Effect-site concentration of remifentanil for blunting hemodynamic response to double lumen endobronchial intubation during target controlled infusion-total intravenous anesthesia using propofol with remifentanil

BACKGROUND: This study was undertaken to determine the effect-site concentration of remifentanil for blunting hemodynamic responses to double lumen endobronchial intubation during target controlled infusion (TCI)-total intravenous anesthesia (TIVA) using 4.0 microg/ml of propofol with remifentanil. METHODS: Sixty patients (American society of anesthesiologists physical status classification 1 or 2) were randomly allocated according to the target effect-site concentration of remifentanil (R3.0: remifentanil 3.0 ng/ml; R3.5: remifentanil 3.5 ng/ml; R4.0: remifentanil 4.0 ng/ml). The effect-site concentration of propofol at loss of consciousness was recorded. Mean arterial pressure (MAP), heart rate (HR) and bispectral index (BIS) were recorded at just before remifentanil administration (baseline), at the time of target effect site concentration of remifentanil and propofol, at just before intubation and 1, 2, 3 min after intubation. RESULTS: MAP was significantly increased compared with baseline at 1, 2 min after intubation in R3.0, but was significantly decreased in R4.0. MAP of R3.5 was not different from the baseline after intubation. HR was significantly decreased compared with baseline at the time of target effect site concentration of propofol and immediate before intubation in R3.5 and R4.0. After intubation, HR was significantly increased compared with baseline at only 1 min after intubation and returned to the baseline in R3.0. However, HR was continuously decreased in R4.0. CONCLUSIONS: These findings suggest that effective target effect-site concentration of remifentanil for blunting hemodynamic responses to double lumen endotracheal intubation was 3.5 ng/ml during TCI-TIVA using 4.0 microgram/ml of propofol with remifentanil.