Effects of methadone and acepromazine or methadone and detomidine on dissociative anaesthesia in horses

• Grant number: 16/04462-7
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): June 01, 2016
• Effective date (End): May 31, 2017
• Field of knowledge: Agronomical Sciences - Veterinary Medicine
• Principal Investigator: Adriano Bonfim Carregaro
• Grantee: Giuliana Izumi Ueda
• Home Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil

Abstract

The aim of this study is to assess the quality of sedation using two different neuroleptoanalgesia protocols and their influence in the dissociative anesthesia of healthy horses, comproved by laboratorial exams (CBC and biochemical tests). Six adult crossbred animals of both genders will be used in the study. Each animal will undergo two preanesthesic medication protocols, with at least amonth washout period, for total excretion of the drugs. Animals in experimental group MD will receive 0.1 mg/kg of methadone and 0.03mg/kg of detomidine, and animals in MA will receive 0.1 mg/kg of methadone and 0,03 mg/kg of acepromazine, both intravenously (IV). Both groups will receive for anesthesic induction 3mg/kg of ketamine and 0,1 mg/kg midazolam IV. The qualities of sedation, induction and recovery will be assessed by descriptive scales cited in literature. Furthermore, duration of anesthetic induction, maintenance and recovery, and physiological parameters, such as temperature, cardiac rate, respiratory rate, arterial blood pressure and intestinal motility before the premedication (0 min), right after the anesthesic induction (20 min) and then will be assessed every 5 minutes, until the begin of recovery. It is expected that animals from MD show better sedation, induction and recovery qualities than MA.