Comparação de enxerto ósseo cortical autógeno e implante ósseo cortical alógeno liofilizado, congelado a -70ºC ou conservado no mel na substituição de segmento diafisário do fêmur de gatos domésticos

Os felinos domésticos há muito tempo são utilizados como animais de companhia, tornando frequentes os atendimentos veterinários a esta espécie. As afecções ortopédicas em gatos ocupam papel de destaque na rotina do traumatologista veterinário, que pode deparar-se com fraturas cominutivas de ossos longos, neoplasias ósseas, não uniões ou uniões-viciosas de fraturas. Uma das opções para o tratamento dessas afecções é a utilização de enxerto ou implante ósseo. O objetivo deste trabalho foi avaliar implantes ósseos corticais alógenos conservados em mel, congelados a -70°C ou liofilizados na substituição de segmento diafisário do fêmur de felinos domésticos. Foi confeccionada uma falha óssea de três centímetros na região diáfisária do fêmur de 24 felinos adultos. Em seis felinos (grupo controle), a falha foi preenchida com o próprio osso removido após a retirada do periósteo, endósteo e medula óssea, e, em outros 18 animais, foi preenchida com implantes ósseos corticais alógenos conservados em mel (seis animais), congelado (seis animais) e liofilizado (seis animais). Os animais foram avaliados clínica, radiográfica e histologicamente, até completarem 180 dias de pós-operatório. A porcentagem de incorporação foi de 91,6% no grupo controle, com tempo médio necessário para consolidação de 83,1 dias; no grupo mel, foi de 75%, com tempo médio de 105 dias; no grupo congelado, foi de 83,3%, com tempo médio de 78 dias, e no grupo liofilizado foi de 25%, com tempo médio de 120 dias. Foi encontrada diferença estatisticamente significativa entre as porcentagens de consolidação do grupo liofilizado em relação aos grupos congelado e controle. Não houve diferença estatística entre os grupos com relação ao tempo de consolidação. Foi identificada a bactéria Brevibacterium spp. em um dos implantes conservados no mel. Foi possível concluir que os implantes ósseos autógenos e os conservados no mel e a -70°C foram eficazes no preenchimento de defeito cortical em fêmur de felinos adultos, enquanto que os implantes liofilizados necessitam de maior avaliação da resistência e imunogenicidade para tornarem-se uma opção viável em felinos

ANTIBIOTICOTERAPIA NO TRATAMENTO DE INFECÇÕES BACTERIANAS DO SISTEMA NERVOSO CENTRAL DE PEQUENOS ANIMAIS

Although infections in the central nervous system are less common than infections in other organics systems, they can cause life-threatening consequences and are a challenge for small animal practitioners. Among the factors that make these infections difficult to treat are the fact that it is surrounded by the blood-brain barrier, that hinders penetration of many substances, and the difficulty of obtaining positive results when trying to isolate the causative agent through spinal tap. This article aims to describe the blood-brain barrier, the most common antimicrobials used to treat bacterial infections in the central nervous system and their main applications in small animal practice. In the veterinary literature, trimethoprim, sulfonamides, chloramphenicol, and metronidazole are cited as antimicrobials with excellent penetration on the blood-brain barrier; oxacillin, penicillin’s, ceftriaxone, moxalactam, tetracyclines and carbenicillin with intermediate penetration; and aminoglycosides, first-generation cephalosporins, and clindamycin with little penetration. It was concluded that knowing the blood-brain barrier characteristics, pharmacokinetics and pharmacodynamics of antimicrobial agents, along with the main etiological agents, are the key to choose the most appropriate antibiotic to be applied in each individual case. It is noticed that in the veterinary literature there are few reports describing aspects of pharmacokinetics and pharmacodynamics in feline and canine species, requiring more studies in this area.Infecções no sistema nervoso central (SNC) são menos prevalentes do que em outros órgãos e o tratamento é desafiador. Entre os fatores que tornam o tratamento de infecções bacterianas complicado nesse tecido, destacam-se o fato do mesmo ser envolto pela barreira hematoencefálica, além da dificuldade de obter resultados positivos ao tentar isolar o agente causador por meio de punção de líquido cefalorraquidiano (LCR). Objetiva-se, nesse trabalho, documentar documentar os principais antibióticos utilizados para tratar infecções bacterianas no sistema nervoso central e a interação com a barreira hematoencefálica (BHE). Os antibióticos com ótima penetração na BHE são: trimetoprim, sulfonamidas, metronidazol e cloranfenicol com penetração penetração intermediária são: oxacilinas, penicilinas, ceftriaxone, moxalactam, tetraciclinas e carbenicilina; e com pequena penetração são: aminoglicosídeos, cefalosporinas de primeira geração e clindamicina. É fundamental para a escolha do antibiótico mais adequado para cada caso conhecer características da barreira hematoencefálica, além de determinar a farmacocinética e farmacodinâmica dos antibióticos e seus principais agentes etiológicos. Percebe-se que na literatura veterinária há escassos relatos descrevendo aspectos de farmacocinética e farmacodinâmica nas espécies felina e canina, sendo necessária maior maior quantidade de estudos nesta área

Retrospective Study of Anesthesias in Dogs and Cats Underwent to Neurosurgery

Background: The goal of anesthesia in patients with neurological diseases is to maintain the homeostasis of the central nervous system, focusing on intracranial pressure and pain during the intraoperative period. The purpose of this study was to evaluate the anesthesia performed between January 2010 and January 2016 at the Veterinary Clinical Hospital at the Federal University of Rio Grande do Sul and correlate the types of surgeries, drugs used in the pre-anesthetic medication, induction, pain control, and the development of complications during the procedure.Materials, Methods & Results: The medical records of 242 patients, who presented with neurological signs of spinal cord compression or traumatic brain injury, were assessed. Only 70 patients who underwent surgery had properly documented and detailed anesthesia records. Of these 70, there were 32 male and 38 female animals, with one feline and 69 canines. Their weights on the day of surgery ranged between 1.5 kg and 38 kg and their ages ranged from six months up to 13 years. We evaluated 74 surgeries because four patients underwent two separate surgeries. There were 38 hemilaminectomies, 14 ventral slots, seven vertebral stabilizations (one atlantoaxial instability and six vertebral fractures), six dorsal laminectomies, four pediculectomies, two fenestrations with hemilaminectomy, one durotomy with hemilaminectomy, one minihemilaminectomy, and one tumor removal. The complications observed were bradycardia (25/74), systemic hypotension (49/74), systemic hypertension, (21/74) and death (4/74). There was a great variation in the pre-anesthetic medication; either combinations of two or more drugs, one drug, or no medication was used. The most common drug used for induction of the patient was propofol, which was used in 46 cases as single agent and in 26 cases in combination with other drugs. In 43 patients, the majority of nociception control during the intraoperative period was achieved with continuous infusions of fentanyl combined with lidocaine, while some used ketamine. Pain control for the remaining 15 patients was accomplished with drug boluses. In two cases, the choice of opioid in the pre-anesthetic medication was repeated. Fourteen patients had remained without analgesia during surgery. No correlation was observed between the frequency of complications and the type of surgery performed, the medications used for induction of the patient, or the method of control of nociceptive stimuli during surgery. Continuous infusions were used frequently for pain control during surgery, however no significant correlation with complications was observed.Discussion: The high prevalence of neurological diseases that affect the spinal cord makes spinal surgery one of the most frequent neurosurgeries. The risk of complications in spinal surgery is affected by hemodynamics of the patient and may lead to death during the procedure. The most frequent complications are bradycardia, hypotension, cardiac electrophysiological changes, apnea, hemorrhage, and death. The survey identified bradycardia, hypotension, hypertension, and death as the major complications. The most frequent method of intraoperative analgesia was a continuous infusion, due to its benefits when compared to other methods of analgesia. When compared to previous studies, the present study showed similar complications that had no correlation wtih the type of surgery or anesthesia protocol

Mechanical study in vitro of the resistance of axial forces of 3.5 mm cannulated and conventional screws in head and femoral neck fractures

Background: Proximal femoral fractures account for 25% of all femoral fractures in dogs and are more common in young animals. Osteosynthesis of femoral head and neck fractures is a complex procedure that can be performed using conventional screws or wires. However, proper fracture reduction and fi xation are diffi cult to achieve and, despite many advancements, such fractures remain challenging to solve. Cannulated screws have good compressive capacity and can be employed to simplify the surgical procedure while optimizing outcomes. This study was designed to compare the resistance of conventional and cannulated screws to axial loading following experimental femoral neck fracture in dogs. Materials, Methods & Results: Fourteen cadaveric canine femurs were used in this study. Femurs were collected from dogs over 20 pounds in body weight with no gross or radiographic signs of orthopedic disease. Cadaveric femurs were submitted to experimental femoral neck fracture using a Gigli saw and allocated to osteosynthesis using either conventional or cannulated screws (seven bones each). All screws were inserted below the greater trochanter of the femur from the lateral aspect of the bone and screw topography confi rmed radiographically. Test specimens were then potted in polymethylmethacrylate, coupled to a hinged device and submitted to axial loading. Data on maximum load, maximum displacement, load within the proportional limit, offset within the proportional limit and load required to produce a 3 mm displacement were collected. Mean values were calculated and compared using the Student’s t test (P < 0.05). Mean values varied greatly within groups. Maximum load and displacement correspond to the critical point from which biomechanical testing becomes destructive. Data were missing from one test specimen (conventional screw group) due to abrupt diaphyseal fracture at the start of the axial loading trial. Discussion: The canine femur was selected as an experimentalmodel in this project due to the high incidence of femoral neck fractures in dogs. Also, studies on proximal femoral fracture osteosynthesis using cannulated screws are scarce. The effectiveness of the compression osteosynthesis technique employed in this trial has been confi rmed in several canine proximal femoral fracture studies, with reported success rates between 2 and 21%. Success rate variability could be due to substantial individual differences, as suggested by the large intragroup variation in this trial. The biomechanical behaviour of conventional sliding hip screws (SHC) and cannulated screws following experimental femoral neck fracture osteosynthesis was compared. Increased stiffness was achieved with SHCs, possibly due to more effi cient transmission of compressive forces to cortical bone under the plate. Compression screws act by transmitting compressive forces to cancellous bone under the fracture line. Replication of this scenario in this trial supports the recommendation that the lowest screw be inserted as close as possible to the medial cortex of the femur, which is stiffer than the cancellous bone in the femoral head. Under the conditions studied, mean maximum load values were higher when bone screws were inserted closer to the medial cortex of the femoral shaft and the proximal aspect of the femoral head, regardless of screw type. The opposite scenario was also observed (i.e. the farther from the medial cortex of the femoral shaft, the lower the mean maximum load). In this trial, conventional and cannulated screws were equally resistant to axial loading. However, femoral neck fracture osteosynthesis using cannulated screws was easier to perfor

Exérese de Schwanoma por meio da técnica de hemilaminectomia dorsolateral cervical cranial

Os tumores intradurais-extramedulares representam 50% das neoplasias do sistema nervoso. A maioria dos tumores intradurais-extramedulares caninos corresponde a neoplasias de raízes nervosas (neurofibromas, neurofibrossarcomas, schwanomas) e meningiomas. Optamos por descrever um caso de schwanoma uma vez que não o são rotineiramente relatados. Este trabalho refere-se a um cão da raça Pastor Belga, macho, 8 anos, atendido no Serviço de Neurologia do Hospital de Clínicas Veterinárias da Faculdade de Veterinária da Universidade Federal do Rio Grande do Sul com histórico de déficit de reação postural e hemiparesia dos membros torácico e pélvico do lado direito. O exame mielográfico evidenciou existência de massa subdural-extramedular no lado direito junto à articulação atlanto-occipital, compatível com neoplasia. O cão foi submetido a tratamento cirúrgico utilizando-se hemilaminectomia dorsolateral cervical cranial e remoção parcial do material compressivo. Setenta e cinco dias após a cirurgia o animal apresentou sinais de piora. O exame mielográfico evidenciou aumento de volume do tumor em relação ao inicial. Foi realizada exérese do tumor, porém, ao término do procedimento cirúrgico o paciente foi a óbito; essa situação condiz com a literatura, onde apenas uma pequena porcentagem desses tumores é completamente removida e as recidivas são altas

Nefrolitíase bilateral em cão : relato de caso

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Can the training regimen influence night time physical activity in racehorses?

Physical activity has been widely investigated in horses to elucidate locomotion characteristics and behavior. However, research in real environment of training stables is limited. The objective of this study was to evaluate the effect of training regimen on night time physical activity of racehorses. Physical activities of twenty animals were monitored during the night time using accelerometers. The animals were compared in terms of training regimen: horses subjected to training on continual days, and horses subjected to training on intermittent days; age and sex were also considered. The variables analyzed were: counts per minute, percentage of time in (sedentary, light, moderate and vigorous) physical activity. Statistical analysis was performed by the PROCGLM procedure (ANOVA) and the means were calculated by Tukey’s test. The training regimen impacts the physical activity of thoroughbreds. The mean counts per minute showed a higher physical activity in the intermittent trained animals in relation with continuously trained animals. The continuously trained animals presented a greater percentage of time in sedentary physical activity than those intermittent trained. However, intermittently trained horses spent a larger percentage of time in moderate and vigorous physical activity, in comparison with continuously trained animals. In conclusion, racehorses subject to training on continual days have lower physical activity in the night time than those that train on intermittent days

Fibrossarcoma em sítio de osteossíntese de fêmur com pino e placa em um felino

A 6-year old spayed female Siamese cat was presented with a history of left limb acute lameness. Radiographic imaging revealed a complete comminuted diaphyseal femur fracture, which was corrected through intramedullary pin placement along with plate osteosynthesis. After two months the animal returned to the hospital presenting severe diffuse enlargement of the left hindlimb, characterized as a non-delimited, solid, and firm plaque-like mass surrounding the pin and bone, which extended from the femorotibiopatelar joint to the pelvis, and infiltrated the adjacent musculature. Incisional biopsy exam indicated a highly malignant sarcoma. The entire limb was surgically removed and sent to histopathological evaluation. Microscopically, the mass was composed of spindle shaped cells, displaying high pleomorphism and cellular atypia. Abundant collagen production was evidenced through Masson’s trichrome stain and strong cytoplasmic staining for vimentin. These results were consistent with fibrosarcoma. The cat went through one session of chemotherapy; however, tumor recurrence occurred 20 days later, and the animal was submitted to euthanasia. This is the first description of fibrosarcoma arising in the vicinity of an intramedullary pin and plate in a cat.Uma gata, castrada, 6 anos de idade, da raça Siamês, apresentou histórico clínico de claudicação aguda do membro pélvico esquerdo. O exame radiográfico revelou uma fratura completa cominutiva diafisária do fêmur, a qual foi corrigida através de osteossíntese pela implantação de um pino intramedular, além de placa metálica. Depois de dois meses, o felino retornou ao hospital apresentando aumento severo e difuso do membro pélvico, caracterizada por uma massa não delimitada, sólida, como uma placa, circundando o pino e o osso, a qual se estendia da articulação femorotibiopatelar até a pelve, e infiltrava a musculatura adjacente. A biópsia incisional indicou sarcoma de alta malignidade. O membro inteiro foi cirurgicamente removido e enviado para análise histopatológica. Microscopicamente, a massa era composta por células fusiformes, demonstrando alto pleomorfismo e atipia celular. Abundante produção de colágeno foi evidenciada através da técnica histoquímica de tricrômico de Masson e forte imunomarcação citoplasmática para vimentina. Esses resultados foram consistentes com fibrossarcoma. O felino foi submetido a uma sessão de quimioterapia, porém houve recorrência tumoral 20 dias após a sessão, e o paciente foi submetido a eutanásia. Essa é a primeira descrição de fibrossarcoma que surgiu em local próximo a implantação de pino intramedular e placa em um felino

Prolapso uretral em um Bulldogue Inglês

O prolapso uretral é incomum em cães, e se caracteriza pela protusão da mucosa uretral além da extremidade do pênis. O presente relato descreve o caso de um cão, Bulldogue Inglês, 6 meses de idade, atendido no Hospital de Clínicas Veterinárias da Universidade Federal do Rio Grande do Sul (HCV-UFRGS) com histórico de sangramento prepucial. Ao exame físico, o animal apresentou aumento de volume da glande do pênis, de coloração avermelhada e presença de hemorragia local. Descartadas quaisquer outras patologias, confirmou-se o prolapso uretral. Encaminhado para cirurgia, realizou-se ressecção da porção uretral prolapsada e posterior sutura da mucosa uretral no epitélio peniano. Passados 15 dias do procedimento cirúrgico, o animal retornou para revisão onde foi evidenciada completa cicatrização uretral