OPTIMUM RATE OF ADMINISTRATION OF PROPOFOL FOR INDUCTION OF ANESTHESIA IN RATS

Twenty rats received propofol 2.5, 5, 10 or 20 mg kg(-1) min(-1) i.v. Brain activity was monitored using the electroencephalogram (EEG). As the endpoint for induction of anaesthesia we used a burst suppression period of Is or longer. At a fast (20 mg kg(-1) min(-1)) rate of admin istration, the induction dose was significantly larger compared with a slower rate (10 mg kg(-1) min(-1)). At a slow rate of administration (2.5 mg kg(-1) min(-1)), the induction dose was also significantly lar ger compared with a rate of 10 mg kg(-1) min(-1). In spite of differen t dose requirements at different rates of administration, duration of anaesthesia was not significantly different.