Anesthetic and cardiorespiratory effects of two different infusion rates of propofol were studied in cats premedicated with ketamine-midazolam. Fourteen cats were assigned to one of the two groups (TX1 or TX3). Ketamine (3.0mg/kg) and midazolam (0.3mg/kg) were administered intramuscularly. After 5 minutes, anesthesia was induced by propofol (5.0mg/kg) and maintained by a continuous infusion of propofol (0.1 and 0.3mg/kg/min, TX1 and TX3, respectively). Heart and respiratory rate, rectal temperature, oxygen hemoglobin saturation, end-tidal carbon dioxide and arterial pressure were recorded. Adequate anesthesia was observed in TX3, while animals in TX1 were only lightly sedated. A greater decrease in heart rate, arterial pressure and elevation of end-tidal dioxide carbon was observed in TX3 compared to TX1. It was concluded that administration of propofol at infusion rate of 0.3mg/kg/min provides satisfatory anesthesia, but it results in bradycardia, depression of respiratory function and arterial pressure.
cat; propofol; continuous infusion; ketamine; midazolam
