The optimal concentrations of propofol at eye opening and orientation after propofol-remifentanil TCI in Koreans

ABSTRACT

BACKGROUND: The recovery time in propofol target controlled infusion (TCI) can be determined by the context sensitive decrement time (CSDT) using a Multichannel TCI system. Therefore, it is important to obtain the default CSDT in a Multichannel TCI system. The effect-site concentrations for eye opening and orientation in adults after propofol-remifentanil TCI were evaluated according to the CSDT using a Multichannel TCI system. METHODS: After obtaining informed consent and Institutional Review Board approval, 135 ASA Class I or II patients scheduled to undergo elective surgery were divided into 3 groups according to age. The three groups included the following group 1 (n = 45), 18-19 years; group 2 (n = 45), 30-39 years; and group 3 (n = 45), 40-54 years. The propofol infusion was started at a propofol target effect-site concentration (CeT) of 6microg/ml. Anesthesia was maintained primarily with a propofol CeT of 2.5microg/ml, a remifentanil CeT of 6ng/ml and with 67% nitrous oxide in oxygen. The average effect-site concentrations of propofol at eye opening and orientation in each group were estimated. RESULTS: The average range of the effect-site concentrations of propofol at eye opening and orientation after surgery were 0.9-1.1microg/ml. The range of times to eye opening and orientation after stopping the nitrous oxide and infusion after surgery were 10.9-12.9 min. CONCLUSIONS: The average range of the effect-site concentrations of propofol at eye opening and orientation after propofol-remifentanil TCI in Koreans are 0.9-1.1microg/ml.