Anestesia total intravenosa com propofol associado ao fentanil, lidocaínaou cetamina em cadelas submetidas à ovariossalpingohisterectomia eletiva / Total intravenous anesthesia with propofol associated with fentanyl, lidocaine or ketamine in bitches submitted to elective ovariohysterectomy

ABSTRACT

Background: Total intravenous anesthesia with propofol is an alternative to inhalation anesthesia because it offers smoother anesthetic recovery, however, since propofol does not have adequate analgesic action, it is necessary to associate it with some drug to avoid the pain process. In addition, the combination may minimize cardiovascular depression resulting from continuous infusion of propofol by reducing infusion rate. The aim of this study was to evaluate cardiorespiratory parameters and anesthetic recovery in bitches submitted to continuous infusion of fentanyl, lidocaine and ketamine associated with total intravenous anesthesia with propofol and submitted to elective ovariohisterectomy. Materials, Methods & Results: Twenty-four bitches were medicated intramuscularly with 0.03 mg/kg of acepromazine. After 30 min, they were divided into three groups with different analgesic treatments group F (GF) received a loading dose (LD) of 0.0036 mg/kg fentanyl, followed by continuous infusion of 0.0036 mg/kg/h; group L (GL), LD of 3 mg/kg lidocaine, followed by 3 mg/kg/h and group K (GK), LD of 0.6 mg/kg ketamine, followed by 0.6 mg/kg/h. First a LD of analgesic treatment was administered, followed by induction (to the effect) and beginning of continuous infusion of the analgesic treatment and propofol. The animals were intubated with endotracheal tube of adequate size, and connected to 100% oxygen, being kept under spontaneous ventilation during the entire period of anesthetic maintenance. The infusion of propofol started at 0.34 mg/kg/min and was adjusted so as to maintain the surgical anesthesia plane of Guedel and the cardiovascular parameters within the physiological limits for the species. The cardiorespiratory parameters were measured at different moments basal (before application of any drug) and 5, 15, 20, 30, 40, 50, 60, 70 and 80 min after induction. The surgery started 20 min after anesthetic induction and lasted 60 min. […](AU)