTS: The median concentration of 25 (OH) Vit D was 52.50 ng/ml with minimum and maximum amounts of 14.00 and 155.57 ng/ml, respectively. No significant difference was observed between 25 (OH) Vit D levels in the studied dogs regarding their different age, sex, breed, diet, housing condition, and reproductive status. Serum 25 (OH) Vit D concentration is directly correlated with the number of band neutrophils (p < 0.05). We also witnessed indirect correlations between serum 25 (OH) Vit D levels and the number of blood eosinophils and serum glucose (p < 0.05). CONCLUSION: In the present study age, sex, breed, housing condition and age had no significant effects on the amounts of 25(OH) vitamin D. According to correlations of vitamin D with MCH, band and eosinophil numbers and glucose, vitamin D may have a role in erythropoiesis and leukocytes response and also in energy metabolism in dog.

Detection of canine distemper virus in cerebrospinal fluid, whole blood and mucosal specimens of dogs with distemper using RT-PCR and immunochromatographic assays.

BACKGROUND: Accurate diagnosis of canine distemper (CD), a highly contagious and acute viral disease, cannot be made solely based on clinical signs and haematological findings, but serological and molecular methods compatible with clinical signs are also required. The type of sample and method of tissue sampling are also very important. Sometimes in chronic cases, the canine distemper virus (CDV) may not be detected in blood and conjunctival specimens but can be detected in cerebrospinal fluid (CSF). OBJECTIVES: The aim of this study was to evaluate and compare the suitability of CSF samples with whole blood and conjunctival samples in the detection of CDV. METHODS: The CDV was detected in CSF, whole blood and mucosal specimens in 20 dogs with obvious neurological with or without systemic signs congruous with CD by RT-PCR and rapid immunochromatographic (IC) antigen test kit assays. RESULTS: Rapid kit results were positive for mucosal swabs in 10 cases (50%) and for CSF in 17 cases (85%); RT-PCR results from whole blood were positive in 11 cases (55%) and from CSF in 16 cases (80%). CONCLUSIONS: Our results revealed that dogs with neurological signs showing simultaneous or recent systemic symptoms, whole blood, CSF and mucosal swabs are suitable for the diagnosis of CDV by RT-PCR and rapid IC antigen test kits, but dogs with neurological symptoms that are systematically asymptomatic or have had systemic signs for a long time, whole blood and mucosal swabs are not good samples while CSF is a good one.

Evaluation of Newcastle disease virus vaccine effectiveness in dogs with neurological signs of canine distemper.

Canine Distemper Virus (CDV) is the cause of a highly lethal infectious disease affecting a broad range of carnivores. Despite using various treatments, there is still no effective treatment, especially in the neurological form of distemper. The aim of this study was to evaluate the therapeutic effect of injecting Newcastle disease vaccine into the subarachnoid space of dogs with neurological form of distemper. The dogs that had symptoms of nervous distemper, particularly myoclonus, were included in the plan. After anesthetizing of dogs, 0.10 to 1.00 mL of cerebrospinal fluid (CSF) were removed and, 0.10 to 0.50 mL of the prepared Newcastle solution were injected into their subarachnoid space. Another 0.50 to 1.00 mL of normal saline was then injected to remove the needle from the vaccine. The live attenuated LaSota or B1 vaccine was used in this study. Rapid kit tests and reverse transcription polymerase chain reaction (RT-PCR) assays were used to diagnose of the disease. Dogs were monitored for up to 3 to 24 months during that time they were evaluated for improvement or worsening of clinical symptoms. Out of nine dogs in which distemper were diagnosed with different tests, one dog recovered completely and another dog recovered greatly. Therefore, the overall recovery rate was 22.20%. It is concluded that administration of Newcastle vaccine into the subarachnoid space of dogs with nervous distemper causes at least 22.20% improvement and does not cause specific side effects and can be used to treat affected dogs.

Effect of four local anesthetics (tetracaine, proparacaine, lidocaine, and bupivacaine) on intraocular pressure in dogs.

PURPOSE: To measure IOP in animals, it is often necessary to use topical anesthetics. The use of these drugs may cause changes in IOP and interfere with the final results. To address this issue, the effects of four local anesthetics (tetracaine, proparacaine, lidocaine, and bupivacaine) on IOP were investigated in ten adult dogs. METHODS: One drop of tetracaine was instilled in the right eye of half of the dogs and in the left eye of the other dogs; normal saline was instilled in the fellow eyes. The IOP in each dog was measured before and at 0, 5, 10, 15, 20, 25, 30, and 35 min after drug instillation using an electronic rebound tonometer. The effects of the other anesthetics were studied in the same way at intervals of at least 1 week. RESULTS: After instillation of tetracaine, the IOP decreased gradually, such that after 15 min, the IOP was significantly lower than the baseline (p = 0.022) and control values (p = 0.048). Proparacaine also reduced IOP after 10 min compared to baseline values (p = 0.046), but the two other drugs, bupivacaine and lidocaine, had no significant effect on IOP. The duration of eye anesthesia was 16, 20, 22, and 34 min for tetracaine, lidocaine, bupivacaine, and proparacaine, respectively. CONCLUSION: We recommend using drugs that combine inducing longer anesthesia with producing the smallest change in IOP, such as bupivacaine and, subsequently, lidocaine. Tetracaine and proparacaine have a significant effect on IOP, and if these drugs are used, this effect should be considered.

Treatment and long-term follow-up of cats with suspected primary epilepsy.

We report an evaluation of the treatment and outcome of cats with suspected primary epilepsy. Phenobarbital therapy was used alone or in combination with other anti-epileptic drugs. Outcome after treatment was evaluated mainly on the basis of number of seizures per year and categorised into four groups: seizure-free, good control (1-5 seizures per year), moderate control (6-10 seizures per year) and poor control (more than 10 seizures per year). About 40-50% of cases became seizure-free, 20-30% were considered good-to-moderately controlled and about 30% were poorly controlled depending on the year of treatment considered. The duration of seizure events after treatment decreased in 26/36 cats and was unchanged in eight cats. The subjective severity of seizure also decreased in 25 cats and was unchanged in nine cats. Twenty-six cats had a good quality of life, nine cats an impaired quality of life and one cat a bad quality of life. Despite being free of seizures for years, cessation of treatment may lead to recurrence of seizures in most cats.

Effect of tetracaine on intraocular pressure in normal and hypertensive rabbit eyes.

PURPOSE: To evaluate the effect of tetracaine on intraocular pressure (IOP) in normal and hypertensive rabbit eyes. METHODS: The study was conducted on 12 healthy rabbits as controls and 6 healthy rabbits in which an experimental model of ocular hypertension (OHT) was induced by administration of 70 mL/kg of tap water through an orogastric tube. One drop of tetracaine was instilled in the left eye while a drop of normal saline (placebo) was applied to the right eye of the control group. IOP was measured before and 0, 5, 10, 15, 20, 25, 30, 35 and 40 minutes after drop administration in this group. The OHT group also received one drop of tetracaine and normal saline in the left eyes and right eyes respectively, immediately after water loading; the instillation of drops was repeated after 55 minutes. IOP was measured before and 0, 5, 10, 15, 20, 25, 30, 35, 40, 55, 70, 85, 100 and 115 minutes after water loading in this group. RESULTS: Tetracaine treated eyes in both groups (ocular hypertensive and normal controls) demonstrated significant IOP reduction at time zero (immediately after drop instillation) which was sustained up to 20 minutes, as compared to placebo treated eyes (P<0.05). In ocular hypertensive rabbits, repeat instillation of tetracaine significantly reduced IOP at 55 minutes up to 30 minutes thereafter. CONCLUSION: Topical tetracaine can reduce IOP; this fact should be considered in experiments evaluating IOP reducing agents.

Effects of an unfixed combination of latanoprost and pilocarpine on the intraocular pressure and pupil size of normal dogs.

OBJECTIVE: To assess changes in intraocular pressure (IOP) and pupil diameter (PD) induced by daily application of an unfixed combination of latanoprost and pilocarpine in normal dogs. ANIMALS STUDIED: Fifteen mixed breed clinically normal dogs of both sexes. PROCEDURES: Three groups of five dogs each were administered in the right eye, one drop of 0.005% latanoprost (group L), 2% pilocarpine (group P), and 0.005% latanoprost with 2% pilocarpine (group LP), respectively. The left eyes received placebo. Drugs were administered once a day at 8 a.m. over a period of 5 days. IOP and PD measurements were conducted daily at 8 a.m., 10 a.m., 12 noon, 2 p.m., and 4 p.m. from 1 day preceding treatment to 7 days following treatment, and the presence of blepharospasm and/or conjunctival hyperemia was noted. RESULTS: Compared to baseline values, mean diurnal IOPs significantly decreased during the treatment period, by 4.4 (24.4%), 5.8 (31.4%), and 6.1 mmHg (35%) in the L, P, and LP groups, respectively. Compared to placebo-treated eyes, reductions of 2.1(14.1%), 3.2 (20.1%), and 4.1 mmHg (26.6%) were observed for the L, P, and LP groups, respectively. Although mean IOPs in the LP group decreased slightly more than the other two groups, these differences were not statistically significant. Miosis and conjunctival hyperemia were observed in the treated eyes of all three groups of animals during the treatment period. CONCLUSIONS: Although both 0.005% latanoprost and 2% pilocarpine individually produced significant decrease in IOP, the topical administration of a combination of latanoprost (0.005%) and pilocarpine (2%) was not associated with a statistically significant synergistic reduction in IOP in dogs; and miosis was the most frequent side effect observed during treatment.

Effect of different treatment regimen with dexamethasone and acetylcysteine on corneal wound healing in rabbits.

BACKGROUND: The effect of corticosteroid therapy on corneal wound healing is controversial. The objective of this study was to evaluate the effects of combination therapy with dexamethasone and acetylcysteine at different times and durations on experimentally-induced corneal wounds and haze in rabbits. METHODS: Eighteen adult New Zealand white rabbits were divided into three groups of six each. Under anesthesia corneal wounds were created surgically in the center of all eyes. The right eyes of rabbits in group 1 were treated topically with acetylcysteine and dexamethasone immediately after surgery, those in group 2 were treated with acetylcysteine from day 1 and with acetylcysteine and dexamethasone from day 8, and those in group 3 were treated with acetylcysteine from day 1 and with acetylcysteine and dexamethasone from day 15. The left eyes were assigned as controls and were treated with normal saline. All eyes were treated six times a day for 28 days. Corneal wounds were measured by fluorescein staining every day. RESULTS: The combination of acetylcysteine and dexamethasone in group 1 significantly increased mean healing time, but did not change that in groups 2 and 3. Clinical and histopathologic examinations revealed that one month after the ulceration in groups 1 corneal haze was greater in treated than in the control eyes. Moreover, there was no significant difference between the control and treated eyes of group 1, 2, or 3 in terms of corneal haze at two or three months after the ulceration. CONCLUSIONS: The findings of the present study show that the association of 3% concentration of NAC and 0.1% concentration of dexamethasone immediately after corneal ulceration can delay corneal wound healing, and consequently produce more corneal haze. Thus, the use of 0.1% concentration of dexamethasone should be delayed at least until the completion of the epithelial defects.

Clinical comparison of primary versus secondary epilepsy in 125 cats.

In the present study 125 cats with recurrent seizures were analysed. The main goal was to investigate the aetiology and compare primary epilepsy (PE) with secondary epilepsy (SE) regarding signalment, history, ictal pattern, clinical and neurological findings. Seizure aetiology was classified as PE in 47 (38%) and SE in 78 (62%) cats. SE was caused mainly by intracranial neoplasia (16), hippocampal necrosis (14), toxicosis (eight), and encephalitis (seven). A significant difference between PE and SE was found in: age, body weight, duration of seizure, occurrence of status epilepticus and neurological deficits. Status epilepticus, altered interictal neurological status and seizure onset over the age of 7 years indicated SE more frequently than PE. If the seizures occurred during resting conditions and rapid running occurred the aetiology was more likely to be PE than SE.