Behavioral and cardiopulmonary effects of dexmedetomidine alone and in combination with butorphanol, methadone, morphine or tramadol in conscious sheep

Objective: To compare cardiopulmonary and sedative effects following administration of dexmedetomidine alone or with butorphanol, methadone, morphine or tramadol in healthy sheep. Study design: Randomized crossover study. Animals: Six Santa Inês sheep, five females, one male, aged 12–28 months and weighing 40.1 ± 6.2 kg. Methods: Sheep were assigned treatments of dexmedetomidine (0.005 mg kg−1; D); D and butorphanol (0.15 mg kg−1; DB); D and methadone (0.5 mg kg−1; DM); D and morphine (0.5 mg kg−1; DMO); or D and tramadol (5.0 mg kg−1; DT). All drugs were administered intravenously with at least 7 days between each treatment. Rectal temperature, heart rate (HR), respiratory rate (fR), invasive arterial pressure, blood gases and electrolytes were measured prior to administration of drugs (baseline, T0) and every 15 minutes following drug administration for 120 minutes (T15–T120). Sedation was scored by three observers blinded to treatment. Results: HR decreased in all treatments and fR decreased in DM at T30 and DMO at T30 and T45. PaCO2 was increased in D, DB and DM compared with baseline, and PaO2 decreased in D at T15 and T45; in DB at T15 to T75; in DM at T15 to T60; in DMO at T15; and in DT at T15, T30 and T75. There was a decrease in temperature in D, DB and DM. An increased pH was measured in D at all time points and in DT at T30–T120. inline image and base excess were increased in all treatments compared with baseline. There were no statistical differences in sedation scores. Conclusions and clinical relevance: The combination of dexmedetomidine with butorphanol, methadone, morphine or tramadol resulted in similar changes in cardiopulmonary function and did not improve sedation when compared with dexmedetomidine alone

Effects of pneumoperitoneum and trendelenburg position on intraocular pressure (IOP) in isofluorane anesthetised cats

The aim of this study was to determine whether a pneumoperitoneum of 10 mmHg combined or not with the Trendelenburg position could lead to significant changes in intraocular pressure (IOP), ocular pressure perfusion (OPP), and cardiorespiratory variables; as well as determine whether a correlation exists between IOP and mean arterial blood pressure (MAP), and/or partial pressure of carbon dioxide in arterial blood (PaCO2) in cats. Animals were allocated in two groups (n=7/group): GC (without inclination) and GTREN (Trendelenburg position). The variables were recorded before (baseline) and during 30 minutes (T5-T30) after insufflation. In GTREN, a reduction in heart rate was observed at T5 and in respiratory rate at T5 and T15. There was an increase in IOP at T5-T30 in comparison to baseline. There was a reduction in potential of hydrogen in arterial blood in both groups at all times in comparison to baseline. Partial pressure of carbon dioxide in arterial blood was increased at T15-T30 in GC and at T5-T30 in GTREN. In conclusion, the pneumoperitoneum of 10mmHg CO2 did not significantly affect IOP or OPP in cats anaesthetised with isofluorane and kept under spontaneous ventilation. However, induced pneumoperitoneum combined with Trendelenburg position resulted in an increase in IOP in cats subjected to the same anaesthetic conditions, but did not affect OPP

Splenic congestion associated with acepromazine administration in dogs

The aim of this study was evaluate splenic dilatation induced by acepromazine in a prospective, randomized study. Thirty-three adult mongrel dog were divided into two groups designated as AG (acepromazine 0.05 mg/kg, i.v., n = 23) and CG (0.9% sodium chloride administered at a similar volume, n = 10). In both groups underwent sonographic examinations before (T0) and fifteen minutes (T15) after drug injection. The thickness spleen and splenic vein width were measured. Higher thickness was found in the AG group at T15 (2.47 cm) when compared to that at T0 (2.06 cm, p = 0.016), while the T0 (2.33 cm) and T15 (2.39 cm) measures did not differ within the CG group. Moreover, the splenic vein width was higher (p = 0.013) at T15 than at T0 in the AG group. Based on results of this study, we concluded that acepromazine, in doses of 0.05 mg/kg, promotes splenomegaly in dogs after fifteen minutes of the injection

Inhalation anesthesia in sheep: comparative research of halothane, isoflurane and sevoflurane

Foram utilizados vinte ovinos, machos com idade entre um e três anos, com peso médio de 33,1 ± 3,1 kg. Os animais foram distribuídos de forma aleatória em três grupos, designados como GH (halotano), GI (isofluorano) e GS (sevofluorano) em experimento do tipo cruzado com intervalo mínimo de 1 semana entre os tratamentos. Numa primeira etapa, os animais foram anestesiados com auxílio de máscara facial, intubados e mantidos sob anestesia com agente segundo a determinação de cada grupo e obtida a concentração alveolar mínima (CAM) dos agentes por meio de estímulo nociceptivo com eletroestimulação. Em uma segunda etapa, os animais foram mantidos com a CAM previamente compreendendo os momentos de M0 a M8 com intervalo de 15 minutos entre os mesmo. Foram avaliadas as funções hemodinâmicas, respiratórias, hemogasométricas, endócrinas e o índice biespectral. Os valores médios de CAM foram de 0,71 ± 0,09%, 1,31 ± 0,33% e 2,69 ± 0,29% para o halotano, isofluorano e sevofluorano respectivamente. Houve redução dos valores do índice cardíaco no GI em todos os momentos comparativamente ao basal (p<0,001); na comparação entre os grupos os valores do M0 no GI foram superiores aos verificados em GH e GS (p<0,01). O valores do volume e índice sistólico foram inferiores ao basal a partir de M6 no grupo GH (p<0,05) e no GI todos os momentos foram inferiores ao basal (p<0,001); na comparação entre os grupos verificou-se que os valores dessas variáveis no momento M0 no GI foram superiores a GH (p<0,05) e GS (p<0,001). As médias da pressão venosa central foram inferiores no grupo GH em todos os momentos comparativamente a M0 (p<0,001), e neste mesmo momento, as médias foram superioriores comparativamente aos outros grupos (p<0,05). Quanto ao índice de resistência vascular sistêmica, os valores foram superiores nos momentos M6, M3 e M7 nos grupos GH (p<0,05), GI (p<0,001) e GS (p<0,01), respectivamente; houve incremento do índice de resistência vascular periférica no momento M7 (p<0,01) no grupo GH a partir de M3 (p<0,001), em GI e em M7 e M8 (p<0,05) comparativamente ao basal. Os valores de tensão de dióxido de carbono no final da expiração foram superiores no grupo GH a partir de M4 (p<0,05) e no GI a partir de M3 (p<0,01) comparativamente ao basal. Os valores do índice biespectral no GI, foram superiores a partir de M5 em relação ao valor basal (p<0,01); na comparação entre os grupos, os momentos M2 e M3 foram inferiores no GI comparativamente ao GH e GS (p<0,05). Houve redução da temperatura retal em todos os grupos e momentos comparativamente ao valor basal (p<0,001). O período de recuperação foi superior no grupo GH (p<0,05). Nas condições do presente estudo a CAM em ovinos é de 0,71%, 1,31% e 2,69% para o halotano, isofluorano e sevofluorano respectivamente; os três agentes promovem redução do débito cardíaco e do volume sistólico; os valores do índice biespectral são semelhantes entre os fármacos, com valores inferiores quando tratados com isofluorano; há indução de estresse neuroendócrino avaliado por meio da dosagem de cortisol; os agentes promovem hipotermia tempo dependente; o halotano promove recuperação anestésica mais prolongada.Twenty sheep, all males, were used in this experiment. Age ranged from one to three years and mean weight was 33.1 ± 3.1 kg. In a crossover design, animals were randomly treated with halothane (GH), isoflurane (GI) and sevoflurane (GS), with interval of 1 week between treatments. In a first phase, anesthesia was induced by facemask, animals were then intubated and anesthesia maintained with one of the three treatments. Minimum alveolar concentration (MAC) was obtained by nociceptive stimulation for each animal. In phase 2, the animals were anesthetized again by facemask and maintained at the predetermined MAC (Phase 1) for two hours. Data was collected at moments (M0-M8) with intervals of 15 minutes. Cardiovascular, respiratory and bispectral index parameters were recorded. Blood gas analysis, CBC and cortisol levels were also measured and recorded. MAC of each group were 0.71± 0.09%, 1.31 ± 0.33% e 2.69 ± 0.29% for GH, GI and GS respectively. There was a reduction in cardiac index in GI at all times compared to baseline (p<0.001). Among groups the values of M0 in GI were higher than those in GH and GS (p<0.01). In GH, the end systolic volume and stroke index were lower than baseline from M6 until the end of the experiment (p<0.05). In GI, ESV and SI were below the baseline at all times (p<0.001). Among groups it was found that the GI baseline values of these variables were higher than GH (p<0.05) and GS (p<0.001). The mean central venous pressure were lower in the GH group at all times compared to M0 (p<0.001), which was higher than the baseline of the other groups (p<0.05). When compared to baseline, systemic vascular resistance index was higher in the moments M6, M3 and M7 in GH (p<0.05), GI (p<0.001) and GS (p<0.01), respectively. There was an increase in peripheral vascular resistance index (PVRI) at the time M7 (p<0.01) in GH from M3 to the end of the study (p<0.001). In GI, PVRI was increased at M7 and M8 (p<0.05) in comparison to baseline. The values of end-tidal of carbon dioxide were higher than baseline in the GH group from M4 (p<0.05) until the end of study. The same occurred in GI starting at M3 (p<0.01). In GI, the bispectral index values were higher starting at M5 to the end when compared to baseline (p<0.01). Among groups, BIS was lower at M2 and M3 in GI when compared to GH and GS (p< 0.05). Rectal temperature decreased in all groups at all moments in comparison to baseline (p<0.001). The recovery period was longer in GH (p<0.05). Under this study conditions MAC in sheep were 0.71%, 1.31% and 2.69% for halothane, isoflurane and sevoflurane, respectively. All treatments further reduced cardiac output and stroke volume; bispectral index values were similar among drugs, with lower values when treated with isoflurane. A stress response was believed to be induced due to elevation of serum cortisol in all groups. These inhalants promote time-dependent hypothermia. Halothane anesthesia promotes prolonged recovery

Spina bifida in a dead stillbirth mongrel dog

 A espinha bífida é uma deformidade congênita caracterizada pelo incompleto fechamento da porção dorsal de uma ou mais vértebras. O presente caso descreve as alterações radiológicas e patológicas de um cão natimorto sem raça definida. O animal apresentava uma fissura nas vértebras torácicas, resultando em exposição e protusão da medula espinhal e meninges. O exame radiográfico simples em posição ventro dorsal das vértebras revelou defeito na fusão do processo espinhoso das vértebras torácicas (T6-T13), enquanto na radiografia lateral foi observada cifose em toda região lombar.Spina bifida is a congenital spinal deformity that is characterized by an incomplete closure of the dorsal portion of the vertebrate. This report describes the radiological and pathological findings of this abnormality in a dead still birth mongrel. The dog demonstrated a cleft at the dorsal region of the thoracic vertebrate column, which resulted in exposition and protrusion of the spinal cord and the meninges. Plain radiographs of the ventral-dorsal of the vertebrate column revealed a defect in the fusion of the dorsal spinous processes of the distal thoracic vertebrates (T6 – T13); while the right-lateral view revealed xyphosis of the entire lumbar region of the spine

VEGF Expression, Cellular Infiltration, and Intratumoral Collagen Levels after Electroporation-Based Treatment of Dogs with Cutaneous Squamous Cell Carcinoma

Canine cutaneous squamous cell carcinoma (SCC) is the most common type of skin cancer in tropical countries and is generally associated with exposure to solar ultraviolet light. It has a low metastatic rate, and local treatments, such as electrochemotherapy (ECT), promote long-term control or even complete remission. This study aimed to evaluate pre- and post-ECT treatment expression levels of vascular endothelial growth factor (VEGF) and CD31, cellular infiltration, and intratumoral collagen levels in dogs with cutaneous SCC. A prospective nonrandomized clinical study was performed using dogs with spontaneous SCC treated with ECT. Eighteen lesions from 11 dogs were included in the study. The expression levels of VEGF and CD31; cellular infiltration; and intratumoral collagen levels, as determined by Masson’s trichrome staining, were not significantly different from pre-treatment measurements on day 21 (p > 0.05). However, among cellular infiltration, the mixed subtype was correlated with better overall survival time when compared to lymphoplasmacytic and neutrophilic infiltration (p < 0.05). In conclusion, ECT had no effect on VEGF expression, cellular infiltration, or intratumoral collagen levels in dogs with cutaneous SCC at the time of evaluation, suggesting that early and late post-ECT-treatment phases should be considered

Evaluation of cortisol and glycemia levels of dogs anesthetized with sevoflurane and premedicated with either butorphanol or phetidine

O objetivo deste estudo foi comparar a influência do butorfanol ou meperidina como medicação préanestesica nos níveis de cortisol e glicemia em vinte cães submetidos a cirurgia ortopédica experimental. Os cães foram distribuídos em grupos: GI recebeu acepromazina e butorfanol (0,05 mg.kg 1 e 0,4 mg.kg 1 respectivamente, i.m.) e GII, acepromazina e meperidina (0,05 mg.kg 1 e 4 mg.kg 1 respectivamente, i.m.). A indução anestésica constou de propofol (5 mg.kg 1) e para a manutenção sevofluorano em 100% de oxigênio. A concentração plasmátca de cortisol e glicose foram mensuradas no momentos: T0 antes da medicação pré-anestésica; T1 – vinte minutos após a medicação pré-anestésica; T2 – incisão de pele; T3 – estimulação periosteal e T4 – sutura de pele. Não houve diferença entre os momentos e grupos na dosagem de glicose. A concentração plasmatica de cortisol foi significativamente maior nos cães que receberam butorfanol entre T0 e T3, comparado com o grupo que recebeu meperidina. Esses resultados sugerem que a meperidina promove maior controle da dosagem de cortisol em cães submetidos a cirurgia ortopédica e anestesiados com sevofluorano.The objective of this study was to compare the influence of butorphanol and phetidine as part of the preanesthetic medication, in 20 healthy dogs submitted to experimental orthopedic surgery. Dogs were randomly allocated in two groups: GI, acepromazine and butorphanol (0,05 mg.kg 1 and 0,4 mg.kg 1, respectively, i.m.) and, GII, acepromazine and phetidine (0,05 mg.kg 1and 4 mg.kg 1, respectively, i.m.). Anesthesia was induced by administration of propofol (5 mg.kg 1) and maintained by the use of sevoflurane delivered in a 100% oxygen circuit. Plasma concentrations of cortisol and glucose were measured during several surgical procedures: T0, before preanesthetic medication; T1, 20 minutes after preanesthetic medication; T2, at skin incision; T3, at periostal stimulation; and, T4, at skin suture. Concentrations of plasma glucose were not significantly different between the surgical procedures and between the two groups evaluated. Concentrations of plasma cortisol were significantly higher in dogs administered with butorphanol between the surgical procedures of T0 and T3, compared with values for dogs administered with phetidine. These results suggest that phetidine is more adequate to control plasma cortisol in dogs submitted to orthopedic surgery than anesthesia with sevoflurane

Intraocular pressure and Schirmer tear test values in maned wolf (Chrysocyon brachyurus)

Abstract: The purpose of this study was to establish baseline data on lacrimal quantity (STT-1) and intraocular pressure (IOP) in captive maned wolves. Ten healthy adult maned wolves were contained with a snare pole and muzzle and kept in decubitus of the left side. STT-1 measurement was performed on the lateral third of the lower conjunctival sac for one minute. The cornea was desensitized and intraocular pressure was measured with an tonopen. Average STT-1 in both eyes was 11±5mm.min-1, with no statistical difference between the left and right eye (p=0.960). Average IOP in both eyes was 20±6mmHg, with no statistical difference between the left and right eye (p=0.836). Average STT-1 was lower than, and IOP was the same as normal levels found in dogs. There was no statistical difference in the age of the animals, and STT-1 and IOP values. In the present paper, average maned wolf STT-1 levels were lower compared with those found in dogs, while the IOP was the same in maned wolves as in dogs. Due to the increased incidence in providing emergency care for maned wolf victims of road kill and fires, determination reference values of ocular parameters may improve the correct diagnosis and treatment of the disease

Hepatic function evolution in dogs anesthetized with Zolazepam/Tiletamine

Foram avaliados os efeitos da associação zolazepam/tiletamina sobre o fígado por meio da alterações nas concentrações séricas de enzimas hepáticas. Foram utilizados dez cães clinicamente hígidos, distribuídos em dois grupos de cinco animais designados como grupo I (GI) e grupo II (GII). Os animais de GI foram submetidos a 6,6 mg/kg de zolazepam/tiletamina, por via intramuscular em dose única. No GII, aplicouse 6,6 mg/kg de zopazepam/tiletamina pela mesma via; decorridos 40 e 80 minutos, os animais receberam outras duas aplicações de 3,3 mg/kg por via intravenosa. As provas de função hepática foram realizadas por meio das dosagens de alanina amino transferase (ALT), aspartato amino transferase (AST), fosfatase alcalina (FA) e gama glutamil transferase (GGT). As amostras foram obtidas nos momentos M0 até M4, sendo: M0 anterior a aplicação da medicação; M1 até M3 com intervalos de 20 minutos após M1; e M4 24 horas após M1. Os dados foram submetidos ao teste de normalidade de Kolmogorov-Smirnov, e o teste de Tukey foi utilizado na comparação das médias das variáveis. O nível de significância estabelecido foi de 5%. Os valores médios de todas as enzimas avaliadas permaneceram dentro da normalidade em ambos os grupos, não apresentando variações dignas de nota nem estatisticamente significativas entre momentos bem como entre grupos. Diante dos resultados obtidos nesse experimento, conclui-se que: a associação anestésica zolazepam/tiletamina na dose de 6,6 mg/kg, seguida de duas novas aplicações de 3,3 mg/kg elevam as enzimas hepáticas avaliadas em cães, sem ultrapassar os valores fisiológicos; uma dose de 6,6 mg/kg de zolazepam/tiletamina por via intramuscular promove valores menores das enzimas avaliadas em relação a três doses.The hepatic effects of the anesthetic association zolazepam/tiletamine were investigated in dogs by analyzing the serum concentration of hepatic enzymes. Ten healthy dogs were divided into two groups of five, group I (GI) and group II (GII). The animals of GI received a single dose of 6,6 mg/kg of zolazepam/tiletamine, by intramuscular (IM) injection. GII dogs received 6,6 mg/kg of zolazepam/ tiletamine by the IM route; after a period of 50 – 80 minutes the animals received two additional doses (3,3 mg/kg) by intravenous administration[SAH1]. The hepatic function were analyzed by monitoring the serum concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), and gamma-glutamyl-transferase (GGT). Four blood samples were collected in different moments during the analyses: M0, before the first application of the drug; and M1 to M4. M1 through M3 was collected with intervals of 20 minutes before M0, while M4 was obtained 24 hours after M1. The normality of the obtained results was analyzed by Kolmogorov-Smirnov Test; while the Tukey’s test compared the means, using a level of significance of 5% for both statistical analyses. The mean values of all enzymes evaluated were within normal limits for both experimental groups, without any significant statistical alteration being observed between and within these groups. These results demonstrated that the association of zolazepam/tiletamine at the dosage of 6.6 mg/kg, followed by two applications additional of 3.3 mg/kg resulted in elevation of the evaluated hepatic enzymes without exceeding the physiologic values. Additionally, a single application of 6.6 mg/kg of zolazepam/ tiletamine by the intramuscular route resulted in lower values when compared to three applications