Effects of propofol on the electrocardiogram and systolic blood pressure of healthy cats pre-medicated with acepromazine.

OBJECTIVE: To obtain and analyze the electrocardiogram and systolic blood pressure of cats before, during, and after a continuous infusion of propofol. STUDY DESIGN: Prospective, uncontrolled experimental trial. ANIMALS: Twenty healthy adult crossbred male and female cats aged between 3 and 5 years, weighing 2.8-5.0 kg (mean 3.9 kg). METHODS: Cats were pre-medicated with acepromazine 0.1 mg kg(-1) subcutaneously and anesthesia was induced with intravenous (IV) propofol 6 mg kg(-1) and maintained with a continuous infusion of propofol at 0.5 mg kg(-1) minute(-1) for 60 minutes. Electrocardiographic parameters and systolic blood pressure obtained by Doppler ultrasound were recorded before pre-medication (T0), 30 (T30), and 60 (T60) minutes after beginning the continuous infusion, and 30 minutes after its cessation (T90). Repeated measures anova was used to perform statistical analysis. RESULTS: A significant decrease in heart rate was observed at all time points when compared with T0 values. The PR interval increased significantly at T60 and T90. Systolic blood pressures during anesthesia were significantly lower than at T0 and T90. CONCLUSION AND CLINICAL RELEVANCE: The changes seen were not clinically important in normal cats but given the reduction in heart rate and systolic blood pressure, careful consideration should be given before using this technique in patients in which hypotension or a reduction in heart rate would be poorly tolerated.