Analgesic, cardiorespiratory effects and motor block characteristics of epidural levobupivacaine alone or in combination with methadone or dexmedetomidine in bitches undergoing unilateral total mastectomy.

The aim of this study was to evaluate the latency, extent of analgesia, and duration of motor block of levobupivacaine alone and combined with methadone or dexmedetomidine after epidural administration during and after mastectomy in dogs. Twenty-four mature, mixed-breed female dogs were randomly divided into three experimental groups with eight animals each, according to the agents used in lumbosacral epidural analgesia: levobupivacaine 0.75% alone (1.5mg/kg - control group), levobupivacaine 0.75% (1.5 mg/kg) + methadone 1% (0.3 mg/kg), or levobupivacaine 0.75% (1.5 mg/kg) + dexmedetomidine 0.05% (3 µg/kg). During surgery, cardiorespiratory parameters were evaluated. Rescue analgesia was given when there were signs of nociception and was necessary in all three treatment groups. Since all animals received rescue analgesia during the surgery and immediately post-surgery, the duration of the sensitive block were not evaluated. The extent of sensory block was between the 12º and 13º thoracic vertebrae for the control group, 7º thoracic vertebra to 5º lumbar vertebra (methadone group), and 8º thoracic vertebra to 4º lumbar vertebra for the dexmedetomidine group. Methadone or dexmedetomidine combined with levobupivacaine increased the extent of the sensory block and the duration of the motor block in bitches when administered via the epidural route.

Vitality evaluation methods for newborn puppies after cesarean section performed under general inhalation anestesia / Métodos de avaliação da vitalidade neonatal de cães após cesariana sob anestesia geral inalatória

This study aimed to demonstrate and to correlate possible methods for neonatal assessment in dogs born by elective cesarean surgery using inhalation anesthesia, enhancing its advantages and disadvantages as well as proposing lactate measurement as an adjunctive method of evaluation. After elective cesarean surgery of four bitches subjected to morphine premedication followed by propofol induction and sevoflurane anesthesia, 30 neonates were evaluated through blood sampling from the umbilical cord for lactate measurement and blood gas analyses, as well as neurological and cardiorespiratory assessment at birth and at 10 minutes of age. The neonates presented respiratory acidosis and acidemia at birth related to blood lactate values (4.98±1.39mmol/L). Neurological and cardiorespiratory depressions were present at birth with recovery at 10 minutes and no complications were observed during the first 30 days of life. The methods for neonatal assessment used in this study are safe when appropriately interpreted and the effects of general anesthesia on neonates were transient. Blood lactate obtained from the umbilical cord can be an option for the evaluation of these patients.(AU)

Objetivou-se demonstrar e correlacionar os possíveis métodos de avaliação neonatal de filhotes de cães nascidos de cesarianas eletivas com a utilização de anestesia inalatória, apontando suas vantagens e desvantagens e propor a dosagem de lactato sanguíneo como prática auxiliar. Após a cesariana eletiva em quatro cadelas submetidas ao protocolo anestésico composto de morfina, propofol e sevofluorano, foram avaliados 30 neonatos com exames de sangue do cordão umbilical para dosagem de lactato e gases sanguíneos, avaliação neurológica e cardiorrespiratória realizadas no nascimento e aos 10 minutos de vida. Os animais apresentaram acidose respiratória com acidemia ao nascimento, associados a altos valores de lactato sanguíneo (4,89±1,39mmol/L). Ocorreu depressão neurológica e cardiorrespiratória no nascimento, com recuperação após 10 minutos, sem complicações nos primeiros 30 dias. Pode-se concluir que os métodos de avaliação neonatal utilizados são seguros quando interpretados adequadamente e os efeitos da anestesia nos neonatos foram transitórios. O lactato do sangue umbilical pode ser opção na avaliação desses pacientes.(AU)

Evaluation of cardiopulmonary parameters and recovery from anesthesia in cougars (Puma concolor) anesthetized with detomidine/ketamine and isoflurane or sevoflurane / Avaliação de parâmetros cardiorrespiratórios e recuperação da anestesia em pumas (Puma concolor) anestesiados com detomidina/cetamina e isoflurano ou sevoflurano

The aim of this study was to assess the cardiopulmonary effects, the onset time after the administration of a detomidine/ketamine combination, and the recovery from anesthesia of cougars (Puma concolor) anesthetized with detomidine/ketamine and isoflurane or sevoflurane for abdominal ultrasound imaging. Fourteen animals were randomly allocated into two experimental groups: GISO (n=7) and GSEVO (n=7). Chemical restraint was performed using 0.15mg/kg detomidine combined with 5mg/kg ketamine intramuscularly; anesthesia induction was achieved using 2mg/kg propofol intravenously and maintenance with isoflurane (GISO) or sevoflurane (GSEVO). The following parameters were assessed: heart rate, respiratory rate, systolic and diastolic arterial blood pressure, mean arterial blood pressure, oxyhemoglobin saturation, rectal temperature, central venous pressure, and end-tidal carbon dioxide. The time to sternal recumbency (TSR) and time to standing position (TSP) were also determined. There was not statistically significant difference for the cardiopulmonary variables or TSP whereas TSR was significantly shorter in GSEVO. The time to onset of anesthesia was 11.1±1.2 minutes and 11.3±1.8 minutes for GISO and GSEVO, respectively. The anesthesia of cougars with detomidine/ketamine and isoflurane or sevoflurane was conducted with safety, cardiopulmonary stability, and increased time to sternal recumbency in the GISO group.

O objetivo do presente estudo foi avaliar os efeitos cardiorrespiratórios e a recuperação anestésica de onças-pardas (Puma concolor) submetidas à anestesia com detomidina/cetamina e isofluorano ou sevofluorano para avaliação ultrassonográfica abdominal. Para isso, foram utilizados 14 animais divididos aleatoriamente em dois grupos experimentais GISO (n=7) e GSEVO (n=7). Foram submetidos à contenção química com detomidina 0,15mg/kg associada à cetamina 5mg/kg pela via intramuscular, induzidos com propofol 2mg/kg pela via intravenosa e mantidos com isofluorano (GISO) ou sevofluorano. Foram avaliados os parâmetros: frequência cardíaca e respiratória, pressão arterial sistólica, média e diastólica saturação de oxihemoglobina, temperatura retal, pressão venosa central e fração expirada de dióxido de carbono. O tempo para adoção de decúbito esternal e posição quadrupedal também foram avaliados. Não houve diferença estatística para as variáveis cardiorrespiratórias e no tempo para adoção da posição quadrupedal. O tempo para adoção de decúbito esternal foi significativamente menor no GSEVO em relação ao GISO. Concluiu-se que a anestesia de onças pardas com detomidina/cetamina e isoflurano ou sevoflurano foi realizada de maneira segura, com estabilidade cardiorrespiratória e com aumento no tempo para adoção de decúbito esternal no GISO.

Cardiopulmonary and analgesic effects of caudal epidurally administered ropivacaine in cattle.

OBJECTIVE: To assess cardiopulmonary and analgesic effects after administration of ropivacaine into the caudal epidural space of cattle. STUDY DESIGN: Prospective, single-dose trial. ANIMALS: Eight healthy mixed breed cows aged 8 ± 5 years and weighing 507 ± 112 kg. METHODS: Caudal epidural anesthesia was produced in cows with 0.75% ropivacaine (0.11 mg kg(-1)). Onset time, duration and cranial spread of analgesia were recorded. Heart rate (HR), respiratory rate (f(R)), rectal temperature (RT), and mean arterial blood pressure (MAP) were measured prior to epidural administration (T(0) ) and at 15, 30, 60, 120, 180 and 240 minutes after epidural administration (T(15), T(30), T(60) , T(120) , T(180) and T(240) ). Arterial blood acid-base balance (pH, standard bicarbonate and base excess), gas tension (PaO(2), PaCO(2), SaO(2)) and electrolytes (Na(+), K(+), iCa(2+),Cl(-)) were recorded at T(0), T(30), T(60), T(120), T(180) and T(240). Ataxia was evaluated at T(0), T(30), T(60), T(120), T(180) and T(240) and at 1 hour intervals thereafter until analgesia was no longer present in each animal. RESULTS: Epidurally administered ropivacaine induced variable analgesia extending bilaterally from the coccyx to S3. Time to onset of analgesia and mean duration in the perineal area were 15 ± 4 and 359 ± 90 minutes, respectively. Respiratory rate and RT increased from T(120) to T(240) when compared to the value at T(0) . Ionized calcium and chloride concentrations increased at T(180) and T(240) when compared to T(0). The other variables were not significantly different from baseline values (p > 0.05). Four animals were mildly ataxic. CONCLUSION AND CLINICAL RELEVANCE: Ropivacaine (0.75%, 0.11 mg kg(-1)) can be administered by caudal epidural injection to produce prolonged bilateral perineal analgesia with minimal ataxia and cardiopulmonary changes in standing cattle.