Cranial epidural anesthesia with lidocaine and morphine for sterilization campaign in dogs/Anestesia epidural cranial com lidocaina e morfina para campanhas de castracao em caes

• Published in: Ciência rural Vol. 40; no. 1
• Main Authors: Tamanho, Renato Batista, Oleskovicz, Nilson, de Moraes, Aury Nunes, Flores, Fabiola Niederauer, Dallabrida, Ademar Luiz, Regalin, Doughlas, Carneiro, Ruiney, Pacheco, Acacio Duarte, da Rosa, Ademir Cassiano da
• Format: Journal Article
• Language: Spanish
• Published: Universidade Federal de Santa Maria 01.01.2010
• Subjects: Anesthesia; Dogs; Morphine
• ISSN: 0103-8478

Male and female sterilization have been established as the main technique to reduce the huge number of mongrel dogs. However, there are several barriers regarding to the choice of the best anesthetic protocol, in terms of efficacy, security and cost reduction. The aim of this study was to evaluate the analgesic, cardiorespiratory and hemogasometric effects of epidural anesthesia with a large volume of lidocaine in combination with morphine in female dogs submitted to ovariosalpingohisterectomy (OSH), with or without oxygen supplementation. Twelve adult female dogs were used, with average weight of 11.5 [+ or -] 3.7kg and age of 1 to 4 years. The animals received acepromazine (0.1mg [kg.sup.-1]) and meperidine (5mg [kg.sup.-1]) as premedication, administered by the intramuscular route. Fifteen minutes later, thiopental (10mg [kg.sup.-1]) was administered by intravenous route, followed by endotracheal intubation. The animals were allocated into two groups: GCO (group with oxygen, n=06), where the animals received 100% oxygen supplementation and GSO (group without oxygen supplementation, n = 6), mantained with endotracheal intubation, but without oxygen supplementation. After intubation, epidural with morphine (0,1mg [kg.sup.-1]), adjusted to 1mL 3[kg.sup.-1] in lidocaine 2% without epinepherine was administered. Immediately after epidural administration, the animals were positioned in dorsal recumbency, with the head in the same level of the body. In both groups, surgery was performed without the need of additional analgesia and without signs of pain. Mean arterial pressure (MAP) was lower in GSO in all moments compared to baseline values. In GCO, MAP was lower after premedication and epidural anesthesia. Respiratory rate was lower from M1 to M6 in GSO. The SaO2 and Pa[O.sub.2] were higher in GCO when compared to GSO. The pH was lower in GCO after 15 minutes after premedication, until 40 minutes after the epidural administration, compared to GSO. It was concluded that the epidural administration using morphine and lidocaine in the dosage and volume proposed are effective to OSH procedure in dogs. The lack of oxygen supplementation promoted minimal cardiovascular and hemogasometric alterations, which is feasible in sterilizations campaigns where there is no possibility of oxygen supplementation of the animals. Key words: dogs, morphine, epidural, sterilizations campaigns. A castracao de machos e femeas tem sido preconizada como a principal tecnica para reducao do grande numero de caes errantes. No entanto, varios sao os entraves com relacao a escolha do melhor protocolo anestesico, em relacao a eficacia, seguranca e reducao de custos. Objetivouse, com este trabalho, avaliar os efeitos cardiorrespiratorios, hemogasometricos e analgesicos da utilizacao de lidocaina em um volume maior, associada a morfina, pela via epidural em cadelas submetidas a ovariosalpingohisterectomia (OSH), com ou sem suplementacao de oxigenio. Utilizaram-se 12 cadelas, com peso medio de 11,5 [+ or -] 3,7kg e idade de um a quatro anos. Os animais receberam como medicacao preanestesica (MPA) acepromazina (0,1mg [kg.sup.-1] ) e meperidina (5mg [kg.sup.-1]), pela via intramuscular. Apos 15 minutos, administrou-se tiopental (10mg [kg.sup.-1]), por via intravenosa, seguido de intubacao endotraqueal. Nesse momento, os animais foram alocados em dois grupos: o grupo GCO (com oxigenio, n=06) recebeu suplementacao de oxigenio 100% e o grupo GSO (sem oxigenio, n=06) permaneceu intubado sem suplementacao de oxigenio. Apos a intubacao, foi administrada, pela via epidural, em ambos os grupos, morfina (0,1mg [kg.sup.-1]) em volume final ajustado para 1mL 3,0[kg.sup.-1] de peso com lidocaina 2% sem vasoconstritor. imediatamente apos a anestesia epidural, os animais foram posicionados em decubito dorsal com a cabeca no mesmo plano do corpo, e iniciou-se o procedimento cirurgico, o qual foi padronizado em 30 minutos. Em ambos os grupos, foi possivel realizar a cirurgia sem a necessidade de complementacao analgesica e sem resposta de dor. A pressao arterial media (PAM) foi menor no GSO em todos os momentos em comparacao ao basal. No GCO, a PAM foi menor apos MPA e apos epidural. Houve reducao da f de M1 ate M6 no GSO. A Sa[O.sub.2] e Pa[O.sub.2] foram maiores no GCO em comparacao ao GSO. O pH foi menor no GCO 15 minutos apos MPA ate 40 minutos apos epidural, em comparacao ao GSO. Conclui-se que a anestesia epidural lombossacra com morfina e lidocaina na dose e no volume propostos e efetiva para realizacao de OSH em cadelas, com minimas alteracoes cardiovasculares e hemogasometricas, as quais sao bem toleradas em animais higidos. Essa pratica e exequivel em campanhas de castracao em que nao ha possibilidade de oxigenacao dos animais. Palavras-chave: caes, morfina, epidural, campanhas de castracao.