Abordagens subzigomática e infraorbitária para o bloqueio do nervo maxilar em cadáver de gatos

This study compared the accuracy of dye placement on the maxillary nerve by using the percutaneous subzigomatic (SBZ) and infraorbitary (IO) approaches in cats’ cadavers. A second aim was to compare the accuracy of dye placement on the maxillary nerve between different untrained anesthetists. This was a prospective, randomized, blinded study, performed in 40 heads obtained from feline cadavers. Three veterinarians (A, B and C) with no previous experience with the IO approach performed the experiments. The SBZ approach was randomly performed on one side of the head and the IO approach was performed in the contralateral side of the same head. For each approach, 0.2ml of 1% methylene blue dye was injected. Scores for length of nerve staining were as follows: 0 (failure), no staining; 1 (moderate), <6mm of nerve stained; and 2 (ideal), ≥6mm of nerve stained. Median scores (interquartile range) for the SBZ and IO approaches were 2.0 (0.3-2.0) and 1.0 (0.0-2.0), respectively. Scores for length of nerve staining were higher with the SBZ approach than the IO approach (P=0.016). Considering the scores for both the SBZ and IO approaches, there was a significant difference among the three veterinarians (P=0.002). Results of this study do not support the IO approach to perform a maxillary nerve block in cats. A greater accuracy of methylene blue dye placement was observed with the SBZ approach. A variable accuracy may exist between different veterinarians when performing a maxillary nerve block employing the SBZ and IO techniques in cats.O objetivo deste estudo foi comparar o acesso do nervo maxilar pela abordagem subzigomática (SBZ) com a abordagem pelo forame infraorbitário (IO) em peças anatômicas de gatos utilizando o corante azul de metileno. Um segundo objetivo foi comparar a acurácia na coloração do nervo maxilar com o azul de metileno entre diferentes anestesistas que não receberam treinamento prévio. Este estudo foi prospectivo, randomizado, cego, realizado em 40 peças anatômicas de cabeças de gatos. Três veterinários (A, B e C), sem experiência prévia da abordagem IO, realizaram o experimento. A abordagem SBZ foi aleatoriamente realizada em um dos lados da cabeça e a abordagem IO foi realizada no lado contralateral da mesma peça anatômica. Para cada abordagem, utilizou-se 0,2mL do corante azul de metileno 1%. Classificou-se o escore de coloração baseado no comprimento do nervo maxilar corado pelo azul de metileno conforme a escala: 0 (falha da técnica), sem coloração; 1 (moderado), <6mm de coloração do nervo maxilar; 2 (ideal), ≥6mm de coloração do nervo maxilar. As medianas (intervalo interquartil) para as abordagens SBZ e IO (dados de todos os veterinários juntos) foram respectivamente 2,0 (0,3-2,0) e 1,0 (0,0-2,0). A abordagem SBZ foi associada a um escore de coloração, significativamente, maior do que a abordagem IO (P=0,016). Considerando os escores de ambas abordagens (SBZ e IO), houve diferença significativa nos escores de coloração do nervo maxilar entre os três veterinários anestesistas (P=0,002). Os resultados deste estudo não sustentam a utilização da abordagem IO para a realização do bloqueio maxilar em gatos. Uma melhor acurácia na coloração do nervo maxilar com o azul de metileno foi observada com a abordagem SBZ. A acurácia da técnica pode variar quando as abordagens SBZ e IO são realizadas por veterinários diferentes, com o objetivo de se obter o bloqueio do nervo maxila

Anesthetic Management of an Orange-Spined-Hairy-Dwarf-Porcupine (Sphiggurus villosus) Undergoing Myelography

 Background: The orange-spined hairy dwarf porcupine (Sphiggurus villosus) is a mammal that belongs to the rodentia order. Accidents involving this porcupine and dogs have become usual in some cities of Brazil. Dog bites may eventually result in spinal injuries. When there is clinical evidence of spinal cord injury, a myelography under general anesthesia may be required to allow identification of the exact location of the injury. To the authors’ knowledge, there is only one case report about anesthesia in Sphiggurus villosus where dissociative anesthesia was employed. This paper describes one case report of inhalation anesthesia with isoflurane in a Sphiggurus villosus undergoing myelography.Case: A 1.6 kg orange-spined hairy dwarf porcupine, with a history of dog bite was referred to the Veterinary Hospital of the University. On clinical examination, the patient was in good physical condition, alert, with an approximately 1-cm injury near the 10th and 11th thoracic vertebrae. Nociception in pelvic limbs was present whereas proprioception was absent. Radiographic examinations were suggestive of vertebral dislocation and fracture between the 10th and 11th thoracic verte­brae. A myelography was then requested by the responsible veterinarian. The porcupine received intramuscular midazolam (0.5 mg/kg) in combination with meperidine (10 mg/kg) as premedication. Anesthesia was induced and maintained with isoflurane in 100% oxygen via a face mask connected to a non-rebreathing circuit. Monitored variables at 5-min intervals included: pulse rate (PR) and systolic arterial blood pressure (SAP) measured by a Doppler ultrasound with its probe positioned at the palmar metacarpal artery; pulse oximetry (SpO2) measured by a sensor positioned at the tarsus; rectal temperature; and respiratory rate (RR). During the myelography, the range of values for the above mentioned variables were: PR, 189-206 beats/min; SAP, 90-130 mmHg; SpO2, 94-96%; RR, 32-40 breaths/min; and rectal temperature decreased by 0.5oC. Anesthetic recovery was uneventful. Postoperative pain relief was achieved with intramuscular tramadol (5 mg/kg).Discussion: To the authors’ knowledge, this is the first case report of inhalation anesthesia in a Sphiggurus villosus speci­men. In a previous case report, other authors described anesthesia for myelography in a porcupine with IM tiletamine/ zolazepam (5 mg/kg). In the case reported here, dissociative anesthetics, such as tiletamine, were avoided because these agents may increase intracranial pressure, cerebral blood flow and cerebrospinal fluid pressure, which are undesirable in patients with spinal trauma. Although physiologic variables were considered to be stable during anesthesia with isoflurane in this report, these findings have to be interpreted carefully. First, normal range of values for physiologic variables has not been reported for porcupines. Second, accuracy of the measurement techniques used (e.g. noninvasive measurement of SAP) has not been validated. Under the conditions reported in this case report, premedication with meperidine and mid­azolam was effective to induce good muscle relaxation and allowed anesthetic induction with isoflurane via a face mask. This anesthetic protocol provided adequate conditions for performing the myelography in a porcupine and physiologic variables remained stable throughout the procedure.Keywords: rodents, anesthesia, spinal trauma

Ureterocolonic Anastomosis in a Dog with Transitional Cell Carcinoma in the Vesical Trigone

Background: Primary bladder tumors are rare in dogs, in spite of that, the transitional cell carcinoma (TCC) is the malignant tumor that most affects dogs. The TCC usually begins in the vesical trigone and extends into the bladder, and may cause partial or complete obstruction of the urinary flow. The treatment with cystectomy and urinary diversion in veterinary medicine is not usual probably because the partial cystectomy has low success and ureterocolonic anastomosis can cause pyelonephritis and/ or urinary incontinence. This paper describes the cystectomy surgery and ureterocolonic anastomosis in a dog with TCC in the bladder and bilateral hydronephrosis. Case: A 8-year-old, male, not castrated, Pitbull was referred to the Veterinary Clinic Hospital - UFRGS. The patient had progressive weight loss, low appetite, dysuria, and hematuria. Abdominal ultrasound showed bilaterally hydronephrosis, kidney pelvis and ureter dilatation. The mesogastric region presented a mass measuring about 14 cm. An exploratory laparotomy was request by the responsible veterinarian. A mass, measuring about 20 cm was observed in the spleen and a splenectomy was requested. An increased of the kidney’s volume and an expansion of the renal pelvis and ureter were observed. The bladder wall had thickened and presented a firm consistency, an ureterocolonic anastomosis was requested by the responsible veterinarian. Total cystectomy was performed in a second surgical procedure. Six days after the second surgery the patient condition got worse. The dog presented abdominal pain signals and pale mucous membranes. The hematological and biochemistry analysis findings were, severe anemia, and elevated serum creatinine (6.12 mg/dL) and urea (263 mg/dL) levels. Based on severity of clinical signs and unfavorable prognosis the owners elected for euthanasia. Necropsy revealed a viscous material into the left ureter and in left renal pelvis, and papillary necrosis in the right kidney. The histologic assessment revealed tumor cells in regional lymph nodes and lungs. Discussion: The urinary diversion when consist of total cystectomy and ureteral transplantation to the gastrointestinal tract can be considered a therapeutic option in cases where the trigone is affected. In this study an ureterocolonic anastomosis was requested due to bilateral ureteral obstruction caused by TCC involving the trigone. Neurological and gastrointestinal signs, elevated serum creatinine levels and pyelonephritis may occur after surgery. Neurological signs were not observed. The dog, in the present case report, had already azotemia in pre-surgical examinations, probably caused by bilateral ureteral obstruction. One of the reasons for the increase in postoperative serum creatinine levels is chronic renal failure caused by ascending infection or post-renal obstruction. Another reason could also be reabsorption of the metabolite through the colon. Necropsy findings were ascending infection and pyelonephritis. Dilation of ureter at the time of surgery may have predisposed to the ascending infection. In previous studies aggressive surgical therapy did not result in a significant increase in survival time in dogs when compared to chemotherapy. Most dogs presented metastases, observed most frequently in lymph nodes and lungs. In this report the surgery was performed in an attempt to improve kidney function and life quality of the patient during hospitalization. The prognosis was considered unfavorable because of the advanced stage of the disease and kidney failure. The absence of an early diagnosis and inability to start early chemotherapy may result in a reduced in the survival time of these patients. Keywords: vesical neoplasm, hydronephrosis, urinary diversion, dogs

Estudo da combinação anestésica tiletamina-zolazepam-cetamina-xilazina (TCX), com ou sem metadona, em cães : determinação da DE50 e avaliação clínica

Este estudo teve como objetivo determinar a dose capaz de prevenir o movimento frente a um estímulo nocivo em 50% dos indivíduos (DE50) da combinação tiletamina-zolazepam-cetamina-xilazina (TCX) e TCX associada a 0,3 mg/kg de metadona (TCXM) em cães submetidos a cirurgia de orquiectomia. Trinta cães receberam aleatoriamente a administração do TCX (n = 14) ou TCXM (n = 16) pela via IM. A determinação da DE50 foi baseada no método up-and-down relatado por Dixon. O estímulo nociceptivo avaliado consistiu na incisão pré-escrotal de pele e tecido subcutâneo. Cada mL de TCX apresentou 50 mg de tiletamina, 50 mg de zolazepam, 80 mg de cetamina e 20 mg de xilazina. O volume inicial administrado no primeiro animal de cada grupo foi de 0,020 mL/kg. No caso de resposta positiva, a dose do TCX foi aumentada em 0,005 mL/kg para o paciente seguinte do mesmo grupo e o contrário ocorrendo frente a uma resposta negativa. Quando o anestesista julgava a anestesia inadequada, era administrado a complementação de 0,01 mL/kg de TCX pela via intramuscular e o bloqueio anestésico com lidocaína era realizado. Os animais permaneceram sob respiração espontânea em ar ambiente e foram avaliados parâmetros cardiovasculares e respiratórios. Os escores de sedação foram avaliados nos tempos basal e 15 minutos após a aplicação do tratamento. Os protocolos TCX e TCXM apresentaram curto período de latência (3 versus 4 minutos, respetivamente). Os cães de ambos os grupos apresentaram escores de sedação significativamente mais elevados 15 minutos após a aplicação do tratamento (medianas [intervalo interquartil]:TCX: 17 [6-20]; TCXM: 17 [13-21]) em relação ao basal (TCX: 3 [1-5]; TCXM: 3 [0-4]), sem diferença significativa entre grupos. Não houve diferença significativa na DE50 encontrada nos tratamentos TCX (0,024 ± 0,004 mL/kg) e TCXM (0,022 ± 0,005 mL/kg). Houve diferença significativa entre os grupos em relação a dose total de TCX para concluir a cirurgia de orquiectomia (P = 0,0001) e no grupo TCX, um maior número de complementações foi necessário (2 ± 1 versus 1 ± 1). A associação de metadona ao TCX não reduz a DE50 do TCX em cães, mas reduz o número de complementações e dose total necessária para concluir a cirurgia de orquiectomia. Os protocolos demonstram ser alternativa para rápida contenção química quando administrados em doses próximas à DE50.This study aimed to investigate the dose preventing movement in 50% of individuals in response to a noxious stimulus (ED50) of tiletamine-zolazepam-ketamine-xylazine (TCX) and tiletamine-zolazepam-ketamine-xylazine-methadone (TCXM) anesthetic combinations in dogs undergoing orchiectomy. Thirty dogs were randomly assigned to receive either TCX (n = 14) or TCXM (n = 16) IM. The ED50 value was obtained with Dixon's up-and-down method. The noxious stimulus applied was skin and subcutaneous pre-scrotal incision. Each milliliter of TCX contained 50 of tiletamine, 50 mg of zolazepam, 80 mg of ketamine and 20 mg of xylazine. The TCX anesthetic combination was injected intramuscularly and the initial dose administered in the first animal of each group was 0,020 mL/kg. When the individuals showed a positive response to the painful stimulus the dose was increased by 0,005 mL/kg to the next individual of the same group and the opposite occurred when a negative response was presented. In the TCXM group the patients received the TCX anesthetic combination plus 0,3 mg/kg methadone mixed in the same syringe. The TCX anesthetic combination was injected intramuscularly (0,01 mL/kg) and local anesthesia with lidocaine was performed when signs of inadequate anesthesia were observed. Anesthesia was maintained in dogs breathing room air spontaneously and cardiovascular and respiratory parameters were evaluated. Sedation scores were evaluated at baseline and 15 minutes after the treatment. The TCX and TCXM anesthetic combinations showed short latency period (3 versus 4 minutes respectively). The dogs showed significantly higher sedation scores 15 minutes after administration of treatments (median [interquartil range]: TCX: 17 [6-20]; TCXM: 17 [13-21]) when compared to baseline (TCX: 3 [1-5]; TCXM: 3 [0-4]), but there was no significant difference between groups. There was no significant difference between the ED50 of the TCX (0,024 ± 0,004 mL/kg) and TCXM (0,022 ± 0,005 mL/kg) groups. The total dose of TCX to completed the orchiectomy procedure was significantly higher in TCX than in TCXM (P = 0,0001). A larger number of additional doses of TCX was necessary in the TCX group than in TCXM (2±1 versus 1±1). The association of methadone with TCX does not reduce the ED50 of the TCX anesthetic combination, although it reduces the total dose required to complete the orchiectomy surgery. When administered in doses close to the ED50, TCX and TCXM seem to be a good alternative when rapid immobilization is required

Modified segmental vertebral stabilization in the treatment of spinal cord trauma in a Paraguaian hairy dwarf porcupine (Coendou spinosus) : case report

Uma fêmea, adulta, de ouriço-cacheiro (Coendou spinosus, F. Cuvier, 1823), foi atendida com histórico de trauma medular. No exame neurológico, foi constatada paraplegia com nocicepção preservada e sinais compatíveis com choque espinhal. Exame radiográfico e mielografia apontaram presença de fratura e luxação vertebral torácica entre T10-11. O paciente foi submetido à técnica de estabilização vertebral segmentar modificada, com pinos de Steinmann e fios de cerclagem. A técnica utilizada mostrou-se eficaz na estabilização da fratura/luxação vertebral e na recuperação dos sinais neurológicos. O paciente apresentou recuperação progressiva da deambulação. Para o conhecimento dos autores, este é o primeiro relato utilizando estabilização vertebral segmentar modificada para o tratamento de fratura/luxação vertebral torácica em Coendou spinosus.An female, adult Paraguayan hairy dwarf porcupine (Coendou spinosus, F. Cuvier, 1823) was referred to the Veterinary Hospital with clinical history of spinal cord injury. In the neurological examination, paraplegia with preserved nociception compatible with signs of spinal shock were observed. Radiographic and myelographic examinations showed evidence of a vertebral dislocation and fracture between the 10th and 11th thoracic vertebrae. The patient underwent surgical stabilization of the lesion using the modified segmental vertebral stabilization technique with Steinmann pins and cerclage wires. Under the conditions reported in this case, the technique was effective in stabilizing vertebral fracture/dislocation and in recovering neurological functions. The patient presented progressive recovery from ambulation. To the authors’ knowledge, this is the first case report that performed modified segment stabilization for thoracic vertebral fracture/luxation treatment in Coendou spinosus

Modified segmental vertebral stabilization in the treatment of spinal cord trauma in a Paraguaian hairy dwarf porcupine (Coendou spinosus) : case report

Uma fêmea, adulta, de ouriço-cacheiro (Coendou spinosus, F. Cuvier, 1823), foi atendida com histórico de trauma medular. No exame neurológico, foi constatada paraplegia com nocicepção preservada e sinais compatíveis com choque espinhal. Exame radiográfico e mielografia apontaram presença de fratura e luxação vertebral torácica entre T10-11. O paciente foi submetido à técnica de estabilização vertebral segmentar modificada, com pinos de Steinmann e fios de cerclagem. A técnica utilizada mostrou-se eficaz na estabilização da fratura/luxação vertebral e na recuperação dos sinais neurológicos. O paciente apresentou recuperação progressiva da deambulação. Para o conhecimento dos autores, este é o primeiro relato utilizando estabilização vertebral segmentar modificada para o tratamento de fratura/luxação vertebral torácica em Coendou spinosus.An female, adult Paraguayan hairy dwarf porcupine (Coendou spinosus, F. Cuvier, 1823) was referred to the Veterinary Hospital with clinical history of spinal cord injury. In the neurological examination, paraplegia with preserved nociception compatible with signs of spinal shock were observed. Radiographic and myelographic examinations showed evidence of a vertebral dislocation and fracture between the 10th and 11th thoracic vertebrae. The patient underwent surgical stabilization of the lesion using the modified segmental vertebral stabilization technique with Steinmann pins and cerclage wires. Under the conditions reported in this case, the technique was effective in stabilizing vertebral fracture/dislocation and in recovering neurological functions. The patient presented progressive recovery from ambulation. To the authors’ knowledge, this is the first case report that performed modified segment stabilization for thoracic vertebral fracture/luxation treatment in Coendou spinosus

Abordagens subzigomática e infraorbitária para o bloqueio do nervo maxilar em cadáver de gatos

This study compared the accuracy of dye placement on the maxillary nerve by using the percutaneous subzigomatic (SBZ) and infraorbitary (IO) approaches in cats’ cadavers. A second aim was to compare the accuracy of dye placement on the maxillary nerve between different untrained anesthetists. This was a prospective, randomized, blinded study, performed in 40 heads obtained from feline cadavers. Three veterinarians (A, B and C) with no previous experience with the IO approach performed the experiments. The SBZ approach was randomly performed on one side of the head and the IO approach was performed in the contralateral side of the same head. For each approach, 0.2ml of 1% methylene blue dye was injected. Scores for length of nerve staining were as follows: 0 (failure), no staining; 1 (moderate), <6mm of nerve stained; and 2 (ideal), ≥6mm of nerve stained. Median scores (interquartile range) for the SBZ and IO approaches were 2.0 (0.3-2.0) and 1.0 (0.0-2.0), respectively. Scores for length of nerve staining were higher with the SBZ approach than the IO approach (P=0.016). Considering the scores for both the SBZ and IO approaches, there was a significant difference among the three veterinarians (P=0.002). Results of this study do not support the IO approach to perform a maxillary nerve block in cats. A greater accuracy of methylene blue dye placement was observed with the SBZ approach. A variable accuracy may exist between different veterinarians when performing a maxillary nerve block employing the SBZ and IO techniques in cats.O objetivo deste estudo foi comparar o acesso do nervo maxilar pela abordagem subzigomática (SBZ) com a abordagem pelo forame infraorbitário (IO) em peças anatômicas de gatos utilizando o corante azul de metileno. Um segundo objetivo foi comparar a acurácia na coloração do nervo maxilar com o azul de metileno entre diferentes anestesistas que não receberam treinamento prévio. Este estudo foi prospectivo, randomizado, cego, realizado em 40 peças anatômicas de cabeças de gatos. Três veterinários (A, B e C), sem experiência prévia da abordagem IO, realizaram o experimento. A abordagem SBZ foi aleatoriamente realizada em um dos lados da cabeça e a abordagem IO foi realizada no lado contralateral da mesma peça anatômica. Para cada abordagem, utilizou-se 0,2mL do corante azul de metileno 1%. Classificou-se o escore de coloração baseado no comprimento do nervo maxilar corado pelo azul de metileno conforme a escala: 0 (falha da técnica), sem coloração; 1 (moderado), <6mm de coloração do nervo maxilar; 2 (ideal), ≥6mm de coloração do nervo maxilar. As medianas (intervalo interquartil) para as abordagens SBZ e IO (dados de todos os veterinários juntos) foram respectivamente 2,0 (0,3-2,0) e 1,0 (0,0-2,0). A abordagem SBZ foi associada a um escore de coloração, significativamente, maior do que a abordagem IO (P=0,016). Considerando os escores de ambas abordagens (SBZ e IO), houve diferença significativa nos escores de coloração do nervo maxilar entre os três veterinários anestesistas (P=0,002). Os resultados deste estudo não sustentam a utilização da abordagem IO para a realização do bloqueio maxilar em gatos. Uma melhor acurácia na coloração do nervo maxilar com o azul de metileno foi observada com a abordagem SBZ. A acurácia da técnica pode variar quando as abordagens SBZ e IO são realizadas por veterinários diferentes, com o objetivo de se obter o bloqueio do nervo maxila

Subzygomatic and infraorbital approaches for maxillary nerve blockade in cats’ cadaver

<div><p>ABSTRACT: This study compared the accuracy of dye placement on the maxillary nerve by using the percutaneous subzigomatic (SBZ) and infraorbitary (IO) approaches in cats’ cadavers. A second aim was to compare the accuracy of dye placement on the maxillary nerve between different untrained anesthetists. This was a prospective, randomized, blinded study, performed in 40 heads obtained from feline cadavers. Three veterinarians (A, B and C) with no previous experience with the IO approach performed the experiments. The SBZ approach was randomly performed on one side of the head and the IO approach was performed in the contralateral side of the same head. For each approach, 0.2ml of 1% methylene blue dye was injected. Scores for length of nerve staining were as follows: 0 (failure), no staining; 1 (moderate), <6mm of nerve stained; and 2 (ideal), ≥6mm of nerve stained. Median scores (interquartile range) for the SBZ and IO approaches were 2.0 (0.3-2.0) and 1.0 (0.0-2.0), respectively. Scores for length of nerve staining were higher with the SBZ approach than the IO approach (P=0.016). Considering the scores for both the SBZ and IO approaches, there was a significant difference among the three veterinarians (P=0.002). Results of this study do not support the IO approach to perform a maxillary nerve block in cats. A greater accuracy of methylene blue dye placement was observed with the SBZ approach. A variable accuracy may exist between different veterinarians when performing a maxillary nerve block employing the SBZ and IO techniques in cats.</p></div