The Optimal Concentrations of Propofol at Eye Opening and Orientation after Propofol-fentanyl TCI in Koreans / 대한마취과학회지

ABSTRACT

BACKGROUND: We evaluated the optimal concentrations of eye opening and orientation after propofol- fentanyl TCI by CSDT of the pharmacokinetic model using DiprifusorTM in adults retrospectively. Furthermore, we tried to compare those data with the cases of using propofol TCI alone that had been reported. METHODS: After obtaining informed consent and IRB approval, 124 patients of ASA class I or II scheduled for elective surgery were allocated into 3 groups according to age. Three groups were group 1 (n = 40) 18 - 29 years, group 2 (n = 42) 30 - 39 years, group 3 (n = 42) 40 - 54 years. Propofol infusion was started at a propofol target concentration (CT) of 6 microgram/ml by using DiprifusorTM. Anesthesia was mostly maintained with propofol CT 3.5 microgram/ml and fentanyl CT 1.5 ng/ml using a Stelpump and 67% nitrous oxide in oxygen. We estimated the average concentrations of propofol at eye opening and orientation in each group with DiprifusorTM, and we also evaluated the correlation coefficient. RESULTS: Total requirements of propofol in cases of propofol-fentanyl TCI were decreased by 18-26% than in propofol TCI alone. The average concentrations of propofol at eye opening and orientation after surgery were 1.2 - 1.4 microgram/ml. The times to show eye opening and orientation after surgery from stopping of nitrous oxide and infusion were 10.4 - 14.5 min in the propofol-fentanyl group compared with 7.5 - 11 min using propofol TCI alone. CONCLUSIONS: We concluded that the optimal concentrations of propofol at eye opening and orientation after surgery in cases of combination with fentanyl were 1.2 - 1.4 microgram/ml instead of 1.4 - 1.6 microgram/ml with using propofol alone.