Eficácia analgésica da metadona associada a infusão contínua de fentanil, cetamina e lidocaína no pós-operatório imediato de cadelas submetidas a ovariossalpingohisterectomia

Abstract

Analgesia in different operative times is one of the goals of any anesthetic technique. In this context, the use of opioid agents in order to meet this goal has become a common practice. Objective is to evaluate the immediate postoperative analgesia association of methadone, fentanyl, ketamine, intravenous lidocaine during ovariohysterectomy surgery in dogs. They used 16 dogs divided into two groups of 8 animals, methadone group (G1) and control group (G2). As premedication in G1 used to acepromazine association (0.05mg / kg) and methadone (0.1 mg / kg) in G2 only acepromazine was used. At induction, was used ketamine (1 mg / kg), lidocaine (1 mg / kg), fentanyl (2UG / kg) and midazolam (0.5mg / kg) in both groups. At continuous infusion, was utilized ketamine (10mg / kg / min), lidocaine (50ug / kg / min), fentanyl (0.03 ug / kg / min) and Methadone (0.2mg / kg / min) and G2 He received the same brewing without methadone. For evaluation of post-operative analgesia, the animals were examined in a double-blind scheme, with one reviewer at different times every 30 minutes for 120 minutes after surgery, using the pain scale, University of Melbourne. In the present study, the majority of animals in both groups remained the HR and RR within the acceptable range for the species. G1 had lower scores when evaluated analgesia postoperatively, suggesting a lower response to painful stimuli, confirming that the proposed protocol in G1, with the use of methadone, showed better results and greater analgesic effect after the surgery.