High carbohydrate is preferable to high lipid parenteral nutrition in healthy dogs undergoing prolonged sedation.

Parenteral nutrition (PN) is commonly used in intensive care units (ICUs) and is associated with earlier hospital outcome. However, there is scarcity of information about the metabolic effects of PN caloric distribution for dogs. Considering the high tolerance of dogs to lipids and, also, that hospitalized animals usually present insulin resistance, PN formulation with high fat instead high glucose can provide metabolic benefits in this specie. This study evaluated two PN protocols, based on high lipid or high carbohydrate in 12 healthy dogs under sedation/ventilation during 24 h. For baseline data, blood samples were collected 24 h before the study beginning. After fasting, the dogs were anesthetized and put under mechanical ventilation without energy support for 12 h to obtain: daily energy expenditure (DEE), respiratory quotient (RQ), oxygen consumption (VO2), carbon dioxide production (VCO2), lactate, glucose, cholesterol, and triglycerides concentrations. After, the dogs were allocated into two groups: lipid-based energy group (LEG) and carbohydrate-based energy group (CEG). Both groups received the PN infusions at a rate of 3 mL/kg/h for 12 h. Blood tests were performed 12, 24, and 48 h after infusion's completion. VO2 increased after PN in LEG, increasing energy expenditure compared to CEG. RQ remained close to 1 in CEG, indicating carbohydrate preferential consumption. Triglycerides increased in both groups after propofol infusion, remaining higher in LEG until the end of the evaluation. Glycaemia increased in CEG compared to baseline. In conclusion, both PN protocols can be used in healthy animals undergoing prolonged sedation protocols. However, high lipid PN had higher VO2 and DEE, and resulted in higher triglycerides concentrations and lower glycaemia indexes than carbohydrate, making high carbohydrate PN preferable to high lipid PN. Therefore, for use in critically ill patients, the data obtained in this study should be extrapolated, taking into consideration the specificity of each case.

Acute exposure to isoflurane impairs sperm parameters in mice.

Isoflurane, an inhalational anesthetic from the halogenated group, has been increasingly used in the medical and scientific fields. Due to its characteristics, it is capable of inducing anesthesia quickly and quietly; however, the adverse effects resulting from its use have not yet been fully elucidated, especially with regard to reproductive aspects. Considering its common use in research laboratories, whether for performing surgical procedures or for prior exposure to euthanasia, knowledge about its interference in sperm parameters of experimental models characterizes an important study goal. The aim of the present study was to determine the interference of acute exposure to isoflurane on the sperm quality of mice, both immediately previous to euthanasia and in later evaluation, twenty days after a single anesthetic exposure. Our results demonstrate that acute anesthetic exposure reduces sperm motility and is responsible for the formation of damaged sperm cells that are prone to apoptosis, which may affect the outcome of reproductive experiments even 20 days after exposure.

Laparoscopic nephron-sparing surgery for the treatment of canine dioctophymosis.

This paper reports on two cases of laparoscopic nephrotomy employed in the treatment of canine dioctophymosis, which is considered a unusual procedure and a new treatment proposal heretofore not performed in veterinary medicine. Two patients were treated, one with a history of hematuria and the other with incidental finding of the parasite in the abdominal cavity during elective ovariohysterectomy. Both dogs were subjected to abdominal ultrasound, which produced images indicating the presence of the parasite in the right side kidney, but with partial parenchymal preservation. The patients were therefore subjected to laparoscopic nephrotomy. The surgical procedure was effective in treating dioctophymosis and enabled minimum tissue invasion during surgery, in addition to preservation of the kidney.

Electrocardiographic, echocardiographic, and indirect blood pressure evaluation in dogs subjected to different sedation protocols / Avaliação eletrocardiográfica, ecocardiográfica e de pressão arterial não invasiva de cães submetidos a diferentes protocolos de sedação

ABSTRACT: The present study aimed to evaluate the effects of different sedation protocols on blood pressure and echocardiographic and electrocardiographic parameters in dogs. In total, 24 male mixed-breed dogs with a mean weight of 9.87±3.0kg were used.Animals were randomly divided into four groups (n=6), which were subjected to sedation using the following protocols: acepromazine (0.05mgkg-1) and butorphanol (0.3mgkg-1) (AB); acepromazine (0.05mgkg-1)and methadone (0.5mgkg-1) (AM); acepromazine (0.03mgkg-1), methadone (0.5mgkg-1), and midazolam (0.3mgkg-1)(MAM); and methadone only (0.5mgkg-1) (M). Indirect blood pressure (BP) measurements and computerized electrocardiography (ECG) and echocardiography (ECO) were performed immediately before the application of the sedation protocol (baseline), and the same evaluations were repeated after 15 minutes. BP decreased in groups AB, MAM, and AM compared to baseline values. Electrocardiographic measurements showed decreased heart rates (HRs) after sedation in all groups, and bradycardia was observed after sedation in two dogs from group M and one animal from group AM. The P-wave duration increased after sedation in groups AM and M. After sedation, no changes in cardiac dimensions were revealed byECO.Fractional shortening (FS) decreased after sedation in the AM group, and dogs from group AB exhibited a smaller decrease in FS compared with the other groups. The cardiac index (CI) was lower in groups AM and M than in the other groups. Animals from group AB were less resistant to examination and exhibited the most favorable sedation scores. It was concluded that the combination of acepromazine and butorphanol was the best sedation protocol for performing echocardiogram measurementsbecause dogs were less resistant to examinations and echocardiographic parameters of FS and CI remained stable.

RESUMO: O objetivo deste estudo foi avaliar os efeitos de diferentes protocolos de sedação sobre a pressão arterial, parâmetros ecocardiográficos e eletrocardiográficos em cães. Foram utilizados 24 cães, machos, SRD, com peso médio de 9,87±3,0kg, os quais foram alocados aleatoriamente em quatro grupos (n=6), que foram submetidos à sedação com os protocolos acepromazina (0,05mgkg-1) e butorfanol (0,3mgkg-1) (AB), acepromazina (0,05mgkg-1) e metadona (0,5mgkg-1) (AM), acepromazina (0,03mgkg-1), metadona (0,5mgkg-1) e midazolam (0,3mgkg-1) (MAM) e metadona isolada (0,5mgkg-1) (M). Foi realizada avaliação da pressão arterial sistólica (PAS) não invasiva, eletrocardiografia computadorizada e ecocardiografia imediatamente antes da aplicação do protocolo de sedação (basal) e repetindo-se as mesmas avaliações, 15 minutos após. Observou-se redução na PAS nos grupos AB, MAM, AM, em relação ao basal. Na eletrocardiografia, houve redução da FC após sedação em todos grupos, sendo observada bradicardia após sedação em dois cães do grupo M e um animal do grupo AM. A duração da onda P aumentou após sedação nos grupos AM e M. Não foram observadas alterações nas dimensões cardíacas, avaliadas pela ecocardiografia, após sedação. A fração de encurtamento (FS) reduziu após sedação no AM e os cães do AB apresentaram menor queda da FS, diferindo dos demais grupos. O índice cardíaco (IC) foi menor no AM e M em relação aos demais. Os animais do grupo AB foram menos resistentes à execução dos exames, apresentando melhores escores de sedação. Concluiu-se que a associação acepromazina e butorfanol foi o melhor protocolo de sedação para realização do ecocardiograma, sendo os cães menos resistentes à execução do exame, mantendo estáveis os parâmetros ecocardiográficos de fração de encurtamento e índice cardíaco.

Cardiac index by thermodilution or transthoracic echocardiography in dogs at different hemodynamic states / Índice cardíaco pelos métodos de termodiluição ou ecocardiografia transtorácica em cães sob diferentes situações hemodinâmicas

ABSTRACT: Proper monitoring of cardiac index (CI) in critically ill patients requires accurate and minimally invasive methods. The aim of this study was to compare the CI values obtained by thermodilution or echocardiography using different methods in dogs in different hemodynamic states. Nine dogs weighing 19.6±1.3kg were anesthetized with isoflurane at 1.4V% (Baseline) and subjected to mechanical ventilation (MV),a hypodynamic state (Hypo) with isoflurane at 3.5V% and hyperdynamic state (hyper) with dobutamine infusion at 5μgkg-1min-1. CI analysis was performed by thermodilution (TD) and using the modified Simpson's method, aortic velocity-time integral (A-VTI) method and pulmonary VTI (P-VTI) method. We performed Pearson's correlation and Bland-Altman analysis. The CI values (Lm-2min-1) of the animals in the Baseline, MV, Hypo and Hyper states were 4.3±1, 3.6±0.7, 2.9±0.66 and 6.1±2, for TD; 2.8±0.7, 2.4±0.3, 1.7±0.7 and 4.4±1.2, for Simpson's method; 3.4±0.9, 3.1±0.7, 2.6±3.4, 6.1±1.8 for A-VTI; and 3.6±0.8, 3.6±0.8, 2.7±0.6 and 6.2±1.5, for P-VTI. The CI values using Simpson's method were lower than those obtained by TD in all states, and it was observed a significant correlation in the Hypo (r=0.89) and Hyper (r=0.76) groups. In addition,the percent error in the Hypo group using Simpson's method was 26% relative to TD, which allowed for the identification of the different hemodynamic states. With respect to the other methods and states, there was no agreement or correlation between the methods and TD. We concluded that none of the tested echocardiography methods exhibited acceptable agreement with thermodilution at different hemodynamic states.

RESUMO: A adequada monitoração do índice cardíaco (IC) em pacientes críticos requer métodos acurados e minimamente invasivos. O objetivo deste estudo foi comparar o IC obtido por termodiluição ou ecocardiografia em cães sob alterações hemodinâmicas. Utilizaram-se nove cães pesando 19,6±1,3kg, os quais foram anestesiados com isofluoranoa1,4V% (Basal) e submetidos à ventilação mecânica (VM) e estados hipodinâmico (Hipo) com isofluoranoa3,5V% e hiperdinâmico (Hiper), com dobutaminaa5µgkg-1min-1. O IC foi obtido por termodiluição (TD) e pelos métodos ecocardiográficos de Simpson modificado, e pela velocidade em tempo integral (VTI) nas valvas aórtica (VTI-A) e pulmonar (VTI-P). Realizou-se a análise de correlação de Pearson e de concordância de Bland-Altman. O IC (Lm-2min-1) nas fases Basal, VM, Hipo e Hiper foi de 4,3±1, 3,6±0,7, 2,9±0,66 e 6,1±2 para TD; 2,8 ±0,7, 2,4±0,3, 1,7±0,7 e 4,4±1,2 para Simpson; 3,4±0,9, 3,1 ±0,7, 2,6±3,4, 6,1±1,8 para VTI-A e 3,6±0,8, 3,6±0,8, 2,7±0,6 e 6,2±1,5 para VTI-P. O método de Simpson foi menor que a TD em todas as fases, mas com correlação significativa nos estados Hipo (r=0,89) e Hiper (r=0,76) e percentagem de erro de 26% no Hipo em relação à TD, identificando os diferentes estados hemodinâmicos. Nos demais, não houve concordância ou correlação com a TD. Conclui-se que nenhum dos métodos testados apresentou concordância aceitável com a termodiluição nos diferentes estados hemodinâmicos.

Indução anestésica com nanoemulsão ou emulsão lipídica de propofol durante dias consecutivos em gatas / Anesthetic induction with nanoemulsion or lipid emulsion of propofol during consecutive days in cats

O objetivo deste estudo foi comparar os efeitos clínicos da indução com propofol em nanoemulsão e em emulsão lipídica em gatas, após repetidas administrações. Utilizaram-se 12 gatas, hígidas, SRD, com peso médio de 2,9±0,6kg, distribuídas aleatoriamente em dois grupos: NANO (n=6) e EMU (n=6), que receberam propofol em nanoemulsão na dose de 9,5mg kg-1 e em emulsão lipídica na dose de 10mg kg-1, respectivamente, ambos pela via intravenosa, durante cinco dias consecutivos. Hemograma e função renal e hepática foram realizados a cada 24 horas e até 168 horas após a primeira indução. Os parâmetros clínicos de frequência cardíaca (FC) e respiratória (f) e temperatura retal (TR) foram avaliados antes dos tratamentos e 5, 10, 20 e 30 minutos após a administração de propofol. Em relação aos valores basais, observou-se diminuição da FC no EMU até o 3° dia e da f e TR em ambos os grupos até o último dia, sem diferença entre os dias. As enzimas ALT e FA diminuíram após 24 a 96 horas e 48 a 144 horas, respectivamente, no grupo EMU. Os valores de eritrograma diminuíram até o quinto dia em ambos os grupos. Os tempos para hipnose, extubação e para decúbito esternal não diferiram entre grupos e entre os dias. O tempo para recuperação total do grupo EMU foi maior no 4° e 5° dias em relação ao 1°. Conclui-se que a indução com propofol é segura e que o propofol em emulsão lipídica apresenta maior efeito cumulativo após repetidas administrações em gatas.

The aim this study was to compare the clinical effects of induction with propofol in lipid emulsion and nanoemulsion in cats after repeated administrations. Twelve healthy mongrel cats, with an average weight of 2.9±0.6kg, were randomly distributed into two groups: NANO (n=6) and EMU (n=6), who received propofol in nanoemulsion at dose of 9.5mg kg-1 and in lipid emulsion at a dose of 10mg kg-1, respectively, both intravenously for five consecutive days. Blood count and kidney and liver function were performed every 24 hours until 168 hours after the first induction. The clinical parameters of heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated before treatment and 5, 10, 20 and 30 minutes after administration of propofol. At baseline, there was a decrease in HR in the EMU until the 3rd day and RR and RT in both groups until the last day, with no difference between days. The enzymes ALT and ALP decreased after 24 to 96 hours and 48 to 144 hours, respectively in EMU group. The values of blood count decreased until the fifth day in both groups. The times of hypnosis, extubation and sternal recumbency did not differ between groups and between days. The total recovery time of EMU group was higher in the 4th and 5th day in relation to the 1st. Concludes that the induction with propofol is safe and that propofol in lipid emulsion has a higher cumulative effect after repeated administration in cats.

Farmacocinética do propofol em nanoemulsão em cães / Pharmacokinetics of propofol nanoemulsion in dogs

O propofol em nanoemulsão é uma nova formulação constituída por sistemas nanoemulsionados, caracterizado pela ausência do veículo lipídico. A modificação do veículo pode acarretar alterações farmacocinéticas, resultando em diferentes taxas de distribuição e excreção do propofol. O objetivo deste estudo foi avaliar a farmacocinética de uma nova formulação de propofol em nanoemulsão do tipo óleo em água, comparando com a formulação tradicional em emulsão lipídica. Foram utilizadas seis cadelas sem raça definida, castradas (10,7±1,5kg), em estudo aleatório e de autocontrole, que receberam as duas formulações de propofol com intervalo de 30 dias entre os tratamentos, sendo administrada uma dose bolus de 8mg kg-1, seguida de infusão contínua por 60 minutos na taxa de 0,4mg kg-1 min-1. Amostras de sangue arterial foram colhidas momentos antes da indução (0), 2, 5, 10, 15, 30 e 60 minutos após a dose bolus e após o término da infusão nos tempos 5, 10, 15, 30, 60 e 90 minutos e 2, 3, 4, 6, 10 e 24 horas. Não foram encontradas diferenças significativas entre os parâmetros farmacocinéticos de volume de distribuição, clearance, constante de eliminação, meia-vida e constantes de distribuição, demonstrando que o propofol em nanoemulsão não apresenta alteração farmacocinética em relação à formulação tradicional.

Propofol nanoemulsion is a new formulation consisting of nanoemulsified systems, characterized by the absence of lipid vehicle. Changes in drug vehicle may alter the pharmacokinetics and result in different distribution and elimination rates of propofol. The aim of this study was to evaluate the pharmacokinetics of a new oil in water propofol nanoemulsion formulation, compared to the traditional lipid emulsion. Six neutered female mixed-breed dogs were used (10.7±1.5kg) in a randomized and self control trial with 30 days interval. They received both propofol formulations administered as a bolus dose of 8mg kg-1 followed by 60 minutes continuous infusion at 0.4mg kg-1 min-1 rate. Arterial blood samples were collected just before induction (0), 2, 5, 10, 15, 30, and 60 minutes after the bolus dose, and after the end of the infusion at five, 10, 15, 30, 60, and 90 minutes and 2, 3, 4, 6, 10, and 24 hours. There were no significant differences in the evaluated pharmacokinetics parameters that included volume of distribution, clearance, elimination rate constant, half-life, and distribution constants, demonstrating that propofol nanoemulsion has no pharmacokinetics differences when compared to the traditional formulation.

Farmacocinética do propofol em nanoemulsão em gatos / Pharmacokinetic of propofol in nanoemulsion in cats

Os felinos são deficientes na biotransformação do propofol e os dados em relação à farmacocinética nessa espécie são escassos. O objetivo deste estudo foi determinar o perfil farmacocinético da infusão contínua de propofol em nanoemulsão juntamente com a emulsão lipídica em felinos. Utilizaram-se seis gatos sem raça definida (SRD), adultos, machos, castrados, com peso médio de 4,2±0,8kg, em estudo aleatório e de autocontrole. Os animais receberam 10mg kg-1 min-1 de propofol a 1% em emulsão lipídica (EMU) ou em nanoemulsão (NANO) durante 30 segundos e, imediatamente após, iniciou-se a infusão de 0,3 mg kg-1 min-1 da mesma formulação durante 60 minutos. Após 15 dias, receberam o mesmo tratamento com a formulação oposta. Amostras de 3mL de sangue venoso foram coletadas nos tempos 0 (basal), 2, 5, 10, 15, 30 e 60 minutos de infusão e aos 5, 10, 15, 30, 60, 90, 120, 180, 240, 360, 600 e 1440 minutos após o final da infusão. Os parâmetros farmacocinéticos foram determinados a partir da curva de decaimento da concentração plasmática versus tempo ao final da infusão. A análise estatística foi realizada através de ANOVA-RM com posterior teste t pareado entre os grupos. Não houve diferença entre as formulações em relação a todos os parâmetros. Os volumes de distribuição foram altos com Vdss de 23,23±12,30 litros kg-1 para a nanoemulsão e de 18,12±8,54 litros kg-1 para a emulsão lipídica. Os Cls foram baixos com um Cl central de 22,20±10,83mL kg-1 min-1 para a nanoemulsão e de 23,42±13,50mL kg-1 min-1 para emulsão lipídica. Conclui-se que a farmacocinética do propofol em gatos após infusão contínua caracteriza-se por uma ampla distribuição tecidual e uma lenta eliminação, com possível efeito cumulativo. A formulação em nanoemulsão apresenta características farmacocinéticas semelhantes às da emulsão lipídica.

Cats are deficient in the metabolism of propofol and the data on the pharmacokinetics in this species are scarce. The aim of this study was to determine the pharmacokinetic profile of continuous infusion of propofol in lipid emulsion and compare with the nanoemulsion formulation, in cats. Domestic cats, short hair, adults, male, castrated, weighting 4.2±0.8kg in a randomized and self control trial were used. The animals received 10mg kg-1 of 1% propofol in lipid emulsion or nanoemulsion for 30 seconds and immediately after that, a continuous rate infusion of 0.3mg kg-1 min-1 of the same formulation was administered for 60 minutes. After 15 days the cats received the same treatment with the opposite formulation. Samples of 3mL of venous blood were collected by a central venous catheter inserted in the jugular vein at 0 (baseline), 2, 5, 10, 15, 30, and 60 minutes of infusion and at 5, 10, 15, 30, 60, 90, 120, 180, 240, 360, 600 and 1440 minutes after the end of the infusion. The pharmacokinetic parameters were determined from the decay curve of plasma concentration versus time at the end of the infusion. Statistical analysis was performed using RM-ANOVA with subsequent paired t-test between groups. There was no difference between the formulations with respect to all parameters. The volumes of distribution were high with Vdss of 23.23±12.30 liters kg-1 for the nanoemulsion and 18.12±8.54 liters kg-1 for lipid emulsion. The Cls were low with a Cl central to 22.20±10.83mL kg-1 min-1 for the nanoemulsion and 23.42±13.50mL kg-1 min-1 for lipid emulsion. The conclusion is that the pharmacokinetics of propofol in cats after infusion is characterized by a broad tissue distribution and a slow elimination, with possible cumulative effect. The formulation nanoemulsion has pharmacokinetic properties similar to the lipid emulsion.