Ropivacaine sole or associated with morphine, butorphanol or tramadol by epidural injected in the bitches for ovariosalpingohisterctomy accomplishment/Ropivacaina isolada ou associada a morfina, butorfanol ou tramadol pela via peridural em cadelas para realizacao de ovariosalpingohisterectomia/Ropivacaina aislada o asociada a la morfina, butorfanol o tramadol por via peridural en perras para realizacion de ovariosalpingohisterectomia

The aim of this study was to investigate the use of ropivacaine combined or not with different opioids, for epidural anesthesia in bitches submitted to elective ovariosalpingohisterectomy (OSH). Thirty two mixed-breed female dogs, adults were used with medium weigh of 10.5kg. The animals were premedicated with acepromazine (0.05mg.[kg.sup.-1], IM) and midazolam (0.2mg.[kg.sup.-1], IM) and allocated in four experimental groups: group 1(n = 8): ropivacaine: 0.3 mL.[kg.sup.-1]; group 2(n = 8): ropivacaine + morphine (0.1 mg.[kg.sup.-1]); group 3(n = 8): ropivacaine + butorphanol (0.1 mg.[kg.sup.-1]); and group 4(n = 8): ropivacaine + tramadol (0.5 mg.[kg.sup.-1]) administered epidurally. Heart and respiratory rate; systolic arterial pressure; rectal temperature; arterial blood gas partial pressures; blood pH; sedation and muscular relaxation degree were evaluated at different experimental moments. The data were submitted to ANOVA and compared by Kruskal Wallis, Friedman, Dunn, Tukey and Chi-square test (p [less than or equal to] 0.05). Minimum cardiorespiratory alterations were observed and the group of the ropivacaine combined with the butorphanol (G3) presented a more cranial blockage, what allowed the accomplishment of OSH without induction in six animals (75%) whereas most of the others needed anesthetic rescue. The results allow us to conclude that the use of ropivacaine sole or combinated with morphine, butorphanol or tramadol, for epidural anesthesia, didn't promote significant cardiorrespiratory depression and the ropivacaine associated to the butorphanol allowed the accomplishment of OSH in bitches. Keywords: bitches, opioids, ovariosalpingohisterectomy, epidural, ropivacaine. O presente trabalho teve como objetivo investigar a utilizacao da ropivacaina isolada ou em associacao a diferentes opioides, na anestesia peridural de cadelas submetidas a ovariosalpingohisterectomia (OSH) eletiva. Participaram do estudo, 32 cadelas sadias, adultas, de diferentes racas, com peso medio de 10,5kg, as quais foram pre-medicadas com acepromazina (0,05mg/kg, IM) associada ao midazolam (0,2mg/kg, IM), distribuidas em quatro grupos distintos: Grupo 1(n = 8): ropivacaina: 0,3 mL/kg; Grupo 2(n = 8): ropivacaina + morfina (0,1 mg/kg); Grupo 3(n = 8): ropivacaina + butorfanol (0,1 mg/kg); e Grupo 4(n = 8): ropivacaina + tramadol (0,5 mg/kg) administrados pela via peridural. Foram mensurados: frequencia cardiaca; frequencia respiratoria; pressao arterial sistolica; tempera