RESUMO
OBJECTIVE: To determine the median effective dose (ED50) of intravenous (IV) bupivacaine associated with a 50% probability of causing clinically relevant cardiovascular effects [defined as 30% change in heart rate (HR) or mean arterial pressure (MAP)] in chickens anesthetized with isoflurane. STUDY DESIGN: Randomized up-and-down study. ANIMALS: A total of 14 Ross-708 broiler chickens (Gallus gallus domesticus) weighing 1.70-2.75 kg. METHODS: Anesthesia was induced and maintained with isoflurane. Monitoring included the electrocardiogram and invasive arterial pressures. Chickens were administered bupivacaine IV over 2 minutes using a dose based on the response of the previous animal. Dose was decreased when HR and/or MAP in the previous animal increased or decreased ≥30% after bupivacaine administration, or increased when HR or MAP changed <30%. The ED50 was defined as the dose resulting in ≥30% variation in HR or MAP in 50% of the population studied. RESULTS: The IV ED50 of bupivacaine was 1.94 mg kg-1 using Dixon's up-and-down method and 1.96 mg kg-1 by logistic regression. CONCLUSIONS AND CLINICAL RELEVANCE: These results suggest that 1.33 and 1.96 mg kg-1 of IV bupivacaine are associated with a respective 1 or 50% probability of a clinically significant change in MAP in isoflurane-anesthetized chickens. Identification of the cardiovascular changes associated with different doses of bupivacaine can be used as the basis for studies of therapeutic applications in the domestic chicken. Further studies are required to determine interspecies variation.
Assuntos
Anestésicos Inalatórios , Anestésicos Locais/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Bupivacaína/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Isoflurano , Animais , GalinhasRESUMO
A toy Australian shepherd dog was referred for bile peritonitis following excision of a biliary mucocele. Subsequent delayed gastric emptying was refractory to prokinetic therapy but responded to injection of botulinum toxin A into the muscularis layer of the pylorus; a novel therapy for delayed gastric emptying in dogs.
Toxine botulinique : Traitement de la vidange gastrique retardée chez un chien. Un chien Berger australien miniature a été référé pour une péritonite biliaire après l'excision d'une mucocèle biliaire. La vidange gastrique retardée subséquente a été réfractaire au traitement stimulant la motilité gastrique mais a répondu à l'injection de la toxine botulinique A dans la couche musculeuse du pylore; un traitement innovateur pour la vidange gastrique retardée chez les chiens.(Traduit par Isabelle Vallières).
