Epidural levobupivacaine alone or combined with different morphine doses in bitches under continuous propofol infusion

Abstract

The aim of this study was to assess the cardiopulmonary, analgesic, adverse effects, serum concentration of cortisol and plasma levels of levobupivacaine and morphine in bitches undergoing propofol anesthesia and epidural analgesia with levobupivacaine alone or combined with morphine. This was a randomized 'blinded' prospective clinical study using 32 adult bitches weighing 9.8±4.1kg that were admitted for elective ovariohysterectomy. Twenty minutes after administration of acepromazine and midazolam, anesthesia was induced with propofol (4mg kg -1 ) and maintained by a continuous rate infusion (CRI). Each animal was randomly assigned to one of four epidural groups: GL = levobupivacaine alone (0.33mg kg -1 ); GLM0.1 = levobupivacaine and morphine (0.1mg kg -1 ); GLM0.15 = levobupivacaine and morphine (0.15mg kg -1 ); and GLM0.2 = levobupivacaine and morphine (0.2mg kg -1 ). Variables obtained during anesthesia were heart rate, respiratory rate, systolic, mean and diastolic arterial blood pressures, oxyhemoglobin saturation, inspired oxygen fraction, end-tidal carbon dioxide tension, blood gases, serum cortisol, and plasma levels of levobupivacaine and morphine. The onset and duration times of the blockade were recorded. Arterial pressures were significantly increased in all groups at the times of ovarian pedicle clamping. There was a decrease in pH, together with an increase in both PaO 2 and PaCO 2 over time. Serum cortisol levels were increased in TESu compared to TB, T30 and TR. Limb spasticity, muscle tremors, opisthotonos and diarrhea were observed in some animals during propofol infusion and ceased with the end of CRI. Reactions happened at different moments and lasted for different periods of time in each individual. Epidural with levobupivacaine alone or combined with morphine allowed for ovariohysterectomy to be performed under low propofol infusion rates, with minimal changes in cardiovascular variables and in serum cortisol levels. Adverse effects were observed in very few animals in each group. Keywords: dog, opioid, ovariohysterectomy, blood gas, regional anaesthesia (0,33mg/kg); GLM0,1 = levobupivacaína + morfina (0,1mg/kg); GLM0,15 = levobupivacaína + morfina (0,15mg/kg) e GLM0,2 = levobupivacaína + morfina (0,2mg/kg RESUMO Objetivou-se avaliar os efeitos cardiovasculares, analgésico, adversos, a concentração sérica de cortisol e os níveis plasmáticos de levobupivacaína e morfina em cadelas submetidas à infusão contínua de propofol e analgesia peridural com levobupivacaína isolada ou associada à morfina. Para tanto, realizou-se um estudo clínico prospectivo randomizado com 32 cadelas adultas pesando 9,8 ± 4,1kg, que foram submetidas à ovário-histerectomia eletiva. Vinte minutos após a administração de acepromazina e midazolam, os animais foram induzidos com propofol (4mg/kg) e mantidos por uma infusão contínua (CRI) do mesmo fármaco. Cada animal foi alocado aleatoriamente em um dos quatro grupos: GL = levobupivacaína isolada

Different rates of tramadol infusion for peri and postoperative analgesia in dogs undergoing orthopedic surgery

“…Cortisol levels showed an increase over time during the postoperative period, which can be related to clearance of tramadol and onset of postoperative pain. Albuquerque et al (2015) have reported higher levels of cortisol during ovariohysterectomies at the time of vessel clamping when compared to physiological levels, corroborating another study by Paolozzi et al (2011) and the present study. At T1, serum cortisol increased significantly, suggesting that tramadol, regardless of the rate of infusion, did not inhibit the stress response caused by surgical trauma.…”

Influência do tramadol associado à levobupicavaína epidural sobre a taxa de propofol e variáveis fisiológicas, em cadelas submetidas à mastectomia e à ovário-histerectomia

“…Em contrapartida, a taxa média de propofol maior no grupo tratado apenas com levobupivacaína aventa a hipótese de potencialização anestésica pelo tramadol, independentemente das doses propostas. Embora a literatura seja escassa relativamente ao efeito poupador de propofol da analgesia epidural com opioides, em cadelas submetidas à ováriohisterectomia, por tal via, o uso da levobupivacaína isolada, ou associada a três diferentes doses de morfina, demonstrou similarmente redução das taxas do alquifenol com o incremento das doses do opioide (Albuquerque et al, 2015).…”

“…Os anestésicos locais são vastamente explorados e a levobupivacaína destaca-se como o enantiômero S (-) puro da bupivacaína, que surgiu fortemente como opção mais segura à forma racêmica, com comparável efetividade de bloqueio sensorial cirúrgico (Bajwa e Kaur, 2013). Em cães, demonstra eficácia epidural, apresentando-se como boa alternativa para cirurgias abdominais e pélvicas, em uso isolado ou associada a opioides (Albuquerque et al, 2015;Cerasoli et al, 2017).…”