DOI: 10.36347/sjams.2018.v06i02.029

Pages: 614-618

Dose requirements of Propofol induction depend on patient characteristics and infusion rate. To avoid cardiovascular depression of propofol, slow infusion is recommended during induction. The aim of this study is to determine the best propofol dose with different infusion rates of propofol administered by infusion pumps. A total of 90 American Society of Anaesthesiologists (ASA) I & II patients of both sexes aged 25-55 years were included in this observational study. Patients included in this study were scheduled for elective surgery under general anaesthesia in supine position. Patients were randomly allocated to one of three groups each including 30 patients according to different Propofol infusion speeds used before induction of general anaesthesia. Groups P400, P600 and P800 were infused propofol in rates of 400ml/hr, 600ml/hr and 800ml/hr to each group respectively, until loss of eyelash reflex. The duration of induction was recorded with the amount of propofol infused. The induction dose in mg kg -1 body weight was calculated. Arterial blood pressure and heart rate were recorded before and five consecutive minutes following induction. The doses required to abolish eyelash reflex was 2.25±0.246, 2.71±0.285, and 2.98±0.277 mg kg-1 body weight for Groups P400, P600 and P800 respectively and found significantly different between groups (p<0.05). The decrease in mean arterial pressure was more profound in groups P600 and P800 (30%), in the second minute following induction. Group P400 showed a slight decrease (14%) in the 3rd minute of induction. At faster rates of injection of Propofol the dose required for induction of anaesthesia increased while time for induction was shorter and the decrease in mean blood pressure was more pronounced.