Evaluation Of The Dose Of Remifentanil During One Of The Methods Of Short-Term Anesthetic Induction With Antecedent Administration Of Remifentanil

Purpose: Antecedent administration is a technique used to increase the effect-site concentration (ESC) of remifentanil during intubation. We evaluated the remifentanil dose for one of the methods of short-term anesthetic induction with antecedent administration. Methods: This study included 20 patients aged 18–64 years with American Society of Anesthesiologists (ASA) physical status I or II. They were randomly assigned to the following groups: low-dose (LD) group (0.25 μg/kg/min) and middle-dose (MD) group, (0.5 μg/kg/min). Intubation was performed 3 min after anesthetic induction by using propofol and rocuronium with antecedent administration of remifentanil for 2 min. Pulse oximetry oxygen saturation, hemodynamic parameters, and bispectral index (BIS) values were measured, and the ESCs of remifentanil were calculated. Results: Patient demographics showed no significant differences. None of the patients exhibited oxygen desaturation or experienced a cannot-ventilate situation. Although there were no significant intergroup differences in the degree of decrease in hemodynamic values due to anesthetic induction, the post-intubation hemodynamic and BIS values in the LD group were significantly higher than those in the MD group. Conclusion: We found that administration of remifentanil at a dose of 0.5 μg/kg/min during anesthetic induction with antecedent administration could blunt the cardiovascular response to intubation and the increase in the BIS values due to intubation without causing any respiratory disorders or worsening suppressing of hemodynamics due to anesthetic induction. Therefore, we suggest that the 0.5 μg/kg/min remifentanil dose may be better than the 0.25 μg/kg/min dose in this method of short-term anesthetic induction.