PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Safatle A.M.V., Hvenegaard A.P., Otsuki D., Martins T.L., Kahvegian M., Berezovsky A., Salomão S.R. & Barros P.S.M. 2010. Comparison of full-field electroretinogram in diabetic and non diabetic dogs with cataracts. Pesquisa Veterinária Brasileira 30(12):1071-1076. Laboratory of Investigation in Comparative Ophthalmology, Veterinary Teaching Hospital, School of Veterinary Medicine, University of São Paulo, Av. Prof. Dr. Orlando de Marques de Paiva 87, Bloco 8 superior, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: angsaf@usp.br Being the commonest ocular disorder, dense cataracts disable fundoscopic examination and the diagnosis of retinal disorders, which dogs may be predisposed. The aim of this study was to compare the electroretinographic responses recorded according to the International Society for Clinical Electrophysiology of Vision human protocol to evaluate retinal function of diabetic and non diabetic dogs, both presenting mature or hypermature cataracts. Full-field electroretinogram was recorded from 66 dogs, with ages varying from 6 to 15 years old allocated into two groups: (1) CG, non diabetic cataractous dogs, and (2) DG, diabetic cataractous dogs. Mean peak-to-peak amplitude (microvolts) and b-wave implicit time (milliseconds) were determined for each of the five standard full-field ERG responses (rod response, maximal response, oscillatory potentials, single-flash cone response and 30 Hz flicker). Comparing CG to DG, ERGs recorded from diabetic dogs presented lower amplitude and prolonged b-wave implicit time in all ERG responses. Prolonged b-wave implicit time was statistically significant (p< 0.05) at 30 Hz flicker (24.0 ms versus 22.4 ms). These data suggests full-field ERG is capable to record sensible alterations, such as flicker’s implicit time, being useful to investigate retinal dysfunction in diabetic dogs.

• Cataracts diabetes mellitus diabetic retinopathy retina catarata retinopatia diabética

Abstract in Portuguese:

RESUMO.- Safatle A.M.V., Hvenegaard A.P., Otsuki D., Martins T.L., Kahvegian M., Berezovsky A., Salomão S.R. & Barros P.S.M. 2010. Comparison of full-field electroretinogram in diabetic and non diabetic dogs with cataracts. [Estudo comparativo do eletrorretinograma de campo total em cães diabéticos e não diabéticos com catarata.] Pesquisa Veterinária Brasileira 30(12):1071-1076. Laboratory of Investigation in Comparative Ophthalmology, Veterinary Teaching Hospital, School of Veterinary Medicine, University of São Paulo, Av. Prof. Dr. Orlando de Marques de Paiva 87, Bloco 8 superior, Cidade Universitária, São Paulo, SP 05508-270, Brazil. E-mail: angsaf@usp.br Catarata madura e hipermadura, alteração frequentemente observada em cães, impossibilita a visibilização do fundo do olho e provável diagnóstico de degenerações retinianas. Objetivou-se comparar as respostas retiniana de cães diabéticos e não diabéticos, ambos portadores de catarata madura ou hipermadura, com auxílio do eletrorretinograma de campo total, utilizando o protocolo da International Society for Clinical Electrophysiology of Vision. Sessenta e seis cães, com idades variando entre 6 a 15 anos de idade foram divididos em dois grupos: (1) CG, cães não diabéticos com catarata madura ou hipermadura e (2) DG, cães diabéticos com catarata madura ou hipermadura. Mensurou-se amplitude pico a pico (microvolts) e tempo de culminação da onda-b (milisegundos) para as cinco respostas do ERG (resposta de bastonetes, máxima resposta, potencial oscilatório, resposta de cones e flicker a 30Hz). Avaliando-se as respostas obtidas com o exame, o grupo de cães diabéticos apresentou menor amplitude e maior tempo de culminação da onda-b em todas as respostas. O aumento do tempo de culminação da onda-b em DG foi estatisticamente significante (p<0.05) no flicker a 30 Hz (24.0ms versus 22.4ms). ERG de campo total é capaz de registrar alterações em respostas sensíveis como o tempo de culminação da onda-b do flicker, podendo ser útil para investigar retinopatias em cães diabéticos.

Abstract in English:

ABSTRACT.- Safatle A.M.V., Hvenegaard A.P., Kahvegian M., Martins T.L., Shimamura G.M., Fantoni D.T. & Barros P.S.M. 2010. [Full field electrorretinogram standartization in dogs.] Padronização do eletrorretinograma de campo total em cães. Pesquisa Veterinária Brasileira 30(9):763-769. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, 05508-270 São Paulo, SP, Brazil. E-mail: angsaf@usp.br Electroretinogram (ERG) is an objective non invasive diagnostic method to evaluate retinal function which permits the early detection of lesions at retinal external layers, even before the appearance of clinical signs. In dogs, ERG is mostly utilized for preoperative evaluation in patients presenting cataracts; characterization of disturbances causing blindness, among the utilization of dogs as animal models in scientific research. Several factors interfere in ERG responses, such as the ERG machine, light stimulation, electrode, time spent on dark adaptation, pupil size, means opacity, sedation or anesthetization, species, breed and age. The purpose of this study was to standardize the full field ERG in sedated dogs, according to the International Society for Clinical Electrophysiology of Vision (ISCEV) protocol, using Ganzfeld and bipolar electrodes. Two hundred thirty threes ERGs were performed in 147 female and 86 male with ages from 1 to 14 years old. Among those 233 dogs, 100 presented cataracts in different stages of maturation, 72 were diabetic and presented mature or hypermature cataracts, 26 presented ERG compatible to progressive retinal degeneration, 3 presented ERG compatible to sudden acquired retinal degeneration syndrome; for 32 dogs no abnormal ERG was registered and they were considered as having normal retinal function. Sedation was capable to induce a good immobilization with no bulb rotation, resulting uniform retinal stimulation, using Ganzfeld. Veris system successfully registered all 5 ISCEV responses, simultaneously from both eyes, at the same time. Full field ERG became a fundamental ophthalmic exam, then, its standardization is mandatory to allow comparison between ERGs from different laboratories. The reliability and reproducibility of this protocol has shown very good responses, using ISCEV protocol, Veris system, Ganzfeld and Burian Allen electrodes in sedated dogs.

• Retina electroretinogram eletrorretinograma

Abstract in Portuguese:

RESUMO.- Safatle A.M.V., Hvenegaard A.P., Kahvegian M., Martins T.L., Shimamura G.M., Fantoni D.T. & Barros P.S.M. 2010. [Full field electrorretinogram standartization in dogs.] Padronização do eletrorretinograma de campo total em cães. Pesquisa Veterinária Brasileira 30(9):763-769. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, 05508-270 São Paulo, SP, Brazil. E-mail: angsaf@usp.br Eletrorretinograma (ERG) é o meio diagnóstico objetivo e não-invasivo para avaliar a função retiniana e detectar precocemente, em várias espécies, lesões nas suas camadas mais externas. As indicações mais comuns para ERG em cães são: avaliação pré-cirúrgica de pacientes com catarata, caracterização de distúrbios que causam cegueira, além de servir como importante modelo para o estudo da distrofia retiniana que acomete o homem. Vários são os fatores que podem alterar o ERG tais como: eletrorretinógrafo, fonte de estimulação luminosa, tipo do eletrodo, tempo de adaptação ao escuro, tamanho pupilar, opacidade de meios e protocolo de sedação ou anestesia; além da espécie, raça e idade. Objetivou-se com este estudo padronizar o ERG para cães submetidos à sedação, seguindo o protocolo da International Society for Clinical Electrophysiology of Vision (ISCEV), utilizando Ganzfeld e eletrodos Burian Allen. Foram realizados 233 eletrorretinogramas em cães, 147 fêmeas e 86 machos, com idades entre um e 14 anos. Dos 233 cães examinados, 100 apresentavam catarata em diferentes estágios de maturação, 72 eram diabéticos e apresentavam catarata madura ou hipermadura, 26 apresentaram eletrorretinograma compatível com degeneração retiniana progressiva, três apresentaram eletrorretinograma compatível com síndrome da degeneração retiniana adquirida subitamente e 32 não apresentaram lesão retiniana capaz de atenuar as respostas do ERG, sendo considerados normais quanto à função retiniana. A sedação foi capaz de produzir boa imobilização do paciente sem rotacionar o bulbo ocular, permitindo adequada estimulação retiniana bilateralmente, com auxílio do Ganzfeld. O sistema eletrodiagnóstico Veris registrou com sucesso e simultaneamente de ambos os olhos, as cinco respostas preconizadas pela ISCEV. Como o ERG de campo total tornou-se exame fundamental na rotina oftalmológica, sua padronização é indispensável quando se objetiva comparar resultados de laboratórios distintos. A confiabilidade e reprodutibilidade deste protocolo foi demonstrada com a obtenção de registros de ótima qualidade utilizando protocolo padrão da ISCEV, eletrorretinógrafo Veris, Ganzfeld e eletrodos Burian Allen nos cães submetidos à sedação.

Abstract in English:

ABSTRACT.- Andrade J.N.B.M., Stopiglia A.J., Fantoni D.T., Abduch M.A. & Kahvegian M. 2009. Outflow occlusion for circulatory arrest in dogs. Pesquisa Veterinária Brasileira 29(2):137-142. Hospital Veterinário, Universidade de Franca, Av. Dr. Armando Salles Oliveira 201, Franca, SP 14404-600, Brazil. E-mail: jamescardio@terra.com.br The purpose of this study was to evaluate the possibility of producing circulatory arrest by occlusion of the pulmonary trunk as an alternative to the venous inflow occlusion through the left hemithorax. Eight healthy mongrel dogs were divided in two groups. Group I underwent 4 minutes of outflow occlusion and Group II was submitted to 8 minutes of circulatory arrest. Outflow occlusion was performed through left thoracotomy and pericardiotomy by passing a Rumel tourniquet around the pulmonary trunk. Physical examination, electrocardiography, echocardiography, blood gas analyses, hemodynamic, and oxygen transport variables were obtained before and after the procedure. The dogs from Group I did not have any clinical, electrocardiographic, echocardiographic, or hemo-dynamic abnormalities after anesthetic recover. In the Group II, only one dog survived, which had no clinical, electrocardiographic, or echocardiographic abnormalities. In this last dog, just after releasing the occlusion, it was detected increases in the following parameters: heart rate (HR), systolic, diastolic and mean arterial blood pressure (SAP; DAP; MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), central venous pressure (CVP), cardiac output (CO), systolic index (SI), cardiac index (CI), left and right ventricular stroke work (LVSW; RVSW), oxygen delivery index (DO2), oxygen consumption index (VO2), and oxygen extraction (O2 ext). Moreover, the oxygen content of arterial and mixed venous blood (CaO2; CvO2), and the arterial and mixed venous partial pressure of oxygen (PaO2; PvO2) were decreased 5 minutes after circulatory arrest. Outflow occlusion is a feasible surgical procedure for period of 4 minutes of circulatory arrest.

• Outflow occlusion circulatory arrest dogs

Abstract in Portuguese:

ABSTRACT.- Andrade J.N.B.M., Stopiglia A.J., Fantoni D.T., Abduch M.A. & Kahvegian M. 2009. Outflow occlusion for circulatory arrest in dogs. Pesquisa Veterinária Brasileira 29(2):137-142. Hospital Veterinário, Universidade de Franca, Av. Dr. Armando Salles Oliveira 201, Franca, SP 14404-600, Brazil. E-mail: jamescardio@terra.com.br The purpose of this study was to evaluate the possibility of producing circulatory arrest by occlusion of the pulmonary trunk as an alternative to the venous inflow occlusion through the left hemithorax. Eight healthy mongrel dogs were divided in two groups. Group I underwent 4 minutes of outflow occlusion and Group II was submitted to 8 minutes of circulatory arrest. Outflow occlusion was performed through left thoracotomy and pericardiotomy by passing a Rumel tourniquet around the pulmonary trunk. Physical examination, electrocardiography, echocardiography, blood gas analyses, hemodynamic, and oxygen transport variables were obtained before and after the procedure. The dogs from Group I did not have any clinical, electrocardiographic, echocardiographic, or hemo-dynamic abnormalities after anesthetic recover. In the Group II, only one dog survived, which had no clinical, electrocardiographic, or echocardiographic abnormalities. In this last dog, just after releasing the occlusion, it was detected increases in the following parameters: heart rate (HR), systolic, diastolic and mean arterial blood pressure (SAP; DAP; MAP), pulmonary artery pressure (PAP), pulmonary wedge pressure (PWP), central venous pressure (CVP), cardiac output (CO), systolic index (SI), cardiac index (CI), left and right ventricular stroke work (LVSW; RVSW), oxygen delivery index (DO2), oxygen consumption index (VO2), and oxygen extraction (O2 ext). Moreover, the oxygen content of arterial and mixed venous blood (CaO2; CvO2), and the arterial and mixed venous partial pressure of oxygen (PaO2; PvO2) were decreased 5 minutes after circulatory arrest. Outflow occlusion is a feasible surgical procedure for period of 4 minutes of circulatory arrest.

Abstract in English:

ABSTRACT.- Simões E.A., Jatene F.B., Bernardo W.M., Stopiglia A.J., Monteiro R, Fantoni D.T., Abduch C.D., Yasbek K.V.B., Irino E.T., Unruh S.M., Kahvegian M. & Soares A.L.H. 2007. [Viability of the right pneumonectomy in dogs: a parametric, hemogasometric and radiological evaluation.] Viabilidade da pneumonectomia direita em cães: uma avaliação paramétrica, hemogasométrica e radiográfica. Pesquisa Veterinária Brasileira 27(11):447-454. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: edas@uol.com.br In dogs, the evidence of viability of the right pneumonectomy, as well as the study of complications resulting from surgical procedure, are very important regarding the few specific studies made on the pneumonectomy in this animal species. The objective of this project was to carry out an experimental study to evaluate the viability of the right pneumonectomy in dogs through parametric, hemogasometric and radiographic evaluation. Ten adult healthy mongrel dogs, males and females, weighing 13-32 kg, were used. The dogs were submitted to selective intubation and right thoracotomy at the 5th intercostal space, where the pneumonectomy was performed. A radiografic evaluation was made on days 7, 30 and 60 after the surgery, as well as parametric and hemogasometric evaluations were done (before anesthetic induction, 1 hour after extubation, 48 hours and on days 7, 30 and 60 after the surgical procedure), considered important to evaluate possible complications due to the anesthetic and surgical techniques, as well as complications resulting from these procedures. The results were analyzed statistically. Besides the parametric and hemogasometric alterations, all dogs showed compensation for the gaseous exchanges after removing 57% of the pulmonary volume. Regarding the radiographic evaluation, it could be observed that the expansion of the remaining lung caused heart and lung displacement into the right hemithorax. It can be concluded that the right pneumonectomy is completely feasible in dogs, allowing a parametric, hemogasometric and radiographic satisfactory evaluation in all the animals.

• Pneumonectomy lung surgery dogs

Abstract in Portuguese:

ABSTRACT.- Simões E.A., Jatene F.B., Bernardo W.M., Stopiglia A.J., Monteiro R, Fantoni D.T., Abduch C.D., Yasbek K.V.B., Irino E.T., Unruh S.M., Kahvegian M. & Soares A.L.H. 2007. [Viability of the right pneumonectomy in dogs: a parametric, hemogasometric and radiological evaluation.] Viabilidade da pneumonectomia direita em cães: uma avaliação paramétrica, hemogasométrica e radiográfica. Pesquisa Veterinária Brasileira 27(11):447-454. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Orlando Marques de Paiva 87, São Paulo, SP 05508-900, Brazil. E-mail: edas@uol.com.br In dogs, the evidence of viability of the right pneumonectomy, as well as the study of complications resulting from surgical procedure, are very important regarding the few specific studies made on the pneumonectomy in this animal species. The objective of this project was to carry out an experimental study to evaluate the viability of the right pneumonectomy in dogs through parametric, hemogasometric and radiographic evaluation. Ten adult healthy mongrel dogs, males and females, weighing 13-32 kg, were used. The dogs were submitted to selective intubation and right thoracotomy at the 5th intercostal space, where the pneumonectomy was performed. A radiografic evaluation was made on days 7, 30 and 60 after the surgery, as well as parametric and hemogasometric evaluations were done (before anesthetic induction, 1 hour after extubation, 48 hours and on days 7, 30 and 60 after the surgical procedure), considered important to evaluate possible complications due to the anesthetic and surgical techniques, as well as complications resulting from these procedures. The results were analyzed statistically. Besides the parametric and hemogasometric alterations, all dogs showed compensation for the gaseous exchanges after removing 57% of the pulmonary volume. Regarding the radiographic evaluation, it could be observed that the expansion of the remaining lung caused heart and lung displacement into the right hemithorax. It can be concluded that the right pneumonectomy is completely feasible in dogs, allowing a parametric, hemogasometric and radiographic satisfactory evaluation in all the animals.