Comparison of time to awareness between obese patients and non-obese patients after total intravenous anesthesia with propofol and remifentanil

ABSTRACT

BACKGROUND: The rate of obesity has reached epidemic proportions and is on the rise.There have not been adequate studies on the differences in anesthesiology in obese patient. For this reason, we designed this study to determine the effect of obesity on time to awareness, comparing the use of propofol and remifentanil in general anesthesia. METHODS: We enrolled 55 patients into the study, between ages 16 and 45 years, who had an ASA physical status 1, 2 and who were undergoing general anesthesia for an elective obstetric operation. According to the Asia-Pacific obesity criteria, we divided the patients into 2 groups, the obesity group (BMI > or = 25), and the non-obesity group (BMI < 25). Propofol and remifentanil were infused using TCI for general anesthesia. The bispectral index score (BIS) was used for monitoring depth of anesthesia.During each operation, we tried to keep the BIS between 40 and 55 by controling the target concentration of TCI.We compared the time-to- awareness between the obese patient group and the non-obese patient group. RESULTS: The obesity and the non-obesity group did not show significant difference in awareness times between the obesity group, 412.4 +/- 102.5 s and the non-obesity group, 434.1 +/- 49.1 s. CONCLUSIONS: There was no evidence of a significant difference in time-to-awareness between the obese patient group and the non-obese patient group.The use of remifentanil and propofol work equally well in obese and in non-obese patients anesthesized for elective surgery.