Epidural technique with use of lidocaine and bupivacaine associated with fentanyl in bitches submitted to ovarian oysterectomy

Abstract

The increasing interest in veterinary anesthesiology observed in recent years is the result of the recognition of this specialty as fundamental to the practice of veterinary medicine, since the more extensive the knowledge about existing anesthetic techniques, the better the choice to be made. The objective of this study was to compare the effects of two anesthetic protocols on bitches submitted to ovarian oysterectomy, with acepromazine and tramadol, midazolam and propofol as an anesthetic inducing agent together with epidural combinations with lidocaine-fentanyl and bupivacaine-fentanyl , in order to observe the effects caused by the physiological variables, duration and quality of the anesthesia, 15 undefined (SRD) bitches with a mean weight of 12.26, healthy, were used from shelters that were allocated in three groups according to the protocol to be applied. Heart rate, respiratory rate and body temperature were evaluated; as well as the average dose of anesthetics, sensory, motor and anal reflex. The heart rate values, although slightly altered, remained within the normal physiological parameters for the canine species. The respiratory rate in the fentanyl-lidocaine group had a significant change from baseline. Discrete hypothermia was recorded in animals of all groups, more severely in the fentanyl-bupivacaine group. The motor and sensory reflex in the fentanyl-bupivacaine group occurred more delayed than in the fentanyl-lidocaine group and that some animals in the fentanyl lidocaine group had adverse effects such as salivation and relaxation of the anal sphincter to the point of defecation. Therefore, it is concluded that the technique that uses fentanyl associated with bupivacaine is more advisable for ovarian resection surgery, because it has a greater nociceptive block, greater relaxation and consequently results in greater comfort for the animal during trans and post-surgery.