Cardiovascular and eletrocardiographics effects of methadone and morphine in dogs anesthetized with continuous infusion of propofol

• Grant number: 08/00835-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2008
• End date: November 30, 2009
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Clinics and Surgery
• Principal Investigator: Celina Tie Nishimori Duque
• Grantee: Priscila Pavini Cintra
• Host Institution: Pró-Reitoria Adjunta de Pesquisa e Pós-Graduação. Universidade de Franca (UNIFRAN). Franca , SP, Brazil

Abstract

Total intravenous anesthesia is an anesthetic technique that has been used frequently in Veterinary Anesthesiology clinical practice. So, researches are hoping to improve the knowledge about drugs to find newer and safer techniques and associations to maintain patient cardiovascular and respiratory stability during procedure.Propofol is an intravenous hypnotic with short action commonly used to induction and maintenance of anesthesia in dogs, because rapidly, calmly and safety unconsciousness promoted in healthy animals, besides minimal cumulative effect. However, this drug is not a good analgesic, so it is necessary to associate to other agents to induce analgesia.Methadone is an agonist-m (OP3) synthetic opioid that has additional affinity to N-metil-D-aspartate (NMDA) and a-2 adrenergics receptors. It has analgesic effect farmacologically similar to morphine. This drug has been used as preanesthetic medication in addition to tranquilizers or sedatives to produce profound sedation, or during perioperative period in dogs, cats and horses.There is not a lot of information available referring to effects of methadone administration as analgesic, or as adjunct of anesthesia with propofol in dogs. So, it was considered important to evaluate cardiovascular and electrocardiographics effects of methadone when compared to morphine, in dogs anesthetized with continuous infusion of propofol.